Merge pull request #481 from mapbox/crashers

Be more careful about corrupt mbtiles files

.dockerignore

@@ -0,0 +1,4 @@
+# Don't copy Dockerfile or git items
+.gitignore
+.git
+Dockerfile

.gitignore

@@ -0,0 +1,43 @@
+# Compiled Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Autogenerated dependencies
+*.d
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Compiled Dynamic libraries
+*.so
+*.dylib
+*.dll
+
+# Fortran module files
+*.mod
+*.smod
+
+# Compiled Static libraries
+*.lai
+*.la
+*.a
+*.lib
+
+# Executables
+*.exe
+*.out
+*.app
+tippecanoe
+tile-join
+tippecanoe-decode
+tippecanoe-enumerate
+unit
+
+# Vim
+*.swp
+
+# Mac 
+.DS_Store

.travis.yml

@@ -0,0 +1,82 @@
+language: node_js
+node_js:
+  - "6"
+
+sudo: false
+
+matrix:
+  include:
+    # debug+integer-santizer build
+    - os: linux
+      compiler: clang
+      env: CLANG_VERSION='3.8.0' BUILDTYPE=Debug CC="clang-3.8" CXX="clang++-3.8" CXXFLAGS="-fsanitize=integer" CFLAGS="-fsanitize=integer" LDFLAGS="-fsanitize=integer"
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test' ]
+          packages: [ 'libstdc++6','libstdc++-5-dev' ]
+    # debug+leak+address-sanitizer build
+    - os: linux
+      compiler: clang
+      env: CLANG_VERSION='3.8.0' BUILDTYPE=Debug ASAN_OPTIONS=detect_leaks=1 CC="clang-3.8" CXX="clang++-3.8" CXXFLAGS="-fsanitize=address" CFLAGS="-fsanitize=address" LDFLAGS="-fsanitize=address" FEWER=true
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test' ]
+          packages: [ 'libstdc++6','libstdc++-5-dev' ]
+    # coverage+debug build
+    - os: linux
+      compiler: clang
+      env: CLANG_VERSION='3.8.0' BUILDTYPE=Debug CC="clang-3.8" CXX="clang++-3.8" CXXFLAGS="--coverage" CFLAGS="--coverage" LDFLAGS="--coverage"
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test' ]
+          packages: [ 'libstdc++6','libstdc++-5-dev' ]
+    # release+linux+g++
+    - os: linux
+      compiler: gcc
+      env: BUILDTYPE=Release CC="gcc-4.9" CXX="g++-4.9"
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test']
+          packages: [ 'g++-4.9' ]
+    # release+linux+clang++
+    - os: linux
+      compiler: clang
+      env: CLANG_VERSION='3.8.0' BUILDTYPE=Release CC="clang-3.8" CXX="clang++-3.8"
+      addons:
+        apt:
+          sources: ['ubuntu-toolchain-r-test' ]
+          packages: [ 'libstdc++6','libstdc++-5-dev' ]
+    # release+osx
+    - os: osx
+      compiler: clang
+      env: BUILDTYPE=Release
+    # debug+osx
+    - os: osx
+      compiler: clang
+      env: BUILDTYPE=Debug
+
+before_install:
+  - DEPS_DIR="${TRAVIS_BUILD_DIR}/deps"
+  - export PATH=${DEPS_DIR}/bin:${PATH} && mkdir -p ${DEPS_DIR}
+  - |
+    if [[ ${CLANG_VERSION:-false} != false ]]; then
+      export CCOMPILER='clang'
+      export CXXCOMPILER='clang++'
+      CLANG_URL="https://mason-binaries.s3.amazonaws.com/${TRAVIS_OS_NAME}-x86_64/clang/${CLANG_VERSION}.tar.gz"
+      travis_retry wget --quiet -O - ${CLANG_URL} | tar --strip-components=1 -xz -C ${DEPS_DIR}
+    fi
+
+install:
+ - BUILDTYPE=${BUILDTYPE} make -j
+
+script:
+ - npm install geobuf
+ - if [ -n "${FEWER}" ]; then
+       BUILDTYPE=${BUILDTYPE} make fewer-tests; else
+       BUILDTYPE=${BUILDTYPE} make test geobuf-test;
+   fi
+ - if [ -n "${COVERAGE}" ]; then
+       /usr/bin/llvm-cov-3.5 -lp *.o;
+       pip install --user cpp-coveralls;
+       ~/.local/bin/coveralls --no-gcov -i ./ --exclude clipper;
+   fi

CHANGELOG.md

@@ -1,3 +1,495 @@
+## 1.26.3
+
+* Guard against impossible coordinates when decoding tilesets
+
+## 1.26.2
+
+* Make sure to encode tile-joined integers as ints, not doubles
+
+## 1.26.1
+
+* Add tile-join option to rename layers
+
+## 1.26.0
+
+Fix error when parsing attributes with empty-string keys
+
+## 1.25.0
+
+* Add --coalesce-smallest-as-needed strategy for reducing tile sizes
+* Add --stats option to tipppecanoe-decode
+
+## 1.24.1
+
+* Limit the size and depth of the string pool for better performance
+
+## 1.24.0
+
+* Add feature filters using the Mapbox GL Style Specification filter syntax
+
+## 1.23.0
+
+* Add input support for Geobuf file format
+
+## 1.22.2
+
+* Add better diagnostics for NaN or Infinity in input JSON
+
+## 1.22.1
+
+* Fix tilestats generation when long string attribute values are elided
+* Add option not to produce tilestats
+* Add tile-join options to select zoom levels to copy
+
+## 1.22.0
+
+* Add options to filter each tile's contents through a shell pipeline
+
+## 1.21.0
+
+* Generate layer, feature, and attribute statistics as part of tileset metadata
+
+## 1.20.1
+
+* Close mbtiles file properly when there are no valid features in the input
+
+## 1.20.0
+
+* Add long options to tippecanoe-decode and tile-join. Add --quiet to tile-join.
+
+## 1.19.3
+
+* Upgrade protozero to version 1.5.2
+
+## 1.19.2
+
+* Ignore UTF-8 byte order mark if present
+
+## 1.19.1
+
+* Add an option to increase maxzoom if features are still being dropped
+
+## 1.19.0
+
+* Tile-join can merge and create directories, not only mbtiles
+* Maxzoom guessing (-zg) takes into account resolution within each feature
+
+## 1.18.2
+
+* Fix crash with very long (>128K) attribute values
+
+## 1.18.1
+
+* Only warn once about invalid polygons in tippecanoe-decode
+
+## 1.18.0
+
+* Fix compression of tiles in tile-join
+* Calculate the tileset bounding box in tile-join from the tile boundaries
+
+## 1.17.7
+
+* Enforce polygon winding and closure rules in tippecanoe-decode
+
+## 1.17.6
+
+* Add tile-join options to set name, attribution, description
+
+## 1.17.5
+
+* Preserve the tileset names from the source mbtiles in tile-join
+
+## 1.17.4
+
+* Fix RFC 8142 support: Don't try to split *all* memory mapped files
+
+## 1.17.3
+
+* Support RFC 8142 GeoJSON text sequences
+
+## 1.17.2
+
+* Organize usage output the same way as in the README
+
+## 1.17.1
+
+* Add -T option to coerce the types of feature attributes
+
+## 1.17.0
+
+* Add -zg option to guess an appropriate maxzoom
+
+## 1.16.17
+
+* Clean up JSON parsing at the end of each FeatureCollection
+  to avoid running out of memory
+
+## 1.16.16
+
+* Add tile-join options to include or exclude specific layers
+
+## 1.16.15
+
+* Add --output-to-directory and --no-tile-compression options
+
+## 1.16.14
+
+* Add --description option for mbtiles metadata
+* Clean up some utility functions
+
+## 1.16.13
+
+* Add --detect-longitude-wraparound option
+
+## 1.16.12
+
+* Stop processing higher zooms when a feature reaches its explicit maxzoom tag
+
+## 1.16.11
+
+* Remove polygon splitting, since polygon cleaning is now fast enough
+
+## 1.16.10
+
+* Add a tippecanoe-decode option to specify layer names
+
+## 1.16.9
+
+* Clean up layer name handling to fix layer merging crash
+
+## 1.16.8
+
+* Fix some code that could sometimes try to divide by zero
+* Add check for $TIPPECANOE_MAX_THREADS environmental variable
+
+## 1.16.7
+
+* Fix area of placeholders for degenerate multipolygons
+
+## 1.16.6
+
+* Upgrade Wagyu to 0.3.0; downgrade C++ requirement to C++ 11
+
+## 1.16.5
+
+* Add -z and -Z options to tippecanoe-decode
+
+## 1.16.4
+
+* Use Wagyu's quick_lr_clip() instead of a separate implementation
+
+## 1.16.3
+
+* Upgrade Wagyu to bfbf2893
+
+## 1.16.2
+
+* Associate attributes with the right layer when explicitly tagged
+
+## 1.16.1
+
+* Choose a deeper starting tile than 0/0/0 if there is one that contains
+  all the features
+
+## 1.16.0
+
+* Switch from Clipper to Wagyu for polygon topology correction
+
+## 1.15.4
+
+* Dot-dropping with -r/-B doesn't apply if there is a per-feature minzoom tag
+
+## 1.15.3
+
+* Round coordinates in low-zoom grid math instead of truncating
+
+## 1.15.2
+
+* Add --grid-low-zooms option to snap low-zoom features to the tile grid
+
+## 1.15.1
+
+* Stop --drop-smallest-as-needed from always dropping all points
+
+## 1.15.0
+
+* New strategies for making tiles smaller, with uniform behavior across
+  the whole zoom level: --increase-gamma-as-needed,
+  --drop-densest-as-needed, --drop-fraction-as-needed,
+  --drop-smallest-as-needed.
+* Option to specify the maximum tile size in bytes
+* Option to turn off tiny polygon reduction
+* Better error checking in JSON parsing
+
+## 1.14.4
+
+* Make -B/-r feature-dropping consistent between tiles and zoom levels
+
+## 1.14.3
+
+* Add --detect-shared-borders option for better polygon simplification
+
+## 1.14.2
+
+* Enforce that string feature attributes must be encoded as UTF-8
+
+## 1.14.1
+
+* Whitespace after commas in tile-join .csv input is no longer significant
+
+## 1.14.0
+
+* Tile-join is multithreaded and can merge multiple vector mbtiles files together
+
+## 1.13.0
+
+* Add the ability to specify layer names within the GeoJSON input
+
+## 1.12.11
+
+* Don't try to revive a placeholder for a degenerate polygon that had negative area
+
+## 1.12.10
+
+* Pass feature IDs through in tile-join
+
+## 1.12.9
+
+* Clean up parsing and serialization. Provide some context with parsing errors.
+
+## 1.12.8
+
+* Fix the spelling of the --preserve-input-order option
+
+## 1.12.7
+
+* Support the "id" field of GeoJSON objects and vector tile features
+
+## 1.12.6
+
+* Fix error reports when reading from an empty file with parallel input
+
+## 1.12.5
+
+* Add an option to vary the level of line and polygon simplification
+* Be careful not to produce an empty tile if there was a feature with
+  empty geometry.
+
+## 1.12.4
+
+* Be even more careful not to produce features with empty geometry
+
+## 1.12.3
+
+* Fix double-counted progress in the progress indicator
+
+## 1.12.2
+
+* Add ability to specify a projection to tippecanoe-decode
+
+## 1.12.1
+
+* Fix incorrect tile layer version numbers in tile-join output
+
+## 1.12.0
+
+* Fix a tile-join bug that would retain fields that were supposed to be excluded
+
+## 1.11.9
+
+* Add minimal support for alternate input projections (EPSG:3857).
+
+## 1.11.8
+
+* Add an option to calculate the density of features as a feature attribute
+
+## 1.11.7
+
+* Keep metadata together with geometry for features that don't span many tiles,
+  to avoid extra memory load from indexing into a separate metadata file
+
+## 1.11.6
+
+* Reduce the size of critical data structures to reduce dynamic memory use
+
+## 1.11.5
+
+* Let zoom level 0 have just as much extent and buffer as any other zoom
+* Fix tippecanoe-decode bug that would sometimes show outer rings as inner
+
+## 1.11.4
+
+* Don't let polygons with nonzero area disappear during cleaning
+
+## 1.11.3
+
+* Internal code cleanup
+
+## 1.11.2
+
+* Update Clipper to fix potential crash
+
+## 1.11.1
+
+* Make better use of C++ standard libraries
+
+## 1.11.0
+
+* Convert C source files to C++
+
+## 1.10.0
+
+* Upgrade Clipper to fix potential crashes and improve polygon topology
+
+## 1.9.16
+
+* Switch to protozero as the library for reading and writing protocol buffers
+
+## 1.9.15
+
+* Add option not to clip features
+
+## 1.9.14
+
+* Clean up polygons after coalescing, if necessary
+
+## 1.9.13
+
+* Don't trust the OS so much about how many files can be open
+
+## 1.9.12
+
+* Limit the size of the parallel parsing streaming input buffer
+* Add an option to set the tileset's attribution
+
+## 1.9.11
+
+* Fix a line simplification crash when a segment degenerates to a single point
+
+## 1.9.10
+
+* Warn if temporary disk space starts to run low
+
+## 1.9.9
+
+* Add --drop-polygons to drop a fraction of polygons by zoom level
+* Only complain once about failing to clean polygons
+
+## 1.9.8
+
+* Use an on-disk radix sort for the index to control virtual memory thrashing
+  when the geometry and index are too large to fit in memory
+
+## 1.9.7
+
+* Fix build problem (wrong spelling of long long max/min constants)
+
+## 1.9.6
+
+* Add an option to give specific layer names to specific input files
+
+## 1.9.5
+
+* Remove temporary files that were accidentally left behind
+* Be more careful about checking memory allocations and array bounds
+* Add GNU-style long options
+
+## 1.9.4
+
+* Tippecanoe-decode can decode .pbf files that aren't in an .mbtiles container
+
+## 1.9.3
+
+* Don't get stuck in a loop trying to split up very small, very complicated polygons
+
+## 1.9.2
+
+* Increase maximum tile size for tippecanoe-decode
+
+## 1.9.1
+
+* Incorporate Mapnik's Clipper upgrades for consistent results between Mac and Linux
+
+## 1.9.0
+
+* Claim vector tile version 2 in mbtiles
+* Split too-complex polygons into multiple features
+
+## 1.8.1
+
+* Bug fixes to maxzoom, and more tests
+
+## 1.8.0
+
+* There are tests that can be run with "make test".
+
+## 1.7.2
+
+* Feature properties that are arrays or hashes get stringified
+  rather than being left out with a warning.
+
+## 1.7.1
+
+* Make clipping behavior with no buffer consistent with Mapnik.
+  Features that are exactly on a tile boundary appear in both tiles.
+
+## 1.7.0
+
+* Parallel processing of input with -P works with streamed input too
+* Error handling if unsupported options given to -p or -a
+
+## 1.6.4
+
+* Fix crashing bug when layers are being merged with -l
+
+## 1.6.3
+
+* Add an option to do line simplification only at zooms below maxzoom
+
+## 1.6.2
+
+* Make sure line simplification matches on opposite sides of a tile boundary
+
+## 1.6.1
+
+* Use multiple threads for line simplification and polygon cleaning
+
+## 1.6.0
+
+* Add option of parallelized input when reading from a line-delimited file
+
+## 1.5.1
+
+* Fix internal error when number of CPUs is not a power of 2
+* Add missing #include
+
+## 1.5.0
+
+* Base zoom for dot-dropping can be specified independently of
+  maxzoom for tiling.
+* Tippecanoe can calculate a base zoom and drop rate for you.
+
+## 1.4.3
+
+* Encode numeric attributes as integers instead of floating point if possible
+
+## 1.4.2
+
+* Bug fix for problem that would occasionally produce empty point geometries
+* More bug fixes for polygon generation
+
+## 1.4.1
+
+* Features that cross the antimeridian are split into two parts instead
+  of being partially lost off the edge
+
+## 1.4.0
+
+* More polygon correctness
+* Query the system for the number of available CPUs instead of guessing
+* Merge input files into one layer if a layer name is specified
+* Document and install tippecanoe-enumerate and tippecanoe-decode
+
 ## 1.3.0
 
 * Tile generation is multithreaded to take advantage of multiple CPUs
@@ -10,6 +502,7 @@
 * Output of `decode` utility is now in GeoJSON format
 * Tile generation with a minzoom spends less time on unused lower zoom levels
 * Bare geometries without a Feature wrapper are accepted
+* Default tile resolution is 4096 units at all zooms since renderers assume it
 
 ## 1.2.0
 

Dockerfile

@@ -0,0 +1,24 @@
+# Start from ubuntu
+FROM ubuntu:17.04
+
+# Update repos and install dependencies
+RUN apt-get update \
+  && apt-get -y upgrade \
+  && apt-get -y install build-essential libsqlite3-dev zlib1g-dev
+
+# Create a directory and copy in all files
+RUN mkdir -p /tmp/tippecanoe-src
+WORKDIR /tmp/tippecanoe-src
+COPY . /tmp/tippecanoe-src
+
+# Build tippecanoe
+RUN make \
+  && make install
+
+# Remove the temp directory and unneeded packages
+WORKDIR /
+RUN rm -rf /tmp/tippecanoe-src \
+  && apt-get -y remove --purge build-essential && apt-get -y autoremove
+
+# Run the default command to show usage
+CMD tippecanoe --help

MADE_WITH.md

@@ -1,4 +1,4 @@
-## [Visualizing a Month of Lightning](http://rousseau.io/2015/03/23/visualizing-a-month-of-lightning/) by Jordan Rousseau
+## [Visualizing a Month of Lightning](http://rousseau.io/2015/03/23/visualizing-a-month-of-lightning) by Jordan Rousseau
 
 ![](http://rousseau.io/assets/img/ltg-studio-style.png)
 

Makefile

@@ -1,53 +1,243 @@
 PREFIX ?= /usr/local
-MANDIR ?= /usr/share/man/man1/
+MANDIR ?= $(PREFIX)/share/man/man1/
+BUILDTYPE ?= Release
+SHELL = /bin/bash
 
-all: tippecanoe enumerate decode tile-join
+# inherit from env if set
+CC := $(CC)
+CXX := $(CXX)
+CFLAGS := $(CFLAGS)
+CXXFLAGS := $(CXXFLAGS) -std=c++11
+LDFLAGS := $(LDFLAGS)
+WARNING_FLAGS := -Wall -Wshadow -Wsign-compare
+RELEASE_FLAGS := -O3 -DNDEBUG
+DEBUG_FLAGS := -O0 -DDEBUG -fno-inline-functions -fno-omit-frame-pointer
+
+ifeq ($(BUILDTYPE),Release)
+	FINAL_FLAGS := -g $(WARNING_FLAGS) $(RELEASE_FLAGS)
+else
+	FINAL_FLAGS := -g $(WARNING_FLAGS) $(DEBUG_FLAGS)
+endif
+
+all: tippecanoe tippecanoe-enumerate tippecanoe-decode tile-join unit geojson2nd
 
 docs: man/tippecanoe.1
 
-install: tippecanoe
+install: tippecanoe tippecanoe-enumerate tippecanoe-decode tile-join
 	mkdir -p $(PREFIX)/bin
+	mkdir -p $(MANDIR)
 	cp tippecanoe $(PREFIX)/bin/tippecanoe
-	cp man/tippecanoe.1 $(MANDIR)
+	cp tippecanoe-enumerate $(PREFIX)/bin/tippecanoe-enumerate
+	cp tippecanoe-decode $(PREFIX)/bin/tippecanoe-decode
+	cp tile-join $(PREFIX)/bin/tile-join
+	cp man/tippecanoe.1 $(MANDIR)/tippecanoe.1
+
+uninstall:
+	rm $(PREFIX)/bin/tippecanoe $(PREFIX)/bin/tippecanoe-enumerate $(PREFIX)/bin/tippecanoe-decode $(PREFIX)/bin/tile-join $(MANDIR)/tippecanoe.1
 
 man/tippecanoe.1: README.md
 	md2man-roff README.md > man/tippecanoe.1
 
-vector_tile.pb.cc vector_tile.pb.h: vector_tile.proto
-	protoc --cpp_out=. vector_tile.proto
-
 PG=
 
-H = $(shell find . '(' -name '*.h' -o -name '*.hh' ')')
-C = $(shell find . '(' -name '*.c' -o -name '*.cc' ')')
+H = $(wildcard *.h) $(wildcard *.hpp)
+C = $(wildcard *.c) $(wildcard *.cpp)
 
-INCLUDES = -I/usr/local/include
+INCLUDES = -I/usr/local/include -I.
 LIBS = -L/usr/local/lib
 
-tippecanoe: geojson.o jsonpull.o vector_tile.pb.o tile.o clip.o pool.o mbtiles.o geometry.o projection.o memfile.o clipper/clipper.o
-	g++ $(PG) $(LIBS) -O3 -g -Wall -o $@ $^ -lm -lz -lprotobuf-lite -lsqlite3 -lpthread
+tippecanoe: geojson.o jsonpull/jsonpull.o tile.o pool.o mbtiles.o geometry.o projection.o memfile.o mvt.o serial.o main.o text.o dirtiles.o plugin.o read_json.o write_json.o geobuf.o evaluator.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CXXFLAGS) -o $@ $^ $(LDFLAGS) -lm -lz -lsqlite3 -lpthread
 
-enumerate: enumerate.o
-	gcc $(PG) $(LIBS) -O3 -g -Wall -o $@ $^ -lsqlite3
+tippecanoe-enumerate: enumerate.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CFLAGS) -o $@ $^ $(LDFLAGS) -lsqlite3
 
-decode: decode.o vector_tile.pb.o projection.o
-	g++ $(PG) $(LIBS) -O3 -g -Wall -o $@ $^ -lm -lz -lprotobuf-lite -lsqlite3
+tippecanoe-decode: decode.o projection.o mvt.o write_json.o text.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CXXFLAGS) -o $@ $^ $(LDFLAGS) -lm -lz -lsqlite3
 
-tile-join: tile-join.o vector_tile.pb.o projection.o pool.o mbtiles.o
-	g++ $(PG) $(LIBS) -O3 -g -Wall -o $@ $^ -lm -lz -lprotobuf-lite -lsqlite3
+tile-join: tile-join.o projection.o pool.o mbtiles.o mvt.o memfile.o dirtiles.o jsonpull/jsonpull.o text.o evaluator.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CXXFLAGS) -o $@ $^ $(LDFLAGS) -lm -lz -lsqlite3 -lpthread
 
-libjsonpull.a: jsonpull.o
-	ar rc $@ $^
-	ranlib $@
+geojson2nd: geojson2nd.o jsonpull/jsonpull.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CXXFLAGS) -o $@ $^ $(LDFLAGS) -lm -lz -lsqlite3 -lpthread
 
-%.o: %.c $(H)
-	cc $(PG) $(INCLUDES) -O3 -g -Wall -c $<
+unit: unit.o text.o
+	$(CXX) $(PG) $(LIBS) $(FINAL_FLAGS) $(CXXFLAGS) -o $@ $^ $(LDFLAGS) -lm -lz -lsqlite3 -lpthread
 
-%.o: %.cc $(H)
-	g++ $(PG) $(INCLUDES) -O3 -g -Wall -c $<
+-include $(wildcard *.d)
+
+%.o: %.c
+	$(CC) -MMD $(PG) $(INCLUDES) $(FINAL_FLAGS) $(CFLAGS) -c -o $@ $<
+
+%.o: %.cpp
+	$(CXX) -MMD $(PG) $(INCLUDES) $(FINAL_FLAGS) $(CXXFLAGS) -c -o $@ $<
 
 clean:
-	rm tippecanoe *.o
+	rm -f ./tippecanoe ./tippecanoe-* ./tile-join ./unit *.o *.d */*.o */*.d
 
 indent:
-	clang-format -i -style="{BasedOnStyle: Google, IndentWidth: 8, UseTab: Always, AllowShortIfStatementsOnASingleLine: false, ColumnLimit: 0, ContinuationIndentWidth: 8, SpaceAfterCStyleCast: true, IndentCaseLabels: false, AllowShortBlocksOnASingleLine: false, AllowShortFunctionsOnASingleLine: false}" $(C) $(H)
+	clang-format -i -style="{BasedOnStyle: Google, IndentWidth: 8, UseTab: Always, AllowShortIfStatementsOnASingleLine: false, ColumnLimit: 0, ContinuationIndentWidth: 8, SpaceAfterCStyleCast: true, IndentCaseLabels: false, AllowShortBlocksOnASingleLine: false, AllowShortFunctionsOnASingleLine: false, SortIncludes: false}" $(C) $(H)
+
+TESTS = $(wildcard tests/*/out/*.json)
+SPACE = $(NULL) $(NULL)
+
+test: tippecanoe tippecanoe-decode $(addsuffix .check,$(TESTS)) raw-tiles-test parallel-test pbf-test join-test enumerate-test decode-test join-filter-test unit
+	./unit
+
+# Work around Makefile and filename punctuation limits: _ for space, @ for :, % for /
+%.json.check:
+	./tippecanoe -aD -f -o $@.mbtiles $(subst @,:,$(subst %,/,$(subst _, ,$(patsubst %.json.check,%,$(word 4,$(subst /, ,$@)))))) $(wildcard $(subst $(SPACE),/,$(wordlist 1,2,$(subst /, ,$@)))/*.json) < /dev/null
+	./tippecanoe-decode $@.mbtiles > $@.out
+	cmp $@.out $(patsubst %.check,%,$@)
+	rm $@.out $@.mbtiles
+
+geobuf-test: geojson2nd $(addsuffix .checkbuf,$(TESTS))
+
+# For quicker address sanitizer build, hope that regular JSON parsing is tested enough by parallel and join tests
+fewer-tests: tippecanoe tippecanoe-decode geobuf-test raw-tiles-test parallel-test pbf-test join-test enumerate-test decode-test join-filter-test unit
+
+# XXX Use proper makefile rules instead of a for loop
+%.json.checkbuf:
+	for i in $(wildcard $(subst $(SPACE),/,$(wordlist 1,2,$(subst /, ,$@)))/*.json); do ./geojson2nd -w $$i | ./node_modules/geobuf/bin/json2geobuf > $$i.geobuf; done
+	./tippecanoe -aD -f -o $@.mbtiles $(subst @,:,$(subst %,/,$(subst _, ,$(patsubst %.json.checkbuf,%,$(word 4,$(subst /, ,$@)))))) $(addsuffix .geobuf,$(wildcard $(subst $(SPACE),/,$(wordlist 1,2,$(subst /, ,$@)))/*.json)) < /dev/null
+	./tippecanoe-decode $@.mbtiles | sed 's/checkbuf/check/g' > $@.out
+	cmp $@.out $(patsubst %.checkbuf,%,$@)
+	rm $@.out $@.mbtiles
+
+parallel-test:
+	mkdir -p tests/parallel
+	perl -e 'for ($$i = 0; $$i < 20; $$i++) { $$lon = rand(360) - 180; $$lat = rand(180) - 90; $$k = rand(1); $$v = rand(1); print "{ \"type\": \"Feature\", \"properties\": { \"yes\": \"no\", \"who\": 1, \"$$k\": \"$$v\" }, \"geometry\": { \"type\": \"Point\", \"coordinates\": [ $$lon, $$lat ] } }\n"; }' > tests/parallel/in1.json
+	perl -e 'for ($$i = 0; $$i < 300000; $$i++) { $$lon = rand(360) - 180; $$lat = rand(180) - 90; print "{ \"type\": \"Feature\", \"properties\": { }, \"geometry\": { \"type\": \"Point\", \"coordinates\": [ $$lon, $$lat ] } }\n"; }' > tests/parallel/in2.json
+	perl -e 'for ($$i = 0; $$i < 20; $$i++) { $$lon = rand(360) - 180; $$lat = rand(180) - 90; print "{ \"type\": \"Feature\", \"properties\": { }, \"geometry\": { \"type\": \"Point\", \"coordinates\": [ $$lon, $$lat ] } }\n"; }' > tests/parallel/in3.json
+	perl -e 'for ($$i = 0; $$i < 20; $$i++) { $$lon = rand(360) - 180; $$lat = rand(180) - 90; $$v = rand(1); print "{ \"type\": \"Feature\", \"properties\": { }, \"tippecanoe\": { \"layer\": \"$$v\" }, \"geometry\": { \"type\": \"Point\", \"coordinates\": [ $$lon, $$lat ] } }\n"; }' > tests/parallel/in4.json
+	echo -n "" > tests/parallel/empty1.json
+	echo "" > tests/parallel/empty2.json
+	./tippecanoe -z5 -f -pi -l test -n test -o tests/parallel/linear-file.mbtiles tests/parallel/in[1234].json tests/parallel/empty[12].json
+	./tippecanoe -z5 -f -pi -l test -n test -P -o tests/parallel/parallel-file.mbtiles tests/parallel/in[1234].json tests/parallel/empty[12].json
+	cat tests/parallel/in[1234].json | ./tippecanoe -z5 -f -pi -l test -n test -o tests/parallel/linear-pipe.mbtiles
+	cat tests/parallel/in[1234].json | ./tippecanoe -z5 -f -pi -l test -n test -P -o tests/parallel/parallel-pipe.mbtiles
+	cat tests/parallel/in[1234].json | sed 's/^/@/' | tr '@' '\036' | ./tippecanoe -z5 -f -pi -l test -n test -o tests/parallel/implicit-pipe.mbtiles
+	./tippecanoe -z5 -f -pi -l test -n test -P -o tests/parallel/parallel-pipes.mbtiles <(cat tests/parallel/in1.json) <(cat tests/parallel/empty1.json) <(cat tests/parallel/empty2.json) <(cat tests/parallel/in2.json) /dev/null <(cat tests/parallel/in3.json) <(cat tests/parallel/in4.json)
+	./tippecanoe-decode tests/parallel/linear-file.mbtiles > tests/parallel/linear-file.json
+	./tippecanoe-decode tests/parallel/parallel-file.mbtiles > tests/parallel/parallel-file.json
+	./tippecanoe-decode tests/parallel/linear-pipe.mbtiles > tests/parallel/linear-pipe.json
+	./tippecanoe-decode tests/parallel/parallel-pipe.mbtiles > tests/parallel/parallel-pipe.json
+	./tippecanoe-decode tests/parallel/implicit-pipe.mbtiles > tests/parallel/implicit-pipe.json
+	./tippecanoe-decode tests/parallel/parallel-pipes.mbtiles > tests/parallel/parallel-pipes.json
+	cmp tests/parallel/linear-file.json tests/parallel/parallel-file.json
+	cmp tests/parallel/linear-file.json tests/parallel/linear-pipe.json
+	cmp tests/parallel/linear-file.json tests/parallel/parallel-pipe.json
+	cmp tests/parallel/linear-file.json tests/parallel/implicit-pipe.json
+	cmp tests/parallel/linear-file.json tests/parallel/parallel-pipes.json
+	rm tests/parallel/*.mbtiles tests/parallel/*.json
+
+raw-tiles-test:	
+	./tippecanoe -f -e tests/raw-tiles/raw-tiles tests/raw-tiles/hackspots.geojson -pC
+	diff -x '*.DS_Store' -rq tests/raw-tiles/raw-tiles tests/raw-tiles/compare
+	rm -rf tests/raw-tiles/raw-tiles
+
+decode-test:
+	mkdir -p tests/muni/decode
+	./tippecanoe -z11 -Z11 -f -o tests/muni/decode/multi.mbtiles tests/muni/*.json
+	./tippecanoe-decode -l subway tests/muni/decode/multi.mbtiles > tests/muni/decode/multi.mbtiles.json.check
+	./tippecanoe-decode -c tests/muni/decode/multi.mbtiles > tests/muni/decode/multi.mbtiles.pipeline.json.check
+	./tippecanoe-decode --stats tests/muni/decode/multi.mbtiles > tests/muni/decode/multi.mbtiles.stats.json.check
+	cmp tests/muni/decode/multi.mbtiles.json.check tests/muni/decode/multi.mbtiles.json
+	cmp tests/muni/decode/multi.mbtiles.pipeline.json.check tests/muni/decode/multi.mbtiles.pipeline.json
+	cmp tests/muni/decode/multi.mbtiles.stats.json.check tests/muni/decode/multi.mbtiles.stats.json
+	rm -f tests/muni/decode/multi.mbtiles.json.check tests/muni/decode/multi.mbtiles tests/muni/decode/multi.mbtiles.pipeline.json.check tests/muni/decode/multi.mbtiles.stats.json.check
+
+pbf-test:
+	./tippecanoe-decode tests/pbf/11-328-791.vector.pbf 11 328 791 > tests/pbf/11-328-791.vector.pbf.out
+	cmp tests/pbf/11-328-791.json tests/pbf/11-328-791.vector.pbf.out
+	rm tests/pbf/11-328-791.vector.pbf.out
+	./tippecanoe-decode -s EPSG:3857 tests/pbf/11-328-791.vector.pbf 11 328 791 > tests/pbf/11-328-791.3857.vector.pbf.out
+	cmp tests/pbf/11-328-791.3857.json tests/pbf/11-328-791.3857.vector.pbf.out
+	rm tests/pbf/11-328-791.3857.vector.pbf.out
+
+enumerate-test:
+	./tippecanoe -z5 -f -o tests/ne_110m_admin_0_countries/out/enum.mbtiles tests/ne_110m_admin_0_countries/in.json
+	./tippecanoe-enumerate tests/ne_110m_admin_0_countries/out/enum.mbtiles > tests/ne_110m_admin_0_countries/out/enum.check
+	cmp tests/ne_110m_admin_0_countries/out/enum tests/ne_110m_admin_0_countries/out/enum.check
+	rm tests/ne_110m_admin_0_countries/out/enum.mbtiles tests/ne_110m_admin_0_countries/out/enum.check
+
+join-test:
+	./tippecanoe -f -z12 -o tests/join-population/tabblock_06001420.mbtiles tests/join-population/tabblock_06001420.json
+	./tippecanoe -f -Z5 -z10 -o tests/join-population/macarthur.mbtiles -l macarthur tests/join-population/macarthur.json
+	./tile-join -f -Z6 -z9 -o tests/join-population/macarthur-6-9.mbtiles tests/join-population/macarthur.mbtiles
+	./tippecanoe-decode tests/join-population/macarthur-6-9.mbtiles > tests/join-population/macarthur-6-9.mbtiles.json.check
+	cmp tests/join-population/macarthur-6-9.mbtiles.json.check tests/join-population/macarthur-6-9.mbtiles.json
+	rm -f tests/join-population/macarthur-6-9.mbtiles.json.check tests/join-population/macarthur-6-9.mbtiles
+	./tippecanoe -f -d10 -D10 -Z9 -z11 -o tests/join-population/macarthur2.mbtiles -l macarthur tests/join-population/macarthur2.json
+	./tile-join --quiet --force -o tests/join-population/joined.mbtiles -x GEOID10 -c tests/join-population/population.csv tests/join-population/tabblock_06001420.mbtiles
+	./tile-join --quiet --force --no-tile-stats -o tests/join-population/joined-no-tile-stats.mbtiles -x GEOID10 -c tests/join-population/population.csv tests/join-population/tabblock_06001420.mbtiles
+	./tile-join -f -i -o tests/join-population/joined-i.mbtiles -x GEOID10 -c tests/join-population/population.csv tests/join-population/tabblock_06001420.mbtiles
+	./tile-join -f -o tests/join-population/merged.mbtiles tests/join-population/tabblock_06001420.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2.mbtiles
+	./tile-join -f -c tests/join-population/windows.csv -o tests/join-population/windows.mbtiles tests/join-population/macarthur.mbtiles
+	./tippecanoe-decode --maximum-zoom=11 --minimum-zoom=4 tests/join-population/joined.mbtiles > tests/join-population/joined.mbtiles.json.check
+	./tippecanoe-decode --maximum-zoom=11 --minimum-zoom=4 tests/join-population/joined-no-tile-stats.mbtiles > tests/join-population/joined-no-tile-stats.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/joined-i.mbtiles > tests/join-population/joined-i.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/merged.mbtiles > tests/join-population/merged.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/windows.mbtiles > tests/join-population/windows.mbtiles.json.check
+	cmp tests/join-population/joined.mbtiles.json.check tests/join-population/joined.mbtiles.json
+	cmp tests/join-population/joined-no-tile-stats.mbtiles.json.check tests/join-population/joined-no-tile-stats.mbtiles.json
+	cmp tests/join-population/joined-i.mbtiles.json.check tests/join-population/joined-i.mbtiles.json
+	cmp tests/join-population/merged.mbtiles.json.check tests/join-population/merged.mbtiles.json
+	cmp tests/join-population/windows.mbtiles.json.check tests/join-population/windows.mbtiles.json
+	./tile-join -f -l macarthur -n "macarthur name" -N "macarthur description" -A "macarthur attribution" -o tests/join-population/just-macarthur.mbtiles tests/join-population/merged.mbtiles
+	./tile-join -f -L macarthur -o tests/join-population/no-macarthur.mbtiles tests/join-population/merged.mbtiles
+	./tippecanoe-decode tests/join-population/just-macarthur.mbtiles > tests/join-population/just-macarthur.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/no-macarthur.mbtiles > tests/join-population/no-macarthur.mbtiles.json.check
+	cmp tests/join-population/just-macarthur.mbtiles.json.check tests/join-population/just-macarthur.mbtiles.json
+	cmp tests/join-population/no-macarthur.mbtiles.json.check tests/join-population/no-macarthur.mbtiles.json	
+	./tile-join --no-tile-compression -f -e tests/join-population/raw-merged-folder tests/join-population/tabblock_06001420.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2.mbtiles
+	diff -x '*.DS_Store' -rq tests/join-population/raw-merged-folder tests/join-population/raw-merged-folder-compare
+	./tippecanoe -z12 -f -e tests/join-population/tabblock_06001420-folder tests/join-population/tabblock_06001420.json
+	./tippecanoe -Z5 -z10 -f -e tests/join-population/macarthur-folder -l macarthur tests/join-population/macarthur.json
+	./tippecanoe -d10 -D10 -Z9 -z11 -f -e tests/join-population/macarthur2-folder -l macarthur tests/join-population/macarthur2.json
+	./tile-join -f -o tests/join-population/merged-folder.mbtiles tests/join-population/tabblock_06001420-folder tests/join-population/macarthur-folder tests/join-population/macarthur2-folder
+	./tippecanoe-decode tests/join-population/merged-folder.mbtiles > tests/join-population/merged-folder.mbtiles.json.check
+	cmp tests/join-population/merged-folder.mbtiles.json.check tests/join-population/merged-folder.mbtiles.json
+	./tile-join -n "merged name" -N "merged description" -f -e tests/join-population/merged-mbtiles-to-folder tests/join-population/tabblock_06001420.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2.mbtiles
+	./tile-join -n "merged name" -N "merged description" -f -e tests/join-population/merged-folders-to-folder tests/join-population/tabblock_06001420-folder tests/join-population/macarthur-folder tests/join-population/macarthur2-folder
+	diff -x '*.DS_Store' -rq tests/join-population/merged-mbtiles-to-folder tests/join-population/merged-folders-to-folder
+	./tile-join -f -c tests/join-population/windows.csv -o tests/join-population/windows-merged.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2-folder
+	./tile-join -c tests/join-population/windows.csv -f -e tests/join-population/windows-merged-folder tests/join-population/macarthur.mbtiles tests/join-population/macarthur2-folder
+	./tile-join -f -o tests/join-population/windows-merged2.mbtiles tests/join-population/windows-merged-folder
+	./tippecanoe-decode tests/join-population/windows-merged.mbtiles > tests/join-population/windows-merged.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/windows-merged2.mbtiles > tests/join-population/windows-merged2.mbtiles.json.check
+	cmp tests/join-population/windows-merged.mbtiles.json.check tests/join-population/windows-merged2.mbtiles.json.check
+	./tile-join -f -o tests/join-population/macarthur-and-macarthur2-merged.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2-folder
+	./tile-join -f -e tests/join-population/macarthur-and-macarthur2-folder tests/join-population/macarthur.mbtiles tests/join-population/macarthur2-folder
+	./tile-join -f -o tests/join-population/macarthur-and-macarthur2-merged2.mbtiles tests/join-population/macarthur-and-macarthur2-folder
+	./tippecanoe-decode tests/join-population/macarthur-and-macarthur2-merged.mbtiles > tests/join-population/macarthur-and-macarthur2-merged.mbtiles.json.check
+	./tippecanoe-decode tests/join-population/macarthur-and-macarthur2-merged2.mbtiles > tests/join-population/macarthur-and-macarthur2-merged2.mbtiles.json.check
+	cmp tests/join-population/macarthur-and-macarthur2-merged.mbtiles.json.check tests/join-population/macarthur-and-macarthur2-merged2.mbtiles.json.check
+	rm tests/join-population/tabblock_06001420.mbtiles tests/join-population/joined.mbtiles tests/join-population/joined-i.mbtiles tests/join-population/joined.mbtiles.json.check tests/join-population/joined-i.mbtiles.json.check tests/join-population/macarthur.mbtiles tests/join-population/merged.mbtiles tests/join-population/merged.mbtiles.json.check  tests/join-population/merged-folder.mbtiles tests/join-population/macarthur2.mbtiles tests/join-population/windows.mbtiles tests/join-population/windows-merged.mbtiles tests/join-population/windows-merged2.mbtiles tests/join-population/windows.mbtiles.json.check tests/join-population/just-macarthur.mbtiles tests/join-population/no-macarthur.mbtiles tests/join-population/just-macarthur.mbtiles.json.check tests/join-population/no-macarthur.mbtiles.json.check tests/join-population/merged-folder.mbtiles.json.check tests/join-population/windows-merged.mbtiles.json.check tests/join-population/windows-merged2.mbtiles.json.check tests/join-population/macarthur-and-macarthur2-merged.mbtiles tests/join-population/macarthur-and-macarthur2-merged2.mbtiles tests/join-population/macarthur-and-macarthur2-merged.mbtiles.json.check tests/join-population/macarthur-and-macarthur2-merged2.mbtiles.json.check
+	rm -rf tests/join-population/raw-merged-folder tests/join-population/tabblock_06001420-folder tests/join-population/macarthur-folder tests/join-population/macarthur2-folder tests/join-population/merged-mbtiles-to-folder tests/join-population/merged-folders-to-folder tests/join-population/windows-merged-folder tests/join-population/macarthur-and-macarthur2-folder
+	# Test renaming of layers
+	./tippecanoe -f -Z5 -z10 -o tests/join-population/macarthur.mbtiles -l macarthur1 tests/join-population/macarthur.json
+	./tippecanoe -f -Z5 -z10 -o tests/join-population/macarthur2.mbtiles -l macarthur2 tests/join-population/macarthur2.json
+	./tile-join -R macarthur1:one --rename-layer=macarthur2:two -f -o tests/join-population/renamed.mbtiles tests/join-population/macarthur.mbtiles tests/join-population/macarthur2.mbtiles
+	./tippecanoe-decode tests/join-population/renamed.mbtiles > tests/join-population/renamed.mbtiles.json.check
+	cmp tests/join-population/renamed.mbtiles.json.check tests/join-population/renamed.mbtiles.json
+	rm -f tests/join-population/renamed.mbtiles.json.check tests/join-population/renamed.mbtiles.json.check tests/join-population/macarthur.mbtiles tests/join-population/macarthur2.mbtiles
+
+join-filter-test:
+	# Comes out different from the direct tippecanoe run because null attributes are lost
+	./tippecanoe -z0 -f -o tests/feature-filter/out/all.mbtiles tests/feature-filter/in.json
+	./tile-join -J tests/feature-filter/filter -f -o tests/feature-filter/out/filtered.mbtiles tests/feature-filter/out/all.mbtiles
+	./tippecanoe-decode tests/feature-filter/out/filtered.mbtiles > tests/feature-filter/out/filtered.json.check
+	cmp tests/feature-filter/out/filtered.json.check tests/feature-filter/out/filtered.json.standard
+	rm -f tests/feature-filter/out/filtered.json.check tests/feature-filter/out/filtered.mbtiles tests/feature-filter/out/all.mbtiles
+
+# Use this target to regenerate the standards that the tests are compared against
+# after making a change that legitimately changes their output
+
+prep-test: $(TESTS)
+
+tests/%.json: Makefile tippecanoe tippecanoe-decode
+	./tippecanoe -f -o $@.check.mbtiles $(subst @,:,$(subst %,/,$(subst _, ,$(patsubst %.json,%,$(word 4,$(subst /, ,$@)))))) $(wildcard $(subst $(SPACE),/,$(wordlist 1,2,$(subst /, ,$@)))/*.json)
+	./tippecanoe-decode $@.check.mbtiles > $@
+	cmp $(patsubst %.check,%,$@) $@
+	rm $@.check.mbtiles

README.md

@@ -1,8 +1,11 @@
 tippecanoe
 ==========
 
-Builds [vector tilesets](https://www.mapbox.com/developers/vector-tiles/) from large collections of [GeoJSON](http://geojson.org/)
-features. This is a tool for [making maps from huge datasets](MADE_WITH.md).
+Builds [vector tilesets](https://www.mapbox.com/developers/vector-tiles/) from large (or small) collections of [GeoJSON](http://geojson.org/) or [Geobuf](https://github.com/mapbox/geobuf) features,
+[like these](MADE_WITH.md).
+
+[![Build Status](https://travis-ci.org/mapbox/tippecanoe.svg)](https://travis-ci.org/mapbox/tippecanoe)
+[![Coverage Status](https://coveralls.io/repos/mapbox/tippecanoe/badge.svg?branch=master&service=github)](https://coveralls.io/github/mapbox/tippecanoe?branch=master)
 
 Intent
 ------
@@ -38,7 +41,7 @@ Usage
 -----
 
 ```sh
-$ tippecanoe -o file.mbtiles [file.json ...]
+$ tippecanoe -o file.mbtiles [options] [file.json file.geobuf ...]
 ```
 
 If no files are specified, it reads GeoJSON from the standard input.
@@ -49,72 +52,275 @@ You can concatenate multiple GeoJSON features or files together,
 and it will parse out the features and ignore whatever other objects
 it encounters.
 
-Options
--------
+Try this first
+--------------
 
-### Naming
+If you aren't sure what options to use, try this:
 
- * -l _name_: Layer name (default "file" if source is file.json or output is file.mbtiles). Only works if there is only one layer.
- * -n _name_: Human-readable name (default file.json)
+```sh
+$ tippecanoe -o out.mbtiles -zg --drop-densest-as-needed in.geojson
+```
 
-### File control
+The `-zg` option will make Tippecanoe choose a maximum zoom level that should be
+high enough to reflect the precision of the original data. (If it turns out still
+not to be as detailed as you want, use `-z` manually with a higher number.)
 
- * -o _file_.mbtiles: Name the output file.
- * -f: Delete the mbtiles file if it already exists instead of giving an error
- * -t _directory_: Put the temporary files in _directory_.
+If the tiles come out too big, the `--drop-densest-as-needed` option will make
+Tippecanoe try dropping what should be the least visible features at each zoom level.
+(If it drops too many features, use `-x` to leave out some feature attributes that
+you didn't really need.)
 
-### Zoom levels and resolution
+Examples
+--------
 
- * -z _zoom_: Base (maxzoom) zoom level (default 14)
- * -Z _zoom_: Lowest (minzoom) zoom level (default 0)
- * -d _detail_: Detail at base zoom level (default 12 at -z14 or higher, or 13 at -z13 or lower. Detail beyond 13 has rendering problems with Mapbox GL.)
- * -D _detail_: Detail at lower zoom levels (default 10, for tile resolution of 1024)
- * -m _detail_: Minimum detail that it will try if tiles are too big at regular detail (default 7)
- * -b _pixels_: Buffer size where features are duplicated from adjacent tiles. Units are "screen pixels"--1/256th of the tile width or height. (default 5)
-
-### Properties
-
- * -x _name_: Exclude the named properties from all features
- * -y _name_: Include the named properties in all features, excluding all those not explicitly named
- * -X: Exclude all properties and encode only geometries
-
-### Point simplification
-
- * -r _rate_: Rate at which dots are dropped at lower zoom levels (default 2.5)
- * -g _gamma_: Rate at which especially dense dots are dropped (default 0, for no effect). A gamma of 2 reduces the number of dots less than a pixel apart to the square root of their original number.
-
-### Doing more
-
- * -ac: Coalesce adjacent line and polygon features that have the same properties
- * -ar: Try reversing the directions of lines to make them coalesce and compress better
- * -ao: Reorder features to put ones with the same properties in sequence, to try to get them to coalesce
- * -al: Let "dot" dropping at lower zooms apply to lines too
-
-### Doing less
-
- * -ps: Don't simplify lines
- * -pf: Don't limit tiles to 200,000 features
- * -pk: Don't limit tiles to 500K bytes
- * -pd: Dynamically drop some fraction of features from large tiles to keep them under the 500K size limit. It will probably look ugly at the tile boundaries.
- * -pi: Preserve the original input order of features as the drawing order instead of ordering geographically. (This is implemented as a restoration of the original order at the end, so that dot-dropping is still geographic, which means it also undoes -ao).
- * -q: Work quietly instead of reporting progress
-
-Example
--------
+Create a tileset of TIGER roads for Alameda County, to zoom level 13, with a custom layer name and description:
 
 ```sh
 $ tippecanoe -o alameda.mbtiles -l alameda -n "Alameda County from TIGER" -z13 tl_2014_06001_roads.json
 ```
 
+Create a tileset of all TIGER roads, at only zoom level 12, but with higher detail than normal,
+with a custom layer name and description, and leaving out the `LINEARID` and `RTTYP` attributes:
+
 ```
 $ cat tiger/tl_2014_*_roads.json | tippecanoe -o tiger.mbtiles -l roads -n "All TIGER roads, one zoom" -z12 -Z12 -d14 -x LINEARID -x RTTYP
 ```
 
+Options
+-------
+
+There are a lot of options. A lot of the time you won't want to use any of them
+other than `-o` _output_`.mbtiles` to name the output file, and probably `-f` to
+delete the file that already exists with that name.
+
+If you aren't sure what the right maxzoom is for your data, `-zg` will guess one for you
+based on the density of features.
+
+If you are mapping point features, you will often want to use `-Bg` to automatically choose
+a base zoom level for dot dropping. If that doesn't work out for you, try
+`-r1 --drop-fraction-as-needed` to turn off the normal dot dropping and instead
+only drop features if the tiles get too big.
+
+If you are mapping points or polygons, you will often want to use `--drop-densest-as-needed`
+to drop some of them if necessary to make the low zoom levels work.
+
+If your features have a lot of attributes, use `-y` to keep only the ones you really need.
+
+If your input is formatted as newline-delimited GeoJSON, use `-P` to make input parsing a lot faster.
+
+### Output tileset
+
+ * `-o` _file_`.mbtiles` or `--output=`_file_`.mbtiles`: Name the output file.
+ * `-e` _directory_ or `--output-to-directory`=_directory_: Write tiles to the specified *directory* instead of to an mbtiles file.
+ * `-f` or `--force`: Delete the mbtiles file if it already exists instead of giving an error
+ * `-F` or `--allow-existing`: Proceed (without deleting existing data) if the metadata or tiles table already exists
+   or if metadata fields can't be set. You probably don't want to use this.
+
+### Tileset description and attribution
+
+ * `-n` _name_ or `--name=`_name_: Human-readable name for the tileset (default file.json)
+ * `-A` _text_ or `--attribution=`_text_: Attribution (HTML) to be shown with maps that use data from this tileset.
+ * `-N` _description_ or `--description=`_description_: Description for the tileset (default file.mbtiles)
+
+### Input files and layer names
+
+ * _name_`.json` or _name_`.geojson`: Read the named GeoJSON input file into a layer called _name_.
+ * _name_`.geobuf` or _name_`.geobuf`: Read the named Geobuf input file into a layer called _name_.
+ * `-l` _name_ or `--layer=`_name_: Use the specified layer name instead of deriving a name from the input filename or output tileset. If there are multiple input files
+   specified, the files are all merged into the single named layer, even if they try to specify individual names with `-L`.
+ * `-L` _name_`:`_file.json_ or `--named-layer=`_name_`:`_file.json_: Specify layer names for individual files. If your shell supports it, you can use a subshell redirect like `-L` _name_`:<(cat dir/*.json)` to specify a layer name for the output of streamed input.
+
+### Parallel processing of input
+
+ * `-P` or `--read-parallel`: Use multiple threads to read different parts of each GeoJSON input file at once.
+   This will only work if the input is line-delimited JSON with each Feature on its
+   own line, because it knows nothing of the top-level structure around the Features. Spurious "EOF" error
+   messages may result otherwise.
+   Performance will be better if the input is a named file that can be mapped into memory
+   rather than a stream that can only be read sequentially.
+
+If the input file begins with the [RFC 8142](https://tools.ietf.org/html/rfc8142) record separator,
+parallel processing of input will be invoked automatically, splitting at record separators rather
+than at all newlines.
+
+Parallel processing will also be automatic if the input file is in Geobuf format.
+
+### Projection of input
+
+ * `-s` _projection_ or `--projection=`_projection_: Specify the projection of the input data. Currently supported are `EPSG:4326` (WGS84, the default) and `EPSG:3857` (Web Mercator). In general you should use WGS84 for your input files if at all possible.
+
+### Zoom levels
+
+ * `-z` _zoom_ or `--maximum-zoom=`_zoom_: Maxzoom: the highest zoom level for which tiles are generated (default 14)
+ * `-zg` or `--maximum-zoom=g`: Guess what is probably a reasonable maxzoom based on the spacing of features.
+ * `-Z` _zoom_ or `--minimum-zoom=`_zoom_: Minzoom: the lowest zoom level for which tiles are generated (default 0)
+ * `-ae` or `--extend-zooms-if-still-dropping`: Increase the maxzoom if features are still being dropped at that zoom level.
+   The detail and simplification options that ordinarily apply only to the maximum zoom level will apply both to the originally
+   specified maximum zoom and to any levels added beyond that.
+
+### Tile resolution
+
+ * `-d` _detail_ or `--full-detail=`_detail_: Detail at max zoom level (default 12, for tile resolution of 2^12=4096)
+ * `-D` _detail_ or `--low-detail=`_detail_: Detail at lower zoom levels (default 12, for tile resolution of 2^12=4096)
+ * `-m` _detail_ or `--minimum-detail=`_detail_: Minimum detail that it will try if tiles are too big at regular detail (default 7)
+
+All internal math is done in terms of a 32-bit tile coordinate system, so 1/(2^32) of the size of Earth,
+or about 1cm, is the smallest distinguishable distance. If _maxzoom_ + _detail_ > 32, no additional
+resolution is obtained than by using a smaller _maxzoom_ or _detail_.
+
+### Filtering feature attributes
+
+ * `-x` _name_ or `--exclude=`_name_: Exclude the named properties from all features
+ * `-y` _name_ or `--include=`_name_: Include the named properties in all features, excluding all those not explicitly named
+ * `-X` or `--exclude-all`: Exclude all properties and encode only geometries
+ * `-T`_attribute_`:`_type_ or `--attribute-type=`_attribute_`:`_type_: Coerce the named feature _attribute_ to be of the specified _type_.
+   The _type_ may be `string`, `float`, `int`, or `bool`.
+   If the type is `bool`, then original attributes of `0` (or, if numeric, `0.0`, etc.), `false`, `null`, or the empty string become `false`, and otherwise become `true`.
+   If the type is `float` or `int` and the original attribute was non-numeric, it becomes `0`.
+   If the type is `int` and the original attribute was floating-point, it is rounded to the nearest integer.
+ * `-j` *filter* or `--feature-filter`=*filter*: Check features against a per-layer filter (as defined in the [Mapbox GL Style Specification](https://www.mapbox.com/mapbox-gl-js/style-spec/#types-filter)) and only include those that match. Any features in layers that have no filter specified will be passed through. Filters for the layer `"*"` apply to all layers.
+ * `-J` *filter-file* or `--feature-filter-file`=*filter-file*: Like `-j`, but read the filter from a file.
+
+Example: to find the Natural Earth countries with low `scalerank` but high `LABELRANK`:
+
+```
+tippecanoe -z5 -o filtered.mbtiles -j '{ "ne_10m_admin_0_countries": [ "all", [ "<", "scalerank", 3 ], [ ">", "LABELRANK", 5 ] ] }' ne_10m_admin_0_countries.geojson
+```
+
+### Dropping a fixed fraction of features by zoom level
+
+ * `-r` _rate_ or `--drop-rate=`_rate_: Rate at which dots are dropped at zoom levels below basezoom (default 2.5).
+   If you use `-rg`, it will guess a drop rate that will keep at most 50,000 features in the densest tile.
+   You can also specify a marker-width with `-rg`*width* to allow fewer features in the densest tile to
+   compensate for the larger marker, or `-rf`*number* to allow at most *number* features in the densest tile.
+ * `-B` _zoom_ or `--base-zoom=`_zoom_: Base zoom, the level at and above which all points are included in the tiles (default maxzoom).
+   If you use `-Bg`, it will guess a zoom level that will keep at most 50,000 features in the densest tile.
+   You can also specify a marker-width with `-Bg`*width* to allow fewer features in the densest tile to
+   compensate for the larger marker, or `-Bf`*number* to allow at most *number* features in the densest tile.
+ * `-al` or `--drop-lines`: Let "dot" dropping at lower zooms apply to lines too
+ * `-ap` or `--drop-polygons`: Let "dot" dropping at lower zooms apply to polygons too
+
+### Dropping a fraction of features to keep under tile size limits
+
+ * `-as` or `--drop-densest-as-needed`: If a tile is too large, try to reduce it to under 500K by increasing the minimum spacing between features. The discovered spacing applies to the entire zoom level.
+ * `-ad` or `--drop-fraction-as-needed`: Dynamically drop some fraction of features from each zoom level to keep large tiles under the 500K size limit. (This is like `-pd` but applies to the entire zoom level, not to each tile.)
+ * `-an` or `--drop-smallest-as-needed`: Dynamically drop the smallest features (physically smallest: the shortest lines or the smallest polygons) from each zoom level to keep large tiles under the 500K size limit. This option will not work for point features.
+ * `-aN` or `--coalesce-smallest-as-needed`: Dynamically combine the smallest features (physically smallest: the shortest lines or the smallest polygons) from each zoom level into other nearby features to keep large tiles under the 500K size limit. This option will not work for point features, and will probably not help very much with LineStrings. It is mostly intended for polygons, to maintain the full original area covered by polygons while still reducing the feature count somehow. The attributes of the small polygons are *not* preserved into the combined features, only their geometry.
+ * `-pd` or `--force-feature-limit`: Dynamically drop some fraction of features from large tiles to keep them under the 500K size limit. It will probably look ugly at the tile boundaries. (This is like `-ad` but applies to each tile individually, not to the entire zoom level.) You probably don't want to use this.
+
+### Dropping tightly overlapping features
+
+ * `-g` _gamma_ or `--gamma=_gamma`_: Rate at which especially dense dots are dropped (default 0, for no effect). A gamma of 2 reduces the number of dots less than a pixel apart to the square root of their original number.
+ * `-aG` or `--increase-gamma-as-needed`: If a tile is too large, try to reduce it to under 500K by increasing the `-g` gamma. The discovered gamma applies to the entire zoom level. You probably want to use `--drop-densest-as-needed` instead.
+
+### Line and polygon simplification
+
+ * `-S` _scale_ or `--simplification=`_scale_: Multiply the tolerance for line and polygon simplification by _scale_. The standard tolerance tries to keep
+   the line or polygon within one tile unit of its proper location. You can probably go up to about 10 without too much visible difference.
+ * `-ps` or `--no-line-simplification`: Don't simplify lines and polygons
+ * `-pS` or `--simplify-only-low-zooms`: Don't simplify lines and polygons at maxzoom (but do simplify at lower zooms)
+ * `-pt` or `--no-tiny-polygon-reduction`: Don't combine the area of very small polygons into small squares that represent their combined area.
+
+### Attempts to improve shared polygon boundaries
+
+ * `-ab` or `--detect-shared-borders`: In the manner of [TopoJSON](https://github.com/mbostock/topojson/wiki/Introduction), detect borders that are shared between multiple polygons and simplify them identically in each polygon. This takes more time and memory than considering each polygon individually.
+ * `-aL` or `--grid-low-zooms`: At all zoom levels below _maxzoom_, snap all lines and polygons to a stairstep grid instead of allowing diagonals. You will also want to specify a tile resolution, probably `-D8`. This option provides a way to display continuous parcel, gridded, or binned data at low zooms without overwhelming the tiles with tiny polygons, since features will either get stretched out to the grid unit or lost entirely, depending on how they happened to be aligned in the original data. You probably don't want to use this.
+
+### Controlling clipping to tile boundaries
+
+ * `-b` _pixels_ or `--buffer=`_pixels_: Buffer size where features are duplicated from adjacent tiles. Units are "screen pixels"—1/256th of the tile width or height. (default 5)
+ * `-pc` or `--no-clipping`: Don't clip features to the size of the tile. If a feature overlaps the tile's bounds or buffer at all, it is included completely. Be careful: this can produce very large tilesets, especially with large polygons.
+ * `-pD` or `--no-duplication`: As with `--no-clipping`, each feature is included intact instead of cut to tile boundaries. In addition, it is included only in a single tile per zoom level rather than potentially in multiple copies. Clients of the tileset must check adjacent tiles (possibly some distance away) to ensure they have all features.
+
+### Reordering features within each tile
+
+ * `-pi` or `--preserve-input-order`: Preserve the original input order of features as the drawing order instead of ordering geographically. (This is implemented as a restoration of the original order at the end, so that dot-dropping is still geographic, which means it also undoes `-ao`).
+ * `-ao` or `--reorder`: Reorder features to put ones with the same properties in sequence, to try to get them to coalesce. You probably don't want to use this.
+ * `-ac` or `--coalesce`: Coalesce adjacent line and polygon features that have the same properties. You probably don't want to use this.
+ * `-ar` or `--reverse`: Try reversing the directions of lines to make them coalesce and compress better. You probably don't want to use this.
+
+### Adding calculated attributes
+
+ * `-ag` or `--calculate-feature-density`: Add a new attribute, `tippecanoe_feature_density`, to each feature, to record how densely features are spaced in that area of the tile. You can use this attribute in the style to produce a glowing effect where points are densely packed. It can range from 0 in the sparsest areas to 255 in the densest.
+
+### Trying to correct bad source geometry
+
+ * `-aw` or `--detect-longitude-wraparound`: Detect when adjacent points within a feature jump to the other side of the world, and try to fix the geometry.
+
+### Setting or disabling tile size limits
+
+ * `-M` _bytes_ or `--maximum-tile-bytes=`_bytes_: Use the specified number of _bytes_ as the maximum compressed tile size instead of 500K.
+ * `-pf` or `--no-feature-limit`: Don't limit tiles to 200,000 features
+ * `-pk` or `--no-tile-size-limit`: Don't limit tiles to 500K bytes
+ * `-pC` or `--no-tile-compression`: Don't compress the PBF vector tile data.
+ * `-pg` or `--no-tile-stats`: Don't generate the `tilestats` row in the tileset metadata. Uploads without [tilestats](https://github.com/mapbox/mapbox-geostats) will take longer to process.
+
+### Temporary storage
+
+ * `-t` _directory_ or `--temporary-directory=`_directory_: Put the temporary files in _directory_.
+   If you don't specify, it will use `/tmp`.
+
+### Progress indicator
+
+ * `-q` or `--quiet`: Work quietly instead of reporting progress
+ * `-v` or `--version`: Report Tippecanoe's version number
+
+### Filters
+
+ * `-C` _command_ or `--prefilter=`_command_: Specify a shell filter command to be run at the start of assembling each tile
+ * `-c` _command_ or `--postfilter=`_command_: Specify a shell filter command to be run at the end of assembling each tile
+
+The pre- and post-filter commands allow you to do optional filtering or transformation on the features of each tile
+as it is created. They are shell commands, run with the zoom level, X, and Y as the `$1`, `$2`, and `$3` arguments.
+Future versions of Tippecanoe may add additional arguments for more context.
+
+The features are provided to the filter
+as a series of newline-delimited GeoJSON objects on the standard input, and `tippecanoe` expects to read another
+set of GeoJSON features from the filter's standard output.
+
+The prefilter receives the features at the highest available resolution, before line simplification,
+polygon topology repair, gamma calculation, dynamic feature dropping, or other internal processing.
+The postfilter receives the features at tile resolution, after simplification, cleaning, and dropping.
+
+The layer name is provided as part of the `tippecanoe` element of the feature and must be passed through
+to keep the feature in its correct layer. In the case of the prefilter, the `tippecanoe` element may also
+contain `index`, `sequence`, and `extent` elements, which must be passed through for internal operations like
+`--drop-densest-as-needed`, `--drop-smallest-as-needed`, and `--preserve-input-order` to work.
+
+#### Examples:
+
+ * Make a tileset of the Natural Earth countries to zoom level 5, and also copy the GeoJSON features
+   to files in a `tiles/z/x/y.geojson` directory hierarchy.
+
+```
+tippecanoe -o countries.mbtiles -z5 -C 'mkdir -p tiles/$1/$2; tee tiles/$1/$2/$3.geojson' ne_10m_admin_0_countries.json
+```
+
+ * Make a tileset of the Natural Earth countries to zoom level 5, but including only those tiles that
+   intersect the [bounding box of Germany](https://www.flickr.com/places/info/23424829).
+   (The `limit-tiles-to-bbox` script is [in the Tippecanoe source directory](filters/limit-tiles-to-bbox).)
+
+```
+tippecanoe -o countries.mbtiles -z5 -C './filters/limit-tiles-to-bbox 5.8662 47.2702 15.0421 55.0581 $*' ne_10m_admin_0_countries.json
+```
+
+ * Make a tileset of TIGER roads in Tippecanoe County, leaving out all but primary and secondary roads (as [classified by TIGER](https://www.census.gov/geo/reference/mtfcc.html)) below zoom level 11.
+
+```
+tippecanoe -o roads.mbtiles -c 'if [ $1 -lt 11 ]; then grep "\"MTFCC\": \"S1[12]00\""; else cat; fi' tl_2016_18157_roads.json
+```
+
+Environment
+-----------
+
+Tippecanoe ordinarily uses as many parallel threads as the operating system claims that CPUs are available.
+You can override this number by setting the `TIPPECANOE_MAX_THREADS` environmental variable.
+
 GeoJSON extension
 -----------------
 
 Tippecanoe defines a GeoJSON extension that you can use to specify the minimum and/or maximum zoom level
-at which an individual feature will be included in the vector tile dataset being produced.
+at which an individual feature will be included in the vector tileset being produced.
 If you have a feature like this:
 
 ```
@@ -131,7 +337,24 @@ If you have a feature like this:
 
 with a `tippecanoe` object specifiying a `maxzoom` of 9 and a `minzoom` of 4, the feature
 will only appear in the vector tiles for zoom levels 4 through 9. Note that the `tippecanoe`
-object belongs to the Feature, not to its `properties`.
+object belongs to the Feature, not to its `properties`. If you specify a `minzoom` for a feature,
+it will be preserved down to that zoom level even if dot-dropping with `-r` would otherwise have
+dropped it.
+
+You can also specify a layer name in the `tippecanoe` object, which will take precedence over
+the filename or name specified using `--layer`, like this:
+
+```
+{
+    "type" : "Feature",
+    "tippecanoe" : { "layer" : "streets" },
+    "properties" : { "FULLNAME" : "N Vasco Rd" },
+    "geometry" : {
+        "type" : "LineString",
+        "coordinates" : [ [ -121.733350, 37.767671 ], [ -121.733600, 37.767483 ], [ -121.733131, 37.766952 ] ]
+    }
+}
+```
 
 Point styling
 -------------
@@ -141,7 +364,7 @@ coordinated with the base zoom level and dot-dropping rate. You can use this she
 calculate the appropriate marker-width at high zoom levels to match the fraction of dots
 that were dropped at low zoom levels.
 
-If you used `-z` to change the base zoom level or `-r` to change the
+If you used `-B` or `-z` to change the base zoom level or `-r` to change the
 dot-dropping rate, replace them in the `basezoom` and `rate` below.
 
     awk 'BEGIN {
@@ -166,7 +389,9 @@ Geometric simplifications
 At every zoom level, line and polygon features are subjected to Douglas-Peucker
 simplification to the resolution of the tile.
 
-For point features, it drops 1/2.5 of the dots for each zoom level above the base.
+For point features, it drops 1/2.5 of the dots for each zoom level above the
+point base zoom (which is normally the same as the `-z` max zoom, but can be
+a different zoom specified with `-B` if you have precise but sparse data).
 I don't know why 2.5 is the appropriate number, but the densities of many different
 data sets fall off at about this same rate. You can use -r to specify a different rate.
 
@@ -178,13 +403,14 @@ For line features, it drops any features that are too small to draw at all.
 This still leaves the lower zooms too dark (and too dense for the 500K tile limit,
 in some places), so I need to figure out an equitable way to throw features away.
 
-Any polygons that are smaller than a minimum area (currently 4 square subpixels) will
+Unless you specify `--no-tiny-polygon-reduction`,
+any polygons that are smaller than a minimum area (currently 4 square subpixels) will
 have their probability diffused, so that some of them will be drawn as a square of
 this minimum size and others will not be drawn at all, preserving the total area that
 all of them should have had together.
 
 Features in the same tile that share the same type and attributes are coalesced
-together into a single geometry. You are strongly encouraged to use -x to exclude
+together into a single geometry if you use `--coalesce`. You are strongly encouraged to use -x to exclude
 any unnecessary properties to reduce wasted file size.
 
 If a tile is larger than 500K, it will try encoding that tile at progressively
@@ -193,18 +419,12 @@ lower resolutions before failing if it still doesn't fit.
 Development
 -----------
 
-Requires protoc and sqlite3. Rebuilding the manpage
+Requires sqlite3 and zlib (should already be installed on MacOS). Rebuilding the manpage
 uses md2man (`gem install md2man`).
 
-MacOS:
-
-    brew install protobuf
-
 Linux:
 
-    sudo apt-get install libprotobuf-dev
-    sudo apt-get install protobuf-compiler
-    sudo apt-get install libsqlite3-dev
+    sudo apt-get install build-essential libsqlite3-dev zlib1g-dev
 
 Then build:
 
@@ -214,6 +434,35 @@ and perhaps
 
     make install
 
+Tippecanoe now requires features from the 2011 C++ standard. If your compiler is older than
+that, you will need to install a newer one. On MacOS, updating to the lastest XCode should
+get you a new enough version of `clang++`. On Linux, you should be able to upgrade `g++` with
+
+```
+sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
+sudo apt-get update -y
+sudo apt-get install -y g++-5
+export CXX=g++-5
+```
+
+Docker Image
+------------
+
+A tippecanoe Docker image can be built from source and executed as a task to
+automatically install dependencies and allow tippecanoe to run on any system
+supported by Docker.
+
+```docker
+$ docker build -t tippecanoe:latest .
+$ docker run -it --rm \
+  -v /tiledata:/data \
+  tippecanoe:latest \
+  tippecanoe --output=/data/output.mbtiles /data/example.geojson
+```
+
+The commands above will build a Docker image from the source and compile the
+latest version. The image supports all tippecanoe flags and options.
+
 Examples
 ------
 
@@ -227,21 +476,64 @@ The name is [a joking reference](http://en.wikipedia.org/wiki/Tippecanoe_and_Tyl
 tile-join
 =========
 
-Tile-join is a tool for joining new attributes from a CSV file to features that
-have already been tiled with tippecanoe. It reads the tiles from an existing .mbtiles
-file, matches them against the records of the CSV, and writes out a new tileset.
+Tile-join is a tool for copying and merging vector mbtiles files and for
+joining new attributes from a CSV file to existing features in them.
+
+It reads the tiles from an
+existing .mbtiles file or a directory of tiles, matches them against the
+records of the CSV (if one is specified), and writes out a new tileset.
+
+If you specify multiple source mbtiles files or source directories of tiles,
+all the sources are read and their combined contents are written to the new
+mbtiles output. If they define the same layers or the same tiles, the layers
+or tiles are merged.
 
 The options are:
 
- * -o *out.mbtiles*: Write the new tiles to the specified .mbtiles file
- * -f: Remove *out.mbtiles* if it already exists
- * -c *match.csv*: Use *match.csv* as the source for new attributes to join to the features. The first line of the file should be the key names; the other lines are values. The first column is the one to match against the existing features; the other columns are the new data to add.
- * -x *key*: Remove attributes of type *key* from the output. You can use this to remove the field you are matching against if you no longer need it after joining, or to remove any other attributes you don't want.
- * -i: Only include features that matched the CSV.
+### Output tileset
 
-Because tile-join just copies the geometries to the new .mbtiles without processing them,
+ * `-o` *out.mbtiles* or `--output=`*out.mbtiles*: Write the new tiles to the specified .mbtiles file.
+ * `-e` *directory* or `--output-to-directory=`*directory*: Write the new tiles to the specified directory instead of to an mbtiles file.
+ * `-f` or `--force`: Remove *out.mbtiles* if it already exists.
+
+### Tileset description and attribution
+
+ * `-A` *attribution* or `--attribution=`*attribution*: Set the attribution string.
+ * `-n` *name* or `--name=`*name*: Set the tileset name.
+ * `-N` *description* or `--description=`*description*: Set the tileset description.
+
+### Layer filtering and naming
+
+ * `-l` *layer* or `--layer=`*layer*: Include the named layer in the output. You can specify multiple `-l` options to keep multiple layers. If you don't specify, they will all be retained.
+ * `-L` *layer* or `--exclude-layer=`*layer*: Remove the named layer from the output. You can specify multiple `-L` options to remove multiple layers.
+ * `-R`*old*`:`*new* or `--rename-layer=`*old*`:`*new*: Rename the layer named *old* to be named *new* instead. You can specify multiple `-R` options to rename multiple layers. Renaming happens before filtering.
+
+### Zoom levels
+
+ * `-z` _zoom_ or `--maximum-zoom=`_zoom_: Don't copy tiles from higher zoom levels than the specified zoom
+ * `-Z` _zoom_ or `--minimum-zoom=`_zoom_: Don't copy tiles from lower zoom levels than the specified zoom
+
+### Merging attributes from a CSV file
+
+ * `-c` *match*`.csv` or `--csv=`*match*`.csv`: Use *match*`.csv` as the source for new attributes to join to the features. The first line of the file should be the key names; the other lines are values. The first column is the one to match against the existing features; the other columns are the new data to add.
+
+### Filtering features and feature attributes
+
+ * `-x` *key* or `--exclude=`*key*: Remove attributes of type *key* from the output. You can use this to remove the field you are matching against if you no longer need it after joining, or to remove any other attributes you don't want.
+ * `-i` or `--if-matched`: Only include features that matched the CSV.
+ * `-j` *filter* or `--feature-filter`=*filter*: Check features against a per-layer filter (as defined in the [Mapbox GL Style Specification](https://www.mapbox.com/mapbox-gl-js/style-spec/#types-filter)) and only include those that match. Any features in layers that have no filter specified will be passed through. Filters for the layer `"*"` apply to all layers.
+ * `-J` *filter-file* or `--feature-filter-file`=*filter-file*: Like `-j`, but read the filter from a file.
+
+### Setting or disabling tile size limits
+
+ * `-pk` or `--no-tile-size-limit`: Don't skip tiles larger than 500K.
+ * `-pC` or `--no-tile-compression`: Don't compress the PBF vector tile data.
+ * `-pg` or `--no-tile-stats`: Don't generate the `tilestats` row in the tileset metadata. Uploads without [tilestats](https://github.com/mapbox/mapbox-geostats) will take longer to process.
+
+Because tile-join just copies the geometries to the new .mbtiles without processing them
+(except to rescale the extents if necessary),
 it doesn't have any of tippecanoe's recourses if the new tiles are bigger than the 500K tile limit.
-If a tile is too big, it is just left out of the new tileset.
+If a tile is too big and you haven't specified `-pk`, it is just left out of the new tileset.
 
 Example
 -------
@@ -288,3 +580,42 @@ Then you can join those populations to the geometries and discard the no-longer-
 ```sh
 ./tile-join -o population.mbtiles -x GEOID10 -c population.csv tl_2010_06001_tabblock10.mbtiles
 ```
+
+tippecanoe-enumerate
+====================
+
+The `tippecanoe-enumerate` utility lists the tiles that an `mbtiles` file defines.
+Each line of the output lists the name of the `mbtiles` file and the zoom, x, and y
+coordinates of one of the tiles. It does basically the same thing as
+
+    select zoom_level, tile_column, (1 << zoom_level) - 1 - tile_row from tiles;
+
+on the file in sqlite3.
+
+tippecanoe-decode
+=================
+
+The `tippecanoe-decode` utility turns vector mbtiles back to GeoJSON. You can use it either
+on an entire file:
+
+    tippecanoe-decode file.mbtiles
+
+or on an individual tile:
+
+    tippecanoe-decode file.mbtiles zoom x y
+    tippecanoe-decode file.vector.pbf zoom x y
+
+If you decode an entire file, you get a nested `FeatureCollection` identifying each
+tile and layer separately. Note that the same features generally appear at all zooms,
+so the output for the file will have many copies of the same features at different
+resolutions.
+
+### Options
+
+ * `-s` _projection_ or `--projection=`*projection*: Specify the projection of the output data. Currently supported are EPSG:4326 (WGS84, the default) and EPSG:3857 (Web Mercator).
+ * `-z` _maxzoom_ or `--maximum-zoom=`*maxzoom*: Specify the highest zoom level to decode from the tileset
+ * `-Z` _minzoom_ or `--minimum-zoom=`*minzoom*: Specify the lowest zoom level to decode from the tileset
+ * `-l` _layer_ or `--layer=`*layer*: Decode only layers with the specified names. (Multiple `-l` options can be specified.)
+ * `-c` or `--tag-layer-and-zoom`: Include each feature's layer and zoom level as part of its `tippecanoe` object rather than as a FeatureCollection wrapper
+ * `-S` or `--stats`: Just report statistics about each tile's size and the number of features in it, as a JSON structure.
+ * `-f` or `--force`: Decode tiles even if polygon ring order or closure problems are detected

catch/LICENSE_1_0.txt

@@ -1,5 +1,4 @@
 Boost Software License - Version 1.0 - August 17th, 2003
-http://www.boost.org/LICENSE_1_0.txt
 
 Permission is hereby granted, free of charge, to any person or organization
 obtaining a copy of the software and accompanying documentation covered by
@@ -21,4 +20,4 @@ FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
 SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
 FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
-DEALINGS IN THE SOFTWARE.
+DEALINGS IN THE SOFTWARE.

clip.c

@@ -1,84 +0,0 @@
-#include "clip.h"
-
-#define INSIDE 0
-#define LEFT 1
-#define RIGHT 2
-#define BOTTOM 4
-#define TOP 8
-
-static int computeOutCode(double x, double y, double xmin, double ymin, double xmax, double ymax) {
-	int code = INSIDE;
-
-	if (x < xmin) {
-		code |= LEFT;
-	} else if (x > xmax) {
-		code |= RIGHT;
-	}
-
-	if (y < ymin) {
-		code |= BOTTOM;
-	} else if (y > ymax) {
-		code |= TOP;
-	}
-
-	return code;
-}
-
-int clip(double *x0, double *y0, double *x1, double *y1, double xmin, double ymin, double xmax, double ymax) {
-	int outcode0 = computeOutCode(*x0, *y0, xmin, ymin, xmax, ymax);
-	int outcode1 = computeOutCode(*x1, *y1, xmin, ymin, xmax, ymax);
-	int accept = 0;
-	int changed = 0;
-
-	while (1) {
-		if (!(outcode0 | outcode1)) {  // Bitwise OR is 0. Trivially accept and get out of loop
-			accept = 1;
-			break;
-		} else if (outcode0 & outcode1) {  // Bitwise AND is not 0. Trivially reject and get out of loop
-			break;
-		} else {
-			// failed both tests, so calculate the line segment to clip
-			// from an outside point to an intersection with clip edge
-			double x = *x0, y = *y0;
-
-			// At least one endpoint is outside the clip rectangle; pick it.
-			int outcodeOut = outcode0 ? outcode0 : outcode1;
-
-			// Now find the intersection point;
-			// use formulas y = y0 + slope * (x - x0), x = x0 + (1 / slope) * (y - y0)
-			if (outcodeOut & TOP) {  // point is above the clip rectangle
-				x = *x0 + (*x1 - *x0) * (ymax - *y0) / (*y1 - *y0);
-				y = ymax;
-			} else if (outcodeOut & BOTTOM) {  // point is below the clip rectangle
-				x = *x0 + (*x1 - *x0) * (ymin - *y0) / (*y1 - *y0);
-				y = ymin;
-			} else if (outcodeOut & RIGHT) {  // point is to the right of clip rectangle
-				y = *y0 + (*y1 - *y0) * (xmax - *x0) / (*x1 - *x0);
-				x = xmax;
-			} else if (outcodeOut & LEFT) {  // point is to the left of clip rectangle
-				y = *y0 + (*y1 - *y0) * (xmin - *x0) / (*x1 - *x0);
-				x = xmin;
-			}
-
-			// Now we move outside point to intersection point to clip
-			// and get ready for next pass.
-			if (outcodeOut == outcode0) {
-				*x0 = x;
-				*y0 = y;
-				outcode0 = computeOutCode(*x0, *y0, xmin, ymin, xmax, ymax);
-				changed = 1;
-			} else {
-				*x1 = x;
-				*y1 = y;
-				outcode1 = computeOutCode(*x1, *y1, xmin, ymin, xmax, ymax);
-				changed = 1;
-			}
-		}
-	}
-
-	if (accept == 0) {
-		return 0;
-	} else {
-		return changed + 1;
-	}
-}

clip.h

@@ -1 +0,0 @@
-int clip(double *x0, double *y0, double *x1, double *y1, double xmin, double ymin, double xmax, double ymax);

clipper/README

@@ -1,407 +0,0 @@
-=====================================================================
-Clipper Change Log
-=====================================================================
-v6.2.1 (31 October 2014) Rev 482
-* Bugfix in ClipperOffset.Execute where the Polytree.IsHole property 
-  was returning incorrect values with negative offsets
-* Very minor improvement to join rounding in ClipperOffset
-* Fixed CPP OpenGL demo.
-
-v6.2.0 (17 October 2014) Rev 477
-* Numerous minor bugfixes, too many to list. 
-  (See revisions 454-475 in Sourceforge Repository)
-* The ZFillFunction (custom callback function) has had its parameters 
-  changed. 
-* Curves demo removed (temporarily).
-* Deprecated functions have been removed. 
-
-v6.1.5 (26 February 2014) Rev 460
-* Improved the joining of output polygons sharing a common edge 
-  when those common edges are horizontal.
-* Fixed a bug in ClipperOffset.AddPath() which would produce
-  incorrect solutions when open paths were added before closed paths.
-* Minor code tidy and performance improvement
-
-v6.1.4 (6 February 2014)
-* Fixed bugs in MinkowskiSum
-* Fixed minor bug when using Clipper.ForceSimplify.
-* Modified use_xyz callback so that all 4 vertices around an
-  intersection point are now passed to the callback function.
-
-v6.1.3a (22 January 2014) Rev 453
-* Fixed buggy PointInPolygon function (C++ and C# only). 
-  Note this bug only affected the newly exported function, the 
-  internal PointInPolygon function used by Clipper was OK.
- 
-v6.1.3 (19 January 2014) Rev 452
-* Fixed potential endless loop condition when adding open 
-  paths to Clipper.
-* Fixed missing implementation of SimplifyPolygon function 
-  in C++ code.
-* Fixed incorrect upper range constant for polygon coordinates 
-  in Delphi code.
-* Added PointInPolygon function. 
-* Overloaded MinkowskiSum function to accommodate multi-contour 
-  paths.  
-
-v6.1.2 (15 December 2013) Rev 444
-* Fixed broken C++ header file.
-* Minor improvement to joining polygons.
-
-v6.1.1 (13 December 2013) Rev 441
-* Fixed a couple of bugs affecting open paths that could 
-  raise unhandled exceptions.
-  
-v6.1.0 (12 December 2013)
-* Deleted: Previously deprecated code has been removed. 
-* Modified: The OffsetPaths function is now deprecated as it has 
-  been replaced by the ClipperOffset class which is much more 
-  flexible. 
-* Bugfixes: Several minor bugs have been fixed including 
-  occasionally an incorrect nesting within the PolyTree structure.
-
-v6.0.0 (30 October 2013)
-* Added: Open path (polyline) clipping. A new 'Curves' demo 
-  application showcases this (see the 'Curves' directory). 
-* Update: Major improvement in the merging of 
-  shared/collinear edges in clip solutions (see Execute). 
-* Added: The IntPoint structure now has an optional 'Z' member. 
-  (See the precompiler directive use_xyz.) 
-* Added: Users can now force Clipper to use 32bit integers 
-  (via the precompiler directive use_int32) instead of using 
-  64bit integers.
-* Modified: To accommodate open paths, the Polygon and Polygons 
-  structures have been renamed Path and Paths respectively. The 
-  AddPolygon and AddPolygons methods of the ClipperBase class 
-  have been renamed AddPath and AddPaths respectively. Several 
-  other functions have been similarly renamed. 
-* Modified: The PolyNode Class has a new IsOpen property. 
-* Modified: The Clipper class has a new ZFillFunction property. 
-* Added: MinkowskiSum and MinkowskiDiff functions added. 
-* Added: Several other new functions have been added including 
-  PolyTreeToPaths, OpenPathsFromPolyTree and ClosedPathsFromPolyTree. 
-* Added: The Clipper constructor now accepts an optional InitOptions 
-  parameter to simplify setting properties. 
-* Bugfixes: Numerous minor bugs have been fixed. 
-* Deprecated: Version 6 is a major upgrade from previous versions 
-  and quite a number of changes have been made to exposed structures 
-  and functions. To minimize inconvenience to existing library users, 
-  some code has been retained and some added to maintain backward 
-  compatibility. However, because this code will be removed in a 
-  future update, it has been marked as deprecated and a precompiler 
-  directive use_deprecated has been defined.
-
-v5.1.6 (23 May 2013)
-* BugFix: CleanPolygon function was buggy.
-* Changed: The behaviour of the 'miter' JoinType has been 
-  changed so that when squaring occurs, it's no longer 
-  extended up to the miter limit but is squared off at 
-  exactly 'delta' units. (This improves the look of mitering 
-  with larger limits at acute angles.) 
-* Added: New OffsetPolyLines function
-* Update: Minor code refactoring and optimisations
-
-v5.1.5 (5 May 2013)
-* Added: ForceSimple property to Clipper class
-* Update: Improved documentation  
-
-v5.1.4 (24 March 2013)
-* Update: CleanPolygon function enhanced.
-* Update: Documentation improved.  
-
-v5.1.3 (14 March 2013)
-* Bugfix: Minor bugfixes.
-* Update: Documentation significantly improved.  
-
-v5.1.2 (26 February 2013)
-* Bugfix: PolyNode class was missing a constructor. 
-* Update: The MiterLimit parameter in the OffsetPolygons 
-  function has been renamed Limit and can now also be used to 
-  limit the number of vertices used to construct arcs when 
-  JoinType is set to jtRound.
-
-v5.1.0 (17 February 2013)
-* Update: ExPolygons has been replaced with the PolyTree & 
-  PolyNode classes to more fully represent the parent-child 
-  relationships of the polygons returned by Clipper. 
-* Added: New CleanPolygon and CleanPolygons functions. 
-* Bugfix: Another orientation bug fixed.
-
-v5.0.2 - 30 December 2012
-* Bugfix: Significant fixes in and tidy of the internal 
-  Int128 class (which is used only when polygon coordinate 
-  values are greater than ±0x3FFFFFFF (~1.07e9)). 
-* Update: The Area algorithm has been updated and is faster. 
-* Update: Documentation updates. The newish but undocumented 
-  'CheckInputs' parameter of the OffsetPolygons function has been 
-  renamed 'AutoFix' and documented too. The comments on rounding 
-  have also been improved (ie clearer and expanded).
-
-v4.10.0 - 25 December 2012
-* Bugfix: Orientation bugs should now be resolved (finally!).
-* Bugfix: Bug in Int128 class
-
-v4.9.8 - 2 December 2012
-* Bugfix: Further fixes to rare Orientation bug.
-
-v4.9.7 - 29 November 2012
-* Bugfix: Bug that very rarely returned the wrong polygon 
-  orientation.
-* Bugfix: Obscure bug affecting OffsetPolygons when using 
-  jtRound for the JoinType parameter and when polygons also
-  contain very large coordinate values (> +/-100000000000).
-
-v4.9.6 - 9 November 2012
-* Bugfix: Another obscure bug related to joining polygons.
-
-v4.9.4 - 2 November 2012
-* Bugfix: Bugs in Int128 class occasionally causing 
-  wrong orientations.
-* Bugfix: Further fixes related to joining polygons.
-
-v4.9.0 - 9 October 2012
-* Bugfix: Obscure bug related to joining polygons.
-
-v4.8.9 - 25 September 2012
-* Bugfix: Obscure bug related to precision of intersections.
-          
-v4.8.8 - 30 August 2012
-* Bugfix: Fixed bug in OffsetPolygons function introduced in 
-  version 4.8.5.
-
-v4.8.7 - 24 August 2012
-* Bugfix: ReversePolygon function in C++ translation was broken.
-* Bugfix: Two obscure bugs affecting orientation fixed too.
-
-v4.8.6 - 11 August 2012
-* Bugfix: Potential for memory overflow errors when using 
-  ExPolygons structure.
-* Bugfix: The polygon coordinate range has been reduced to 
-  +/- 0x3FFFFFFFFFFFFFFF (4.6e18).
-* Update: ReversePolygons function was misnamed ReversePoints in C++.
-* Update: SimplifyPolygon function now takes a PolyFillType parameter.
-          
-v4.8.5 - 15 July 2012
-* Bugfix: Potential for memory overflow errors in OffsetPolygons().
-
-v4.8.4 - 1 June 2012
-* Bugfix: Another obscure bug affecting ExPolygons structure.
-
-v4.8.3 - 27 May 2012
-* Bugfix: Obscure bug causing incorrect removal of a vertex.
-
-v4.8.2 - 21 May 2012
-* Bugfix: Obscure bug could cause an exception when using 
-  ExPolygon structure.
-
-v4.8.1 - 12 May 2012
-* Update: Cody tidy and minor bug fixes.
-
-v4.8.0 - 30 April 2012
-* Bugfix: Occasional errors in orientation fixed. 
-* Update: Added notes on rounding to the documentation. 
-
-v4.7.6 - 11 April 2012
-* Fixed a bug in Orientation function (affecting C# translations only).
-* Minor documentation update.
-
-v4.7.5 - 28 March 2012
-* Bugfix: Fixed a recently introduced bug that occasionally caused an 
-  unhandled exception in C++ and C# translations. 
-
-v4.7.4 - 15 March 2012
-* Bugfix: Another minor bugfix.
-
-v4.7.2 - 4 March 2012
-* Bugfix: Fixed bug introduced in ver 4.7 which sometimes caused 
-  an exception if ExPolygon structure was passed to Clipper's 
-  Execute method. 
-
-v4.7.1 - 3 March 2012
-* Bugfix: Rare crash when JoinCommonEdges joined polygons that 
-  'cancelled' each other. 
-* Bugfix: Clipper's internal Orientation method occasionally 
-  returned wrong result. 
-* Update: Improved C# code (thanks to numerous excellent suggestions 
-  from David Piepgrass) 
-
-v4.7 - 10 February 2012
-* Improved the joining of output polygons sharing a common edge.
-
-v4.6.6 - 3 February 2012
-* Bugfix: Another obscure bug occasionally causing incorrect 
-  polygon orientation. 
-
-v4.6.5 - 17 January 2012
-* Bugfix: Obscure bug occasionally causing incorrect hole 
-  assignment in ExPolygon structure. 
-
-v4.6.4 - 8 November 2011
-* Added: SimplifyPolygon and SimplifyPolygons functions.
-
-v4.6.3 - 11 November 2011
-* Bugfix: Fixed another minor mitering bug in OffsetPolygons.
-
-v4.6.2 - 10 November 2011
-* Bugfix: Fixed a rare bug in the orientation of polygons 
-  returned by Clipper's Execute() method.
-* Bugfix: Previous update introduced a mitering bug in the
-  OffsetPolygons function.
-
-v4.6 - 29 October 2011
-* Added: Support for Positive and Negative polygon fill 
-  types (in addition to the EvenOdd and NonZero fill types).
-* Bugfix: The OffsetPolygons function was generating the 
-  occasional artefact when 'shrinking' polygons.
-
-v4.5.5 - 8 October 2011
-* Bugfix: Fixed an obscure bug in Clipper's JoinCommonEdges 
-  method. 
-* Update: Replaced IsClockwise function with Orientation 
-  function. The orientation issues affecting OffsetPolygons 
-  should now be finally resolved.
-* Change: The Area function once again returns a signed value.
- 
-v4.5.1 - 28 September 2011
-* Deleted: The UseFullCoordinateRange property has been 
-  deleted since integer range is now managed implicitly. 
-* BugFix: Minor bug in OffsetPolygon mitering. 
-* Change: C# JoinType enum moved from Clipper class to 
-  ClipperLib namespace. 
-* Change: The Area function now returns the absolute area 
-  (irrespective of orientation). 
-* Change: The IsClockwise function now requires a second 
-  parameter - YAxisPositiveUpward - to accommodate displays 
-  with Y-axis oriented in either direction
-
-v4.4.4 - 10 September 2011
-* Change: Deleted jtButt from JoinType (used by the 
-  OffsetPolygons function). 
-* BugFix: Fixed another minor bug in OffsetPolygons function. 
-* Update: Further improvements to the help file
-
-v4.4.3 - 29 August 2011
-* BugFix: fixed a minor rounding issue in OffsetPolygons 
-  function (affected C++ & C# translations). 
-* BugFix: fixed a minor bug in OffsetPolygons' function 
-  declaration (affected C++ translation only). 
-* Change: 'clipper' namespace changed to 'ClipperLib' 
-  namespace in both C++ and C# code to remove the ambiguity 
-  between the Clipper class and the namespace. (This also 
-  required numerous updates to the accompanying demos.)
-
-v4.4.2 - 26 August 2011
-* BugFix: minor bugfixes in Clipper. 
-* Update: the OffsetPolygons function has been significantly 
-  improved by offering 4 different join styles. 
-
-v4.4.0 - 6 August 2011
-* BugFix: A number of minor bugs have been fixed that mostly 
-  affected the new ExPolygons structure. 
-
-v4.3.0 - 17 June 2011
-* New: ExPolygons structure that explicitly associates 'hole' 
-  polygons with their 'outer' container polygons.
-* New: Execute method overloaded so the solution parameter 
-  can now be either Polygons or ExPolygons.  
-* BugFix: Fixed a rare bug in solution polygons orientation. 
-
-v4.2.8 - 21 May 2011
-* Update: JoinCommonEdges() improved once more. 
-* BugFix: Several minor bugs fixed. 
-
-v4.2.6 - 1 May 2011
-* Bugfix: minor bug in SlopesEqual function.
-* Update: Merging of output polygons sharing common edges 
-  has been significantly inproved
-
-v4.2.4 - 26 April 2011
-  Input polygon coordinates can now contain the full range of 
-  signed 64bit integers (ie +/-9,223,372,036,854,775,807). This 
-  means that floating point values can be converted to and from 
-  Clipper's 64bit integer coordinates structure (IntPoint) and  
-  still retain a precision of up to 18 decimal places. However, 
-  since the large-integer math that supports this expanded range 
-  imposes a small cost on performance (~15%), a new property 
-  UseFullCoordinateRange has been added to the Clipper class to 
-  allow users the choice of whether or not to use this expanded 
-  coordinate range. If this property is disabled, coordinate values 
-  are restricted to +/-1,500,000,000.
-
-v4.2 - 12 April 2011
-  JoinCommonEdges() code significantly improved plus other minor 
-  improvements.
-
-v4.1.2 - 9 April 2011
-* Update: Minor code tidy. 
-* Bugfix: Possible endless loop in JoinCommonEdges() in clipper.pas.
-
-v4.1.1 - 8 April 2011
-* Update: All polygon coordinates are now stored as 64bit integers
-  (though they're still restricted to range -1.5e9 to +1.5e9 pending 
-  the inclusion of code supporting 64bit math).
-* Change: AddPolygon and AddPolygons methods now return boolean 
-  values. 
-* Bugfix: Bug in JoinCommonEdges() caused potential endless loop. 
-* Bugfix: Bug in IsClockwise(). (C++ code only)
-
-v4.0 - 5 April 2011
-* Clipper 4 is a major rewrite of earlier versions. The biggest 
-  change is that floating point values are no longer used, 
-  except for the storing of edge slope values. The main benefit 
-  of this is the issue of numerical robustness has been 
-  addressed. Due to other major code improvements Clipper v4 
-  is approximately 40% faster than Clipper v3. 
-* The AddPolyPolygon method has been renamed to AddPolygons. 
-* The IgnoreOrientation property has been removed. 
-* The clipper_misc library has been merged back into the 
-  main clipper library.
-  
-v3.1.0 - 17 February 2011
-* Bugfix: Obscure bug in TClipperBase.SetDx method that caused 
-  problems with very small edges ( edges <1/1000th pixel in size).
-  
-v3.0.3 - 9 February 2011
-* Bugfix: Significant bug, but only in C# code.
-* Update: Minor refactoring.
-
-v3.0 - 31 January 2011
-* Update: Major rewrite of the portion of code that calculates 
-  the output polygons' orientation.
-* Update: Help file significantly improved.
-* Change: Renamed ForceOrientation property to IgnoreOrientation. 
-  If the orientation of output polygons is not important, or can 
-  be managed separately, clipping routines can be sped up by about 
-  60% by setting IgnoreOrientation to true. Defaults to false.
-* Change: The OffsetPolygon and Area functions have been moved to 
-  the new unit - clipper_misc. 
-
-2.99 - 15 January 2011
-* Bugfix: Obscure bug in AddPolygon method could cause an endless loop. 
-
-2.8 - 20 November 2010
-* Updated: Output polygons which previously shared a common 
-  edge are now merged. 
-* Changed: The orientation of outer polygons is now clockwise 
-  when the display's Y axis is positive downwards (as is 
-  typical for most Windows applications). Inner polygons 
-  (holes) have the opposite orientation.
-* Added: Support module for Cairo Graphics Library (with demo). 
-* Updated: C# and C++ demos.
-
-2.522 - 15 October 2010
-* Added C# translation (thanks to Olivier Lejeune) and 
-  a link to Ruby bindings (thanks to Mike Owens).
-
-2.0 - 30 July 2010
-* Clipper now clips using both the Even-Odd (alternate) and 
-  Non-Zero (winding) polygon filling rules. (Previously Clipper 
-  assumed the Even-Odd rule for polygon filling.)
-  
-1.4c - 16 June 2010
-* Added C++ support for AGG graphics library 
-  
-1.2s - 2 June 2010
-* Added C++ translation of clipper.pas
-
-1.0 - 9 May 2010

clipper/clipper.hpp

@@ -1,395 +0,0 @@
-/*******************************************************************************
-*                                                                              *
-* Author    :  Angus Johnson                                                   *
-* Version   :  6.2.1                                                           *
-* Date      :  31 October 2014                                                 *
-* Website   :  http://www.angusj.com                                           *
-* Copyright :  Angus Johnson 2010-2014                                         *
-*                                                                              *
-* License:                                                                     *
-* Use, modification & distribution is subject to Boost Software License Ver 1. *
-* http://www.boost.org/LICENSE_1_0.txt                                         *
-*                                                                              *
-* Attributions:                                                                *
-* The code in this library is an extension of Bala Vatti's clipping algorithm: *
-* "A generic solution to polygon clipping"                                     *
-* Communications of the ACM, Vol 35, Issue 7 (July 1992) pp 56-63.             *
-* http://portal.acm.org/citation.cfm?id=129906                                 *
-*                                                                              *
-* Computer graphics and geometric modeling: implementation and algorithms      *
-* By Max K. Agoston                                                            *
-* Springer; 1 edition (January 4, 2005)                                        *
-* http://books.google.com/books?q=vatti+clipping+agoston                       *
-*                                                                              *
-* See also:                                                                    *
-* "Polygon Offsetting by Computing Winding Numbers"                            *
-* Paper no. DETC2005-85513 pp. 565-575                                         *
-* ASME 2005 International Design Engineering Technical Conferences             *
-* and Computers and Information in Engineering Conference (IDETC/CIE2005)      *
-* September 24-28, 2005 , Long Beach, California, USA                          *
-* http://www.me.berkeley.edu/~mcmains/pubs/DAC05OffsetPolygon.pdf              *
-*                                                                              *
-*******************************************************************************/
-
-#ifndef clipper_hpp
-#define clipper_hpp
-
-#define CLIPPER_VERSION "6.2.0"
-
-//use_int32: When enabled 32bit ints are used instead of 64bit ints. This
-//improve performance but coordinate values are limited to the range +/- 46340
-//#define use_int32
-
-//use_xyz: adds a Z member to IntPoint. Adds a minor cost to perfomance.
-//#define use_xyz
-
-//use_lines: Enables line clipping. Adds a very minor cost to performance.
-//#define use_lines
-  
-//use_deprecated: Enables temporary support for the obsolete functions
-//#define use_deprecated  
-
-#include <vector>
-#include <set>
-#include <stdexcept>
-#include <cstring>
-#include <cstdlib>
-#include <ostream>
-#include <functional>
-#include <queue>
-
-namespace ClipperLib {
-
-enum ClipType { ctIntersection, ctUnion, ctDifference, ctXor };
-enum PolyType { ptSubject, ptClip };
-//By far the most widely used winding rules for polygon filling are
-//EvenOdd & NonZero (GDI, GDI+, XLib, OpenGL, Cairo, AGG, Quartz, SVG, Gr32)
-//Others rules include Positive, Negative and ABS_GTR_EQ_TWO (only in OpenGL)
-//see http://glprogramming.com/red/chapter11.html
-enum PolyFillType { pftEvenOdd, pftNonZero, pftPositive, pftNegative };
-
-#ifdef use_int32
-  typedef int cInt;
-  static cInt const loRange = 0x7FFF;
-  static cInt const hiRange = 0x7FFF;
-#else
-  typedef signed long long cInt;
-  static cInt const loRange = 0x3FFFFFFF;
-  static cInt const hiRange = 0x3FFFFFFFFFFFFFFFLL;
-  typedef signed long long long64;     //used by Int128 class
-  typedef unsigned long long ulong64;
-
-#endif
-
-struct IntPoint {
-  cInt X;
-  cInt Y;
-#ifdef use_xyz
-  cInt Z;
-  IntPoint(cInt x = 0, cInt y = 0, cInt z = 0): X(x), Y(y), Z(z) {};
-#else
-  IntPoint(cInt x = 0, cInt y = 0): X(x), Y(y) {};
-#endif
-
-  friend inline bool operator== (const IntPoint& a, const IntPoint& b)
-  {
-    return a.X == b.X && a.Y == b.Y;
-  }
-  friend inline bool operator!= (const IntPoint& a, const IntPoint& b)
-  {
-    return a.X != b.X  || a.Y != b.Y; 
-  }
-};
-//------------------------------------------------------------------------------
-
-typedef std::vector< IntPoint > Path;
-typedef std::vector< Path > Paths;
-
-inline Path& operator <<(Path& poly, const IntPoint& p) {poly.push_back(p); return poly;}
-inline Paths& operator <<(Paths& polys, const Path& p) {polys.push_back(p); return polys;}
-
-std::ostream& operator <<(std::ostream &s, const IntPoint &p);
-std::ostream& operator <<(std::ostream &s, const Path &p);
-std::ostream& operator <<(std::ostream &s, const Paths &p);
-
-struct DoublePoint
-{
-  double X;
-  double Y;
-  DoublePoint(double x = 0, double y = 0) : X(x), Y(y) {}
-  DoublePoint(IntPoint ip) : X((double)ip.X), Y((double)ip.Y) {}
-};
-//------------------------------------------------------------------------------
-
-#ifdef use_xyz
-typedef void (*ZFillCallback)(IntPoint& e1bot, IntPoint& e1top, IntPoint& e2bot, IntPoint& e2top, IntPoint& pt);
-#endif
-
-enum InitOptions {ioReverseSolution = 1, ioStrictlySimple = 2, ioPreserveCollinear = 4};
-enum JoinType {jtSquare, jtRound, jtMiter};
-enum EndType {etClosedPolygon, etClosedLine, etOpenButt, etOpenSquare, etOpenRound};
-
-class PolyNode;
-typedef std::vector< PolyNode* > PolyNodes;
-
-class PolyNode 
-{ 
-public:
-    PolyNode();
-    virtual ~PolyNode(){};
-    Path Contour;
-    PolyNodes Childs;
-    PolyNode* Parent;
-    PolyNode* GetNext() const;
-    bool IsHole() const;
-    bool IsOpen() const;
-    int ChildCount() const;
-private:
-    unsigned Index; //node index in Parent.Childs
-    bool m_IsOpen;
-    JoinType m_jointype;
-    EndType m_endtype;
-    PolyNode* GetNextSiblingUp() const;
-    void AddChild(PolyNode& child);
-    friend class Clipper; //to access Index
-    friend class ClipperOffset; 
-};
-
-class PolyTree: public PolyNode
-{ 
-public:
-    ~PolyTree(){Clear();};
-    PolyNode* GetFirst() const;
-    void Clear();
-    int Total() const;
-private:
-    PolyNodes AllNodes;
-    friend class Clipper; //to access AllNodes
-};
-
-bool Orientation(const Path &poly);
-double Area(const Path &poly);
-int PointInPolygon(const IntPoint &pt, const Path &path);
-
-void SimplifyPolygon(const Path &in_poly, Paths &out_polys, PolyFillType fillType = pftEvenOdd);
-void SimplifyPolygons(const Paths &in_polys, Paths &out_polys, PolyFillType fillType = pftEvenOdd);
-void SimplifyPolygons(Paths &polys, PolyFillType fillType = pftEvenOdd);
-
-void CleanPolygon(const Path& in_poly, Path& out_poly, double distance = 1.415);
-void CleanPolygon(Path& poly, double distance = 1.415);
-void CleanPolygons(const Paths& in_polys, Paths& out_polys, double distance = 1.415);
-void CleanPolygons(Paths& polys, double distance = 1.415);
-
-void MinkowskiSum(const Path& pattern, const Path& path, Paths& solution, bool pathIsClosed);
-void MinkowskiSum(const Path& pattern, const Paths& paths, Paths& solution, bool pathIsClosed);
-void MinkowskiDiff(const Path& poly1, const Path& poly2, Paths& solution);
-
-void PolyTreeToPaths(const PolyTree& polytree, Paths& paths);
-void ClosedPathsFromPolyTree(const PolyTree& polytree, Paths& paths);
-void OpenPathsFromPolyTree(PolyTree& polytree, Paths& paths);
-
-void ReversePath(Path& p);
-void ReversePaths(Paths& p);
-
-struct IntRect { cInt left; cInt top; cInt right; cInt bottom; };
-
-//enums that are used internally ...
-enum EdgeSide { esLeft = 1, esRight = 2};
-
-//forward declarations (for stuff used internally) ...
-struct TEdge;
-struct IntersectNode;
-struct LocalMinimum;
-struct Scanbeam;
-struct OutPt;
-struct OutRec;
-struct Join;
-
-typedef std::vector < OutRec* > PolyOutList;
-typedef std::vector < TEdge* > EdgeList;
-typedef std::vector < Join* > JoinList;
-typedef std::vector < IntersectNode* > IntersectList;
-
-//------------------------------------------------------------------------------
-
-//ClipperBase is the ancestor to the Clipper class. It should not be
-//instantiated directly. This class simply abstracts the conversion of sets of
-//polygon coordinates into edge objects that are stored in a LocalMinima list.
-class ClipperBase
-{
-public:
-  ClipperBase();
-  virtual ~ClipperBase();
-  bool AddPath(const Path &pg, PolyType PolyTyp, bool Closed);
-  bool AddPaths(const Paths &ppg, PolyType PolyTyp, bool Closed);
-  virtual void Clear();
-  IntRect GetBounds();
-  bool PreserveCollinear() {return m_PreserveCollinear;};
-  void PreserveCollinear(bool value) {m_PreserveCollinear = value;};
-protected:
-  void DisposeLocalMinimaList();
-  TEdge* AddBoundsToLML(TEdge *e, bool IsClosed);
-  void PopLocalMinima();
-  virtual void Reset();
-  TEdge* ProcessBound(TEdge* E, bool IsClockwise);
-  void DoMinimaLML(TEdge* E1, TEdge* E2, bool IsClosed);
-  TEdge* DescendToMin(TEdge *&E);
-  void AscendToMax(TEdge *&E, bool Appending, bool IsClosed);
-
-  typedef std::vector<LocalMinimum> MinimaList;
-  MinimaList::iterator m_CurrentLM;
-  MinimaList           m_MinimaList;
-
-  bool              m_UseFullRange;
-  EdgeList          m_edges;
-  bool             m_PreserveCollinear;
-  bool             m_HasOpenPaths;
-};
-//------------------------------------------------------------------------------
-
-class Clipper : public virtual ClipperBase
-{
-public:
-  Clipper(int initOptions = 0);
-  ~Clipper();
-  bool Execute(ClipType clipType,
-    Paths &solution,
-    PolyFillType subjFillType = pftEvenOdd,
-    PolyFillType clipFillType = pftEvenOdd);
-  bool Execute(ClipType clipType,
-    PolyTree &polytree,
-    PolyFillType subjFillType = pftEvenOdd,
-    PolyFillType clipFillType = pftEvenOdd);
-  bool ReverseSolution() {return m_ReverseOutput;};
-  void ReverseSolution(bool value) {m_ReverseOutput = value;};
-  bool StrictlySimple() {return m_StrictSimple;};
-  void StrictlySimple(bool value) {m_StrictSimple = value;};
-  //set the callback function for z value filling on intersections (otherwise Z is 0)
-#ifdef use_xyz
-  void ZFillFunction(ZFillCallback zFillFunc);
-#endif
-protected:
-  void Reset();
-  virtual bool ExecuteInternal();
-private:
-  PolyOutList       m_PolyOuts;
-  JoinList          m_Joins;
-  JoinList          m_GhostJoins;
-  IntersectList     m_IntersectList;
-  ClipType          m_ClipType;
-  typedef std::priority_queue<cInt> ScanbeamList;
-  ScanbeamList      m_Scanbeam;
-  TEdge           *m_ActiveEdges;
-  TEdge           *m_SortedEdges;
-  bool             m_ExecuteLocked;
-  PolyFillType     m_ClipFillType;
-  PolyFillType     m_SubjFillType;
-  bool             m_ReverseOutput;
-  bool             m_UsingPolyTree; 
-  bool             m_StrictSimple;
-#ifdef use_xyz
-  ZFillCallback   m_ZFill; //custom callback 
-#endif
-  void SetWindingCount(TEdge& edge);
-  bool IsEvenOddFillType(const TEdge& edge) const;
-  bool IsEvenOddAltFillType(const TEdge& edge) const;
-  void InsertScanbeam(const cInt Y);
-  cInt PopScanbeam();
-  void InsertLocalMinimaIntoAEL(const cInt botY);
-  void InsertEdgeIntoAEL(TEdge *edge, TEdge* startEdge);
-  void AddEdgeToSEL(TEdge *edge);
-  void CopyAELToSEL();
-  void DeleteFromSEL(TEdge *e);
-  void DeleteFromAEL(TEdge *e);
-  void UpdateEdgeIntoAEL(TEdge *&e);
-  void SwapPositionsInSEL(TEdge *edge1, TEdge *edge2);
-  bool IsContributing(const TEdge& edge) const;
-  bool IsTopHorz(const cInt XPos);
-  void SwapPositionsInAEL(TEdge *edge1, TEdge *edge2);
-  void DoMaxima(TEdge *e);
-  void ProcessHorizontals(bool IsTopOfScanbeam);
-  void ProcessHorizontal(TEdge *horzEdge, bool isTopOfScanbeam);
-  void AddLocalMaxPoly(TEdge *e1, TEdge *e2, const IntPoint &pt);
-  OutPt* AddLocalMinPoly(TEdge *e1, TEdge *e2, const IntPoint &pt);
-  OutRec* GetOutRec(int idx);
-  void AppendPolygon(TEdge *e1, TEdge *e2);
-  void IntersectEdges(TEdge *e1, TEdge *e2, IntPoint &pt);
-  OutRec* CreateOutRec();
-  OutPt* AddOutPt(TEdge *e, const IntPoint &pt);
-  void DisposeAllOutRecs();
-  void DisposeOutRec(PolyOutList::size_type index);
-  bool ProcessIntersections(const cInt topY);
-  void BuildIntersectList(const cInt topY);
-  void ProcessIntersectList();
-  void ProcessEdgesAtTopOfScanbeam(const cInt topY);
-  void BuildResult(Paths& polys);
-  void BuildResult2(PolyTree& polytree);
-  void SetHoleState(TEdge *e, OutRec *outrec);
-  void DisposeIntersectNodes();
-  bool FixupIntersectionOrder();
-  void FixupOutPolygon(OutRec &outrec);
-  bool IsHole(TEdge *e);
-  bool FindOwnerFromSplitRecs(OutRec &outRec, OutRec *&currOrfl);
-  void FixHoleLinkage(OutRec &outrec);
-  void AddJoin(OutPt *op1, OutPt *op2, const IntPoint offPt);
-  void ClearJoins();
-  void ClearGhostJoins();
-  void AddGhostJoin(OutPt *op, const IntPoint offPt);
-  bool JoinPoints(Join *j, OutRec* outRec1, OutRec* outRec2);
-  void JoinCommonEdges();
-  void DoSimplePolygons();
-  void FixupFirstLefts1(OutRec* OldOutRec, OutRec* NewOutRec);
-  void FixupFirstLefts2(OutRec* OldOutRec, OutRec* NewOutRec);
-#ifdef use_xyz
-  void SetZ(IntPoint& pt, TEdge& e1, TEdge& e2);
-#endif
-};
-//------------------------------------------------------------------------------
-
-class ClipperOffset 
-{
-public:
-  ClipperOffset(double miterLimit = 2.0, double roundPrecision = 0.25);
-  ~ClipperOffset();
-  void AddPath(const Path& path, JoinType joinType, EndType endType);
-  void AddPaths(const Paths& paths, JoinType joinType, EndType endType);
-  void Execute(Paths& solution, double delta);
-  void Execute(PolyTree& solution, double delta);
-  void Clear();
-  double MiterLimit;
-  double ArcTolerance;
-private:
-  Paths m_destPolys;
-  Path m_srcPoly;
-  Path m_destPoly;
-  std::vector<DoublePoint> m_normals;
-  double m_delta, m_sinA, m_sin, m_cos;
-  double m_miterLim, m_StepsPerRad;
-  IntPoint m_lowest;
-  PolyNode m_polyNodes;
-
-  void FixOrientations();
-  void DoOffset(double delta);
-  void OffsetPoint(int j, int& k, JoinType jointype);
-  void DoSquare(int j, int k);
-  void DoMiter(int j, int k, double r);
-  void DoRound(int j, int k);
-};
-//------------------------------------------------------------------------------
-
-class clipperException : public std::exception
-{
-  public:
-    clipperException(const char* description): m_descr(description) {}
-    virtual ~clipperException() throw() {}
-    virtual const char* what() const throw() {return m_descr.c_str();}
-  private:
-    std::string m_descr;
-};
-//------------------------------------------------------------------------------
-
-} //ClipperLib namespace
-
-#endif //clipper_hpp
-
-

decode.cc

@@ -1,421 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sqlite3.h>
-#include <string>
-#include <zlib.h>
-#include <math.h>
-#include "vector_tile.pb.h"
-#include "tile.h"
-
-extern "C" {
-#include "projection.h"
-}
-
-// https://github.com/mapbox/mapnik-vector-tile/blob/master/src/vector_tile_compression.hpp
-inline bool is_compressed(std::string const &data) {
-	return data.size() > 2 && (((uint8_t) data[0] == 0x78 && (uint8_t) data[1] == 0x9C) || ((uint8_t) data[0] == 0x1F && (uint8_t) data[1] == 0x8B));
-}
-
-// https://github.com/mapbox/mapnik-vector-tile/blob/master/src/vector_tile_compression.hpp
-inline int decompress(std::string const &input, std::string &output) {
-	z_stream inflate_s;
-	inflate_s.zalloc = Z_NULL;
-	inflate_s.zfree = Z_NULL;
-	inflate_s.opaque = Z_NULL;
-	inflate_s.avail_in = 0;
-	inflate_s.next_in = Z_NULL;
-	if (inflateInit2(&inflate_s, 32 + 15) != Z_OK) {
-		fprintf(stderr, "error: %s\n", inflate_s.msg);
-	}
-	inflate_s.next_in = (Bytef *) input.data();
-	inflate_s.avail_in = input.size();
-	size_t length = 0;
-	do {
-		output.resize(length + 2 * input.size());
-		inflate_s.avail_out = 2 * input.size();
-		inflate_s.next_out = (Bytef *) (output.data() + length);
-		int ret = inflate(&inflate_s, Z_FINISH);
-		if (ret != Z_STREAM_END && ret != Z_OK && ret != Z_BUF_ERROR) {
-			fprintf(stderr, "error: %s\n", inflate_s.msg);
-			return 0;
-		}
-
-		length += (2 * input.size() - inflate_s.avail_out);
-	} while (inflate_s.avail_out == 0);
-	inflateEnd(&inflate_s);
-	output.resize(length);
-	return 1;
-}
-
-int dezig(unsigned n) {
-	return (n >> 1) ^ (-(n & 1));
-}
-
-void printq(const char *s) {
-	putchar('"');
-	for (; *s; s++) {
-		if (*s == '\\' || *s == '"') {
-			printf("\\%c", *s);
-		} else if (*s >= 0 && *s < ' ') {
-			printf("\\u%04x", *s);
-		} else {
-			putchar(*s);
-		}
-	}
-	putchar('"');
-}
-
-struct draw {
-	int op;
-	double lon;
-	double lat;
-
-	draw(int op, double lon, double lat) {
-		this->op = op;
-		this->lon = lon;
-		this->lat = lat;
-	}
-};
-
-void handle(std::string message, int z, unsigned x, unsigned y, int describe) {
-	GOOGLE_PROTOBUF_VERIFY_VERSION;
-	int within = 0;
-
-	// https://github.com/mapbox/mapnik-vector-tile/blob/master/examples/c%2B%2B/tileinfo.cpp
-	mapnik::vector::tile tile;
-
-	if (is_compressed(message)) {
-		std::string uncompressed;
-		decompress(message, uncompressed);
-		if (!tile.ParseFromString(uncompressed)) {
-			fprintf(stderr, "Couldn't decompress tile %d/%u/%u\n", z, x, y);
-			exit(EXIT_FAILURE);
-		}
-	} else if (!tile.ParseFromString(message)) {
-		fprintf(stderr, "Couldn't parse tile %d/%u/%u\n", z, x, y);
-		exit(EXIT_FAILURE);
-	}
-
-	printf("{ \"type\": \"FeatureCollection\"");
-
-	if (describe) {
-		printf(", \"properties\": { \"zoom\": %d, \"x\": %d, \"y\": %d }", z, x, y);
-	}
-
-	printf(", \"features\": [\n");
-
-	for (int l = 0; l < tile.layers_size(); l++) {
-		mapnik::vector::tile_layer layer = tile.layers(l);
-		int extent = layer.extent();
-
-		for (int f = 0; f < layer.features_size(); f++) {
-			mapnik::vector::tile_feature feat = layer.features(f);
-			int px = 0, py = 0;
-
-			if (within) {
-				printf(",\n");
-			}
-			within = 1;
-
-			printf("{ \"type\": \"Feature\"");
-			printf(", \"properties\": { ");
-
-			for (int t = 0; t + 1 < feat.tags_size(); t += 2) {
-				if (t != 0) {
-					printf(", ");
-				}
-
-				const char *key = layer.keys(feat.tags(t)).c_str();
-				mapnik::vector::tile_value const &val = layer.values(feat.tags(t + 1));
-
-				if (val.has_string_value()) {
-					printq(key);
-					printf(": ");
-					printq(val.string_value().c_str());
-				} else if (val.has_int_value()) {
-					printq(key);
-					printf(": %lld", (long long) val.int_value());
-				} else if (val.has_double_value()) {
-					printq(key);
-					printf(": %g", val.double_value());
-				} else if (val.has_float_value()) {
-					printq(key);
-					printf(": %g", val.float_value());
-				} else if (val.has_sint_value()) {
-					printq(key);
-					printf(": %lld", (long long) val.sint_value());
-				} else if (val.has_uint_value()) {
-					printq(key);
-					printf(": %lld", (long long) val.uint_value());
-				} else if (val.has_bool_value()) {
-					printq(key);
-					printf(": %s", val.bool_value() ? "true" : "false");
-				}
-			}
-
-			printf(" }, \"geometry\": { ");
-
-			std::vector<draw> ops;
-
-			for (int g = 0; g < feat.geometry_size(); g++) {
-				uint32_t geom = feat.geometry(g);
-				uint32_t op = geom & 7;
-				uint32_t count = geom >> 3;
-
-				if (op == VT_MOVETO || op == VT_LINETO) {
-					for (unsigned k = 0; k < count; k++) {
-						px += dezig(feat.geometry(g + 1));
-						py += dezig(feat.geometry(g + 2));
-						g += 2;
-
-						long long scale = 1LL << (32 - z);
-						long long wx = scale * x + (scale / extent) * (px + .5);
-						long long wy = scale * y + (scale / extent) * (py + .5);
-
-						double lat, lon;
-						tile2latlon(wx, wy, 32, &lat, &lon);
-
-						ops.push_back(draw(op, lon, lat));
-					}
-				} else {
-					ops.push_back(draw(op, 0, 0));
-				}
-			}
-
-			if (feat.type() == VT_POINT) {
-				if (ops.size() == 1) {
-					printf("\"type\": \"Point\", \"coordinates\": [ %f, %f ]", ops[0].lon, ops[0].lat);
-				} else {
-					printf("\"type\": \"MultiPoint\", \"coordinates\": [ ");
-					for (unsigned i = 0; i < ops.size(); i++) {
-						if (i != 0) {
-							printf(", ");
-						}
-						printf("[ %f, %f ]", ops[i].lon, ops[i].lat);
-					}
-					printf(" ]");
-				}
-			} else if (feat.type() == VT_LINE) {
-				int movetos = 0;
-				for (unsigned i = 0; i < ops.size(); i++) {
-					if (ops[i].op == VT_MOVETO) {
-						movetos++;
-					}
-				}
-
-				if (movetos < 2) {
-					printf("\"type\": \"LineString\", \"coordinates\": [ ");
-					for (unsigned i = 0; i < ops.size(); i++) {
-						if (i != 0) {
-							printf(", ");
-						}
-						printf("[ %f, %f ]", ops[i].lon, ops[i].lat);
-					}
-					printf(" ]");
-				} else {
-					printf("\"type\": \"MultiLineString\", \"coordinates\": [ [ ");
-					int state = 0;
-					for (unsigned i = 0; i < ops.size(); i++) {
-						if (ops[i].op == VT_MOVETO) {
-							if (state == 0) {
-								printf("[ %f, %f ]", ops[i].lon, ops[i].lat);
-								state = 1;
-							} else {
-								printf(" ], [ ");
-								printf("[ %f, %f ]", ops[i].lon, ops[i].lat);
-								state = 1;
-							}
-						} else {
-							printf(", [ %f, %f ]", ops[i].lon, ops[i].lat);
-						}
-					}
-					printf(" ] ]");
-				}
-			} else if (feat.type() == VT_POLYGON) {
-				std::vector<std::vector<draw> > rings;
-				std::vector<double> areas;
-
-				for (unsigned i = 0; i < ops.size(); i++) {
-					if (ops[i].op == VT_MOVETO) {
-						rings.push_back(std::vector<draw>());
-						areas.push_back(0);
-					}
-
-					int n = rings.size() - 1;
-					if (n >= 0) {
-						rings[n].push_back(ops[i]);
-					}
-				}
-
-				int outer = 0;
-
-				for (unsigned i = 0; i < rings.size(); i++) {
-					double area = 0;
-					for (unsigned k = 0; k < rings[i].size(); k++) {
-						if (rings[i][k].op != VT_CLOSEPATH) {
-							area += rings[i][k].lon * rings[i][(k + 1) % rings[i].size()].lat;
-							area -= rings[i][k].lat * rings[i][(k + 1) % rings[i].size()].lon;
-						}
-					}
-
-					areas[i] = area;
-					if (areas[i] <= 0) {
-						outer++;
-					}
-
-					// printf("area %f\n", area / .00000274 / .00000274);
-				}
-
-				if (outer > 1) {
-					printf("\"type\": \"MultiPolygon\", \"coordinates\": [ [ [ ");
-				} else {
-					printf("\"type\": \"Polygon\", \"coordinates\": [ [ ");
-				}
-
-				int state = 0;
-				for (unsigned i = 0; i < rings.size(); i++) {
-					if (areas[i] <= 0) {
-						if (state != 0) {
-							// new multipolygon
-							printf(" ] ], [ [ ");
-						}
-						state = 1;
-					}
-
-					if (state == 2) {
-						// new ring in the same polygon
-						printf(" ], [ ");
-					}
-
-					for (unsigned j = 0; j < rings[i].size(); j++) {
-						if (rings[i][j].op != VT_CLOSEPATH) {
-							if (j != 0) {
-								printf(", ");
-							}
-
-							printf("[ %f, %f ]", rings[i][j].lon, rings[i][j].lat);
-						}
-					}
-
-					state = 2;
-				}
-
-				if (outer > 1) {
-					printf(" ] ] ]");
-				} else {
-					printf(" ] ]");
-				}
-			}
-
-			printf(" } }\n");
-		}
-	}
-
-	printf("] }\n");
-}
-
-void decode(char *fname, int z, unsigned x, unsigned y) {
-	sqlite3 *db;
-	int oz = z;
-	unsigned ox = x, oy = y;
-
-	if (sqlite3_open(fname, &db) != SQLITE_OK) {
-		fprintf(stderr, "%s: %s\n", fname, sqlite3_errmsg(db));
-		exit(EXIT_FAILURE);
-	}
-
-	if (z < 0) {
-		const char *sql = "SELECT tile_data, zoom_level, tile_column, tile_row from tiles order by zoom_level, tile_column, tile_row;";
-		sqlite3_stmt *stmt;
-		if (sqlite3_prepare_v2(db, sql, -1, &stmt, NULL) != SQLITE_OK) {
-			fprintf(stderr, "%s: select failed: %s\n", fname, sqlite3_errmsg(db));
-			exit(EXIT_FAILURE);
-		}
-
-		printf("{ \"type\": \"FeatureCollection\", \"features\": [\n");
-
-		int within = 0;
-		while (sqlite3_step(stmt) == SQLITE_ROW) {
-			if (within) {
-				printf(",\n");
-			}
-			within = 1;
-
-			int len = sqlite3_column_bytes(stmt, 0);
-			int z = sqlite3_column_int(stmt, 1);
-			int x = sqlite3_column_int(stmt, 2);
-			int y = sqlite3_column_int(stmt, 3);
-			y = (1LL << z) - 1 - y;
-			const char *s = (const char *) sqlite3_column_blob(stmt, 0);
-
-			handle(std::string(s, len), z, x, y, 1);
-		}
-
-		printf("] }\n");
-
-		sqlite3_finalize(stmt);
-	} else {
-		int handled = 0;
-		while (z >= 0 && !handled) {
-			const char *sql = "SELECT tile_data from tiles where zoom_level = ? and tile_column = ? and tile_row = ?;";
-			sqlite3_stmt *stmt;
-			if (sqlite3_prepare_v2(db, sql, -1, &stmt, NULL) != SQLITE_OK) {
-				fprintf(stderr, "%s: select failed: %s\n", fname, sqlite3_errmsg(db));
-				exit(EXIT_FAILURE);
-			}
-
-			sqlite3_bind_int(stmt, 1, z);
-			sqlite3_bind_int(stmt, 2, x);
-			sqlite3_bind_int(stmt, 3, (1LL << z) - 1 - y);
-
-			while (sqlite3_step(stmt) == SQLITE_ROW) {
-				int len = sqlite3_column_bytes(stmt, 0);
-				const char *s = (const char *) sqlite3_column_blob(stmt, 0);
-
-				if (z != oz) {
-					fprintf(stderr, "%s: Warning: using tile %d/%u/%u instead of %d/%u/%u\n", fname, z, x, y, oz, ox, oy);
-				}
-
-				handle(std::string(s, len), z, x, y, 0);
-				handled = 1;
-			}
-
-			sqlite3_finalize(stmt);
-
-			z--;
-			x /= 2;
-			y /= 2;
-		}
-	}
-
-	if (sqlite3_close(db) != SQLITE_OK) {
-		fprintf(stderr, "%s: could not close database: %s\n", fname, sqlite3_errmsg(db));
-		exit(EXIT_FAILURE);
-	}
-}
-
-void usage(char **argv) {
-	fprintf(stderr, "Usage: %s file.mbtiles zoom x y\n", argv[0]);
-	exit(EXIT_FAILURE);
-}
-
-int main(int argc, char **argv) {
-	extern int optind;
-	// extern char *optarg;
-	int i;
-
-	while ((i = getopt(argc, argv, "")) != -1) {
-		usage(argv);
-	}
-
-	if (argc == optind + 4) {
-		decode(argv[optind], atoi(argv[optind + 1]), atoi(argv[optind + 2]), atoi(argv[optind + 3]));
-	} else if (argc == optind + 1) {
-		decode(argv[optind], -1, -1, -1);
-	} else {
-		usage(argv);
-	}
-
-	return 0;
-}

decode.cpp

@@ -0,0 +1,398 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sqlite3.h>
+#include <getopt.h>
+#include <string>
+#include <vector>
+#include <map>
+#include <set>
+#include <zlib.h>
+#include <math.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <protozero/pbf_reader.hpp>
+#include "mvt.hpp"
+#include "projection.hpp"
+#include "geometry.hpp"
+#include "write_json.hpp"
+
+int minzoom = 0;
+int maxzoom = 32;
+bool force = false;
+
+void do_stats(mvt_tile &tile, size_t size, bool compressed, int z, unsigned x, unsigned y) {
+	printf("{ \"zoom\": %d, \"x\": %u, \"y\": %u, \"bytes\": %zu, \"compressed\": %s", z, x, y, size, compressed ? "true" : "false");
+
+	printf(", \"layers\": { ");
+	for (size_t i = 0; i < tile.layers.size(); i++) {
+		if (i != 0) {
+			printf(", ");
+		}
+		fprintq(stdout, tile.layers[i].name.c_str());
+
+		int points = 0, lines = 0, polygons = 0;
+		for (size_t j = 0; j < tile.layers[i].features.size(); j++) {
+			if (tile.layers[i].features[j].type == mvt_point) {
+				points++;
+			} else if (tile.layers[i].features[j].type == mvt_linestring) {
+				lines++;
+			} else if (tile.layers[i].features[j].type == mvt_polygon) {
+				polygons++;
+			}
+		}
+
+		printf(": { \"points\": %d, \"lines\": %d, \"polygons\": %d, \"extent\": %lld }", points, lines, polygons, tile.layers[i].extent);
+	}
+
+	printf(" } }\n");
+}
+
+void handle(std::string message, int z, unsigned x, unsigned y, int describe, std::set<std::string> const &to_decode, bool pipeline, bool stats) {
+	mvt_tile tile;
+	bool was_compressed;
+
+	try {
+		if (!tile.decode(message, was_compressed)) {
+			fprintf(stderr, "Couldn't parse tile %d/%u/%u\n", z, x, y);
+			exit(EXIT_FAILURE);
+		}
+	} catch (protozero::unknown_pbf_wire_type_exception e) {
+		fprintf(stderr, "PBF decoding error in tile %d/%u/%u\n", z, x, y);
+		exit(EXIT_FAILURE);
+	}
+
+	if (stats) {
+		do_stats(tile, message.size(), was_compressed, z, x, y);
+		return;
+	}
+
+	if (!pipeline) {
+		printf("{ \"type\": \"FeatureCollection\"");
+
+		if (describe) {
+			printf(", \"properties\": { \"zoom\": %d, \"x\": %d, \"y\": %d", z, x, y);
+			if (!was_compressed) {
+				printf(", \"compressed\": false");
+			}
+			printf(" }");
+
+			if (projection != projections) {
+				printf(", \"crs\": { \"type\": \"name\", \"properties\": { \"name\": ");
+				fprintq(stdout, projection->alias);
+				printf(" } }");
+			}
+		}
+
+		printf(", \"features\": [\n");
+	}
+
+	bool first_layer = true;
+	for (size_t l = 0; l < tile.layers.size(); l++) {
+		mvt_layer &layer = tile.layers[l];
+
+		if (layer.extent <= 0) {
+			fprintf(stderr, "Impossible layer extent %lld in mbtiles\n", layer.extent);
+			exit(EXIT_FAILURE);
+		}
+
+		if (to_decode.size() != 0 && !to_decode.count(layer.name)) {
+			continue;
+		}
+
+		if (!pipeline) {
+			if (describe) {
+				if (!first_layer) {
+					printf(",\n");
+				}
+
+				printf("{ \"type\": \"FeatureCollection\"");
+				printf(", \"properties\": { \"layer\": ");
+				fprintq(stdout, layer.name.c_str());
+				printf(", \"version\": %d, \"extent\": %lld", layer.version, layer.extent);
+				printf(" }");
+				printf(", \"features\": [\n");
+
+				first_layer = false;
+			}
+		}
+
+		// X and Y are unsigned, so no need to check <0
+		if (x > (1 << z) || y > (1 << z)) {
+			fprintf(stderr, "Impossible tile %d/%u/%u\n", z, x, y);
+			exit(EXIT_FAILURE);
+		}
+
+		layer_to_geojson(stdout, layer, z, x, y, !pipeline, pipeline, pipeline, 0, 0, 0, !force);
+
+		if (!pipeline) {
+			if (describe) {
+				printf("] }\n");
+			}
+		}
+	}
+
+	if (!pipeline) {
+		printf("] }\n");
+	}
+}
+
+void decode(char *fname, int z, unsigned x, unsigned y, std::set<std::string> const &to_decode, bool pipeline, bool stats) {
+	sqlite3 *db;
+	int oz = z;
+	unsigned ox = x, oy = y;
+
+	int fd = open(fname, O_RDONLY | O_CLOEXEC);
+	if (fd >= 0) {
+		struct stat st;
+		if (fstat(fd, &st) == 0) {
+			if (st.st_size < 50 * 1024 * 1024) {
+				char *map = (char *) mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+				if (map != NULL && map != MAP_FAILED) {
+					if (strcmp(map, "SQLite format 3") != 0) {
+						if (z >= 0) {
+							std::string s = std::string(map, st.st_size);
+							handle(s, z, x, y, 1, to_decode, pipeline, stats);
+							munmap(map, st.st_size);
+							return;
+						} else {
+							fprintf(stderr, "Must specify zoom/x/y to decode a single pbf file\n");
+							exit(EXIT_FAILURE);
+						}
+					}
+				}
+				munmap(map, st.st_size);
+			}
+		} else {
+			perror("fstat");
+		}
+		if (close(fd) != 0) {
+			perror("close");
+			exit(EXIT_FAILURE);
+		}
+	} else {
+		perror(fname);
+	}
+
+	if (sqlite3_open(fname, &db) != SQLITE_OK) {
+		fprintf(stderr, "%s: %s\n", fname, sqlite3_errmsg(db));
+		exit(EXIT_FAILURE);
+	}
+
+	if (z < 0) {
+		int within = 0;
+
+		if (!pipeline && !stats) {
+			printf("{ \"type\": \"FeatureCollection\", \"properties\": {\n");
+
+			const char *sql2 = "SELECT name, value from metadata order by name;";
+			sqlite3_stmt *stmt2;
+			if (sqlite3_prepare_v2(db, sql2, -1, &stmt2, NULL) != SQLITE_OK) {
+				fprintf(stderr, "%s: select failed: %s\n", fname, sqlite3_errmsg(db));
+				exit(EXIT_FAILURE);
+			}
+
+			while (sqlite3_step(stmt2) == SQLITE_ROW) {
+				if (within) {
+					printf(",\n");
+				}
+				within = 1;
+
+				const unsigned char *name = sqlite3_column_text(stmt2, 0);
+				const unsigned char *value = sqlite3_column_text(stmt2, 1);
+
+				if (name == NULL || value == NULL) {
+					fprintf(stderr, "Corrupt mbtiles file: null metadata\n");
+					exit(EXIT_FAILURE);
+				}
+
+				fprintq(stdout, (char *) name);
+				printf(": ");
+				fprintq(stdout, (char *) value);
+			}
+
+			sqlite3_finalize(stmt2);
+		}
+
+		if (stats) {
+			printf("[\n");
+		}
+
+		const char *sql = "SELECT tile_data, zoom_level, tile_column, tile_row from tiles where zoom_level between ? and ? order by zoom_level, tile_column, tile_row;";
+		sqlite3_stmt *stmt;
+		if (sqlite3_prepare_v2(db, sql, -1, &stmt, NULL) != SQLITE_OK) {
+			fprintf(stderr, "%s: select failed: %s\n", fname, sqlite3_errmsg(db));
+			exit(EXIT_FAILURE);
+		}
+
+		sqlite3_bind_int(stmt, 1, minzoom);
+		sqlite3_bind_int(stmt, 2, maxzoom);
+
+		if (!pipeline && !stats) {
+			printf("\n}, \"features\": [\n");
+		}
+
+		within = 0;
+		while (sqlite3_step(stmt) == SQLITE_ROW) {
+			if (!pipeline && !stats) {
+				if (within) {
+					printf(",\n");
+				}
+				within = 1;
+			}
+			if (stats) {
+				if (within) {
+					printf(",\n");
+				}
+				within = 1;
+			}
+
+			int len = sqlite3_column_bytes(stmt, 0);
+			int tz = sqlite3_column_int(stmt, 1);
+			int tx = sqlite3_column_int(stmt, 2);
+			int ty = sqlite3_column_int(stmt, 3);
+
+			if (tz < 0 || tz >= 32) {
+				fprintf(stderr, "Impossible zoom level %d in mbtiles\n", tz);
+				exit(EXIT_FAILURE);
+			}
+
+			ty = (1LL << tz) - 1 - ty;
+			const char *s = (const char *) sqlite3_column_blob(stmt, 0);
+
+			handle(std::string(s, len), tz, tx, ty, 1, to_decode, pipeline, stats);
+		}
+
+		if (!pipeline && !stats) {
+			printf("] }\n");
+		}
+		if (stats) {
+			printf("]\n");
+		}
+
+		sqlite3_finalize(stmt);
+	} else {
+		int handled = 0;
+		while (z >= 0 && !handled) {
+			const char *sql = "SELECT tile_data from tiles where zoom_level = ? and tile_column = ? and tile_row = ?;";
+			sqlite3_stmt *stmt;
+			if (sqlite3_prepare_v2(db, sql, -1, &stmt, NULL) != SQLITE_OK) {
+				fprintf(stderr, "%s: select failed: %s\n", fname, sqlite3_errmsg(db));
+				exit(EXIT_FAILURE);
+			}
+
+			sqlite3_bind_int(stmt, 1, z);
+			sqlite3_bind_int(stmt, 2, x);
+			sqlite3_bind_int(stmt, 3, (1LL << z) - 1 - y);
+
+			while (sqlite3_step(stmt) == SQLITE_ROW) {
+				int len = sqlite3_column_bytes(stmt, 0);
+				const char *s = (const char *) sqlite3_column_blob(stmt, 0);
+
+				if (z != oz) {
+					fprintf(stderr, "%s: Warning: using tile %d/%u/%u instead of %d/%u/%u\n", fname, z, x, y, oz, ox, oy);
+				}
+
+				handle(std::string(s, len), z, x, y, 0, to_decode, pipeline, stats);
+				handled = 1;
+			}
+
+			sqlite3_finalize(stmt);
+
+			z--;
+			x /= 2;
+			y /= 2;
+		}
+	}
+
+	if (sqlite3_close(db) != SQLITE_OK) {
+		fprintf(stderr, "%s: could not close database: %s\n", fname, sqlite3_errmsg(db));
+		exit(EXIT_FAILURE);
+	}
+}
+
+void usage(char **argv) {
+	fprintf(stderr, "Usage: %s [-s projection] [-Z minzoom] [-z maxzoom] [-l layer ...] file.mbtiles [zoom x y]\n", argv[0]);
+	exit(EXIT_FAILURE);
+}
+
+int main(int argc, char **argv) {
+	extern int optind;
+	extern char *optarg;
+	int i;
+	std::set<std::string> to_decode;
+	bool pipeline = false;
+	bool stats = false;
+
+	struct option long_options[] = {
+		{"projection", required_argument, 0, 's'},
+		{"maximum-zoom", required_argument, 0, 'z'},
+		{"minimum-zoom", required_argument, 0, 'Z'},
+		{"layer", required_argument, 0, 'l'},
+		{"tag-layer-and-zoom", no_argument, 0, 'c'},
+		{"stats", no_argument, 0, 'S'},
+		{"force", no_argument, 0, 'f'},
+		{0, 0, 0, 0},
+	};
+
+	std::string getopt_str;
+	for (size_t lo = 0; long_options[lo].name != NULL; lo++) {
+		if (long_options[lo].val > ' ') {
+			getopt_str.push_back(long_options[lo].val);
+
+			if (long_options[lo].has_arg == required_argument) {
+				getopt_str.push_back(':');
+			}
+		}
+	}
+
+	while ((i = getopt_long(argc, argv, getopt_str.c_str(), long_options, NULL)) != -1) {
+		switch (i) {
+		case 0:
+			break;
+
+		case 's':
+			set_projection_or_exit(optarg);
+			break;
+
+		case 'z':
+			maxzoom = atoi(optarg);
+			break;
+
+		case 'Z':
+			minzoom = atoi(optarg);
+			break;
+
+		case 'l':
+			to_decode.insert(optarg);
+			break;
+
+		case 'c':
+			pipeline = true;
+			break;
+
+		case 'S':
+			stats = true;
+			break;
+
+		case 'f':
+			force = true;
+			break;
+
+		default:
+			usage(argv);
+		}
+	}
+
+	if (argc == optind + 4) {
+		decode(argv[optind], atoi(argv[optind + 1]), atoi(argv[optind + 2]), atoi(argv[optind + 3]), to_decode, pipeline, stats);
+	} else if (argc == optind + 1) {
+		decode(argv[optind], -1, -1, -1, to_decode, pipeline, stats);
+	} else {
+		usage(argv);
+	}
+
+	return 0;
+}

dirtiles.cpp

@@ -0,0 +1,126 @@
+#include <iostream>
+#include <fstream>
+#include <sstream>
+#include <string>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include "dirtiles.hpp"
+
+std::string dir_read_tile(std::string pbfPath) {
+	std::ifstream pbfFile(pbfPath, std::ios::in | std::ios::binary);
+	std::ostringstream contents;
+	contents << pbfFile.rdbuf();
+	pbfFile.close();
+
+	return (contents.str());
+}
+
+void dir_write_tile(const char *outdir, int z, int tx, int ty, std::string const &pbf) {
+	mkdir(outdir, S_IRWXU | S_IRWXG | S_IRWXO);
+	std::string curdir(outdir);
+	std::string slash("/");
+	std::string newdir = curdir + slash + std::to_string(z);
+	mkdir(newdir.c_str(), S_IRWXU | S_IRWXG | S_IRWXO);
+	newdir = newdir + "/" + std::to_string(tx);
+	mkdir(newdir.c_str(), S_IRWXU | S_IRWXG | S_IRWXO);
+	newdir = newdir + "/" + std::to_string(ty) + ".pbf";
+
+	struct stat st;
+	if (stat(newdir.c_str(), &st) == 0) {
+		fprintf(stderr, "Can't write tile to already existing %s\n", newdir.c_str());
+		exit(EXIT_FAILURE);
+	}
+
+	std::ofstream pbfFile(newdir, std::ios::out | std::ios::binary);
+	pbfFile.write(pbf.data(), pbf.size());
+	pbfFile.close();
+}
+
+bool numeric(const char *s) {
+	if (*s == '\0') {
+		return false;
+	}
+	for (; *s != 0; s++) {
+		if (*s < '0' || *s > '9') {
+			return false;
+		}
+	}
+	return true;
+}
+
+bool pbfname(const char *s) {
+	while (*s >= '0' && *s <= '9') {
+		s++;
+	}
+
+	return strcmp(s, ".pbf") == 0;
+}
+
+void check_dir(const char *dir, bool rm) {
+	struct stat st;
+
+	std::string meta = std::string(dir) + "/" + "metadata.json";
+	if (rm) {
+		unlink(meta.c_str());  // error OK since it may not exist;
+	} else {
+		if (stat(meta.c_str(), &st) == 0) {
+			fprintf(stderr, "%s: file exists\n", meta.c_str());
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	DIR *d1 = opendir(dir);
+	if (d1 != NULL) {
+		struct dirent *dp;
+		while ((dp = readdir(d1)) != NULL) {
+			if (numeric(dp->d_name)) {
+				std::string z = std::string(dir) + "/" + dp->d_name;
+
+				DIR *d2 = opendir(z.c_str());
+				if (d2 == NULL) {
+					perror(z.c_str());
+					exit(EXIT_FAILURE);
+				}
+
+				struct dirent *dp2;
+				while ((dp2 = readdir(d2)) != NULL) {
+					if (numeric(dp2->d_name)) {
+						std::string x = z + "/" + dp2->d_name;
+
+						DIR *d3 = opendir(x.c_str());
+						if (d3 == NULL) {
+							perror(x.c_str());
+							exit(EXIT_FAILURE);
+						}
+
+						struct dirent *dp3;
+						while ((dp3 = readdir(d3)) != NULL) {
+							if (pbfname(dp3->d_name)) {
+								std::string y = x + "/" + dp3->d_name;
+
+								if (rm) {
+									if (unlink(y.c_str()) != 0) {
+										perror(y.c_str());
+										exit(EXIT_FAILURE);
+									}
+								} else {
+									fprintf(stderr, "%s: file exists\n", y.c_str());
+									exit(EXIT_FAILURE);
+								}
+							}
+						}
+
+						closedir(d3);
+					}
+				}
+
+				closedir(d2);
+			}
+		}
+
+		closedir(d1);
+	}
+}

dirtiles.hpp

@@ -0,0 +1,12 @@
+#include <string>
+
+#ifndef DIRTILES_HPP
+#define DIRTILES_HPP
+
+std::string dir_read_tile(std::string pbfPath);
+
+void dir_write_tile(const char *outdir, int z, int tx, int ty, std::string const &pbf);
+
+void check_dir(const char *d, bool rm);
+
+#endif

enumerate.cpp

@@ -11,7 +11,7 @@ void enumerate(char *fname) {
 		exit(EXIT_FAILURE);
 	}
 
-	char *sql = "SELECT zoom_level, tile_column, tile_row from tiles;";
+	const char *sql = "SELECT zoom_level, tile_column, tile_row from tiles order by zoom_level, tile_column, tile_row;";
 
 	sqlite3_stmt *stmt;
 	if (sqlite3_prepare_v2(db, sql, -1, &stmt, NULL) != SQLITE_OK) {
@@ -24,6 +24,11 @@ void enumerate(char *fname) {
 		long long x = sqlite3_column_int(stmt, 1);
 		long long y = sqlite3_column_int(stmt, 2);
 
+		if (zoom < 0 || zoom > 31) {
+			fprintf(stderr, "Corrupt mbtiles file: impossible zoom level %lld\n", zoom);
+			exit(EXIT_FAILURE);
+		}
+
 		y = (1LL << zoom) - 1 - y;
 		printf("%s %lld %lld %lld\n", fname, zoom, x, y);
 	}

evaluator.cpp

@@ -0,0 +1,328 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <map>
+#include "mvt.hpp"
+#include "evaluator.hpp"
+
+int compare(mvt_value one, json_object *two, bool &fail) {
+	if (one.type == mvt_string) {
+		if (two->type != JSON_STRING) {
+			fail = true;
+			return false;  // string vs non-string
+		}
+
+		return strcmp(one.string_value.c_str(), two->string);
+	}
+
+	if (one.type == mvt_double || one.type == mvt_float || one.type == mvt_int || one.type == mvt_uint || one.type == mvt_sint) {
+		if (two->type != JSON_NUMBER) {
+			fail = true;
+			return false;  // number vs non-number
+		}
+
+		double v;
+		if (one.type == mvt_double) {
+			v = one.numeric_value.double_value;
+		} else if (one.type == mvt_float) {
+			v = one.numeric_value.float_value;
+		} else if (one.type == mvt_int) {
+			v = one.numeric_value.int_value;
+		} else if (one.type == mvt_uint) {
+			v = one.numeric_value.uint_value;
+		} else if (one.type == mvt_sint) {
+			v = one.numeric_value.sint_value;
+		} else {
+			fprintf(stderr, "Internal error: bad mvt type %d\n", one.type);
+			exit(EXIT_FAILURE);
+		}
+
+		if (v < two->number) {
+			return -1;
+		} else if (v > two->number) {
+			return 1;
+		} else {
+			return 0;
+		}
+	}
+
+	if (one.type == mvt_bool) {
+		if (two->type != JSON_TRUE && two->type != JSON_FALSE) {
+			fail = true;
+			return false;  // bool vs non-bool
+		}
+
+		bool b = two->type != JSON_FALSE;
+		return one.numeric_value.bool_value > b;
+	}
+
+	if (one.type == mvt_null) {
+		if (two->type != JSON_NULL) {
+			fail = true;
+			return false;  // null vs non-null
+		}
+
+		return 0;  // null equals null
+	}
+
+	fprintf(stderr, "Internal error: bad mvt type %d\n", one.type);
+	exit(EXIT_FAILURE);
+}
+
+bool eval(std::map<std::string, mvt_value> const &feature, json_object *f) {
+	if (f == NULL || f->type != JSON_ARRAY) {
+		fprintf(stderr, "Filter is not an array: %s\n", json_stringify(f));
+		exit(EXIT_FAILURE);
+	}
+
+	if (f->length < 1) {
+		fprintf(stderr, "Array too small in filter: %s\n", json_stringify(f));
+		exit(EXIT_FAILURE);
+	}
+
+	if (f->array[0]->type != JSON_STRING) {
+		fprintf(stderr, "Filter operation is not a string: %s\n", json_stringify(f));
+		exit(EXIT_FAILURE);
+	}
+
+	if (strcmp(f->array[0]->string, "has") == 0 ||
+	    strcmp(f->array[0]->string, "!has") == 0) {
+		if (f->length != 2) {
+			fprintf(stderr, "Wrong number of array elements in filter: %s\n", json_stringify(f));
+			exit(EXIT_FAILURE);
+		}
+
+		if (strcmp(f->array[0]->string, "has") == 0) {
+			if (f->array[1]->type != JSON_STRING) {
+				fprintf(stderr, "\"has\" key is not a string: %s\n", json_stringify(f));
+				exit(EXIT_FAILURE);
+			}
+			return feature.count(std::string(f->array[1]->string)) != 0;
+		}
+
+		if (strcmp(f->array[0]->string, "!has") == 0) {
+			if (f->array[1]->type != JSON_STRING) {
+				fprintf(stderr, "\"!has\" key is not a string: %s\n", json_stringify(f));
+				exit(EXIT_FAILURE);
+			}
+			return feature.count(std::string(f->array[1]->string)) == 0;
+		}
+	}
+
+	if (strcmp(f->array[0]->string, "==") == 0 ||
+	    strcmp(f->array[0]->string, "!=") == 0 ||
+	    strcmp(f->array[0]->string, ">") == 0 ||
+	    strcmp(f->array[0]->string, ">=") == 0 ||
+	    strcmp(f->array[0]->string, "<") == 0 ||
+	    strcmp(f->array[0]->string, "<=") == 0) {
+		if (f->length != 3) {
+			fprintf(stderr, "Wrong number of array elements in filter: %s\n", json_stringify(f));
+			exit(EXIT_FAILURE);
+		}
+		if (f->array[1]->type != JSON_STRING) {
+			fprintf(stderr, "\"!has\" key is not a string: %s\n", json_stringify(f));
+			exit(EXIT_FAILURE);
+		}
+
+		auto ff = feature.find(std::string(f->array[1]->string));
+		if (ff == feature.end()) {
+			static bool warned = false;
+			if (!warned) {
+				const char *s = json_stringify(f);
+				fprintf(stderr, "Warning: attribute not found for comparison: %s\n", s);
+				free((void *) s);
+				warned = true;
+			}
+			if (strcmp(f->array[0]->string, "!=") == 0) {
+				return true;  //  attributes that aren't found are not equal
+			}
+			return false;  // not found: comparison is false
+		}
+
+		bool fail = false;
+		int cmp = compare(ff->second, f->array[2], fail);
+
+		if (fail) {
+			static bool warned = false;
+			if (!warned) {
+				const char *s = json_stringify(f);
+				fprintf(stderr, "Warning: mismatched type in comparison: %s\n", s);
+				free((void *) s);
+				warned = true;
+			}
+			if (strcmp(f->array[0]->string, "!=") == 0) {
+				return true;  // mismatched types are not equal
+			}
+			return false;
+		}
+
+		if (strcmp(f->array[0]->string, "==") == 0) {
+			return cmp == 0;
+		}
+		if (strcmp(f->array[0]->string, "!=") == 0) {
+			return cmp != 0;
+		}
+		if (strcmp(f->array[0]->string, ">") == 0) {
+			return cmp > 0;
+		}
+		if (strcmp(f->array[0]->string, ">=") == 0) {
+			return cmp >= 0;
+		}
+		if (strcmp(f->array[0]->string, "<") == 0) {
+			return cmp < 0;
+		}
+		if (strcmp(f->array[0]->string, "<=") == 0) {
+			return cmp <= 0;
+		}
+
+		fprintf(stderr, "Internal error: can't happen: %s\n", json_stringify(f));
+		exit(EXIT_FAILURE);
+	}
+
+	if (strcmp(f->array[0]->string, "all") == 0 ||
+	    strcmp(f->array[0]->string, "any") == 0 ||
+	    strcmp(f->array[0]->string, "none") == 0) {
+		bool v;
+
+		if (strcmp(f->array[0]->string, "all") == 0) {
+			v = true;
+		} else {
+			v = false;
+		}
+
+		for (size_t i = 1; i < f->length; i++) {
+			bool out = eval(feature, f->array[i]);
+
+			if (strcmp(f->array[0]->string, "all") == 0) {
+				v = v && out;
+				if (!v) {
+					break;
+				}
+			} else {
+				v = v || out;
+				if (v) {
+					break;
+				}
+			}
+		}
+
+		if (strcmp(f->array[0]->string, "none") == 0) {
+			return !v;
+		} else {
+			return v;
+		}
+	}
+
+	if (strcmp(f->array[0]->string, "in") == 0 ||
+	    strcmp(f->array[0]->string, "!in") == 0) {
+		if (f->length < 2) {
+			fprintf(stderr, "Array too small in filter: %s\n", json_stringify(f));
+			exit(EXIT_FAILURE);
+		}
+
+		if (f->array[1]->type != JSON_STRING) {
+			fprintf(stderr, "\"!has\" key is not a string: %s\n", json_stringify(f));
+			exit(EXIT_FAILURE);
+		}
+
+		auto ff = feature.find(std::string(f->array[1]->string));
+		if (ff == feature.end()) {
+			static bool warned = false;
+			if (!warned) {
+				const char *s = json_stringify(f);
+				fprintf(stderr, "Warning: attribute not found for comparison: %s\n", s);
+				free((void *) s);
+				warned = true;
+			}
+			if (strcmp(f->array[0]->string, "!in") == 0) {
+				return true;  // attributes that aren't found are not in
+			}
+			return false;  // not found: comparison is false
+		}
+
+		bool found = false;
+		for (size_t i = 2; i < f->length; i++) {
+			bool fail = false;
+			int cmp = compare(ff->second, f->array[i], fail);
+
+			if (fail) {
+				static bool warned = false;
+				if (!warned) {
+					const char *s = json_stringify(f);
+					fprintf(stderr, "Warning: mismatched type in comparison: %s\n", s);
+					free((void *) s);
+					warned = true;
+				}
+				cmp = 1;
+			}
+
+			if (cmp == 0) {
+				found = true;
+				break;
+			}
+		}
+
+		if (strcmp(f->array[0]->string, "in") == 0) {
+			return found;
+		} else {
+			return !found;
+		}
+	}
+
+	fprintf(stderr, "Unknown filter %s\n", json_stringify(f));
+	exit(EXIT_FAILURE);
+}
+
+bool evaluate(std::map<std::string, mvt_value> const &feature, std::string const &layer, json_object *filter) {
+	if (filter == NULL || filter->type != JSON_HASH) {
+		fprintf(stderr, "Error: filter is not a hash: %s\n", json_stringify(filter));
+		exit(EXIT_FAILURE);
+	}
+
+	bool ok = true;
+	json_object *f;
+
+	f = json_hash_get(filter, layer.c_str());
+	if (ok && f != NULL) {
+		ok = eval(feature, f);
+	}
+
+	f = json_hash_get(filter, "*");
+	if (ok && f != NULL) {
+		ok = eval(feature, f);
+	}
+
+	return ok;
+}
+
+json_object *read_filter(const char *fname) {
+	FILE *fp = fopen(fname, "r");
+	if (fp == NULL) {
+		perror(fname);
+		exit(EXIT_FAILURE);
+	}
+
+	json_pull *jp = json_begin_file(fp);
+	json_object *filter = json_read_tree(jp);
+	if (filter == NULL) {
+		fprintf(stderr, "%s: %s\n", fname, jp->error);
+		exit(EXIT_FAILURE);
+	}
+	json_disconnect(filter);
+	json_end(jp);
+	fclose(fp);
+	return filter;
+}
+
+json_object *parse_filter(const char *s) {
+	json_pull *jp = json_begin_string(s);
+	json_object *filter = json_read_tree(jp);
+	if (filter == NULL) {
+		fprintf(stderr, "Could not parse filter %s\n", s);
+		fprintf(stderr, "%s\n", jp->error);
+		exit(EXIT_FAILURE);
+	}
+	json_disconnect(filter);
+	json_end(jp);
+	return filter;
+}

evaluator.hpp

@@ -0,0 +1,13 @@
+#ifndef EVALUATOR_HPP
+#define EVALUATOR HPP
+
+#include <map>
+#include <string>
+#include "jsonpull/jsonpull.h"
+#include "mvt.hpp"
+
+bool evaluate(std::map<std::string, mvt_value> const &feature, std::string const &layer, json_object *filter);
+json_object *parse_filter(const char *s);
+json_object *read_filter(const char *fname);
+
+#endif

filters/limit-tiles-to-bbox

@@ -0,0 +1,27 @@
+#!/usr/bin/perl
+
+use Math::Trig;
+use strict;
+
+# http://wiki.openstreetmap.org/wiki/Slippy_map_tilenames
+sub getTileNumber {
+	my ($lat, $lon, $zoom) = @_;
+	my $xtile = int(($lon + 180) / 360 * 2 ** $zoom);
+	my $ytile = int((1 - log(tan(deg2rad($lat)) + sec(deg2rad($lat))) / pi) / 2 * 2 ** $zoom);
+	return ($xtile, $ytile);
+}
+
+my ($minlon, $minlat, $maxlon, $maxlat, $z, $x, $y) = @ARGV;
+
+my ($x1, $y1) = getTileNumber($maxlat, $minlon, $z);
+my ($x2, $y2) = getTileNumber($minlat, $maxlon, $z);
+
+if ($x >= $x1 && $x <= $x2 && $y >= $y1 && $y <= $y2) {
+	while (<STDIN>) {
+		print;
+	}
+} else {
+	while (<STDIN>) {
+
+	}
+}

geobuf.cpp

@@ -0,0 +1,572 @@
+#include <stdio.h>
+#include <string>
+#include <limits.h>
+#include <pthread.h>
+#include "mvt.hpp"
+#include "serial.hpp"
+#include "geobuf.hpp"
+#include "geojson.hpp"
+#include "projection.hpp"
+#include "main.hpp"
+#include "protozero/varint.hpp"
+#include "protozero/pbf_reader.hpp"
+#include "protozero/pbf_writer.hpp"
+#include "milo/dtoa_milo.h"
+#include "jsonpull/jsonpull.h"
+
+#define POINT 0
+#define MULTIPOINT 1
+#define LINESTRING 2
+#define MULTILINESTRING 3
+#define POLYGON 4
+#define MULTIPOLYGON 5
+
+struct queued_feature {
+	protozero::pbf_reader pbf;
+	size_t dim;
+	double e;
+	std::vector<std::string> *keys;
+	struct serialization_state *sst;
+	int layer;
+	std::string layername;
+};
+
+static std::vector<queued_feature> feature_queue;
+
+void ensureDim(size_t dim) {
+	if (dim < 2) {
+		fprintf(stderr, "Geometry has fewer than 2 dimensions: %zu\n", dim);
+		exit(EXIT_FAILURE);
+	}
+}
+
+serial_val readValue(protozero::pbf_reader &pbf, std::vector<std::string> &keys) {
+	serial_val sv;
+	sv.type = mvt_null;
+	sv.s = "null";
+
+	while (pbf.next()) {
+		switch (pbf.tag()) {
+		case 1:
+			sv.type = mvt_string;
+			sv.s = pbf.get_string();
+			break;
+
+		case 2:
+			sv.type = mvt_double;
+			sv.s = milo::dtoa_milo(pbf.get_double());
+			break;
+
+		case 3:
+			sv.type = mvt_double;
+			sv.s = std::to_string(pbf.get_uint64());
+			break;
+
+		case 4:
+			sv.type = mvt_double;
+			sv.s = std::to_string(-(long long) pbf.get_uint64());
+			break;
+
+		case 5:
+			sv.type = mvt_bool;
+			if (pbf.get_bool()) {
+				sv.s = "true";
+			} else {
+				sv.s = "false";
+			}
+			break;
+
+		case 6:
+			sv.type = mvt_string;  // stringified JSON
+			sv.s = pbf.get_string();
+
+			if (sv.s == "null") {
+				sv.type = mvt_null;
+			}
+
+			break;
+
+		default:
+			pbf.skip();
+		}
+	}
+
+	return sv;
+}
+
+drawvec readPoint(std::vector<long long> &coords, std::vector<int> &lengths, size_t dim, double e) {
+	ensureDim(dim);
+
+	long long x, y;
+	projection->project(coords[0] / e, coords[1] / e, 32, &x, &y);
+	drawvec dv;
+	dv.push_back(draw(VT_MOVETO, x, y));
+	return dv;
+}
+
+drawvec readLinePart(std::vector<long long> &coords, std::vector<int> &lengths, size_t dim, double e, size_t start, size_t end, bool closed) {
+	ensureDim(dim);
+
+	drawvec dv;
+	std::vector<long long> prev;
+	std::vector<double> p;
+	prev.resize(dim);
+	p.resize(dim);
+
+	for (size_t i = start; i + dim - 1 < end; i += dim) {
+		if (i + dim - 1 >= coords.size()) {
+			fprintf(stderr, "Internal error: line segment %zu vs %zu\n", i + dim - 1, coords.size());
+			exit(EXIT_FAILURE);
+		}
+
+		for (size_t d = 0; d < dim; d++) {
+			prev[d] += coords[i + d];
+			p[d] = prev[d] / e;
+		}
+
+		long long x, y;
+		projection->project(p[0], p[1], 32, &x, &y);
+
+		if (i == start) {
+			dv.push_back(draw(VT_MOVETO, x, y));
+		} else {
+			dv.push_back(draw(VT_LINETO, x, y));
+		}
+	}
+
+	if (closed && dv.size() > 0) {
+		dv.push_back(draw(VT_LINETO, dv[0].x, dv[0].y));
+	}
+
+	return dv;
+}
+
+drawvec readLine(std::vector<long long> &coords, std::vector<int> &lengths, size_t dim, double e, bool closed) {
+	return readLinePart(coords, lengths, dim, e, 0, coords.size(), closed);
+}
+
+drawvec readMultiLine(std::vector<long long> &coords, std::vector<int> &lengths, size_t dim, double e, bool closed) {
+	if (lengths.size() == 0) {
+		return readLinePart(coords, lengths, dim, e, 0, coords.size(), closed);
+	}
+
+	drawvec dv;
+	size_t here = 0;
+	for (size_t i = 0; i < lengths.size(); i++) {
+		drawvec dv2 = readLinePart(coords, lengths, dim, e, here, here + lengths[i] * dim, closed);
+		here += lengths[i] * dim;
+
+		for (size_t j = 0; j < dv2.size(); j++) {
+			dv.push_back(dv2[j]);
+		}
+	}
+
+	return dv;
+}
+
+drawvec readMultiPolygon(std::vector<long long> &coords, std::vector<int> &lengths, size_t dim, double e) {
+	ensureDim(dim);
+
+	if (lengths.size() == 0) {
+		return readLinePart(coords, lengths, dim, e, 0, coords.size(), true);
+	}
+
+	size_t polys = lengths[0];
+	size_t n = 1;
+	size_t here = 0;
+	drawvec dv;
+
+	for (size_t i = 0; i < polys; i++) {
+		size_t rings = lengths[n++];
+
+		for (size_t j = 0; j < rings; j++) {
+			drawvec dv2 = readLinePart(coords, lengths, dim, e, here, here + lengths[n] * dim, true);
+			here += lengths[n] * dim;
+			n++;
+
+			for (size_t k = 0; k < dv2.size(); k++) {
+				dv.push_back(dv2[k]);
+			}
+		}
+
+		dv.push_back(draw(VT_CLOSEPATH, 0, 0));  // mark that the next ring is outer
+	}
+
+	return dv;
+}
+
+struct drawvec_type {
+	drawvec dv;
+	int type;
+};
+
+std::vector<drawvec_type> readGeometry(protozero::pbf_reader &pbf, size_t dim, double e, std::vector<std::string> &keys) {
+	std::vector<drawvec_type> ret;
+	std::vector<long long> coords;
+	std::vector<int> lengths;
+	int type = -1;
+
+	while (pbf.next()) {
+		switch (pbf.tag()) {
+		case 1:
+			type = pbf.get_enum();
+			break;
+
+		case 2: {
+			auto pi = pbf.get_packed_uint32();
+			for (auto it = pi.first; it != pi.second; ++it) {
+				lengths.push_back(*it);
+			}
+			break;
+		}
+
+		case 3: {
+			auto pi = pbf.get_packed_sint64();
+			for (auto it = pi.first; it != pi.second; ++it) {
+				coords.push_back(*it);
+			}
+			break;
+		}
+
+		case 4: {
+			protozero::pbf_reader geometry_reader(pbf.get_message());
+			std::vector<drawvec_type> dv2 = readGeometry(geometry_reader, dim, e, keys);
+
+			for (size_t i = 0; i < dv2.size(); i++) {
+				ret.push_back(dv2[i]);
+			}
+
+			break;
+		}
+
+		default:
+			pbf.skip();
+		}
+	}
+
+	drawvec_type dv;
+	if (type == POINT) {
+		dv.dv = readPoint(coords, lengths, dim, e);
+	} else if (type == MULTIPOINT) {
+		dv.dv = readLine(coords, lengths, dim, e, false);
+	} else if (type == LINESTRING) {
+		dv.dv = readLine(coords, lengths, dim, e, false);
+	} else if (type == POLYGON) {
+		dv.dv = readMultiLine(coords, lengths, dim, e, true);
+	} else if (type == MULTIPOLYGON) {
+		dv.dv = readMultiPolygon(coords, lengths, dim, e);
+	} else {
+		// GeometryCollection
+		return ret;
+	}
+
+	dv.type = type / 2 + 1;
+	ret.push_back(dv);
+	return ret;
+}
+
+void readFeature(protozero::pbf_reader &pbf, size_t dim, double e, std::vector<std::string> &keys, struct serialization_state *sst, int layer, std::string layername) {
+	std::vector<drawvec_type> dv;
+	long long id = 0;
+	bool has_id = false;
+	std::vector<serial_val> values;
+	std::map<std::string, serial_val> other;
+
+	std::vector<std::string> full_keys;
+	std::vector<serial_val> full_values;
+
+	while (pbf.next()) {
+		switch (pbf.tag()) {
+		case 1: {
+			protozero::pbf_reader geometry_reader(pbf.get_message());
+			std::vector<drawvec_type> dv2 = readGeometry(geometry_reader, dim, e, keys);
+			for (size_t i = 0; i < dv2.size(); i++) {
+				dv.push_back(dv2[i]);
+			}
+			break;
+		}
+
+		case 11: {
+			static bool warned = false;
+			if (!warned) {
+				fprintf(stderr, "Non-numeric feature IDs not supported\n");
+				warned = true;
+			}
+			pbf.skip();
+			break;
+		}
+
+		case 12:
+			has_id = true;
+			id = pbf.get_sint64();
+			if (id < 0) {
+				static bool warned = false;
+				if (!warned) {
+					fprintf(stderr, "Out of range feature id %lld\n", id);
+					warned = true;
+				}
+				has_id = false;
+			}
+			break;
+
+		case 13: {
+			protozero::pbf_reader value_reader(pbf.get_message());
+			values.push_back(readValue(value_reader, keys));
+			break;
+		}
+
+		case 14: {
+			std::vector<size_t> properties;
+			auto pi = pbf.get_packed_uint32();
+			for (auto it = pi.first; it != pi.second; ++it) {
+				properties.push_back(*it);
+			}
+
+			for (size_t i = 0; i + 1 < properties.size(); i += 2) {
+				if (properties[i] >= keys.size()) {
+					fprintf(stderr, "Out of bounds key: %zu in %zu\n", properties[i], keys.size());
+					exit(EXIT_FAILURE);
+				}
+
+				if (properties[i + 1] >= values.size()) {
+					fprintf(stderr, "Out of bounds value: %zu in %zu\n", properties[i + 1], values.size());
+					exit(EXIT_FAILURE);
+				}
+
+				full_keys.push_back(keys[properties[i]]);
+				full_values.push_back(values[properties[i + 1]]);
+			}
+
+			values.clear();
+			break;
+		}
+
+		case 15: {
+			std::vector<size_t> misc;
+			auto pi = pbf.get_packed_uint32();
+			for (auto it = pi.first; it != pi.second; ++it) {
+				misc.push_back(*it);
+			}
+
+			for (size_t i = 0; i + 1 < misc.size(); i += 2) {
+				if (misc[i] >= keys.size()) {
+					fprintf(stderr, "Out of bounds key: %zu in %zu\n", misc[i], keys.size());
+					exit(EXIT_FAILURE);
+				}
+
+				if (misc[i + 1] >= values.size()) {
+					fprintf(stderr, "Out of bounds value: %zu in %zu\n", misc[i + 1], values.size());
+					exit(EXIT_FAILURE);
+				}
+
+				other.insert(std::pair<std::string, serial_val>(keys[misc[i]], values[misc[i + 1]]));
+			}
+
+			values.clear();
+			break;
+		}
+
+		default:
+			pbf.skip();
+		}
+	}
+
+	for (size_t i = 0; i < dv.size(); i++) {
+		serial_feature sf;
+
+		sf.layer = layer;
+		sf.layername = layername;
+		sf.segment = sst->segment;
+		sf.has_id = has_id;
+		sf.id = id;
+		sf.has_tippecanoe_minzoom = false;
+		sf.has_tippecanoe_maxzoom = false;
+		sf.feature_minzoom = false;
+		sf.seq = *(sst->layer_seq);
+		sf.geometry = dv[i].dv;
+		sf.t = dv[i].type;
+		sf.full_keys = full_keys;
+		sf.full_values = full_values;
+		sf.m = sf.full_values.size();
+
+		auto tip = other.find("tippecanoe");
+		if (tip != other.end()) {
+			json_pull *jp = json_begin_string(tip->second.s.c_str());
+			json_object *o = json_read_tree(jp);
+
+			if (o != NULL) {
+				json_object *min = json_hash_get(o, "minzoom");
+				if (min != NULL && (min->type == JSON_STRING || min->type == JSON_NUMBER)) {
+					sf.has_tippecanoe_minzoom = true;
+					sf.tippecanoe_minzoom = atoi(min->string);
+				}
+
+				json_object *max = json_hash_get(o, "maxzoom");
+				if (max != NULL && (max->type == JSON_STRING || max->type == JSON_NUMBER)) {
+					sf.has_tippecanoe_maxzoom = true;
+					sf.tippecanoe_maxzoom = atoi(max->string);
+				}
+
+				json_object *tlayer = json_hash_get(o, "layer");
+				if (tlayer != NULL && (tlayer->type == JSON_STRING || tlayer->type == JSON_NUMBER)) {
+					sf.layername = tlayer->string;
+				}
+			}
+
+			json_free(o);
+			json_end(jp);
+		}
+
+		serialize_feature(sst, sf);
+	}
+}
+
+struct queue_run_arg {
+	size_t start;
+	size_t end;
+	size_t segment;
+};
+
+void *run_parse_feature(void *v) {
+	struct queue_run_arg *qra = (struct queue_run_arg *) v;
+
+	for (size_t i = qra->start; i < qra->end; i++) {
+		struct queued_feature &qf = feature_queue[i];
+		readFeature(qf.pbf, qf.dim, qf.e, *qf.keys, &qf.sst[qra->segment], qf.layer, qf.layername);
+	}
+
+	return NULL;
+}
+
+void runQueue() {
+	if (feature_queue.size() == 0) {
+		return;
+	}
+
+	struct queue_run_arg qra[CPUS];
+	pthread_t pthreads[CPUS];
+
+	for (size_t i = 0; i < CPUS; i++) {
+		*(feature_queue[0].sst[i].layer_seq) = *(feature_queue[0].sst[0].layer_seq) + feature_queue.size() * i / CPUS;
+
+		qra[i].start = feature_queue.size() * i / CPUS;
+		qra[i].end = feature_queue.size() * (i + 1) / CPUS;
+		qra[i].segment = i;
+
+		if (pthread_create(&pthreads[i], NULL, run_parse_feature, &qra[i]) != 0) {
+			perror("pthread_create");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	for (size_t i = 0; i < CPUS; i++) {
+		void *retval;
+
+		if (pthread_join(pthreads[i], &retval) != 0) {
+			perror("pthread_join");
+		}
+	}
+
+	*(feature_queue[0].sst[0].layer_seq) = *(feature_queue[0].sst[CPUS - 1].layer_seq);
+	feature_queue.clear();
+}
+
+void queueFeature(protozero::pbf_reader &pbf, size_t dim, double e, std::vector<std::string> &keys, struct serialization_state *sst, int layer, std::string layername) {
+	struct queued_feature qf;
+	qf.pbf = pbf;
+	qf.dim = dim;
+	qf.e = e;
+	qf.keys = &keys;
+	qf.sst = sst;
+	qf.layer = layer;
+	qf.layername = layername;
+
+	feature_queue.push_back(qf);
+
+	if (feature_queue.size() > CPUS * 500) {
+		runQueue();
+	}
+}
+
+void outBareGeometry(drawvec const &dv, int type, size_t dim, double e, std::vector<std::string> &keys, struct serialization_state *sst, int layer, std::string layername) {
+	serial_feature sf;
+
+	sf.layer = layer;
+	sf.layername = layername;
+	sf.segment = sst->segment;
+	sf.has_id = false;
+	sf.has_tippecanoe_minzoom = false;
+	sf.has_tippecanoe_maxzoom = false;
+	sf.feature_minzoom = false;
+	sf.seq = (*sst->layer_seq);
+	sf.geometry = dv;
+	sf.t = type;
+	sf.m = 0;
+
+	serialize_feature(sst, sf);
+}
+
+void readFeatureCollection(protozero::pbf_reader &pbf, size_t dim, double e, std::vector<std::string> &keys, struct serialization_state *sst, int layer, std::string layername) {
+	while (pbf.next()) {
+		switch (pbf.tag()) {
+		case 1: {
+			protozero::pbf_reader feature_reader(pbf.get_message());
+			queueFeature(feature_reader, dim, e, keys, sst, layer, layername);
+			break;
+		}
+
+		default:
+			pbf.skip();
+		}
+	}
+}
+
+void parse_geobuf(struct serialization_state *sst, const char *src, size_t len, int layer, std::string layername) {
+	protozero::pbf_reader pbf(src, len);
+
+	size_t dim = 2;
+	double e = 1e6;
+	std::vector<std::string> keys;
+
+	while (pbf.next()) {
+		switch (pbf.tag()) {
+		case 1:
+			keys.push_back(pbf.get_string());
+			break;
+
+		case 2:
+			dim = pbf.get_int64();
+			break;
+
+		case 3:
+			e = pow(10, pbf.get_int64());
+			break;
+
+		case 4: {
+			protozero::pbf_reader feature_collection_reader(pbf.get_message());
+			readFeatureCollection(feature_collection_reader, dim, e, keys, sst, layer, layername);
+			break;
+		}
+
+		case 5: {
+			protozero::pbf_reader feature_reader(pbf.get_message());
+			queueFeature(feature_reader, dim, e, keys, sst, layer, layername);
+			break;
+		}
+
+		case 6: {
+			protozero::pbf_reader geometry_reader(pbf.get_message());
+			std::vector<drawvec_type> dv = readGeometry(geometry_reader, dim, e, keys);
+			for (size_t i = 0; i < dv.size(); i++) {
+				outBareGeometry(dv[i].dv, dv[i].type, dim, e, keys, sst, layer, layername);
+			}
+			break;
+		}
+
+		default:
+			pbf.skip();
+		}
+	}
+
+	runQueue();
+}

geobuf.hpp

@@ -0,0 +1,13 @@
+#ifndef GEOBUF_HPP
+#define GEOBUF_HPP
+
+#include <stdio.h>
+#include <set>
+#include <map>
+#include <string>
+#include "mbtiles.hpp"
+#include "serial.hpp"
+
+void parse_geobuf(struct serialization_state *sst, const char *s, size_t len, int layer, std::string layername);
+
+#endif

geojson.cpp

@@ -0,0 +1,397 @@
+#ifdef MTRACE
+#include <mcheck.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <string.h>
+#include <fcntl.h>
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <sqlite3.h>
+#include <stdarg.h>
+#include <sys/resource.h>
+#include <pthread.h>
+#include <vector>
+#include <algorithm>
+#include <set>
+#include <map>
+#include <string>
+#include "jsonpull/jsonpull.h"
+#include "pool.hpp"
+#include "projection.hpp"
+#include "memfile.hpp"
+#include "main.hpp"
+#include "mbtiles.hpp"
+#include "geojson.hpp"
+#include "geometry.hpp"
+#include "options.hpp"
+#include "serial.hpp"
+#include "text.hpp"
+#include "read_json.hpp"
+#include "mvt.hpp"
+
+int serialize_geojson_feature(struct serialization_state *sst, json_object *geometry, json_object *properties, json_object *id, int layer, json_object *tippecanoe, json_object *feature, std::string layername) {
+	json_object *geometry_type = json_hash_get(geometry, "type");
+	if (geometry_type == NULL) {
+		static int warned = 0;
+		if (!warned) {
+			fprintf(stderr, "%s:%d: null geometry (additional not reported)\n", sst->fname, sst->line);
+			json_context(feature);
+			warned = 1;
+		}
+
+		return 0;
+	}
+
+	if (geometry_type->type != JSON_STRING) {
+		fprintf(stderr, "%s:%d: geometry type is not a string\n", sst->fname, sst->line);
+		json_context(feature);
+		return 0;
+	}
+
+	json_object *coordinates = json_hash_get(geometry, "coordinates");
+	if (coordinates == NULL || coordinates->type != JSON_ARRAY) {
+		fprintf(stderr, "%s:%d: feature without coordinates array\n", sst->fname, sst->line);
+		json_context(feature);
+		return 0;
+	}
+
+	int t;
+	for (t = 0; t < GEOM_TYPES; t++) {
+		if (strcmp(geometry_type->string, geometry_names[t]) == 0) {
+			break;
+		}
+	}
+	if (t >= GEOM_TYPES) {
+		fprintf(stderr, "%s:%d: Can't handle geometry type %s\n", sst->fname, sst->line, geometry_type->string);
+		json_context(feature);
+		return 0;
+	}
+
+	int tippecanoe_minzoom = -1;
+	int tippecanoe_maxzoom = -1;
+	std::string tippecanoe_layername;
+
+	if (tippecanoe != NULL) {
+		json_object *min = json_hash_get(tippecanoe, "minzoom");
+		if (min != NULL && min->type == JSON_NUMBER) {
+			tippecanoe_minzoom = min->number;
+		}
+		if (min != NULL && min->type == JSON_STRING) {
+			tippecanoe_minzoom = atoi(min->string);
+		}
+
+		json_object *max = json_hash_get(tippecanoe, "maxzoom");
+		if (max != NULL && max->type == JSON_NUMBER) {
+			tippecanoe_maxzoom = max->number;
+		}
+		if (max != NULL && max->type == JSON_STRING) {
+			tippecanoe_maxzoom = atoi(max->string);
+		}
+
+		json_object *ln = json_hash_get(tippecanoe, "layer");
+		if (ln != NULL && (ln->type == JSON_STRING || ln->type == JSON_NUMBER)) {
+			tippecanoe_layername = std::string(ln->string);
+		}
+	}
+
+	bool has_id = false;
+	unsigned long long id_value = 0;
+	if (id != NULL) {
+		if (id->type == JSON_NUMBER) {
+			if (id->number >= 0) {
+				char *err = NULL;
+				id_value = strtoull(id->string, &err, 10);
+
+				if (err != NULL && *err != '\0') {
+					static bool warned_frac = false;
+
+					if (!warned_frac) {
+						fprintf(stderr, "Warning: Can't represent non-integer feature ID %s\n", id->string);
+						warned_frac = true;
+					}
+				} else {
+					has_id = true;
+				}
+			} else {
+				static bool warned_neg = false;
+
+				if (!warned_neg) {
+					fprintf(stderr, "Warning: Can't represent negative feature ID %s\n", id->string);
+					warned_neg = true;
+				}
+			}
+		} else {
+			static bool warned_nan = false;
+
+			if (!warned_nan) {
+				char *s = json_stringify(id);
+				fprintf(stderr, "Warning: Can't represent non-numeric feature ID %s\n", s);
+				free(s);  // stringify
+				warned_nan = true;
+			}
+		}
+	}
+
+	size_t nprop = 0;
+	if (properties != NULL && properties->type == JSON_HASH) {
+		nprop = properties->length;
+	}
+
+	char *metakey[nprop];
+	std::vector<std::string> metaval;
+	metaval.resize(nprop);
+	int metatype[nprop];
+	size_t m = 0;
+
+	for (size_t i = 0; i < nprop; i++) {
+		if (properties->keys[i]->type == JSON_STRING) {
+			std::string s(properties->keys[i]->string);
+
+			int type = -1;
+			std::string val;
+			stringify_value(properties->values[i], type, val, sst->fname, sst->line, feature, properties->keys[i]->string);
+
+			if (type >= 0) {
+				metakey[m] = properties->keys[i]->string;
+				metatype[m] = type;
+				metaval[m] = val;
+				m++;
+			} else {
+				metakey[m] = properties->keys[i]->string;
+				metatype[m] = mvt_null;
+				metaval[m] = "null";
+				m++;
+			}
+		}
+	}
+
+	drawvec dv;
+	parse_geometry(t, coordinates, dv, VT_MOVETO, sst->fname, sst->line, feature);
+
+	serial_feature sf;
+	sf.layer = layer;
+	sf.segment = sst->segment;
+	sf.t = mb_geometry[t];
+	sf.has_id = has_id;
+	sf.id = id_value;
+	sf.has_tippecanoe_minzoom = (tippecanoe_minzoom != -1);
+	sf.tippecanoe_minzoom = tippecanoe_minzoom;
+	sf.has_tippecanoe_maxzoom = (tippecanoe_maxzoom != -1);
+	sf.tippecanoe_maxzoom = tippecanoe_maxzoom;
+	sf.geometry = dv;
+	sf.m = m;
+	sf.feature_minzoom = 0;  // Will be filled in during index merging
+	sf.seq = *(sst->layer_seq);
+
+	if (tippecanoe_layername.size() != 0) {
+		sf.layername = tippecanoe_layername;
+	} else {
+		sf.layername = layername;
+	}
+
+	for (size_t i = 0; i < m; i++) {
+		sf.full_keys.push_back(metakey[i]);
+
+		serial_val sv;
+		sv.type = metatype[i];
+		sv.s = metaval[i];
+
+		sf.full_values.push_back(sv);
+	}
+
+	return serialize_feature(sst, sf);
+}
+
+void check_crs(json_object *j, const char *reading) {
+	json_object *crs = json_hash_get(j, "crs");
+	if (crs != NULL) {
+		json_object *properties = json_hash_get(crs, "properties");
+		if (properties != NULL) {
+			json_object *name = json_hash_get(properties, "name");
+			if (name->type == JSON_STRING) {
+				if (strcmp(name->string, projection->alias) != 0) {
+					fprintf(stderr, "%s: Warning: GeoJSON specified projection \"%s\", not the expected \"%s\".\n", reading, name->string, projection->alias);
+					fprintf(stderr, "%s: If \"%s\" is not the expected projection, use -s to specify the right one.\n", reading, projection->alias);
+				}
+			}
+		}
+	}
+}
+
+void parse_json(struct serialization_state *sst, json_pull *jp, int layer, std::string layername) {
+	long long found_hashes = 0;
+	long long found_features = 0;
+	long long found_geometries = 0;
+
+	while (1) {
+		json_object *j = json_read(jp);
+		if (j == NULL) {
+			if (jp->error != NULL) {
+				fprintf(stderr, "%s:%d: %s\n", sst->fname, jp->line, jp->error);
+				if (jp->root != NULL) {
+					json_context(jp->root);
+				}
+			}
+
+			json_free(jp->root);
+			break;
+		}
+
+		if (j->type == JSON_HASH) {
+			found_hashes++;
+
+			if (found_hashes == 50 && found_features == 0 && found_geometries == 0) {
+				fprintf(stderr, "%s:%d: Warning: not finding any GeoJSON features or geometries in input yet after 50 objects.\n", sst->fname, jp->line);
+			}
+		}
+
+		json_object *type = json_hash_get(j, "type");
+		if (type == NULL || type->type != JSON_STRING) {
+			continue;
+		}
+
+		if (found_features == 0) {
+			int i;
+			int is_geometry = 0;
+			for (i = 0; i < GEOM_TYPES; i++) {
+				if (strcmp(type->string, geometry_names[i]) == 0) {
+					is_geometry = 1;
+					break;
+				}
+			}
+
+			if (is_geometry) {
+				if (j->parent != NULL) {
+					if (j->parent->type == JSON_ARRAY) {
+						if (j->parent->parent->type == JSON_HASH) {
+							json_object *geometries = json_hash_get(j->parent->parent, "geometries");
+							if (geometries != NULL) {
+								// Parent of Parent must be a GeometryCollection
+								is_geometry = 0;
+							}
+						}
+					} else if (j->parent->type == JSON_HASH) {
+						json_object *geometry = json_hash_get(j->parent, "geometry");
+						if (geometry != NULL) {
+							// Parent must be a Feature
+							is_geometry = 0;
+						}
+					}
+				}
+			}
+
+			if (is_geometry) {
+				if (found_features != 0 && found_geometries == 0) {
+					fprintf(stderr, "%s:%d: Warning: found a mixture of features and bare geometries\n", sst->fname, jp->line);
+				}
+				found_geometries++;
+
+				serialize_geojson_feature(sst, j, NULL, NULL, layer, NULL, j, layername);
+				json_free(j);
+				continue;
+			}
+		}
+
+		if (strcmp(type->string, "Feature") != 0) {
+			if (strcmp(type->string, "FeatureCollection") == 0) {
+				check_crs(j, sst->fname);
+				json_free(j);
+			}
+
+			continue;
+		}
+
+		if (found_features == 0 && found_geometries != 0) {
+			fprintf(stderr, "%s:%d: Warning: found a mixture of features and bare geometries\n", sst->fname, jp->line);
+		}
+		found_features++;
+
+		json_object *geometry = json_hash_get(j, "geometry");
+		if (geometry == NULL) {
+			fprintf(stderr, "%s:%d: feature with no geometry\n", sst->fname, jp->line);
+			json_context(j);
+			json_free(j);
+			continue;
+		}
+
+		json_object *properties = json_hash_get(j, "properties");
+		if (properties == NULL || (properties->type != JSON_HASH && properties->type != JSON_NULL)) {
+			fprintf(stderr, "%s:%d: feature without properties hash\n", sst->fname, jp->line);
+			json_context(j);
+			json_free(j);
+			continue;
+		}
+
+		json_object *tippecanoe = json_hash_get(j, "tippecanoe");
+		json_object *id = json_hash_get(j, "id");
+
+		json_object *geometries = json_hash_get(geometry, "geometries");
+		if (geometries != NULL) {
+			size_t g;
+			for (g = 0; g < geometries->length; g++) {
+				serialize_geojson_feature(sst, geometries->array[g], properties, id, layer, tippecanoe, j, layername);
+			}
+		} else {
+			serialize_geojson_feature(sst, geometry, properties, id, layer, tippecanoe, j, layername);
+		}
+
+		json_free(j);
+
+		/* XXX check for any non-features in the outer object */
+	}
+}
+
+void *run_parse_json(void *v) {
+	struct parse_json_args *pja = (struct parse_json_args *) v;
+
+	parse_json(pja->sst, pja->jp, pja->layer, *pja->layername);
+
+	return NULL;
+}
+
+struct jsonmap {
+	char *map;
+	unsigned long long off;
+	unsigned long long end;
+};
+
+ssize_t json_map_read(struct json_pull *jp, char *buffer, size_t n) {
+	struct jsonmap *jm = (struct jsonmap *) jp->source;
+
+	if (jm->off + n >= jm->end) {
+		n = jm->end - jm->off;
+	}
+
+	memcpy(buffer, jm->map + jm->off, n);
+	jm->off += n;
+
+	return n;
+}
+
+struct json_pull *json_begin_map(char *map, long long len) {
+	struct jsonmap *jm = new jsonmap;
+	if (jm == NULL) {
+		perror("Out of memory");
+		exit(EXIT_FAILURE);
+	}
+
+	jm->map = map;
+	jm->off = 0;
+	jm->end = len;
+
+	return json_begin(json_map_read, jm);
+}
+
+void json_end_map(struct json_pull *jp) {
+	delete (struct jsonmap *) jp->source;
+	json_end(jp);
+}

geojson.hpp

@@ -0,0 +1,28 @@
+#ifndef GEOJSON_HPP
+#define GEOJSON_HPP
+
+#include <stdio.h>
+#include <set>
+#include <map>
+#include <string>
+#include "mbtiles.hpp"
+#include "jsonpull/jsonpull.h"
+#include "serial.hpp"
+
+struct parse_json_args {
+	json_pull *jp;
+	int layer;
+	std::string *layername;
+	std::map<std::string, int> const *attribute_types;
+	bool want_dist;
+
+	struct serialization_state *sst;
+};
+
+struct json_pull *json_begin_map(char *map, long long len);
+void json_end_map(struct json_pull *jp);
+
+void parse_json(struct serialization_state *sst, json_pull *jp, int layer, std::string layername);
+void *run_parse_json(void *v);
+
+#endif

geojson2nd.cpp

@@ -0,0 +1,153 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <string.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <string>
+#include "jsonpull/jsonpull.h"
+
+int fail = EXIT_SUCCESS;
+bool wrap = false;
+
+std::string buffered;
+int buffered_type = -1;
+// 0: nothing yet
+// 1: buffered a line
+// 2: wrote the line and the wrapper
+int buffer_state = 0;
+
+void out(std::string s, int type) {
+	if (!wrap) {
+		printf("%s\n", s.c_str());
+		return;
+	}
+
+	if (buffer_state == 0) {
+		buffered = s;
+		buffered_type = type;
+		buffer_state = 1;
+		return;
+	}
+
+	if (buffer_state == 1) {
+		if (buffered_type == 1) {
+			printf("{\"type\":\"FeatureCollection\",\"features\":[\n");
+		} else {
+			printf("{\"type\":\"GeometryCollection\",\"geometries\":[\n");
+		}
+
+		printf("%s\n", buffered.c_str());
+		buffer_state = 2;
+	}
+
+	printf(",\n%s\n", s.c_str());
+
+	if (type != buffered_type) {
+		fprintf(stderr, "Error: mix of bare geometries and features\n");
+		exit(EXIT_FAILURE);
+	}
+}
+
+void process(FILE *fp, const char *fname) {
+	json_pull *jp = json_begin_file(fp);
+
+	while (1) {
+		json_object *j = json_read(jp);
+		if (j == NULL) {
+			if (jp->error != NULL) {
+				fprintf(stderr, "%s:%d: %s\n", fname, jp->line, jp->error);
+			}
+
+			json_free(jp->root);
+			break;
+		}
+
+		json_object *type = json_hash_get(j, "type");
+		if (type == NULL || type->type != JSON_STRING) {
+			continue;
+		}
+
+		if (strcmp(type->string, "Feature") == 0) {
+			char *s = json_stringify(j);
+			out(s, 1);
+			free(s);
+			json_free(j);
+		} else if (strcmp(type->string, "Point") == 0 ||
+			   strcmp(type->string, "MultiPoint") == 0 ||
+			   strcmp(type->string, "LineString") == 0 ||
+			   strcmp(type->string, "MultiLineString") == 0 ||
+			   strcmp(type->string, "MultiPolygon") == 0) {
+			int is_geometry = 1;
+
+			if (j->parent != NULL) {
+				if (j->parent->type == JSON_ARRAY) {
+					if (j->parent->parent->type == JSON_HASH) {
+						json_object *geometries = json_hash_get(j->parent->parent, "geometries");
+						if (geometries != NULL) {
+							// Parent of Parent must be a GeometryCollection
+							is_geometry = 0;
+						}
+					}
+				} else if (j->parent->type == JSON_HASH) {
+					json_object *geometry = json_hash_get(j->parent, "geometry");
+					if (geometry != NULL) {
+						// Parent must be a Feature
+						is_geometry = 0;
+					}
+				}
+			}
+
+			if (is_geometry) {
+				char *s = json_stringify(j);
+				out(s, 2);
+				free(s);
+				json_free(j);
+			}
+		} else if (strcmp(type->string, "FeatureCollection") == 0) {
+			json_free(j);
+		}
+	}
+
+	json_end(jp);
+}
+
+int main(int argc, char **argv) {
+	extern int optind;
+	int i;
+
+	while ((i = getopt(argc, argv, "w")) != -1) {
+		switch (i) {
+		case 'w':
+			wrap = true;
+			break;
+
+		default:
+			fprintf(stderr, "Unexpected option -%c\n", i);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	if (optind >= argc) {
+		process(stdin, "standard input");
+	} else {
+		for (i = optind; i < argc; i++) {
+			FILE *f = fopen(argv[i], "r");
+			if (f == NULL) {
+				perror(argv[i]);
+				exit(EXIT_FAILURE);
+			}
+
+			process(f, argv[i]);
+			fclose(f);
+		}
+	}
+
+	if (buffer_state == 1) {
+		printf("%s\n", buffered.c_str());
+	} else if (buffer_state == 2) {
+		printf("]}\n");
+	}
+
+	return fail;
+}

geometry.cc

@@ -1,696 +0,0 @@
-#include <iostream>
-#include <fstream>
-#include <string>
-#include <stack>
-#include <vector>
-#include <algorithm>
-#include <stdio.h>
-#include <unistd.h>
-#include <math.h>
-#include <sqlite3.h>
-#include <limits.h>
-#include "geometry.hh"
-#include "clipper/clipper.hpp"
-
-extern "C" {
-#include "tile.h"
-#include "clip.h"
-#include "projection.h"
-}
-
-drawvec decode_geometry(char **meta, int z, unsigned tx, unsigned ty, int detail, long long *bbox) {
-	drawvec out;
-
-	bbox[0] = LONG_LONG_MAX;
-	bbox[1] = LONG_LONG_MAX;
-	bbox[2] = LONG_LONG_MIN;
-	bbox[3] = LONG_LONG_MIN;
-
-	long long wx = initial_x, wy = initial_y;
-
-	while (1) {
-		draw d;
-
-		deserialize_byte(meta, &d.op);
-		if (d.op == VT_END) {
-			break;
-		}
-
-		if (d.op == VT_MOVETO || d.op == VT_LINETO) {
-			long long dx, dy;
-
-			deserialize_long_long(meta, &dx);
-			deserialize_long_long(meta, &dy);
-
-			wx += dx << geometry_scale;
-			wy += dy << geometry_scale;
-
-			long long wwx = wx;
-			long long wwy = wy;
-
-			if (z != 0) {
-				wwx -= tx << (32 - z);
-				wwy -= ty << (32 - z);
-			}
-
-			if (wwx < bbox[0]) {
-				bbox[0] = wwx;
-			}
-			if (wwy < bbox[1]) {
-				bbox[1] = wwy;
-			}
-			if (wwx > bbox[2]) {
-				bbox[2] = wwx;
-			}
-			if (wwy > bbox[3]) {
-				bbox[3] = wwy;
-			}
-
-			d.x = wwx;
-			d.y = wwy;
-		}
-
-		out.push_back(d);
-	}
-
-	return out;
-}
-
-void to_tile_scale(drawvec &geom, int z, int detail) {
-	unsigned i;
-
-	for (i = 0; i < geom.size(); i++) {
-		geom[i].x >>= (32 - detail - z);
-		geom[i].y >>= (32 - detail - z);
-	}
-}
-
-drawvec remove_noop(drawvec geom, int type, int shift) {
-	// first pass: remove empty linetos
-
-	long long x = 0, y = 0;
-	drawvec out;
-	unsigned i;
-
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_LINETO && (geom[i].x >> shift) == x && (geom[i].y >> shift) == y) {
-			continue;
-		}
-
-		if (geom[i].op == VT_CLOSEPATH) {
-			fprintf(stderr, "Shouldn't happen\n");
-			out.push_back(geom[i]);
-		} else { /* moveto or lineto */
-			out.push_back(geom[i]);
-			x = geom[i].x >> shift;
-			y = geom[i].y >> shift;
-		}
-	}
-
-	// second pass: remove unused movetos
-
-	geom = out;
-	out.resize(0);
-
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			if (i + 1 >= geom.size()) {
-				continue;
-			}
-
-			if (geom[i + 1].op == VT_MOVETO) {
-				continue;
-			}
-
-			if (geom[i + 1].op == VT_CLOSEPATH) {
-				fprintf(stderr, "Shouldn't happen\n");
-				i++;  // also remove unused closepath
-				continue;
-			}
-		}
-
-		out.push_back(geom[i]);
-	}
-
-	// second pass: remove empty movetos
-
-	if (type == VT_LINE) {
-		geom = out;
-		out.resize(0);
-
-		for (i = 0; i < geom.size(); i++) {
-			if (geom[i].op == VT_MOVETO) {
-				if (i > 0 && geom[i - 1].op == VT_LINETO && (geom[i - 1].x >> shift) == (geom[i].x >> shift) && (geom[i - 1].y >> shift) == (geom[i].y >> shift)) {
-					continue;
-				}
-			}
-
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-
-/* XXX */
-#if 0
-drawvec shrink_lines(drawvec &geom, int z, int detail, int basezoom, long long *here, double droprate) {
-	long long res = 200LL << (32 - 8 - z);
-	long long portion = res / exp(log(sqrt(droprate)) * (basezoom - z));
-
-	unsigned i;
-	drawvec out;
-
-	for (i = 0; i < geom.size(); i++) {
-		if (i > 0 && (geom[i - 1].op == VT_MOVETO || geom[i - 1].op == VT_LINETO) && geom[i].op == VT_LINETO) {
-			double dx = (geom[i].x - geom[i - 1].x);
-			double dy = (geom[i].y - geom[i - 1].y);
-			long long d = sqrt(dx * dx + dy * dy);
-
-			long long n;
-			long long next = LONG_LONG_MAX;
-			for (n = *here; n < *here + d; n = next) {
-				int within;
-
-				if (n % res < portion) {
-					next = (n / res) * res + portion;
-					within = 1;
-				} else {
-					next = (n / res + 1) * res;
-					within = 0;
-				}
-
-				if (next > *here + d) {
-					next = *here + d;
-				}
-
-				//printf("drawing from %lld to %lld in %lld\n", n - *here, next - *here, d);
-
-				double f1 = (n - *here) / (double) d;
-				double f2 = (next - *here) / (double) d;
-
-				if (within) {
-					out.push_back(draw(VT_MOVETO, geom[i - 1].x + f1 * (geom[i].x - geom[i - 1].x), geom[i - 1].y + f1 * (geom[i].y - geom[i - 1].y)));
-					out.push_back(draw(VT_LINETO, geom[i - 1].x + f2 * (geom[i].x - geom[i - 1].x), geom[i - 1].y + f2 * (geom[i].y - geom[i - 1].y)));
-				} else {
-					out.push_back(draw(VT_MOVETO, geom[i - 1].x + f2 * (geom[i].x - geom[i - 1].x), geom[i - 1].y + f2 * (geom[i].y - geom[i - 1].y)));
-				}
-			}
-
-			*here += d;
-		} else {
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-#endif
-
-static void decode_clipped(ClipperLib::PolyNode *t, drawvec &out) {
-	// To make the GeoJSON come out right, we need to do each of the
-	// outer rings followed by its children if any, and then go back
-	// to do any outer-ring children of those children as a new top level.
-
-	ClipperLib::Path p = t->Contour;
-	for (unsigned i = 0; i < p.size(); i++) {
-		out.push_back(draw((i == 0) ? VT_MOVETO : VT_LINETO, p[i].X, p[i].Y));
-	}
-	if (p.size() > 0) {
-		out.push_back(draw(VT_LINETO, p[0].X, p[0].Y));
-	}
-
-	for (int n = 0; n < t->ChildCount(); n++) {
-		ClipperLib::Path p = t->Childs[n]->Contour;
-		for (unsigned i = 0; i < p.size(); i++) {
-			out.push_back(draw((i == 0) ? VT_MOVETO : VT_LINETO, p[i].X, p[i].Y));
-		}
-		if (p.size() > 0) {
-			out.push_back(draw(VT_LINETO, p[0].X, p[0].Y));
-		}
-	}
-
-	for (int n = 0; n < t->ChildCount(); n++) {
-		for (int m = 0; m < t->Childs[n]->ChildCount(); m++) {
-			decode_clipped(t->Childs[n]->Childs[m], out);
-		}
-	}
-}
-
-drawvec clean_or_clip_poly(drawvec &geom, int z, int detail, int buffer, bool clip) {
-	ClipperLib::Clipper clipper(ClipperLib::ioStrictlySimple);
-
-	for (unsigned i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			unsigned j;
-			for (j = i + 1; j < geom.size(); j++) {
-				if (geom[j].op != VT_LINETO) {
-					break;
-				}
-			}
-
-			ClipperLib::Path path;
-
-			drawvec tmp;
-			for (unsigned k = i; k < j; k++) {
-				path.push_back(ClipperLib::IntPoint(geom[k].x, geom[k].y));
-			}
-
-			if (!clipper.AddPath(path, ClipperLib::ptSubject, true)) {
-#if 0
-				fprintf(stderr, "Couldn't add polygon for clipping:");
-				for (unsigned k = i; k < j; k++) {
-					fprintf(stderr, " %lld,%lld", geom[k].x, geom[k].y);
-				}
-				fprintf(stderr, "\n");
-#endif
-			}
-
-			i = j - 1;
-		} else {
-			fprintf(stderr, "Unexpected operation in polygon %d\n", (int) geom[i].op);
-			exit(EXIT_FAILURE);
-		}
-	}
-
-	if (clip) {
-		long long area = 0xFFFFFFFF;
-		if (z != 0) {
-			area = 1LL << (32 - z);
-		}
-		long long clip_buffer = buffer * area / 256;
-
-		ClipperLib::Path edge;
-		edge.push_back(ClipperLib::IntPoint(-clip_buffer, -clip_buffer));
-		edge.push_back(ClipperLib::IntPoint(area + clip_buffer, -clip_buffer));
-		edge.push_back(ClipperLib::IntPoint(area + clip_buffer, area + clip_buffer));
-		edge.push_back(ClipperLib::IntPoint(-clip_buffer, area + clip_buffer));
-		edge.push_back(ClipperLib::IntPoint(-clip_buffer, -clip_buffer));
-
-		clipper.AddPath(edge, ClipperLib::ptClip, true);
-	}
-
-	ClipperLib::PolyTree clipped;
-	if (clip) {
-		if (!clipper.Execute(ClipperLib::ctIntersection, clipped)) {
-			fprintf(stderr, "Polygon clip failed\n");
-		}
-	} else {
-		if (!clipper.Execute(ClipperLib::ctUnion, clipped)) {
-			fprintf(stderr, "Polygon clean failed\n");
-		}
-	}
-
-	drawvec out;
-
-	for (int i = 0; i < clipped.ChildCount(); i++) {
-		decode_clipped(clipped.Childs[i], out);
-	}
-
-	return out;
-}
-
-drawvec reduce_tiny_poly(drawvec &geom, int z, int detail, bool *reduced, double *accum_area) {
-	drawvec out;
-	long long pixel = (1 << (32 - detail - z)) * 2;
-
-	*reduced = true;
-
-	for (unsigned i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			unsigned j;
-			for (j = i + 1; j < geom.size(); j++) {
-				if (geom[j].op != VT_LINETO) {
-					break;
-				}
-			}
-
-			double area = 0;
-			for (unsigned k = i; k < j; k++) {
-				area += geom[k].x * geom[i + ((k - i + 1) % (j - i))].y;
-				area -= geom[k].y * geom[i + ((k - i + 1) % (j - i))].x;
-			}
-			area = area / 2;
-
-			if (fabs(area) <= pixel * pixel) {
-				// printf("area is only %f vs %lld so using square\n", area, pixel * pixel);
-
-				*accum_area += area;
-				if (*accum_area > pixel * pixel) {
-					// XXX use centroid;
-
-					out.push_back(draw(VT_MOVETO, geom[i].x - pixel / 2, geom[i].y - pixel / 2));
-					out.push_back(draw(VT_LINETO, geom[i].x + pixel / 2, geom[i].y - pixel / 2));
-					out.push_back(draw(VT_LINETO, geom[i].x + pixel / 2, geom[i].y + pixel / 2));
-					out.push_back(draw(VT_LINETO, geom[i].x - pixel / 2, geom[i].y + pixel / 2));
-					out.push_back(draw(VT_LINETO, geom[i].x - pixel / 2, geom[i].y - pixel / 2));
-
-					*accum_area -= pixel * pixel;
-				}
-			} else {
-				// printf("area is %f so keeping instead of %lld\n", area, pixel * pixel);
-
-				for (unsigned k = i; k <= j && k < geom.size(); k++) {
-					out.push_back(geom[k]);
-				}
-
-				*reduced = false;
-			}
-
-			i = j - 1;
-		} else {
-			fprintf(stderr, "how did we get here with %d in %d?\n", geom[i].op, (int) geom.size());
-
-			for (unsigned n = 0; n < geom.size(); n++) {
-				fprintf(stderr, "%d/%lld/%lld ", geom[n].op, geom[n].x, geom[n].y);
-			}
-			fprintf(stderr, "\n");
-
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-
-drawvec clip_point(drawvec &geom, int z, int detail, long long buffer) {
-	drawvec out;
-	unsigned i;
-
-	long long min = 0;
-	long long area = 0xFFFFFFFF;
-	if (z != 0) {
-		area = 1LL << (32 - z);
-
-		min -= buffer * area / 256;
-		area += buffer * area / 256;
-	}
-
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].x >= min && geom[i].y >= min && geom[i].x <= area && geom[i].y <= area) {
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-
-int quick_check(long long *bbox, int z, int detail, long long buffer) {
-	long long min = 0;
-	long long area = 0xFFFFFFFF;
-	if (z != 0) {
-		area = 1LL << (32 - z);
-
-		min -= buffer * area / 256;
-		area += buffer * area / 256;
-	}
-
-	// bbox entirely outside the tile
-	if (bbox[0] > area || bbox[1] > area) {
-		return 0;
-	}
-	if (bbox[2] < min || bbox[3] < min) {
-		return 0;
-	}
-
-	// bbox entirely within the tile
-	if (bbox[0] > min && bbox[1] > min && bbox[2] < area && bbox[3] < area) {
-		return 1;
-	}
-
-	// some overlap of edge
-	return 2;
-}
-
-drawvec clip_lines(drawvec &geom, int z, int detail, long long buffer) {
-	drawvec out;
-	unsigned i;
-
-	long long min = 0;
-	long long area = 0xFFFFFFFF;
-	if (z != 0) {
-		area = 1LL << (32 - z);
-
-		min -= buffer * area / 256;
-		area += buffer * area / 256;
-	}
-
-	for (i = 0; i < geom.size(); i++) {
-		if (i > 0 && (geom[i - 1].op == VT_MOVETO || geom[i - 1].op == VT_LINETO) && geom[i].op == VT_LINETO) {
-			double x1 = geom[i - 1].x;
-			double y1 = geom[i - 1].y;
-
-			double x2 = geom[i - 0].x;
-			double y2 = geom[i - 0].y;
-
-			int c = clip(&x1, &y1, &x2, &y2, min, min, area, area);
-
-			if (c > 1) {  // clipped
-				out.push_back(draw(VT_MOVETO, x1, y1));
-				out.push_back(draw(VT_LINETO, x2, y2));
-				out.push_back(draw(VT_MOVETO, geom[i].x, geom[i].y));
-			} else if (c == 1) {  // unchanged
-				out.push_back(geom[i]);
-			} else {  // clipped away entirely
-				out.push_back(draw(VT_MOVETO, geom[i].x, geom[i].y));
-			}
-		} else {
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-
-static double square_distance_from_line(long long point_x, long long point_y, long long segA_x, long long segA_y, long long segB_x, long long segB_y) {
-	double p2x = segB_x - segA_x;
-	double p2y = segB_y - segA_y;
-	double something = p2x * p2x + p2y * p2y;
-	double u = 0 == something ? 0 : ((point_x - segA_x) * p2x + (point_y - segA_y) * p2y) / something;
-
-	if (u > 1) {
-		u = 1;
-	} else if (u < 0) {
-		u = 0;
-	}
-
-	double x = segA_x + u * p2x;
-	double y = segA_y + u * p2y;
-
-	double dx = x - point_x;
-	double dy = y - point_y;
-
-	return dx * dx + dy * dy;
-}
-
-// https://github.com/Project-OSRM/osrm-backend/blob/733d1384a40f/Algorithms/DouglasePeucker.cpp
-static void douglas_peucker(drawvec &geom, int start, int n, double e) {
-	e = e * e;
-	std::stack<int> recursion_stack;
-
-	{
-		int left_border = 0;
-		int right_border = 1;
-		// Sweep linerarily over array and identify those ranges that need to be checked
-		do {
-			if (geom[start + right_border].necessary) {
-				recursion_stack.push(left_border);
-				recursion_stack.push(right_border);
-				left_border = right_border;
-			}
-			++right_border;
-		} while (right_border < n);
-	}
-
-	while (!recursion_stack.empty()) {
-		// pop next element
-		int second = recursion_stack.top();
-		recursion_stack.pop();
-		int first = recursion_stack.top();
-		recursion_stack.pop();
-
-		double max_distance = -1;
-		int farthest_element_index = second;
-
-		// find index idx of element with max_distance
-		int i;
-		for (i = first + 1; i < second; i++) {
-			double temp_dist = square_distance_from_line(geom[start + i].x, geom[start + i].y, geom[start + first].x, geom[start + first].y, geom[start + second].x, geom[start + second].y);
-
-			double distance = fabs(temp_dist);
-
-			if (distance > e && distance > max_distance) {
-				farthest_element_index = i;
-				max_distance = distance;
-			}
-		}
-
-		if (max_distance > e) {
-			// mark idx as necessary
-			geom[start + farthest_element_index].necessary = 1;
-
-			if (1 < farthest_element_index - first) {
-				recursion_stack.push(first);
-				recursion_stack.push(farthest_element_index);
-			}
-			if (1 < second - farthest_element_index) {
-				recursion_stack.push(farthest_element_index);
-				recursion_stack.push(second);
-			}
-		}
-	}
-}
-
-drawvec simplify_lines(drawvec &geom, int z, int detail) {
-	int res = 1 << (32 - detail - z);
-
-	unsigned i;
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			geom[i].necessary = 1;
-		} else if (geom[i].op == VT_LINETO) {
-			geom[i].necessary = 0;
-		} else {
-			geom[i].necessary = 1;
-		}
-	}
-
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			unsigned j;
-			for (j = i + 1; j < geom.size(); j++) {
-				if (geom[j].op != VT_LINETO) {
-					break;
-				}
-			}
-
-			geom[i].necessary = 1;
-			geom[j - 1].necessary = 1;
-
-			douglas_peucker(geom, i, j - i, res);
-			i = j - 1;
-		}
-	}
-
-	drawvec out;
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].necessary) {
-			out.push_back(geom[i]);
-		}
-	}
-
-	return out;
-}
-
-drawvec reorder_lines(drawvec &geom) {
-	// Only reorder simple linestrings with a single moveto
-
-	if (geom.size() == 0) {
-		return geom;
-	}
-
-	unsigned i;
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_MOVETO) {
-			if (i != 0) {
-				return geom;
-			}
-		} else if (geom[i].op == VT_LINETO) {
-			if (i == 0) {
-				return geom;
-			}
-		} else {
-			return geom;
-		}
-	}
-
-	// Reorder anything that goes up and to the left
-	// instead of down and to the right
-	// so that it will coalesce better
-
-	unsigned long long l1 = encode(geom[0].x, geom[0].y);
-	unsigned long long l2 = encode(geom[geom.size() - 1].x, geom[geom.size() - 1].y);
-
-	if (l1 > l2) {
-		drawvec out;
-		for (i = 0; i < geom.size(); i++) {
-			out.push_back(geom[geom.size() - 1 - i]);
-		}
-		out[0].op = VT_MOVETO;
-		out[out.size() - 1].op = VT_LINETO;
-		return out;
-	}
-
-	return geom;
-}
-
-drawvec fix_polygon(drawvec &geom) {
-	int outer = 1;
-	drawvec out;
-
-	unsigned i;
-	for (i = 0; i < geom.size(); i++) {
-		if (geom[i].op == VT_CLOSEPATH) {
-			outer = 1;
-		} else if (geom[i].op == VT_MOVETO) {
-			// Find the end of the ring
-
-			unsigned j;
-			for (j = i + 1; j < geom.size(); j++) {
-				if (geom[j].op != VT_LINETO) {
-					break;
-				}
-			}
-
-			// Make a temporary copy of the ring.
-			// Close it if it isn't closed.
-
-			drawvec ring;
-			for (unsigned a = i; a < j; a++) {
-				ring.push_back(geom[a]);
-			}
-			if (j - i != 0 && (ring[0].x != ring[j - i - 1].x || ring[0].y != ring[j - i - 1].y)) {
-				ring.push_back(ring[0]);
-			}
-
-			// Reverse ring if winding order doesn't match
-			// inner/outer expectation
-
-			double area = 0;
-			for (unsigned k = 0; k < ring.size(); k++) {
-				area += (long double) ring[k].x * (long double) ring[(k + 1) % ring.size()].y;
-				area -= (long double) ring[k].y * (long double) ring[(k + 1) % ring.size()].x;
-			}
-
-			if ((area > 0) != outer) {
-				drawvec tmp;
-				for (int a = ring.size() - 1; a >= 0; a--) {
-					tmp.push_back(ring[a]);
-				}
-				ring = tmp;
-			}
-
-			// Copy ring into output, fixing the moveto/lineto ops if necessary because of
-			// reversal or closing
-
-			for (unsigned a = 0; a < ring.size(); a++) {
-				if (a == 0) {
-					out.push_back(draw(VT_MOVETO, ring[a].x, ring[a].y));
-				} else {
-					out.push_back(draw(VT_LINETO, ring[a].x, ring[a].y));
-				}
-			}
-
-			// Next ring or polygon begins on the non-lineto that ended this one
-			// and is not an outer ring unless there is a terminator first
-
-			i = j - 1;
-			outer = 0;
-		} else {
-			fprintf(stderr, "Internal error: polygon ring begins with %d, not moveto\n", geom[i].op);
-			exit(EXIT_FAILURE);
-		}
-	}
-
-	return out;
-}

geometry.hh

@@ -1,29 +0,0 @@
-struct draw {
-	signed char op;
-	long long x;
-	long long y;
-	int necessary;
-
-	draw(int op, long long x, long long y) {
-		this->op = op;
-		this->x = x;
-		this->y = y;
-	}
-
-	draw() {
-	}
-};
-
-typedef std::vector<draw> drawvec;
-
-drawvec decode_geometry(char **meta, int z, unsigned tx, unsigned ty, int detail, long long *bbox);
-void to_tile_scale(drawvec &geom, int z, int detail);
-drawvec remove_noop(drawvec geom, int type, int shift);
-drawvec clip_point(drawvec &geom, int z, int detail, long long buffer);
-drawvec clean_or_clip_poly(drawvec &geom, int z, int detail, int buffer, bool clip);
-drawvec reduce_tiny_poly(drawvec &geom, int z, int detail, bool *reduced, double *accum_area);
-drawvec clip_lines(drawvec &geom, int z, int detail, long long buffer);
-int quick_check(long long *bbox, int z, int detail, long long buffer);
-drawvec simplify_lines(drawvec &geom, int z, int detail);
-drawvec reorder_lines(drawvec &geom);
-drawvec fix_polygon(drawvec &geom);

geometry.hpp

@@ -0,0 +1,78 @@
+#ifndef GEOMETRY_HPP
+#define GEOMETRY_HPP
+
+#include <vector>
+#include <sqlite3.h>
+
+#define VT_POINT 1
+#define VT_LINE 2
+#define VT_POLYGON 3
+
+#define VT_END 0
+#define VT_MOVETO 1
+#define VT_LINETO 2
+#define VT_CLOSEPATH 7
+
+// The bitfield is to make sizeof(draw) be 16 instead of 24
+// at the cost, apparently, of a 0.7% increase in running time
+// for packing and unpacking.
+struct draw {
+	long long x : 40;
+	signed char op;
+	long long y : 40;
+	signed char necessary;
+
+	draw(int nop, long long nx, long long ny) {
+		this->op = nop;
+		this->x = nx;
+		this->y = ny;
+		this->necessary = 0;
+	}
+
+	draw() {
+		this->op = 0;
+		this->x = 0;
+		this->y = 0;
+		this->necessary = 0;
+	}
+
+	bool operator<(draw const &s) const {
+		if (y < s.y || (y == s.y && x < s.x)) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	bool operator==(draw const &s) const {
+		return y == s.y && x == s.x;
+	}
+
+	bool operator!=(draw const &s) const {
+		return y != s.y || x != s.x;
+	}
+};
+
+typedef std::vector<draw> drawvec;
+
+drawvec decode_geometry(FILE *meta, long long *geompos, int z, unsigned tx, unsigned ty, long long *bbox, unsigned initial_x, unsigned initial_y);
+void to_tile_scale(drawvec &geom, int z, int detail);
+drawvec remove_noop(drawvec geom, int type, int shift);
+drawvec clip_point(drawvec &geom, int z, long long buffer);
+drawvec clean_or_clip_poly(drawvec &geom, int z, int detail, int buffer, bool clip);
+drawvec simple_clip_poly(drawvec &geom, int z, int buffer);
+drawvec close_poly(drawvec &geom);
+drawvec reduce_tiny_poly(drawvec &geom, int z, int detail, bool *reduced, double *accum_area);
+drawvec clip_lines(drawvec &geom, int z, long long buffer);
+drawvec stairstep(drawvec &geom, int z, int detail);
+bool point_within_tile(long long x, long long y, int z, long long buffer);
+int quick_check(long long *bbox, int z, long long buffer);
+drawvec simplify_lines(drawvec &geom, int z, int detail, bool mark_tile_bounds, double simplification, size_t retain);
+drawvec reorder_lines(drawvec &geom);
+drawvec fix_polygon(drawvec &geom);
+std::vector<drawvec> chop_polygon(std::vector<drawvec> &geoms);
+void check_polygon(drawvec &geom, drawvec &before);
+double get_area(drawvec &geom, size_t i, size_t j);
+double get_mp_area(drawvec &geom);
+
+#endif

jsonpull/jsonpull.c

@@ -1,3 +1,4 @@
+#define _GNU_SOURCE  // for asprintf()
 #include <stdio.h>
 #include <stdlib.h>
 #include <ctype.h>
@@ -7,8 +8,12 @@
 
 #define BUFFER 10000
 
-json_pull *json_begin(int (*read)(struct json_pull *, char *buffer, int n), void *source) {
+json_pull *json_begin(ssize_t (*read)(struct json_pull *, char *buffer, size_t n), void *source) {
 	json_pull *j = malloc(sizeof(json_pull));
+	if (j == NULL) {
+		perror("Out of memory");
+		exit(EXIT_FAILURE);
+	}
 
 	j->error = NULL;
 	j->line = 1;
@@ -17,40 +22,45 @@ json_pull *json_begin(int (*read)(struct json_pull *, char *buffer, int n), void
 
 	j->read = read;
 	j->source = source;
-	j->buffer = malloc(BUFFER);
 	j->buffer_head = 0;
 	j->buffer_tail = 0;
 
+	j->buffer = malloc(BUFFER);
+	if (j->buffer == NULL) {
+		perror("Out of memory");
+		exit(EXIT_FAILURE);
+	}
+
 	return j;
 }
 
 static inline int peek(json_pull *j) {
 	if (j->buffer_head < j->buffer_tail) {
-		return j->buffer[j->buffer_head];
+		return (unsigned char) j->buffer[j->buffer_head];
 	} else {
 		j->buffer_head = 0;
 		j->buffer_tail = j->read(j, j->buffer, BUFFER);
 		if (j->buffer_head >= j->buffer_tail) {
 			return EOF;
 		}
-		return j->buffer[j->buffer_head];
+		return (unsigned char) j->buffer[j->buffer_head];
 	}
 }
 
 static inline int next(json_pull *j) {
 	if (j->buffer_head < j->buffer_tail) {
-		return j->buffer[j->buffer_head++];
+		return (unsigned char) j->buffer[j->buffer_head++];
 	} else {
 		j->buffer_head = 0;
 		j->buffer_tail = j->read(j, j->buffer, BUFFER);
 		if (j->buffer_head >= j->buffer_tail) {
 			return EOF;
 		}
-		return j->buffer[j->buffer_head++];
+		return (unsigned char) j->buffer[j->buffer_head++];
 	}
 }
 
-static int read_file(json_pull *j, char *buffer, int n) {
+static ssize_t read_file(json_pull *j, char *buffer, size_t n) {
 	return fread(buffer, 1, n, j->source);
 }
 
@@ -58,24 +68,25 @@ json_pull *json_begin_file(FILE *f) {
 	return json_begin(read_file, f);
 }
 
-static int read_string(json_pull *j, char *buffer, int n) {
-	char *cp = j->source;
-	int out = 0;
+static ssize_t read_string(json_pull *j, char *buffer, size_t n) {
+	const char *cp = j->source;
+	size_t out = 0;
 
 	while (out < n && cp[out] != '\0') {
 		buffer[out] = cp[out];
 		out++;
 	}
 
-	j->source = cp + out;
+	j->source = (void *) (cp + out);
 	return out;
 }
 
-json_pull *json_begin_string(char *s) {
-	return json_begin(read_string, s);
+json_pull *json_begin_string(const char *s) {
+	return json_begin(read_string, (void *) s);
 }
 
 void json_end(json_pull *p) {
+	json_free(p->root);
 	free(p->buffer);
 	free(p);
 }
@@ -90,28 +101,41 @@ static inline int read_wrap(json_pull *j) {
 	return c;
 }
 
-#define SIZE_FOR(i) (((i) + 31) & ~31)
+#define SIZE_FOR(i, size) ((size_t)((((i) + 31) & ~31) * size))
 
-static json_object *fabricate_object(json_object *parent, json_type type) {
+static json_object *fabricate_object(json_pull *jp, json_object *parent, json_type type) {
 	json_object *o = malloc(sizeof(struct json_object));
+	if (o == NULL) {
+		perror("Out of memory");
+		exit(EXIT_FAILURE);
+	}
 	o->type = type;
 	o->parent = parent;
 	o->array = NULL;
 	o->keys = NULL;
 	o->values = NULL;
 	o->length = 0;
+	o->parser = jp;
 	return o;
 }
 
 static json_object *add_object(json_pull *j, json_type type) {
 	json_object *c = j->container;
-	json_object *o = fabricate_object(c, type);
+	json_object *o = fabricate_object(j, c, type);
 
 	if (c != NULL) {
 		if (c->type == JSON_ARRAY) {
 			if (c->expect == JSON_ITEM) {
-				if (SIZE_FOR(c->length + 1) != SIZE_FOR(c->length)) {
-					c->array = realloc(c->array, SIZE_FOR(c->length + 1) * sizeof(json_object *));
+				if (SIZE_FOR(c->length + 1, sizeof(json_object *)) != SIZE_FOR(c->length, sizeof(json_object *))) {
+					if (SIZE_FOR(c->length + 1, sizeof(json_object *)) < SIZE_FOR(c->length, sizeof(json_object *))) {
+						fprintf(stderr, "Array size overflow\n");
+						exit(EXIT_FAILURE);
+					}
+					c->array = realloc(c->array, SIZE_FOR(c->length + 1, sizeof(json_object *)));
+					if (c->array == NULL) {
+						perror("Out of memory");
+						exit(EXIT_FAILURE);
+					}
 				}
 
 				c->array[c->length++] = o;
@@ -132,9 +156,17 @@ static json_object *add_object(json_pull *j, json_type type) {
 					return NULL;
 				}
 
-				if (SIZE_FOR(c->length + 1) != SIZE_FOR(c->length)) {
-					c->keys = realloc(c->keys, SIZE_FOR(c->length + 1) * sizeof(json_object *));
-					c->values = realloc(c->values, SIZE_FOR(c->length + 1) * sizeof(json_object *));
+				if (SIZE_FOR(c->length + 1, sizeof(json_object *)) != SIZE_FOR(c->length, sizeof(json_object *))) {
+					if (SIZE_FOR(c->length + 1, sizeof(json_object *)) < SIZE_FOR(c->length, sizeof(json_object *))) {
+						fprintf(stderr, "Hash size overflow\n");
+						exit(EXIT_FAILURE);
+					}
+					c->keys = realloc(c->keys, SIZE_FOR(c->length + 1, sizeof(json_object *)));
+					c->values = realloc(c->values, SIZE_FOR(c->length + 1, sizeof(json_object *)));
+					if (c->keys == NULL || c->values == NULL) {
+						perror("Out of memory");
+						exit(EXIT_FAILURE);
+					}
 				}
 
 				c->keys[c->length] = o;
@@ -148,6 +180,10 @@ static json_object *add_object(json_pull *j, json_type type) {
 			}
 		}
 	} else {
+		if (j->root != NULL) {
+			json_free(j->root);
+		}
+
 		j->root = o;
 	}
 
@@ -159,7 +195,7 @@ json_object *json_hash_get(json_object *o, const char *s) {
 		return NULL;
 	}
 
-	int i;
+	size_t i;
 	for (i = 0; i < o->length; i++) {
 		if (o->keys[i] != NULL && o->keys[i]->type == JSON_STRING) {
 			if (strcmp(o->keys[i]->string, s) == 0) {
@@ -173,27 +209,64 @@ json_object *json_hash_get(json_object *o, const char *s) {
 
 struct string {
 	char *buf;
-	int n;
-	int nalloc;
+	size_t n;
+	size_t nalloc;
 };
 
 static void string_init(struct string *s) {
 	s->nalloc = 500;
 	s->buf = malloc(s->nalloc);
+	if (s->buf == NULL) {
+		perror("Out of memory");
+		exit(EXIT_FAILURE);
+	}
 	s->n = 0;
 	s->buf[0] = '\0';
 }
 
 static void string_append(struct string *s, char c) {
 	if (s->n + 2 >= s->nalloc) {
+		size_t prev = s->nalloc;
 		s->nalloc += 500;
+		if (s->nalloc <= prev) {
+			fprintf(stderr, "String size overflowed\n");
+			exit(EXIT_FAILURE);
+		}
 		s->buf = realloc(s->buf, s->nalloc);
+		if (s->buf == NULL) {
+			perror("Out of memory");
+			exit(EXIT_FAILURE);
+		}
 	}
 
 	s->buf[s->n++] = c;
 	s->buf[s->n] = '\0';
 }
 
+static void string_append_string(struct string *s, char *add) {
+	size_t len = strlen(add);
+
+	if (s->n + len + 1 >= s->nalloc) {
+		size_t prev = s->nalloc;
+		s->nalloc += 500 + len;
+		if (s->nalloc <= prev) {
+			fprintf(stderr, "String size overflowed\n");
+			exit(EXIT_FAILURE);
+		}
+		s->buf = realloc(s->buf, s->nalloc);
+		if (s->buf == NULL) {
+			perror("Out of memory");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	for (; *add != '\0'; add++) {
+		s->buf[s->n++] = *add;
+	}
+
+	s->buf[s->n] = '\0';
+}
+
 static void string_free(struct string *s) {
 	free(s->buf);
 }
@@ -203,6 +276,10 @@ json_object *json_read_separators(json_pull *j, json_separator_callback cb, void
 
 	// In case there is an error at the top level
 	if (j->container == NULL) {
+		if (j->root != NULL) {
+			json_free(j->root);
+		}
+
 		j->root = NULL;
 	}
 
@@ -218,7 +295,23 @@ again:
 
 			return NULL;
 		}
-	} while (c == ' ' || c == '\t' || c == '\r' || c == '\n');
+
+		// Byte-order mark
+		if (c == 0xEF) {
+			int c2 = peek(j);
+			if (c2 == 0xBB) {
+				c2 = read_wrap(j);
+				c2 = peek(j);
+				if (c2 == 0xBF) {
+					c2 = read_wrap(j);
+					c = ' ';
+					continue;
+				}
+			}
+			j->error = "Corrupt byte-order mark found";
+			return NULL;
+		}
+	} while (c == ' ' || c == '\t' || c == '\r' || c == '\n' || c == 0x1E);
 
 	/////////////////////////// Arrays
 
@@ -307,6 +400,32 @@ again:
 		return add_object(j, JSON_NULL);
 	}
 
+	/////////////////////////// NaN
+
+	if (c == 'N') {
+		if (read_wrap(j) != 'a' || read_wrap(j) != 'N') {
+			j->error = "Found misspelling of NaN";
+			return NULL;
+		}
+
+		j->error = "JSON does not allow NaN";
+		return NULL;
+	}
+
+	/////////////////////////// Infinity
+
+	if (c == 'I') {
+		if (read_wrap(j) != 'n' || read_wrap(j) != 'f' || read_wrap(j) != 'i' ||
+		    read_wrap(j) != 'n' || read_wrap(j) != 'i' || read_wrap(j) != 't' ||
+		    read_wrap(j) != 'y') {
+			j->error = "Found misspelling of Infinity";
+			return NULL;
+		}
+
+		j->error = "JSON does not allow Infinity";
+		return NULL;
+	}
+
 	/////////////////////////// True
 
 	if (c == 't') {
@@ -401,6 +520,11 @@ again:
 			string_append(&val, read_wrap(j));
 
 			c = peek(j);
+			if (c < '0' || c > '9') {
+				j->error = "Decimal point without digits";
+				string_free(&val);
+				return NULL;
+			}
 			while (c >= '0' && c <= '9') {
 				string_append(&val, read_wrap(j));
 				c = peek(j);
@@ -472,6 +596,11 @@ again:
 					int i;
 					for (i = 0; i < 4; i++) {
 						hex[i] = read_wrap(j);
+						if (hex[i] < '0' || (hex[i] > '9' && hex[i] < 'A') || (hex[i] > 'F' && hex[i] < 'a') || hex[i] > 'f') {
+							j->error = "Invalid \\u hex character";
+							string_free(&val);
+							return NULL;
+						}
 					}
 					unsigned long ch = strtoul(hex, NULL, 16);
 					if (ch <= 0x7F) {
@@ -489,10 +618,19 @@ again:
 					string_free(&val);
 					return NULL;
 				}
+			} else if (c < ' ') {
+				j->error = "Found control character in string";
+				string_free(&val);
+				return NULL;
 			} else {
 				string_append(&val, c);
 			}
 		}
+		if (c == EOF) {
+			j->error = "String without closing quote mark";
+			string_free(&val);
+			return NULL;
+		}
 
 		json_object *s = add_object(j, JSON_STRING);
 		if (s != NULL) {
@@ -525,7 +663,7 @@ json_object *json_read_tree(json_pull *p) {
 }
 
 void json_free(json_object *o) {
-	int i;
+	size_t i;
 
 	if (o == NULL) {
 		return;
@@ -535,7 +673,7 @@ void json_free(json_object *o) {
 
 	if (o->type == JSON_ARRAY) {
 		json_object **a = o->array;
-		int n = o->length;
+		size_t n = o->length;
 
 		o->array = NULL;
 		o->length = 0;
@@ -548,7 +686,7 @@ void json_free(json_object *o) {
 	} else if (o->type == JSON_HASH) {
 		json_object **k = o->keys;
 		json_object **v = o->values;
-		int n = o->length;
+		size_t n = o->length;
 
 		o->keys = NULL;
 		o->values = NULL;
@@ -570,13 +708,30 @@ void json_free(json_object *o) {
 	free(o);
 }
 
+static void json_disconnect_parser(json_object *o) {
+	if (o->type == JSON_HASH) {
+		size_t i;
+		for (i = 0; i < o->length; i++) {
+			json_disconnect_parser(o->keys[i]);
+			json_disconnect_parser(o->values[i]);
+		}
+	} else if (o->type == JSON_ARRAY) {
+		size_t i;
+		for (i = 0; i < o->length; i++) {
+			json_disconnect_parser(o->array[i]);
+		}
+	}
+
+	o->parser = NULL;
+}
+
 void json_disconnect(json_object *o) {
 	// Expunge references to this as an array element
 	// or a hash key or value.
 
 	if (o->parent != NULL) {
 		if (o->parent->type == JSON_ARRAY) {
-			int i;
+			size_t i;
 
 			for (i = 0; i < o->parent->length; i++) {
 				if (o->parent->array[i] == o) {
@@ -591,15 +746,15 @@ void json_disconnect(json_object *o) {
 		}
 
 		if (o->parent->type == JSON_HASH) {
-			int i;
+			size_t i;
 
 			for (i = 0; i < o->parent->length; i++) {
 				if (o->parent->keys[i] == o) {
-					o->parent->keys[i] = fabricate_object(o->parent, JSON_NULL);
+					o->parent->keys[i] = fabricate_object(o->parser, o->parent, JSON_NULL);
 					break;
 				}
 				if (o->parent->values[i] == o) {
-					o->parent->values[i] = fabricate_object(o->parent, JSON_NULL);
+					o->parent->values[i] = fabricate_object(o->parser, o->parent, JSON_NULL);
 					break;
 				}
 			}
@@ -619,5 +774,88 @@ void json_disconnect(json_object *o) {
 		}
 	}
 
+	if (o->parser != NULL && o->parser->root == o) {
+		o->parser->root = NULL;
+	}
+
+	json_disconnect_parser(o);
 	o->parent = NULL;
 }
+
+static void json_print_one(struct string *val, json_object *o) {
+	if (o == NULL) {
+		string_append_string(val, "...");
+	} else if (o->type == JSON_STRING) {
+		string_append(val, '\"');
+
+		char *cp;
+		for (cp = o->string; *cp != '\0'; cp++) {
+			if (*cp == '\\' || *cp == '"') {
+				string_append(val, '\\');
+				string_append(val, *cp);
+			} else if (*cp >= 0 && *cp < ' ') {
+				char *s;
+				if (asprintf(&s, "\\u%04x", *cp) >= 0) {
+					string_append_string(val, s);
+					free(s);
+				}
+			} else {
+				string_append(val, *cp);
+			}
+		}
+
+		string_append(val, '\"');
+	} else if (o->type == JSON_NUMBER) {
+		string_append_string(val, o->string);
+	} else if (o->type == JSON_NULL) {
+		string_append_string(val, "null");
+	} else if (o->type == JSON_TRUE) {
+		string_append_string(val, "true");
+	} else if (o->type == JSON_FALSE) {
+		string_append_string(val, "false");
+	} else if (o->type == JSON_HASH) {
+		string_append(val, '}');
+	} else if (o->type == JSON_ARRAY) {
+		string_append(val, ']');
+	}
+}
+
+static void json_print(struct string *val, json_object *o) {
+	if (o == NULL) {
+		// Hash value in incompletely read hash
+		string_append_string(val, "...");
+	} else if (o->type == JSON_HASH) {
+		string_append(val, '{');
+
+		size_t i;
+		for (i = 0; i < o->length; i++) {
+			json_print(val, o->keys[i]);
+			string_append(val, ':');
+			json_print(val, o->values[i]);
+			if (i + 1 < o->length) {
+				string_append(val, ',');
+			}
+		}
+		string_append(val, '}');
+	} else if (o->type == JSON_ARRAY) {
+		string_append(val, '[');
+		size_t i;
+		for (i = 0; i < o->length; i++) {
+			json_print(val, o->array[i]);
+			if (i + 1 < o->length) {
+				string_append(val, ',');
+			}
+		}
+		string_append(val, ']');
+	} else {
+		json_print_one(val, o);
+	}
+}
+
+char *json_stringify(json_object *o) {
+	struct string val;
+	string_init(&val);
+	json_print(&val, o);
+
+	return val.buf;
+}

jsonpull/jsonpull.h

@@ -1,3 +1,10 @@
+#ifndef JSONPULL_H
+#define JSONPULL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef enum json_type {
 	// These types can be returned by json_read()
 	JSON_HASH,
@@ -21,6 +28,7 @@ typedef enum json_type {
 typedef struct json_object {
 	json_type type;
 	struct json_object *parent;
+	struct json_pull *parser;
 
 	char *string;
 	double number;
@@ -28,7 +36,7 @@ typedef struct json_object {
 	struct json_object **array;
 	struct json_object **keys;
 	struct json_object **values;
-	int length;
+	size_t length;
 
 	int expect;
 } json_object;
@@ -37,20 +45,20 @@ typedef struct json_pull {
 	char *error;
 	int line;
 
-	int (*read)(struct json_pull *, char *buf, int n);
+	ssize_t (*read)(struct json_pull *, char *buf, size_t n);
 	void *source;
 	char *buffer;
-	int buffer_tail;
-	int buffer_head;
+	ssize_t buffer_tail;
+	ssize_t buffer_head;
 
 	json_object *container;
 	json_object *root;
 } json_pull;
 
 json_pull *json_begin_file(FILE *f);
-json_pull *json_begin_string(char *s);
+json_pull *json_begin_string(const char *s);
 
-json_pull *json_begin(int (*read)(struct json_pull *, char *buffer, int n), void *source);
+json_pull *json_begin(ssize_t (*read)(struct json_pull *, char *buffer, size_t n), void *source);
 void json_end(json_pull *p);
 
 typedef void (*json_separator_callback)(json_type type, json_pull *j, void *state);
@@ -62,3 +70,11 @@ void json_free(json_object *j);
 void json_disconnect(json_object *j);
 
 json_object *json_hash_get(json_object *o, const char *s);
+
+char *json_stringify(json_object *o);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

main.hpp

@@ -0,0 +1,30 @@
+#ifndef MAIN_HPP
+#define MAIN_HPP
+
+#include <stddef.h>
+
+struct index {
+	long long start;
+	long long end;
+	unsigned long long index;
+	short segment;
+	unsigned short t : 2;
+	unsigned long long seq : (64 - 18);  // pack with segment and t to stay in 32 bytes
+};
+
+void checkdisk(struct reader *r, int nreader);
+
+extern int geometry_scale;
+extern int quiet;
+
+extern size_t CPUS;
+extern size_t TEMP_FILES;
+
+extern size_t max_tile_size;
+
+int mkstemp_cloexec(char *name);
+FILE *fopen_oflag(const char *name, const char *mode, int oflag);
+
+#define MAX_ZOOM 24
+
+#endif

man/tippecanoe.1

@@ -1,10 +1,10 @@
 .TH tippecanoe
 .PP
-Builds vector tilesets
-\[la]https://www.mapbox.com/developers/vector-tiles/\[ra] from large collections of GeoJSON
-\[la]http://geojson.org/\[ra]
-features. This is a tool for making maps from huge datasets
-\[la]MADE_WITH.md\[ra]\&.
+Builds vector tilesets \[la]https://www.mapbox.com/developers/vector-tiles/\[ra] from large (or small) collections of GeoJSON \[la]http://geojson.org/\[ra] or Geobuf \[la]https://github.com/mapbox/geobuf\[ra] features,
+like these \[la]MADE_WITH.md\[ra]\&.
+.PP
+[Build Status](https://travis\-ci.org/mapbox/tippecanoe.svg) \[la]https://travis-ci.org/mapbox/tippecanoe\[ra]
+[Coverage Status](https://coveralls.io/repos/mapbox/tippecanoe/badge.svg?branch=master&service=github) \[la]https://coveralls.io/github/mapbox/tippecanoe?branch=master\[ra]
 .SH Intent
 .PP
 The goal of Tippecanoe is to enable making a scale\-independent view of your data,
@@ -13,8 +13,7 @@ the density and texture of the data rather than a simplification from dropping
 supposedly unimportant features or clustering or aggregating them.
 .PP
 If you give it all of OpenStreetMap and zoom out, it should give you back
-something that looks like "All Streets
-\[la]http://benfry.com/allstreets/map5.html\[ra]"
+something that looks like "All Streets \[la]http://benfry.com/allstreets/map5.html\[ra]"
 rather than something that looks like an Interstate road atlas.
 .PP
 If you give it all the building footprints in Los Angeles and zoom out
@@ -27,8 +26,7 @@ see the shape and relative popularity of every point of interest and every
 significant travel corridor.
 .SH Installation
 .PP
-The easiest way to install tippecanoe on OSX is with Homebrew
-\[la]http://brew.sh/\[ra]:
+The easiest way to install tippecanoe on OSX is with Homebrew \[la]http://brew.sh/\[ra]:
 .PP
 .RS
 .nf
@@ -39,7 +37,7 @@ $ brew install tippecanoe
 .PP
 .RS
 .nf
-$ tippecanoe \-o file.mbtiles [file.json ...]
+$ tippecanoe \-o file.mbtiles [options] [file.json file.geobuf ...]
 .fi
 .RE
 .PP
@@ -50,81 +48,27 @@ The GeoJSON features need not be wrapped in a FeatureCollection.
 You can concatenate multiple GeoJSON features or files together,
 and it will parse out the features and ignore whatever other objects
 it encounters.
-.SH Options
-.SS Naming
+.SH Try this first
+.PP
+If you aren't sure what options to use, try this:
+.PP
 .RS
-.IP \(bu 2
-\-l \fIname\fP: Layer name (default "file" if source is file.json or output is file.mbtiles). Only works if there is only one layer.
-.IP \(bu 2
-\-n \fIname\fP: Human\-readable name (default file.json)
+.nf
+$ tippecanoe \-o out.mbtiles \-zg \-\-drop\-densest\-as\-needed in.geojson
+.fi
 .RE
-.SS File control
-.RS
-.IP \(bu 2
-\-o \fIfile\fP\&.mbtiles: Name the output file.
-.IP \(bu 2
-\-f: Delete the mbtiles file if it already exists instead of giving an error
-.IP \(bu 2
-\-t \fIdirectory\fP: Put the temporary files in \fIdirectory\fP\&.
-.RE
-.SS Zoom levels and resolution
-.RS
-.IP \(bu 2
-\-z \fIzoom\fP: Base (maxzoom) zoom level (default 14)
-.IP \(bu 2
-\-Z \fIzoom\fP: Lowest (minzoom) zoom level (default 0)
-.IP \(bu 2
-\-d \fIdetail\fP: Detail at base zoom level (default 12 at \-z14 or higher, or 13 at \-z13 or lower. Detail beyond 13 has rendering problems with Mapbox GL.)
-.IP \(bu 2
-\-D \fIdetail\fP: Detail at lower zoom levels (default 10, for tile resolution of 1024)
-.IP \(bu 2
-\-m \fIdetail\fP: Minimum detail that it will try if tiles are too big at regular detail (default 7)
-.IP \(bu 2
-\-b \fIpixels\fP: Buffer size where features are duplicated from adjacent tiles. Units are "screen pixels"\-\-1/256th of the tile width or height. (default 5)
-.RE
-.SS Properties
-.RS
-.IP \(bu 2
-\-x \fIname\fP: Exclude the named properties from all features
-.IP \(bu 2
-\-y \fIname\fP: Include the named properties in all features, excluding all those not explicitly named
-.IP \(bu 2
-\-X: Exclude all properties and encode only geometries
-.RE
-.SS Point simplification
-.RS
-.IP \(bu 2
-\-r \fIrate\fP: Rate at which dots are dropped at lower zoom levels (default 2.5)
-.IP \(bu 2
-\-g \fIgamma\fP: Rate at which especially dense dots are dropped (default 0, for no effect). A gamma of 2 reduces the number of dots less than a pixel apart to the square root of their original number.
-.RE
-.SS Doing more
-.RS
-.IP \(bu 2
-\-ac: Coalesce adjacent line and polygon features that have the same properties
-.IP \(bu 2
-\-ar: Try reversing the directions of lines to make them coalesce and compress better
-.IP \(bu 2
-\-ao: Reorder features to put ones with the same properties in sequence, to try to get them to coalesce
-.IP \(bu 2
-\-al: Let "dot" dropping at lower zooms apply to lines too
-.RE
-.SS Doing less
-.RS
-.IP \(bu 2
-\-ps: Don't simplify lines
-.IP \(bu 2
-\-pf: Don't limit tiles to 200,000 features
-.IP \(bu 2
-\-pk: Don't limit tiles to 500K bytes
-.IP \(bu 2
-\-pd: Dynamically drop some fraction of features from large tiles to keep them under the 500K size limit. It will probably look ugly at the tile boundaries.
-.IP \(bu 2
-\-pi: Preserve the original input order of features as the drawing order instead of ordering geographically. (This is implemented as a restoration of the original order at the end, so that dot\-dropping is still geographic, which means it also undoes \-ao).
-.IP \(bu 2
-\-q: Work quietly instead of reporting progress
-.RE
-.SH Example
+.PP
+The \fB\fC\-zg\fR option will make Tippecanoe choose a maximum zoom level that should be
+high enough to reflect the precision of the original data. (If it turns out still
+not to be as detailed as you want, use \fB\fC\-z\fR manually with a higher number.)
+.PP
+If the tiles come out too big, the \fB\fC\-\-drop\-densest\-as\-needed\fR option will make
+Tippecanoe try dropping what should be the least visible features at each zoom level.
+(If it drops too many features, use \fB\fC\-x\fR to leave out some feature attributes that
+you didn't really need.)
+.SH Examples
+.PP
+Create a tileset of TIGER roads for Alameda County, to zoom level 13, with a custom layer name and description:
 .PP
 .RS
 .nf
@@ -132,15 +76,319 @@ $ tippecanoe \-o alameda.mbtiles \-l alameda \-n "Alameda County from TIGER" \-z
 .fi
 .RE
 .PP
+Create a tileset of all TIGER roads, at only zoom level 12, but with higher detail than normal,
+with a custom layer name and description, and leaving out the \fB\fCLINEARID\fR and \fB\fCRTTYP\fR attributes:
+.PP
 .RS
 .nf
 $ cat tiger/tl_2014_*_roads.json | tippecanoe \-o tiger.mbtiles \-l roads \-n "All TIGER roads, one zoom" \-z12 \-Z12 \-d14 \-x LINEARID \-x RTTYP
 .fi
 .RE
+.SH Options
+.PP
+There are a lot of options. A lot of the time you won't want to use any of them
+other than \fB\fC\-o\fR \fIoutput\fP\fB\fC\&.mbtiles\fR to name the output file, and probably \fB\fC\-f\fR to
+delete the file that already exists with that name.
+.PP
+If you aren't sure what the right maxzoom is for your data, \fB\fC\-zg\fR will guess one for you
+based on the density of features.
+.PP
+If you are mapping point features, you will often want to use \fB\fC\-Bg\fR to automatically choose
+a base zoom level for dot dropping. If that doesn't work out for you, try
+\fB\fC\-r1 \-\-drop\-fraction\-as\-needed\fR to turn off the normal dot dropping and instead
+only drop features if the tiles get too big.
+.PP
+If you are mapping points or polygons, you will often want to use \fB\fC\-\-drop\-densest\-as\-needed\fR
+to drop some of them if necessary to make the low zoom levels work.
+.PP
+If your features have a lot of attributes, use \fB\fC\-y\fR to keep only the ones you really need.
+.PP
+If your input is formatted as newline\-delimited GeoJSON, use \fB\fC\-P\fR to make input parsing a lot faster.
+.SS Output tileset
+.RS
+.IP \(bu 2
+\fB\fC\-o\fR \fIfile\fP\fB\fC\&.mbtiles\fR or \fB\fC\-\-output=\fR\fIfile\fP\fB\fC\&.mbtiles\fR: Name the output file.
+.IP \(bu 2
+\fB\fC\-e\fR \fIdirectory\fP or \fB\fC\-\-output\-to\-directory\fR=\fIdirectory\fP: Write tiles to the specified \fIdirectory\fP instead of to an mbtiles file.
+.IP \(bu 2
+\fB\fC\-f\fR or \fB\fC\-\-force\fR: Delete the mbtiles file if it already exists instead of giving an error
+.IP \(bu 2
+\fB\fC\-F\fR or \fB\fC\-\-allow\-existing\fR: Proceed (without deleting existing data) if the metadata or tiles table already exists
+or if metadata fields can't be set. You probably don't want to use this.
+.RE
+.SS Tileset description and attribution
+.RS
+.IP \(bu 2
+\fB\fC\-n\fR \fIname\fP or \fB\fC\-\-name=\fR\fIname\fP: Human\-readable name for the tileset (default file.json)
+.IP \(bu 2
+\fB\fC\-A\fR \fItext\fP or \fB\fC\-\-attribution=\fR\fItext\fP: Attribution (HTML) to be shown with maps that use data from this tileset.
+.IP \(bu 2
+\fB\fC\-N\fR \fIdescription\fP or \fB\fC\-\-description=\fR\fIdescription\fP: Description for the tileset (default file.mbtiles)
+.RE
+.SS Input files and layer names
+.RS
+.IP \(bu 2
+\fIname\fP\fB\fC\&.json\fR or \fIname\fP\fB\fC\&.geojson\fR: Read the named GeoJSON input file into a layer called \fIname\fP\&.
+.IP \(bu 2
+\fIname\fP\fB\fC\&.geobuf\fR or \fIname\fP\fB\fC\&.geobuf\fR: Read the named Geobuf input file into a layer called \fIname\fP\&.
+.IP \(bu 2
+\fB\fC\-l\fR \fIname\fP or \fB\fC\-\-layer=\fR\fIname\fP: Use the specified layer name instead of deriving a name from the input filename or output tileset. If there are multiple input files
+specified, the files are all merged into the single named layer, even if they try to specify individual names with \fB\fC\-L\fR\&.
+.IP \(bu 2
+\fB\fC\-L\fR \fIname\fP\fB\fC:\fR\fIfile.json\fP or \fB\fC\-\-named\-layer=\fR\fIname\fP\fB\fC:\fR\fIfile.json\fP: Specify layer names for individual files. If your shell supports it, you can use a subshell redirect like \fB\fC\-L\fR \fIname\fP\fB\fC:<(cat dir/*.json)\fR to specify a layer name for the output of streamed input.
+.RE
+.SS Parallel processing of input
+.RS
+.IP \(bu 2
+\fB\fC\-P\fR or \fB\fC\-\-read\-parallel\fR: Use multiple threads to read different parts of each GeoJSON input file at once.
+This will only work if the input is line\-delimited JSON with each Feature on its
+own line, because it knows nothing of the top\-level structure around the Features. Spurious "EOF" error
+messages may result otherwise.
+Performance will be better if the input is a named file that can be mapped into memory
+rather than a stream that can only be read sequentially.
+.RE
+.PP
+If the input file begins with the RFC 8142 \[la]https://tools.ietf.org/html/rfc8142\[ra] record separator,
+parallel processing of input will be invoked automatically, splitting at record separators rather
+than at all newlines.
+.PP
+Parallel processing will also be automatic if the input file is in Geobuf format.
+.SS Projection of input
+.RS
+.IP \(bu 2
+\fB\fC\-s\fR \fIprojection\fP or \fB\fC\-\-projection=\fR\fIprojection\fP: Specify the projection of the input data. Currently supported are \fB\fCEPSG:4326\fR (WGS84, the default) and \fB\fCEPSG:3857\fR (Web Mercator). In general you should use WGS84 for your input files if at all possible.
+.RE
+.SS Zoom levels
+.RS
+.IP \(bu 2
+\fB\fC\-z\fR \fIzoom\fP or \fB\fC\-\-maximum\-zoom=\fR\fIzoom\fP: Maxzoom: the highest zoom level for which tiles are generated (default 14)
+.IP \(bu 2
+\fB\fC\-zg\fR or \fB\fC\-\-maximum\-zoom=g\fR: Guess what is probably a reasonable maxzoom based on the spacing of features.
+.IP \(bu 2
+\fB\fC\-Z\fR \fIzoom\fP or \fB\fC\-\-minimum\-zoom=\fR\fIzoom\fP: Minzoom: the lowest zoom level for which tiles are generated (default 0)
+.IP \(bu 2
+\fB\fC\-ae\fR or \fB\fC\-\-extend\-zooms\-if\-still\-dropping\fR: Increase the maxzoom if features are still being dropped at that zoom level.
+The detail and simplification options that ordinarily apply only to the maximum zoom level will apply both to the originally
+specified maximum zoom and to any levels added beyond that.
+.RE
+.SS Tile resolution
+.RS
+.IP \(bu 2
+\fB\fC\-d\fR \fIdetail\fP or \fB\fC\-\-full\-detail=\fR\fIdetail\fP: Detail at max zoom level (default 12, for tile resolution of 2
+.IP \(bu 2
+\fB\fC\-D\fR \fIdetail\fP or \fB\fC\-\-low\-detail=\fR\fIdetail\fP: Detail at lower zoom levels (default 12, for tile resolution of 2
+.IP \(bu 2
+\fB\fC\-m\fR \fIdetail\fP or \fB\fC\-\-minimum\-detail=\fR\fIdetail\fP: Minimum detail that it will try if tiles are too big at regular detail (default 7)
+.RE
+.PP
+All internal math is done in terms of a 32\-bit tile coordinate system, so 1/(2 of the size of Earth,
+or about 1cm, is the smallest distinguishable distance. If \fImaxzoom\fP + \fIdetail\fP > 32, no additional
+resolution is obtained than by using a smaller \fImaxzoom\fP or \fIdetail\fP\&.
+.SS Filtering feature attributes
+.RS
+.IP \(bu 2
+\fB\fC\-x\fR \fIname\fP or \fB\fC\-\-exclude=\fR\fIname\fP: Exclude the named properties from all features
+.IP \(bu 2
+\fB\fC\-y\fR \fIname\fP or \fB\fC\-\-include=\fR\fIname\fP: Include the named properties in all features, excluding all those not explicitly named
+.IP \(bu 2
+\fB\fC\-X\fR or \fB\fC\-\-exclude\-all\fR: Exclude all properties and encode only geometries
+.IP \(bu 2
+\fB\fC\-T\fR\fIattribute\fP\fB\fC:\fR\fItype\fP or \fB\fC\-\-attribute\-type=\fR\fIattribute\fP\fB\fC:\fR\fItype\fP: Coerce the named feature \fIattribute\fP to be of the specified \fItype\fP\&.
+The \fItype\fP may be \fB\fCstring\fR, \fB\fCfloat\fR, \fB\fCint\fR, or \fB\fCbool\fR\&.
+If the type is \fB\fCbool\fR, then original attributes of \fB\fC0\fR (or, if numeric, \fB\fC0.0\fR, etc.), \fB\fCfalse\fR, \fB\fCnull\fR, or the empty string become \fB\fCfalse\fR, and otherwise become \fB\fCtrue\fR\&.
+If the type is \fB\fCfloat\fR or \fB\fCint\fR and the original attribute was non\-numeric, it becomes \fB\fC0\fR\&.
+If the type is \fB\fCint\fR and the original attribute was floating\-point, it is rounded to the nearest integer.
+.IP \(bu 2
+\fB\fC\-j\fR \fIfilter\fP or \fB\fC\-\-feature\-filter\fR=\fIfilter\fP: Check features against a per\-layer filter (as defined in the Mapbox GL Style Specification \[la]https://www.mapbox.com/mapbox-gl-js/style-spec/#types-filter\[ra]) and only include those that match. Any features in layers that have no filter specified will be passed through. Filters for the layer \fB\fC"*"\fR apply to all layers.
+.IP \(bu 2
+\fB\fC\-J\fR \fIfilter\-file\fP or \fB\fC\-\-feature\-filter\-file\fR=\fIfilter\-file\fP: Like \fB\fC\-j\fR, but read the filter from a file.
+.RE
+.PP
+Example: to find the Natural Earth countries with low \fB\fCscalerank\fR but high \fB\fCLABELRANK\fR:
+.PP
+.RS
+.nf
+tippecanoe \-z5 \-o filtered.mbtiles \-j '{ "ne_10m_admin_0_countries": [ "all", [ "<", "scalerank", 3 ], [ ">", "LABELRANK", 5 ] ] }' ne_10m_admin_0_countries.geojson
+.fi
+.RE
+.SS Dropping a fixed fraction of features by zoom level
+.RS
+.IP \(bu 2
+\fB\fC\-r\fR \fIrate\fP or \fB\fC\-\-drop\-rate=\fR\fIrate\fP: Rate at which dots are dropped at zoom levels below basezoom (default 2.5).
+If you use \fB\fC\-rg\fR, it will guess a drop rate that will keep at most 50,000 features in the densest tile.
+You can also specify a marker\-width with \fB\fC\-rg\fR\fIwidth\fP to allow fewer features in the densest tile to
+compensate for the larger marker, or \fB\fC\-rf\fR\fInumber\fP to allow at most \fInumber\fP features in the densest tile.
+.IP \(bu 2
+\fB\fC\-B\fR \fIzoom\fP or \fB\fC\-\-base\-zoom=\fR\fIzoom\fP: Base zoom, the level at and above which all points are included in the tiles (default maxzoom).
+If you use \fB\fC\-Bg\fR, it will guess a zoom level that will keep at most 50,000 features in the densest tile.
+You can also specify a marker\-width with \fB\fC\-Bg\fR\fIwidth\fP to allow fewer features in the densest tile to
+compensate for the larger marker, or \fB\fC\-Bf\fR\fInumber\fP to allow at most \fInumber\fP features in the densest tile.
+.IP \(bu 2
+\fB\fC\-al\fR or \fB\fC\-\-drop\-lines\fR: Let "dot" dropping at lower zooms apply to lines too
+.IP \(bu 2
+\fB\fC\-ap\fR or \fB\fC\-\-drop\-polygons\fR: Let "dot" dropping at lower zooms apply to polygons too
+.RE
+.SS Dropping a fraction of features to keep under tile size limits
+.RS
+.IP \(bu 2
+\fB\fC\-as\fR or \fB\fC\-\-drop\-densest\-as\-needed\fR: If a tile is too large, try to reduce it to under 500K by increasing the minimum spacing between features. The discovered spacing applies to the entire zoom level.
+.IP \(bu 2
+\fB\fC\-ad\fR or \fB\fC\-\-drop\-fraction\-as\-needed\fR: Dynamically drop some fraction of features from each zoom level to keep large tiles under the 500K size limit. (This is like \fB\fC\-pd\fR but applies to the entire zoom level, not to each tile.)
+.IP \(bu 2
+\fB\fC\-an\fR or \fB\fC\-\-drop\-smallest\-as\-needed\fR: Dynamically drop the smallest features (physically smallest: the shortest lines or the smallest polygons) from each zoom level to keep large tiles under the 500K size limit. This option will not work for point features.
+.IP \(bu 2
+\fB\fC\-aN\fR or \fB\fC\-\-coalesce\-smallest\-as\-needed\fR: Dynamically combine the smallest features (physically smallest: the shortest lines or the smallest polygons) from each zoom level into other nearby features to keep large tiles under the 500K size limit. This option will not work for point features, and will probably not help very much with LineStrings. It is mostly intended for polygons, to maintain the full original area covered by polygons while still reducing the feature count somehow. The attributes of the small polygons are \fInot\fP preserved into the combined features, only their geometry.
+.IP \(bu 2
+\fB\fC\-pd\fR or \fB\fC\-\-force\-feature\-limit\fR: Dynamically drop some fraction of features from large tiles to keep them under the 500K size limit. It will probably look ugly at the tile boundaries. (This is like \fB\fC\-ad\fR but applies to each tile individually, not to the entire zoom level.) You probably don't want to use this.
+.RE
+.SS Dropping tightly overlapping features
+.RS
+.IP \(bu 2
+\fB\fC\-g\fR \fIgamma\fP or \fB\fC\-\-gamma=_gamma\fR_: Rate at which especially dense dots are dropped (default 0, for no effect). A gamma of 2 reduces the number of dots less than a pixel apart to the square root of their original number.
+.IP \(bu 2
+\fB\fC\-aG\fR or \fB\fC\-\-increase\-gamma\-as\-needed\fR: If a tile is too large, try to reduce it to under 500K by increasing the \fB\fC\-g\fR gamma. The discovered gamma applies to the entire zoom level. You probably want to use \fB\fC\-\-drop\-densest\-as\-needed\fR instead.
+.RE
+.SS Line and polygon simplification
+.RS
+.IP \(bu 2
+\fB\fC\-S\fR \fIscale\fP or \fB\fC\-\-simplification=\fR\fIscale\fP: Multiply the tolerance for line and polygon simplification by \fIscale\fP\&. The standard tolerance tries to keep
+the line or polygon within one tile unit of its proper location. You can probably go up to about 10 without too much visible difference.
+.IP \(bu 2
+\fB\fC\-ps\fR or \fB\fC\-\-no\-line\-simplification\fR: Don't simplify lines and polygons
+.IP \(bu 2
+\fB\fC\-pS\fR or \fB\fC\-\-simplify\-only\-low\-zooms\fR: Don't simplify lines and polygons at maxzoom (but do simplify at lower zooms)
+.IP \(bu 2
+\fB\fC\-pt\fR or \fB\fC\-\-no\-tiny\-polygon\-reduction\fR: Don't combine the area of very small polygons into small squares that represent their combined area.
+.RE
+.SS Attempts to improve shared polygon boundaries
+.RS
+.IP \(bu 2
+\fB\fC\-ab\fR or \fB\fC\-\-detect\-shared\-borders\fR: In the manner of TopoJSON \[la]https://github.com/mbostock/topojson/wiki/Introduction\[ra], detect borders that are shared between multiple polygons and simplify them identically in each polygon. This takes more time and memory than considering each polygon individually.
+.IP \(bu 2
+\fB\fC\-aL\fR or \fB\fC\-\-grid\-low\-zooms\fR: At all zoom levels below \fImaxzoom\fP, snap all lines and polygons to a stairstep grid instead of allowing diagonals. You will also want to specify a tile resolution, probably \fB\fC\-D8\fR\&. This option provides a way to display continuous parcel, gridded, or binned data at low zooms without overwhelming the tiles with tiny polygons, since features will either get stretched out to the grid unit or lost entirely, depending on how they happened to be aligned in the original data. You probably don't want to use this.
+.RE
+.SS Controlling clipping to tile boundaries
+.RS
+.IP \(bu 2
+\fB\fC\-b\fR \fIpixels\fP or \fB\fC\-\-buffer=\fR\fIpixels\fP: Buffer size where features are duplicated from adjacent tiles. Units are "screen pixels"—1/256th of the tile width or height. (default 5)
+.IP \(bu 2
+\fB\fC\-pc\fR or \fB\fC\-\-no\-clipping\fR: Don't clip features to the size of the tile. If a feature overlaps the tile's bounds or buffer at all, it is included completely. Be careful: this can produce very large tilesets, especially with large polygons.
+.IP \(bu 2
+\fB\fC\-pD\fR or \fB\fC\-\-no\-duplication\fR: As with \fB\fC\-\-no\-clipping\fR, each feature is included intact instead of cut to tile boundaries. In addition, it is included only in a single tile per zoom level rather than potentially in multiple copies. Clients of the tileset must check adjacent tiles (possibly some distance away) to ensure they have all features.
+.RE
+.SS Reordering features within each tile
+.RS
+.IP \(bu 2
+\fB\fC\-pi\fR or \fB\fC\-\-preserve\-input\-order\fR: Preserve the original input order of features as the drawing order instead of ordering geographically. (This is implemented as a restoration of the original order at the end, so that dot\-dropping is still geographic, which means it also undoes \fB\fC\-ao\fR).
+.IP \(bu 2
+\fB\fC\-ao\fR or \fB\fC\-\-reorder\fR: Reorder features to put ones with the same properties in sequence, to try to get them to coalesce. You probably don't want to use this.
+.IP \(bu 2
+\fB\fC\-ac\fR or \fB\fC\-\-coalesce\fR: Coalesce adjacent line and polygon features that have the same properties. You probably don't want to use this.
+.IP \(bu 2
+\fB\fC\-ar\fR or \fB\fC\-\-reverse\fR: Try reversing the directions of lines to make them coalesce and compress better. You probably don't want to use this.
+.RE
+.SS Adding calculated attributes
+.RS
+.IP \(bu 2
+\fB\fC\-ag\fR or \fB\fC\-\-calculate\-feature\-density\fR: Add a new attribute, \fB\fCtippecanoe_feature_density\fR, to each feature, to record how densely features are spaced in that area of the tile. You can use this attribute in the style to produce a glowing effect where points are densely packed. It can range from 0 in the sparsest areas to 255 in the densest.
+.RE
+.SS Trying to correct bad source geometry
+.RS
+.IP \(bu 2
+\fB\fC\-aw\fR or \fB\fC\-\-detect\-longitude\-wraparound\fR: Detect when adjacent points within a feature jump to the other side of the world, and try to fix the geometry.
+.RE
+.SS Setting or disabling tile size limits
+.RS
+.IP \(bu 2
+\fB\fC\-M\fR \fIbytes\fP or \fB\fC\-\-maximum\-tile\-bytes=\fR\fIbytes\fP: Use the specified number of \fIbytes\fP as the maximum compressed tile size instead of 500K.
+.IP \(bu 2
+\fB\fC\-pf\fR or \fB\fC\-\-no\-feature\-limit\fR: Don't limit tiles to 200,000 features
+.IP \(bu 2
+\fB\fC\-pk\fR or \fB\fC\-\-no\-tile\-size\-limit\fR: Don't limit tiles to 500K bytes
+.IP \(bu 2
+\fB\fC\-pC\fR or \fB\fC\-\-no\-tile\-compression\fR: Don't compress the PBF vector tile data.
+.IP \(bu 2
+\fB\fC\-pg\fR or \fB\fC\-\-no\-tile\-stats\fR: Don't generate the \fB\fCtilestats\fR row in the tileset metadata. Uploads without tilestats \[la]https://github.com/mapbox/mapbox-geostats\[ra] will take longer to process.
+.RE
+.SS Temporary storage
+.RS
+.IP \(bu 2
+\fB\fC\-t\fR \fIdirectory\fP or \fB\fC\-\-temporary\-directory=\fR\fIdirectory\fP: Put the temporary files in \fIdirectory\fP\&.
+If you don't specify, it will use \fB\fC/tmp\fR\&.
+.RE
+.SS Progress indicator
+.RS
+.IP \(bu 2
+\fB\fC\-q\fR or \fB\fC\-\-quiet\fR: Work quietly instead of reporting progress
+.IP \(bu 2
+\fB\fC\-v\fR or \fB\fC\-\-version\fR: Report Tippecanoe's version number
+.RE
+.SS Filters
+.RS
+.IP \(bu 2
+\fB\fC\-C\fR \fIcommand\fP or \fB\fC\-\-prefilter=\fR\fIcommand\fP: Specify a shell filter command to be run at the start of assembling each tile
+.IP \(bu 2
+\fB\fC\-c\fR \fIcommand\fP or \fB\fC\-\-postfilter=\fR\fIcommand\fP: Specify a shell filter command to be run at the end of assembling each tile
+.RE
+.PP
+The pre\- and post\-filter commands allow you to do optional filtering or transformation on the features of each tile
+as it is created. They are shell commands, run with the zoom level, X, and Y as the \fB\fC$1\fR, \fB\fC$2\fR, and \fB\fC$3\fR arguments.
+Future versions of Tippecanoe may add additional arguments for more context.
+.PP
+The features are provided to the filter
+as a series of newline\-delimited GeoJSON objects on the standard input, and \fB\fCtippecanoe\fR expects to read another
+set of GeoJSON features from the filter's standard output.
+.PP
+The prefilter receives the features at the highest available resolution, before line simplification,
+polygon topology repair, gamma calculation, dynamic feature dropping, or other internal processing.
+The postfilter receives the features at tile resolution, after simplification, cleaning, and dropping.
+.PP
+The layer name is provided as part of the \fB\fCtippecanoe\fR element of the feature and must be passed through
+to keep the feature in its correct layer. In the case of the prefilter, the \fB\fCtippecanoe\fR element may also
+contain \fB\fCindex\fR, \fB\fCsequence\fR, and \fB\fCextent\fR elements, which must be passed through for internal operations like
+\fB\fC\-\-drop\-densest\-as\-needed\fR, \fB\fC\-\-drop\-smallest\-as\-needed\fR, and \fB\fC\-\-preserve\-input\-order\fR to work.
+.SS Examples:
+.RS
+.IP \(bu 2
+Make a tileset of the Natural Earth countries to zoom level 5, and also copy the GeoJSON features
+to files in a \fB\fCtiles/z/x/y.geojson\fR directory hierarchy.
+.RE
+.PP
+.RS
+.nf
+tippecanoe \-o countries.mbtiles \-z5 \-C 'mkdir \-p tiles/$1/$2; tee tiles/$1/$2/$3.geojson' ne_10m_admin_0_countries.json
+.fi
+.RE
+.RS
+.IP \(bu 2
+Make a tileset of the Natural Earth countries to zoom level 5, but including only those tiles that
+intersect the bounding box of Germany \[la]https://www.flickr.com/places/info/23424829\[ra]\&.
+(The \fB\fClimit\-tiles\-to\-bbox\fR script is in the Tippecanoe source directory \[la]filters/limit-tiles-to-bbox\[ra]\&.)
+.RE
+.PP
+.RS
+.nf
+tippecanoe \-o countries.mbtiles \-z5 \-C './filters/limit\-tiles\-to\-bbox 5.8662 47.2702 15.0421 55.0581 $*' ne_10m_admin_0_countries.json
+.fi
+.RE
+.RS
+.IP \(bu 2
+Make a tileset of TIGER roads in Tippecanoe County, leaving out all but primary and secondary roads (as classified by TIGER \[la]https://www.census.gov/geo/reference/mtfcc.html\[ra]) below zoom level 11.
+.RE
+.PP
+.RS
+.nf
+tippecanoe \-o roads.mbtiles \-c 'if [ $1 \-lt 11 ]; then grep "\\"MTFCC\\": \\"S1[12]00\\""; else cat; fi' tl_2016_18157_roads.json
+.fi
+.RE
+.SH Environment
+.PP
+Tippecanoe ordinarily uses as many parallel threads as the operating system claims that CPUs are available.
+You can override this number by setting the \fB\fCTIPPECANOE_MAX_THREADS\fR environmental variable.
 .SH GeoJSON extension
 .PP
 Tippecanoe defines a GeoJSON extension that you can use to specify the minimum and/or maximum zoom level
-at which an individual feature will be included in the vector tile dataset being produced.
+at which an individual feature will be included in the vector tileset being produced.
 If you have a feature like this:
 .PP
 .RS
@@ -159,7 +407,26 @@ If you have a feature like this:
 .PP
 with a \fB\fCtippecanoe\fR object specifiying a \fB\fCmaxzoom\fR of 9 and a \fB\fCminzoom\fR of 4, the feature
 will only appear in the vector tiles for zoom levels 4 through 9. Note that the \fB\fCtippecanoe\fR
-object belongs to the Feature, not to its \fB\fCproperties\fR\&.
+object belongs to the Feature, not to its \fB\fCproperties\fR\&. If you specify a \fB\fCminzoom\fR for a feature,
+it will be preserved down to that zoom level even if dot\-dropping with \fB\fC\-r\fR would otherwise have
+dropped it.
+.PP
+You can also specify a layer name in the \fB\fCtippecanoe\fR object, which will take precedence over
+the filename or name specified using \fB\fC\-\-layer\fR, like this:
+.PP
+.RS
+.nf
+{
+    "type" : "Feature",
+    "tippecanoe" : { "layer" : "streets" },
+    "properties" : { "FULLNAME" : "N Vasco Rd" },
+    "geometry" : {
+        "type" : "LineString",
+        "coordinates" : [ [ \-121.733350, 37.767671 ], [ \-121.733600, 37.767483 ], [ \-121.733131, 37.766952 ] ]
+    }
+}
+.fi
+.RE
 .SH Point styling
 .PP
 To provide a consistent density gradient as you zoom, the Mapbox Studio style needs to be
@@ -167,7 +434,7 @@ coordinated with the base zoom level and dot\-dropping rate. You can use this sh
 calculate the appropriate marker\-width at high zoom levels to match the fraction of dots
 that were dropped at low zoom levels.
 .PP
-If you used \fB\fC\-z\fR to change the base zoom level or \fB\fC\-r\fR to change the
+If you used \fB\fC\-B\fR or \fB\fC\-z\fR to change the base zoom level or \fB\fC\-r\fR to change the
 dot\-dropping rate, replace them in the \fB\fCbasezoom\fR and \fB\fCrate\fR below.
 .PP
 .RS
@@ -176,6 +443,7 @@ awk 'BEGIN {
     dotsize = 2;    # up to you to decide
     basezoom = 14;  # tippecanoe \-z 14
     rate = 2.5;     # tippecanoe \-r 2.5
+
     print "  marker\-line\-width: 0;";
     print "  marker\-ignore\-placement: true;";
     print "  marker\-allow\-overlap: true;";
@@ -183,6 +451,7 @@ awk 'BEGIN {
     for (i = basezoom + 1; i <= 22; i++) {
         print "  [zoom >= " i "] { marker\-width: " (dotsize * exp(log(sqrt(rate)) * (i \- basezoom))) "; }";
     }
+
     exit(0);
 }'
 .fi
@@ -192,7 +461,9 @@ awk 'BEGIN {
 At every zoom level, line and polygon features are subjected to Douglas\-Peucker
 simplification to the resolution of the tile.
 .PP
-For point features, it drops 1/2.5 of the dots for each zoom level above the base.
+For point features, it drops 1/2.5 of the dots for each zoom level above the
+point base zoom (which is normally the same as the \fB\fC\-z\fR max zoom, but can be
+a different zoom specified with \fB\fC\-B\fR if you have precise but sparse data).
 I don't know why 2.5 is the appropriate number, but the densities of many different
 data sets fall off at about this same rate. You can use \-r to specify a different rate.
 .PP
@@ -204,37 +475,28 @@ For line features, it drops any features that are too small to draw at all.
 This still leaves the lower zooms too dark (and too dense for the 500K tile limit,
 in some places), so I need to figure out an equitable way to throw features away.
 .PP
-Any polygons that are smaller than a minimum area (currently 4 square subpixels) will
+Unless you specify \fB\fC\-\-no\-tiny\-polygon\-reduction\fR,
+any polygons that are smaller than a minimum area (currently 4 square subpixels) will
 have their probability diffused, so that some of them will be drawn as a square of
 this minimum size and others will not be drawn at all, preserving the total area that
 all of them should have had together.
 .PP
 Features in the same tile that share the same type and attributes are coalesced
-together into a single geometry. You are strongly encouraged to use \-x to exclude
+together into a single geometry if you use \fB\fC\-\-coalesce\fR\&. You are strongly encouraged to use \-x to exclude
 any unnecessary properties to reduce wasted file size.
 .PP
 If a tile is larger than 500K, it will try encoding that tile at progressively
 lower resolutions before failing if it still doesn't fit.
 .SH Development
 .PP
-Requires protoc and sqlite3. Rebuilding the manpage
+Requires sqlite3 and zlib (should already be installed on MacOS). Rebuilding the manpage
 uses md2man (\fB\fCgem install md2man\fR).
 .PP
-MacOS:
-.PP
-.RS
-.nf
-brew install protobuf
-.fi
-.RE
-.PP
 Linux:
 .PP
 .RS
 .nf
-sudo apt\-get install libprotobuf\-dev
-sudo apt\-get install protobuf\-compiler
-sudo apt\-get install libsqlite3\-dev
+sudo apt\-get install build\-essential libsqlite3\-dev zlib1g\-dev
 .fi
 .RE
 .PP
@@ -253,37 +515,122 @@ and perhaps
 make install
 .fi
 .RE
-.SH Examples
 .PP
-Check out some examples of maps made with tippecanoe
-\[la]MADE_WITH.md\[ra]
-.SH Name
+Tippecanoe now requires features from the 2011 C++ standard. If your compiler is older than
+that, you will need to install a newer one. On MacOS, updating to the lastest XCode should
+get you a new enough version of \fB\fCclang++\fR\&. On Linux, you should be able to upgrade \fB\fCg++\fR with
 .PP
-The name is a joking reference
-\[la]http://en.wikipedia.org/wiki/Tippecanoe_and_Tyler_Too\[ra] to a "tiler" for making map tiles.
-.SH tile\-join
-.PP
-Tile\-join is a tool for joining new attributes from a CSV file to features that
-have already been tiled with tippecanoe. It reads the tiles from an existing .mbtiles
-file, matches them against the records of the CSV, and writes out a new tileset.
-.PP
-The options are:
 .RS
-.IP \(bu 2
-\-o \fIout.mbtiles\fP: Write the new tiles to the specified .mbtiles file
-.IP \(bu 2
-\-f: Remove \fIout.mbtiles\fP if it already exists
-.IP \(bu 2
-\-c \fImatch.csv\fP: Use \fImatch.csv\fP as the source for new attributes to join to the features. The first line of the file should be the key names; the other lines are values. The first column is the one to match against the existing features; the other columns are the new data to add.
-.IP \(bu 2
-\-x \fIkey\fP: Remove attributes of type \fIkey\fP from the output. You can use this to remove the field you are matching against if you no longer need it after joining, or to remove any other attributes you don't want.
-.IP \(bu 2
-\-i: Only include features that matched the CSV.
+.nf
+sudo add\-apt\-repository \-y ppa:ubuntu\-toolchain\-r/test
+sudo apt\-get update \-y
+sudo apt\-get install \-y g++\-5
+export CXX=g++\-5
+.fi
+.RE
+.SH Docker Image
+.PP
+A tippecanoe Docker image can be built from source and executed as a task to
+automatically install dependencies and allow tippecanoe to run on any system
+supported by Docker.
+.PP
+.RS
+.nf
+$ docker build \-t tippecanoe:latest .
+$ docker run \-it \-\-rm \\
+  \-v /tiledata:/data \\
+  tippecanoe:latest \\
+  tippecanoe \-\-output=/data/output.mbtiles /data/example.geojson
+.fi
 .RE
 .PP
-Because tile\-join just copies the geometries to the new .mbtiles without processing them,
+The commands above will build a Docker image from the source and compile the
+latest version. The image supports all tippecanoe flags and options.
+.SH Examples
+.PP
+Check out some examples of maps made with tippecanoe \[la]MADE_WITH.md\[ra]
+.SH Name
+.PP
+The name is a joking reference \[la]http://en.wikipedia.org/wiki/Tippecanoe_and_Tyler_Too\[ra] to a "tiler" for making map tiles.
+.SH tile\-join
+.PP
+Tile\-join is a tool for copying and merging vector mbtiles files and for
+joining new attributes from a CSV file to existing features in them.
+.PP
+It reads the tiles from an
+existing .mbtiles file or a directory of tiles, matches them against the
+records of the CSV (if one is specified), and writes out a new tileset.
+.PP
+If you specify multiple source mbtiles files or source directories of tiles,
+all the sources are read and their combined contents are written to the new
+mbtiles output. If they define the same layers or the same tiles, the layers
+or tiles are merged.
+.PP
+The options are:
+.SS Output tileset
+.RS
+.IP \(bu 2
+\fB\fC\-o\fR \fIout.mbtiles\fP or \fB\fC\-\-output=\fR\fIout.mbtiles\fP: Write the new tiles to the specified .mbtiles file.
+.IP \(bu 2
+\fB\fC\-e\fR \fIdirectory\fP or \fB\fC\-\-output\-to\-directory=\fR\fIdirectory\fP: Write the new tiles to the specified directory instead of to an mbtiles file.
+.IP \(bu 2
+\fB\fC\-f\fR or \fB\fC\-\-force\fR: Remove \fIout.mbtiles\fP if it already exists.
+.RE
+.SS Tileset description and attribution
+.RS
+.IP \(bu 2
+\fB\fC\-A\fR \fIattribution\fP or \fB\fC\-\-attribution=\fR\fIattribution\fP: Set the attribution string.
+.IP \(bu 2
+\fB\fC\-n\fR \fIname\fP or \fB\fC\-\-name=\fR\fIname\fP: Set the tileset name.
+.IP \(bu 2
+\fB\fC\-N\fR \fIdescription\fP or \fB\fC\-\-description=\fR\fIdescription\fP: Set the tileset description.
+.RE
+.SS Layer filtering and naming
+.RS
+.IP \(bu 2
+\fB\fC\-l\fR \fIlayer\fP or \fB\fC\-\-layer=\fR\fIlayer\fP: Include the named layer in the output. You can specify multiple \fB\fC\-l\fR options to keep multiple layers. If you don't specify, they will all be retained.
+.IP \(bu 2
+\fB\fC\-L\fR \fIlayer\fP or \fB\fC\-\-exclude\-layer=\fR\fIlayer\fP: Remove the named layer from the output. You can specify multiple \fB\fC\-L\fR options to remove multiple layers.
+.IP \(bu 2
+\fB\fC\-R\fR\fIold\fP\fB\fC:\fR\fInew\fP or \fB\fC\-\-rename\-layer=\fR\fIold\fP\fB\fC:\fR\fInew\fP: Rename the layer named \fIold\fP to be named \fInew\fP instead. You can specify multiple \fB\fC\-R\fR options to rename multiple layers. Renaming happens before filtering.
+.RE
+.SS Zoom levels
+.RS
+.IP \(bu 2
+\fB\fC\-z\fR \fIzoom\fP or \fB\fC\-\-maximum\-zoom=\fR\fIzoom\fP: Don't copy tiles from higher zoom levels than the specified zoom
+.IP \(bu 2
+\fB\fC\-Z\fR \fIzoom\fP or \fB\fC\-\-minimum\-zoom=\fR\fIzoom\fP: Don't copy tiles from lower zoom levels than the specified zoom
+.RE
+.SS Merging attributes from a CSV file
+.RS
+.IP \(bu 2
+\fB\fC\-c\fR \fImatch\fP\fB\fC\&.csv\fR or \fB\fC\-\-csv=\fR\fImatch\fP\fB\fC\&.csv\fR: Use \fImatch\fP\fB\fC\&.csv\fR as the source for new attributes to join to the features. The first line of the file should be the key names; the other lines are values. The first column is the one to match against the existing features; the other columns are the new data to add.
+.RE
+.SS Filtering features and feature attributes
+.RS
+.IP \(bu 2
+\fB\fC\-x\fR \fIkey\fP or \fB\fC\-\-exclude=\fR\fIkey\fP: Remove attributes of type \fIkey\fP from the output. You can use this to remove the field you are matching against if you no longer need it after joining, or to remove any other attributes you don't want.
+.IP \(bu 2
+\fB\fC\-i\fR or \fB\fC\-\-if\-matched\fR: Only include features that matched the CSV.
+.IP \(bu 2
+\fB\fC\-j\fR \fIfilter\fP or \fB\fC\-\-feature\-filter\fR=\fIfilter\fP: Check features against a per\-layer filter (as defined in the Mapbox GL Style Specification \[la]https://www.mapbox.com/mapbox-gl-js/style-spec/#types-filter\[ra]) and only include those that match. Any features in layers that have no filter specified will be passed through. Filters for the layer \fB\fC"*"\fR apply to all layers.
+.IP \(bu 2
+\fB\fC\-J\fR \fIfilter\-file\fP or \fB\fC\-\-feature\-filter\-file\fR=\fIfilter\-file\fP: Like \fB\fC\-j\fR, but read the filter from a file.
+.RE
+.SS Setting or disabling tile size limits
+.RS
+.IP \(bu 2
+\fB\fC\-pk\fR or \fB\fC\-\-no\-tile\-size\-limit\fR: Don't skip tiles larger than 500K.
+.IP \(bu 2
+\fB\fC\-pC\fR or \fB\fC\-\-no\-tile\-compression\fR: Don't compress the PBF vector tile data.
+.IP \(bu 2
+\fB\fC\-pg\fR or \fB\fC\-\-no\-tile\-stats\fR: Don't generate the \fB\fCtilestats\fR row in the tileset metadata. Uploads without tilestats \[la]https://github.com/mapbox/mapbox-geostats\[ra] will take longer to process.
+.RE
+.PP
+Because tile\-join just copies the geometries to the new .mbtiles without processing them
+(except to rescale the extents if necessary),
 it doesn't have any of tippecanoe's recourses if the new tiles are bigger than the 500K tile limit.
-If a tile is too big, it is just left out of the new tileset.
+If a tile is too big and you haven't specified \fB\fC\-pk\fR, it is just left out of the new tileset.
 .SH Example
 .PP
 Imagine you have a tileset of census blocks:
@@ -336,3 +683,57 @@ Then you can join those populations to the geometries and discard the no\-longer
 \&./tile\-join \-o population.mbtiles \-x GEOID10 \-c population.csv tl_2010_06001_tabblock10.mbtiles
 .fi
 .RE
+.SH tippecanoe\-enumerate
+.PP
+The \fB\fCtippecanoe\-enumerate\fR utility lists the tiles that an \fB\fCmbtiles\fR file defines.
+Each line of the output lists the name of the \fB\fCmbtiles\fR file and the zoom, x, and y
+coordinates of one of the tiles. It does basically the same thing as
+.PP
+.RS
+.nf
+select zoom_level, tile_column, (1 << zoom_level) \- 1 \- tile_row from tiles;
+.fi
+.RE
+.PP
+on the file in sqlite3.
+.SH tippecanoe\-decode
+.PP
+The \fB\fCtippecanoe\-decode\fR utility turns vector mbtiles back to GeoJSON. You can use it either
+on an entire file:
+.PP
+.RS
+.nf
+tippecanoe\-decode file.mbtiles
+.fi
+.RE
+.PP
+or on an individual tile:
+.PP
+.RS
+.nf
+tippecanoe\-decode file.mbtiles zoom x y
+tippecanoe\-decode file.vector.pbf zoom x y
+.fi
+.RE
+.PP
+If you decode an entire file, you get a nested \fB\fCFeatureCollection\fR identifying each
+tile and layer separately. Note that the same features generally appear at all zooms,
+so the output for the file will have many copies of the same features at different
+resolutions.
+.SS Options
+.RS
+.IP \(bu 2
+\fB\fC\-s\fR \fIprojection\fP or \fB\fC\-\-projection=\fR\fIprojection\fP: Specify the projection of the output data. Currently supported are EPSG:4326 (WGS84, the default) and EPSG:3857 (Web Mercator).
+.IP \(bu 2
+\fB\fC\-z\fR \fImaxzoom\fP or \fB\fC\-\-maximum\-zoom=\fR\fImaxzoom\fP: Specify the highest zoom level to decode from the tileset
+.IP \(bu 2
+\fB\fC\-Z\fR \fIminzoom\fP or \fB\fC\-\-minimum\-zoom=\fR\fIminzoom\fP: Specify the lowest zoom level to decode from the tileset
+.IP \(bu 2
+\fB\fC\-l\fR \fIlayer\fP or \fB\fC\-\-layer=\fR\fIlayer\fP: Decode only layers with the specified names. (Multiple \fB\fC\-l\fR options can be specified.)
+.IP \(bu 2
+\fB\fC\-c\fR or \fB\fC\-\-tag\-layer\-and\-zoom\fR: Include each feature's layer and zoom level as part of its \fB\fCtippecanoe\fR object rather than as a FeatureCollection wrapper
+.IP \(bu 2
+\fB\fC\-S\fR or \fB\fC\-\-stats\fR: Just report statistics about each tile's size and the number of features in it, as a JSON structure.
+.IP \(bu 2
+\fB\fC\-f\fR or \fB\fC\-\-force\fR: Decode tiles even if polygon ring order or closure problems are detected
+.RE

mapbox/LICENSE-geometry.hpp

@@ -0,0 +1,13 @@
+Copyright (c) 2016, Mapbox
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

mapbox/LICENSE-variant

@@ -0,0 +1,25 @@
+Copyright (c) MapBox
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+- Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+- Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimer in the documentation and/or
+  other materials provided with the distribution.
+- Neither the name "MapBox" nor the names of its contributors may be
+  used to endorse or promote products derived from this software without
+  specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

mapbox/LICENSE-wagyu

@@ -0,0 +1,37 @@
+Parts of the code in the Wagyu Library are derived from the version of the 
+Clipper Library by Angus Johnson listed below.
+
+Author    :  Angus Johnson
+Version   :  6.4.0
+Date      :  2 July 2015
+Website   :  http://www.angusj.com
+
+Copyright for portions of the derived code in the Wagyu library are held 
+by Angus Johnson, 2010-2015. All other copyright for the Wagyu Library are held by 
+Mapbox, 2016. This code is published in accordance with, and retains the same license
+as the Clipper Library by Angus Johnson.
+
+Copyright (c) 2010-2015, Angus Johnson
+Copyright (c) 2016, Mapbox
+
+Permission is hereby granted, free of charge, to any person or organization
+obtaining a copy of the software and accompanying documentation covered by
+this license (the "Software") to use, reproduce, display, distribute,
+execute, and transmit the Software, and to prepare derivative works of the
+Software, and to permit third-parties to whom the Software is furnished to
+do so, all subject to the following:
+
+The copyright notices in the Software and this entire statement, including
+the above license grant, this restriction and the following disclaimer,
+must be included in all copies of the Software, in whole or in part, and
+all derivative works of the Software, unless such copies or derivative
+works are solely in the form of machine-executable object code generated by
+a source language processor.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
+SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
+FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

mapbox/geometry.hpp

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/line_string.hpp>
+#include <mapbox/geometry/polygon.hpp>
+#include <mapbox/geometry/multi_point.hpp>
+#include <mapbox/geometry/multi_line_string.hpp>
+#include <mapbox/geometry/multi_polygon.hpp>
+#include <mapbox/geometry/geometry.hpp>
+#include <mapbox/geometry/feature.hpp>
+#include <mapbox/geometry/point_arithmetic.hpp>
+#include <mapbox/geometry/for_each_point.hpp>
+#include <mapbox/geometry/envelope.hpp>

mapbox/geometry/box.hpp

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <mapbox/geometry/point.hpp>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T>
+struct box
+{
+    using point_type = point<T>;
+
+    constexpr box(point_type const& min_, point_type const& max_)
+        : min(min_), max(max_)
+    {}
+
+    point_type min;
+    point_type max;
+};
+
+template <typename T>
+constexpr bool operator==(box<T> const& lhs, box<T> const& rhs)
+{
+    return lhs.min == rhs.min && lhs.max == rhs.max;
+}
+
+template <typename T>
+constexpr bool operator!=(box<T> const& lhs, box<T> const& rhs)
+{
+    return lhs.min != rhs.min || lhs.max != rhs.max;
+}
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/envelope.hpp

@@ -0,0 +1,33 @@
+#pragma once
+
+#include <mapbox/geometry/box.hpp>
+#include <mapbox/geometry/for_each_point.hpp>
+
+#include <limits>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename G, typename T = typename G::coordinate_type>
+box<T> envelope(G const& geometry)
+{
+    using limits = std::numeric_limits<T>;
+
+    T min_t = limits::has_infinity ? -limits::infinity() : limits::min();
+    T max_t = limits::has_infinity ?  limits::infinity() : limits::max();
+
+    point<T> min(max_t, max_t);
+    point<T> max(min_t, min_t);
+
+    for_each_point(geometry, [&] (point<T> const& point) {
+        if (min.x > point.x) min.x = point.x;
+        if (min.y > point.y) min.y = point.y;
+        if (max.x < point.x) max.x = point.x;
+        if (max.y < point.y) max.y = point.y;
+    });
+
+    return box<T>(min, max);
+}
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/feature.hpp

@@ -0,0 +1,81 @@
+#pragma once
+
+#include <mapbox/geometry/geometry.hpp>
+
+#include <mapbox/variant.hpp>
+
+#include <cstdint>
+#include <string>
+#include <vector>
+#include <unordered_map>
+#include <experimental/optional>
+
+namespace mapbox {
+namespace geometry {
+
+struct value;
+
+struct null_value_t
+{
+    constexpr null_value_t() {}
+    constexpr null_value_t(std::nullptr_t) {}
+};
+
+constexpr bool operator==(const null_value_t&, const null_value_t&) { return true; }
+constexpr bool operator!=(const null_value_t&, const null_value_t&) { return false; }
+
+constexpr null_value_t null_value = null_value_t();
+
+// Multiple numeric types (uint64_t, int64_t, double) are present in order to support
+// the widest possible range of JSON numbers, which do not have a maximum range.
+// Implementations that produce `value`s should use that order for type preference,
+// using uint64_t for positive integers, int64_t for negative integers, and double
+// for non-integers and integers outside the range of 64 bits.
+using value_base = mapbox::util::variant<null_value_t, bool, uint64_t, int64_t, double, std::string,
+                                         mapbox::util::recursive_wrapper<std::vector<value>>,
+                                         mapbox::util::recursive_wrapper<std::unordered_map<std::string, value>>>;
+
+struct value : value_base
+{
+    using value_base::value_base;
+};
+
+using property_map = std::unordered_map<std::string, value>;
+
+// The same considerations and requirement for numeric types apply as for `value_base`.
+using identifier = mapbox::util::variant<uint64_t, int64_t, double, std::string>;
+
+template <class T>
+struct feature
+{
+    using coordinate_type = T;
+    using geometry_type = mapbox::geometry::geometry<T>; // Fully qualified to avoid GCC -fpermissive error.
+
+    geometry_type geometry;
+    property_map properties {};
+    std::experimental::optional<identifier> id {};
+};
+
+template <class T>
+constexpr bool operator==(feature<T> const& lhs, feature<T> const& rhs)
+{
+    return lhs.id == rhs.id && lhs.geometry == rhs.geometry && lhs.properties == rhs.properties;
+}
+
+template <class T>
+constexpr bool operator!=(feature<T> const& lhs, feature<T> const& rhs)
+{
+    return !(lhs == rhs);
+}
+
+template <class T, template <typename...> class Cont = std::vector>
+struct feature_collection : Cont<feature<T>>
+{
+    using coordinate_type = T;
+    using feature_type = feature<T>;
+    using container_type = Cont<feature_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/for_each_point.hpp

@@ -0,0 +1,45 @@
+#pragma once
+
+#include <mapbox/geometry/geometry.hpp>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename Point, typename F>
+auto for_each_point(Point&& point, F&& f)
+    -> decltype(point.x, point.y, void())
+{
+    f(std::forward<Point>(point));
+}
+
+template <typename Container, typename F>
+auto for_each_point(Container&& container, F&& f)
+    -> decltype(container.begin(), container.end(), void());
+
+template <typename...Types, typename F>
+void for_each_point(mapbox::util::variant<Types...> const& geom, F&& f)
+{
+    mapbox::util::variant<Types...>::visit(geom, [&] (auto const& g) {
+        for_each_point(g, f);
+    });
+}
+
+template <typename...Types, typename F>
+void for_each_point(mapbox::util::variant<Types...> & geom, F&& f)
+{
+    mapbox::util::variant<Types...>::visit(geom, [&] (auto & g) {
+        for_each_point(g, f);
+    });
+}
+
+template <typename Container, typename F>
+auto for_each_point(Container&& container, F&& f)
+    -> decltype(container.begin(), container.end(), void())
+{
+    for (auto& e: container) {
+        for_each_point(e, f);
+    }
+}
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/geometry.hpp

@@ -0,0 +1,53 @@
+#pragma once
+
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/line_string.hpp>
+#include <mapbox/geometry/polygon.hpp>
+#include <mapbox/geometry/multi_point.hpp>
+#include <mapbox/geometry/multi_line_string.hpp>
+#include <mapbox/geometry/multi_polygon.hpp>
+
+#include <mapbox/variant.hpp>
+
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct geometry_collection;
+
+template <typename T>
+using geometry_base = mapbox::util::variant<point<T>,
+                                            line_string<T>,
+                                            polygon<T>,
+                                            multi_point<T>,
+                                            multi_line_string<T>,
+                                            multi_polygon<T>,
+                                            geometry_collection<T>>;
+
+template <typename T>
+struct geometry : geometry_base<T>
+{
+    using coordinate_type = T;
+    using geometry_base<T>::geometry_base;
+
+    /*
+     * The default constructor would create a point geometry with default-constructed coordinates;
+     * i.e. (0, 0). Since this is not particularly useful, and could hide bugs, it is disabled.
+     */
+    geometry() = delete;
+};
+
+template <typename T, template <typename...> class Cont>
+struct geometry_collection : Cont<geometry<T>>
+{
+    using coordinate_type = T;
+    using geometry_type = geometry<T>;
+    using container_type = Cont<geometry_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/line_string.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+// mapbox
+#include <mapbox/geometry/point.hpp>
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct line_string : Cont<point<T> >
+{
+    using coordinate_type = T;
+    using point_type = point<T>;
+    using container_type = Cont<point_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/multi_line_string.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+// mapbox
+#include <mapbox/geometry/line_string.hpp>
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct multi_line_string : Cont<line_string<T>>
+{
+    using coordinate_type = T;
+    using line_string_type = line_string<T>;
+    using container_type = Cont<line_string_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/multi_point.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+// mapbox
+#include <mapbox/geometry/point.hpp>
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct multi_point : Cont<point<T>>
+{
+    using coordinate_type = T;
+    using point_type = point<T>;
+    using container_type = Cont<point_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/multi_polygon.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+// mapbox
+#include <mapbox/geometry/polygon.hpp>
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct multi_polygon : Cont<polygon<T>>
+{
+    using coordinate_type = T;
+    using polygon_type = polygon<T>;
+    using container_type = Cont<polygon_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/point.hpp

@@ -0,0 +1,35 @@
+#pragma once
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T>
+struct point
+{
+    using coordinate_type = T;
+
+    constexpr point()
+        : x(), y()
+    {}
+    constexpr point(T x_, T y_)
+        : x(x_), y(y_)
+    {}
+
+    T x;
+    T y;
+};
+
+template <typename T>
+constexpr bool operator==(point<T> const& lhs, point<T> const& rhs)
+{
+    return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+
+template <typename T>
+constexpr bool operator!=(point<T> const& lhs, point<T> const& rhs)
+{
+    return !(lhs == rhs);
+}
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/point_arithmetic.hpp

@@ -0,0 +1,119 @@
+#pragma once
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T>
+constexpr point<T> operator+(point<T> const& lhs, point<T> const& rhs)
+{
+    return point<T>(lhs.x + rhs.x, lhs.y + rhs.y);
+}
+
+template <typename T>
+constexpr point<T> operator+(point<T> const& lhs, T const& rhs)
+{
+    return point<T>(lhs.x + rhs, lhs.y + rhs);
+}
+
+template <typename T>
+constexpr point<T> operator-(point<T> const& lhs, point<T> const& rhs)
+{
+    return point<T>(lhs.x - rhs.x, lhs.y - rhs.y);
+}
+
+template <typename T>
+constexpr point<T> operator-(point<T> const& lhs, T const& rhs)
+{
+    return point<T>(lhs.x - rhs, lhs.y - rhs);
+}
+
+template <typename T>
+constexpr point<T> operator*(point<T> const& lhs, point<T> const& rhs)
+{
+    return point<T>(lhs.x * rhs.x, lhs.y * rhs.y);
+}
+
+template <typename T>
+constexpr point<T> operator*(point<T> const& lhs, T const& rhs)
+{
+    return point<T>(lhs.x * rhs, lhs.y * rhs);
+}
+
+template <typename T>
+constexpr point<T> operator/(point<T> const& lhs, point<T> const& rhs)
+{
+    return point<T>(lhs.x / rhs.x, lhs.y / rhs.y);
+}
+
+template <typename T>
+constexpr point<T> operator/(point<T> const& lhs, T const& rhs)
+{
+    return point<T>(lhs.x / rhs, lhs.y / rhs);
+}
+
+template <typename T>
+constexpr point<T>& operator+=(point<T>& lhs, point<T> const& rhs)
+{
+    lhs.x += rhs.x;
+    lhs.y += rhs.y;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator+=(point<T>& lhs, T const& rhs)
+{
+    lhs.x += rhs;
+    lhs.y += rhs;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator-=(point<T>& lhs, point<T> const& rhs)
+{
+    lhs.x -= rhs.x;
+    lhs.y -= rhs.y;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator-=(point<T>& lhs, T const& rhs)
+{
+    lhs.x -= rhs;
+    lhs.y -= rhs;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator*=(point<T>& lhs, point<T> const& rhs)
+{
+    lhs.x *= rhs.x;
+    lhs.y *= rhs.y;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator*=(point<T>& lhs, T const& rhs)
+{
+    lhs.x *= rhs;
+    lhs.y *= rhs;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator/=(point<T>& lhs, point<T> const& rhs)
+{
+    lhs.x /= rhs.x;
+    lhs.y /= rhs.y;
+    return lhs;
+}
+
+template <typename T>
+constexpr point<T>& operator/=(point<T>& lhs, T const& rhs)
+{
+    lhs.x /= rhs;
+    lhs.y /= rhs;
+    return lhs;
+}
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/polygon.hpp

@@ -0,0 +1,31 @@
+#pragma once
+
+// mapbox
+#include <mapbox/geometry/point.hpp>
+
+// stl
+#include <vector>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct linear_ring : Cont<point<T>>
+{
+    using coordinate_type = T;
+    using point_type = point<T>;
+    using container_type = Cont<point_type>;
+    using container_type::container_type;
+};
+
+template <typename T, template <typename...> class Cont = std::vector>
+struct polygon : Cont<linear_ring<T>>
+{
+    using coordinate_type = T;
+    using linear_ring_type = linear_ring<T>;
+    using container_type = Cont<linear_ring_type>;
+    using container_type::container_type;
+};
+
+} // namespace geometry
+} // namespace mapbox

mapbox/geometry/snap_rounding.hpp

@@ -0,0 +1,466 @@
+#include <mapbox/geometry/geometry.hpp>
+#include <math.h>
+#include <map>
+#include <set>
+#include <vector>
+#include <algorithm>
+#include <cmath>
+
+namespace mapbox {
+namespace geometry {
+
+template <typename T>
+void add_vertical(size_t intermediate, size_t which_end, size_t into, std::vector<std::vector<point<T>>> &segments, bool &again, std::vector<size_t> &nexts) {
+	again = true;
+	std::vector<point<T>> dv;
+	dv.push_back(segments[intermediate][which_end]);
+	dv.push_back(segments[into][1]);
+	segments.push_back(dv);
+	segments[into][1] = segments[intermediate][which_end];
+	nexts.push_back(nexts[into]);
+	nexts[into] = nexts.size() - 1;
+}
+
+template <typename T>
+void add_horizontal(size_t intermediate, size_t which_end, size_t into, std::vector<std::vector<point<T>>> &segments, bool &again, std::vector<size_t> &nexts) {
+	again = true;
+
+	T x = segments[intermediate][which_end].x;
+	T y = segments[intermediate][0].y +
+	      (segments[intermediate][which_end].x - segments[intermediate][0].x) *
+		      (segments[intermediate][1].y - segments[intermediate][0].y) /
+		      (segments[intermediate][1].x - segments[intermediate][0].x);
+	point<T> d(x, y);
+
+	std::vector<point<T>> dv;
+	dv.push_back(d);
+	dv.push_back(segments[into][1]);
+	segments.push_back(dv);
+	segments[into][1] = d;
+	nexts.push_back(nexts[into]);
+	nexts[into] = nexts.size() - 1;
+}
+
+template <typename T>
+void warn(std::vector<std::vector<point<T>>> &segments, size_t a, size_t b, bool do_warn) {
+	if (do_warn) {
+		fprintf(stderr, "%lld,%lld to %lld,%lld intersects %lld,%lld to %lld,%lld\n",
+			(long long) segments[a][0].x, (long long) segments[a][0].y,
+			(long long) segments[a][1].x, (long long) segments[a][1].y,
+			(long long) segments[b][0].x, (long long) segments[b][0].y,
+			(long long) segments[b][1].x, (long long) segments[b][1].y);
+	}
+}
+
+template <typename T>
+void check_intersection(std::vector<std::vector<point<T>>> &segments, size_t a, size_t b, bool &again, std::vector<size_t> &nexts, bool do_warn, bool endpoint_ok) {
+	T s10_x = segments[a][1].x - segments[a][0].x;
+	T s10_y = segments[a][1].y - segments[a][0].y;
+	T s32_x = segments[b][1].x - segments[b][0].x;
+	T s32_y = segments[b][1].y - segments[b][0].y;
+
+	// http://stackoverflow.com/questions/563198/how-do-you-detect-where-two-line-segments-intersect
+	T denom = s10_x * s32_y - s32_x * s10_y;
+
+	if (denom == 0) {
+		// They are parallel or collinear. Find out if they are collinear.
+		// http://www.cpsc.ucalgary.ca/~marina/papers/Segment_intersection.ps
+
+		T ccw =
+			segments[a][0].x * segments[a][1].y +
+			segments[a][1].x * segments[b][0].y +
+			segments[b][0].x * segments[a][0].y -
+			segments[a][0].x * segments[b][0].y -
+			segments[a][1].x * segments[a][0].y -
+			segments[b][0].x * segments[a][1].y;
+
+		if (ccw == 0) {
+			if (segments[a][0].x == segments[a][1].x) {
+				// Vertical
+
+				T amin, amax, bmin, bmax;
+				if (segments[a][0].y < segments[a][1].y) {
+					amin = segments[a][0].y;
+					amax = segments[a][1].y;
+				} else {
+					amin = segments[a][1].y;
+					amax = segments[a][0].y;
+				}
+				if (segments[b][0].y < segments[b][1].y) {
+					bmin = segments[b][0].y;
+					bmax = segments[b][1].y;
+				} else {
+					bmin = segments[b][1].y;
+					bmax = segments[b][0].y;
+				}
+
+				// All of these transformations preserve verticality so we can check multiple cases
+				if (segments[b][0].y > amin && segments[b][0].y < amax) {
+					// B0 is in A
+					warn(segments, a, b, do_warn);
+					add_vertical(b, 0, a, segments, again, nexts);
+				}
+				if (segments[b][1].y > amin && segments[b][1].y < amax) {
+					// B1 is in A
+					warn(segments, a, b, do_warn);
+					add_vertical(b, 1, a, segments, again, nexts);
+				}
+				if (segments[a][0].y > bmin && segments[a][0].y < bmax) {
+					// A0 is in B
+					warn(segments, a, b, do_warn);
+					add_vertical(a, 0, b, segments, again, nexts);
+				}
+				if (segments[a][1].y > bmin && segments[a][1].y < bmax) {
+					// A1 is in B
+					warn(segments, a, b, do_warn);
+					add_vertical(a, 1, b, segments, again, nexts);
+				}
+			} else {
+				// Horizontal or diagonal
+
+				T amin, amax, bmin, bmax;
+				if (segments[a][0].x < segments[a][1].x) {
+					amin = segments[a][0].x;
+					amax = segments[a][1].x;
+				} else {
+					amin = segments[a][1].x;
+					amax = segments[a][0].x;
+				}
+				if (segments[b][0].x < segments[b][1].x) {
+					bmin = segments[b][0].x;
+					bmax = segments[b][1].x;
+				} else {
+					bmin = segments[b][1].x;
+					bmax = segments[b][0].x;
+				}
+
+				// Don't check multiples, because rounding may corrupt collinearity
+				if (segments[b][0].x > amin && segments[b][0].x < amax) {
+					// B0 is in A
+					add_horizontal(b, 0, a, segments, again, nexts);
+					warn(segments, a, b, do_warn);
+				} else if (segments[b][1].x > amin && segments[b][1].x < amax) {
+					// B1 is in A
+					add_horizontal(b, 1, a, segments, again, nexts);
+					warn(segments, a, b, do_warn);
+				} else if (segments[a][0].x > bmin && segments[a][0].x < bmax) {
+					// A0 is in B
+					warn(segments, a, b, do_warn);
+					add_horizontal(a, 0, b, segments, again, nexts);
+				} else if (segments[a][1].x > bmin && segments[a][1].x < bmax) {
+					// A1 is in B
+					warn(segments, a, b, do_warn);
+					add_horizontal(a, 1, b, segments, again, nexts);
+				}
+			}
+		}
+	} else {
+		// Neither parallel nor collinear, so may intersect at a single point
+
+		T s02_x = segments[a][0].x - segments[b][0].x;
+		T s02_y = segments[a][0].y - segments[b][0].y;
+
+		double s = (s10_x * s02_y - s10_y * s02_x) / (long double) denom;
+		double t = (s32_x * s02_y - s32_y * s02_x) / (long double) denom;
+
+		if (t >= 0 && t <= 1 && s >= 0 && s <= 1) {
+			T x = (T) round(segments[a][0].x + t * s10_x);
+			T y = (T) round(segments[a][0].y + t * s10_y);
+
+			if ((t > 0 && t < 1 && s > 0 && s < 1) || !endpoint_ok) {
+				if (t >= 0 && t <= 1) {
+					if ((x != segments[a][0].x || y != segments[a][0].y) && (x != segments[a][1].x || y != segments[a][1].y)) {
+						warn(segments, a, b, do_warn);
+						// splitting a
+						std::vector<point<T>> dv;
+						dv.push_back(point<T>(x, y));
+						dv.push_back(segments[a][1]);
+						segments.push_back(dv);
+						segments[a][1] = point<T>(x, y);
+						nexts.push_back(nexts[a]);
+						nexts[a] = nexts.size() - 1;
+						again = true;
+					}
+				}
+
+				if (s >= 0 && s <= 1) {
+					if ((x != segments[b][0].x || y != segments[b][0].y) && (x != segments[b][1].x || y != segments[b][1].y)) {
+						// splitting b
+						warn(segments, a, b, do_warn);
+						std::vector<point<T>> dv;
+						dv.push_back(point<T>(x, y));
+						dv.push_back(segments[b][1]);
+						segments.push_back(dv);
+						segments[b][1] = point<T>(x, y);
+						nexts.push_back(nexts[b]);
+						nexts[b] = nexts.size() - 1;
+						again = true;
+					}
+				}
+			}
+		}
+	}
+}
+
+template <typename T>
+void partition(std::vector<std::vector<point<T>>> &segs, std::vector<size_t> &subset, int direction, std::set<std::pair<size_t, size_t>> &possible) {
+	std::vector<T> points;
+
+	// List of X or Y midpoints of edges, so we can find the median
+
+	if (direction == 0) {
+		for (size_t i = 0; i < subset.size(); i++) {
+			points.push_back((segs[subset[i]][0].x + segs[subset[i]][1].x) / 2);
+		}
+	} else {
+		for (size_t i = 0; i < subset.size(); i++) {
+			points.push_back((segs[subset[i]][0].y + segs[subset[i]][1].y) / 2);
+		}
+	}
+
+	if (points.size() == 0) {
+		return;
+	}
+
+	size_t mid = points.size() / 2;
+	std::nth_element(points.begin(), points.begin() + mid, points.end());
+	T median = points[mid];
+
+	// Partition into sets that are above or below, or to the left or to the right of, the median.
+	// Segments that cross the median appear in both.
+
+	std::vector<size_t> one;
+	std::vector<size_t> two;
+
+	if (direction == 0) {
+		for (size_t i = 0; i < subset.size(); i++) {
+			if (segs[subset[i]][0].x <= median || segs[subset[i]][1].x <= median) {
+				one.push_back(subset[i]);
+			}
+			if (segs[subset[i]][0].x >= median || segs[subset[i]][1].x >= median) {
+				two.push_back(subset[i]);
+			}
+		}
+	} else {
+		for (size_t i = 0; i < subset.size(); i++) {
+			if (segs[subset[i]][0].y <= median || segs[subset[i]][1].y <= median) {
+				one.push_back(subset[i]);
+			}
+			if (segs[subset[i]][0].y >= median || segs[subset[i]][1].y >= median) {
+				two.push_back(subset[i]);
+			}
+		}
+	}
+
+	if (one.size() >= subset.size() || two.size() >= subset.size()) {
+		for (size_t i = 0; i < subset.size(); i++) {
+			for (size_t j = i + 1; j < subset.size(); j++) {
+				possible.insert(std::pair<size_t, size_t>(subset[i], subset[j]));
+			}
+		}
+	} else {
+		// By experiment, stopping at 10 is a little faster than either 5 or 20
+
+		if (one.size() < 10) {
+			for (size_t i = 0; i < one.size(); i++) {
+				for (size_t j = i + 1; j < one.size(); j++) {
+					possible.insert(std::pair<size_t, size_t>(one[i], one[j]));
+				}
+			}
+		} else {
+			partition(segs, one, !direction, possible);
+		}
+
+		if (two.size() < 10) {
+			for (size_t i = 0; i < two.size(); i++) {
+				for (size_t j = i + 1; j < two.size(); j++) {
+					possible.insert(std::pair<size_t, size_t>(two[i], two[j]));
+				}
+			}
+		} else {
+			partition(segs, two, !direction, possible);
+		}
+	}
+}
+
+template <typename T>
+std::vector<std::vector<point<T>>> intersect_segments(std::vector<std::vector<point<T>>> segments, std::vector<size_t> &nexts, bool do_warn, bool endpoint_ok) {
+	bool again = true;
+
+	while (again) {
+		again = false;
+
+		std::set<std::pair<size_t, size_t>> possible;
+
+		std::vector<size_t> subset;
+		for (size_t i = 0; i < segments.size(); i++) {
+			subset.push_back(i);
+		}
+
+		partition(segments, subset, 0, possible);
+
+		for (auto it = possible.begin(); it != possible.end(); ++it) {
+			check_intersection(segments, it->first, it->second, again, nexts, do_warn, endpoint_ok);
+		}
+	}
+
+	return segments;
+}
+
+template <typename T>
+linear_ring<T> remove_collinear(linear_ring<T> ring) {
+	linear_ring<T> out;
+
+	size_t len = ring.size() - 1;  // Exclude duplicated last point
+	for (size_t j = 0; j < len; j++) {
+		long long ccw =
+			ring[(j + len - 1) % len].x * ring[(j + len - 0) % len].y +
+			ring[(j + len - 0) % len].x * ring[(j + len + 1) % len].y +
+			ring[(j + len + 1) % len].x * ring[(j + len - 1) % len].y -
+			ring[(j + len - 1) % len].x * ring[(j + len + 1) % len].y -
+			ring[(j + len - 0) % len].x * ring[(j + len - 1) % len].y -
+			ring[(j + len + 1) % len].x * ring[(j + len - 0) % len].y;
+
+		if (ccw != 0) {
+			out.push_back(ring[j]);
+		}
+
+		if (ring.size() > 0 && ring[0] != ring[ring.size() - 1]) {
+			ring.push_back(ring[0]);
+		}
+	}
+
+	return out;
+}
+
+template <typename T>
+multi_polygon<T> snap_round(multi_polygon<T> geom, bool do_warn, bool endpoint_ok) {
+	std::vector<std::vector<point<T>>> segments;
+	std::vector<size_t> nexts;
+	std::vector<std::vector<size_t>> ring_starts;
+
+	// Crunch out any 0-length segments
+	for (size_t i = 0; i < geom.size(); i++) {
+		for (size_t j = 0; j < geom[i].size(); j++) {
+			for (ssize_t k = geom[i][j].size() - 1; k > 0; k--) {
+				if (geom[i][j][k] == geom[i][j][k - 1]) {
+					geom[i][j].erase(geom[i][j].begin() + k);
+				}
+			}
+		}
+	}
+
+	for (size_t i = 0; i < geom.size(); i++) {
+		ring_starts.push_back(std::vector<size_t>());
+
+		for (size_t j = 0; j < geom[i].size(); j++) {
+			size_t s = geom[i][j].size();
+
+			if (s > 1) {
+				ring_starts[i].push_back(segments.size());
+				size_t first = nexts.size();
+
+				for (size_t k = 0; k + 1 < s; k++) {
+					std::vector<point<T>> dv;
+					dv.push_back(geom[i][j][k]);
+					dv.push_back(geom[i][j][k + 1]);
+
+					segments.push_back(dv);
+					nexts.push_back(nexts.size() + 1);
+				}
+
+				// Fabricate a point if ring was not closed
+				if (geom[i][j][0] != geom[i][j][s - 1]) {
+					std::vector<point<T>> dv;
+					dv.push_back(geom[i][j][s - 1]);
+					dv.push_back(geom[i][j][0]);
+
+					segments.push_back(dv);
+					nexts.push_back(nexts.size() + 1);
+				}
+
+				// Last point of ring points back to first
+				nexts[nexts.size() - 1] = first;
+			}
+		}
+	}
+
+	segments = intersect_segments(segments, nexts, do_warn, endpoint_ok);
+
+	multi_polygon<T> mp;
+	for (size_t i = 0; i < ring_starts.size(); i++) {
+		mp.push_back(polygon<T>());
+
+		for (size_t j = 0; j < ring_starts[i].size(); j++) {
+			mp[i].push_back(linear_ring<T>());
+
+			size_t k = ring_starts[i][j];
+			do {
+				mp[i][j].push_back(segments[k][0]);
+				k = nexts[k];
+			} while (k != ring_starts[i][j]);
+
+			mp[i][j].push_back(segments[ring_starts[i][j]][0]);
+		}
+	}
+
+	return mp;
+}
+
+template <typename T>
+multi_line_string<T> snap_round(multi_line_string<T> geom, bool do_warn, bool endpoint_ok) {
+	std::vector<std::vector<point<T>>> segments;
+	std::vector<size_t> nexts;
+	std::vector<size_t> ring_starts;
+
+	// Crunch out any 0-length segments
+	for (size_t j = 0; j < geom.size(); j++) {
+		for (ssize_t k = geom[j].size() - 1; k > 0; k--) {
+			if (geom[j][k] == geom[j][k - 1]) {
+				geom[j].erase(geom[j].begin() + k);
+			}
+		}
+	}
+
+	for (size_t j = 0; j < geom.size(); j++) {
+		size_t s = geom[j].size();
+
+		if (s > 1) {
+			ring_starts.push_back(segments.size());
+			size_t first = nexts.size();
+
+			for (size_t k = 0; k + 1 < s; k++) {
+				std::vector<point<T>> dv;
+				dv.push_back(geom[j][k]);
+				dv.push_back(geom[j][k + 1]);
+
+				segments.push_back(dv);
+				nexts.push_back(nexts.size() + 1);
+			}
+
+			// Last point of ring points back to first
+			nexts[nexts.size() - 1] = first;
+		}
+	}
+
+	segments = intersect_segments(segments, nexts, do_warn, endpoint_ok);
+
+	multi_line_string<T> mp;
+	for (size_t j = 0; j < ring_starts.size(); j++) {
+		mp.push_back(line_string<T>());
+
+		size_t k = ring_starts[j];
+		size_t last = k;
+		do {
+			mp[j].push_back(segments[k][0]);
+			last = k;
+			k = nexts[k];
+		} while (k != ring_starts[j]);
+
+		mp[j].push_back(segments[last][1]);
+	}
+
+	return mp;
+}
+}
+}

mapbox/geometry/wagyu/active_bound_list.hpp

@@ -0,0 +1,425 @@
+#pragma once
+
+#ifdef DEBUG
+#include <iostream>
+#include <sstream>
+#endif
+
+#include <mapbox/geometry/wagyu/bound.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/local_minimum_util.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/scanbeam.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+using active_bound_list = std::list<bound_ptr<T>>;
+
+template <typename T>
+using active_bound_list_itr = typename active_bound_list<T>::iterator;
+
+template <typename T>
+using active_bound_list_rev_itr = typename active_bound_list<T>::reverse_iterator;
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const active_bound_list<T>& bnds) {
+    std::size_t c = 0;
+    for (auto const& bnd : bnds) {
+        out << "Index: " << c++ << std::endl;
+        out << *bnd;
+    }
+    return out;
+}
+
+template <typename T>
+std::string output_edges(active_bound_list<T> const& bnds) {
+    std::ostringstream out;
+    out << "[";
+    bool first = true;
+    for (auto const& bnd : bnds) {
+        if (first) {
+            first = false;
+        } else {
+            out << ",";
+        }
+        out << "[[" << bnd->current_edge->bot.x << "," << bnd->current_edge->bot.y << "],[";
+        out << bnd->current_edge->top.x << "," << bnd->current_edge->top.y << "]]";
+    }
+    out << "]";
+    return out.str();
+}
+
+#endif
+
+template <typename T>
+bool is_even_odd_fill_type(bound<T> const& bound,
+                           fill_type subject_fill_type,
+                           fill_type clip_fill_type) {
+    if (bound.poly_type == polygon_type_subject) {
+        return subject_fill_type == fill_type_even_odd;
+    } else {
+        return clip_fill_type == fill_type_even_odd;
+    }
+}
+
+template <typename T>
+bool is_even_odd_alt_fill_type(bound<T> const& bound,
+                               fill_type subject_fill_type,
+                               fill_type clip_fill_type) {
+    if (bound.poly_type == polygon_type_subject) {
+        return clip_fill_type == fill_type_even_odd;
+    } else {
+        return subject_fill_type == fill_type_even_odd;
+    }
+}
+
+template <typename T>
+inline bool bound2_inserts_before_bound1(bound<T> const& bound1, bound<T> const& bound2) {
+    if (values_are_equal(bound2.current_x, bound1.current_x)) {
+        if (bound2.current_edge->top.y > bound1.current_edge->top.y) {
+            return bound2.current_edge->top.x <
+                   get_current_x(*(bound1.current_edge), bound2.current_edge->top.y);
+        } else {
+            return bound1.current_edge->top.x >
+                   get_current_x(*(bound2.current_edge), bound1.current_edge->top.y);
+        }
+    } else {
+        return bound2.current_x < bound1.current_x;
+    }
+}
+
+template <typename T>
+active_bound_list_itr<T> insert_bound_into_ABL(bound<T>& bnd, active_bound_list<T>& active_bounds) {
+    auto itr = active_bounds.begin();
+    while (itr != active_bounds.end() && !bound2_inserts_before_bound1(*(*itr), bnd)) {
+        ++itr;
+    }
+    return active_bounds.insert(itr, &bnd);
+}
+
+template <typename T>
+active_bound_list_itr<T> insert_bound_into_ABL(bound<T>& bnd,
+                                               active_bound_list_itr<T> itr,
+                                               active_bound_list<T>& active_bounds) {
+    while (itr != active_bounds.end() && !bound2_inserts_before_bound1(*(*itr), bnd)) {
+        ++itr;
+    }
+    return active_bounds.insert(itr, &bnd);
+}
+
+template <typename T>
+inline bool is_maxima(bound<T>& bnd, T y) {
+    return bnd.next_edge == bnd.edges.end() && bnd.current_edge->top.y == y;
+}
+
+template <typename T>
+inline bool is_maxima(active_bound_list_itr<T>& bnd, T y) {
+    return is_maxima(*(*bnd), y);
+}
+
+template <typename T>
+inline bool is_intermediate(bound<T>& bnd, T y) {
+    return bnd.next_edge != bnd.edges.end() && bnd.current_edge->top.y == y;
+}
+
+template <typename T>
+inline bool is_intermediate(active_bound_list_itr<T>& bnd, T y) {
+    return is_intermediate(*(*bnd), y);
+}
+
+template <typename T>
+inline bool current_edge_is_horizontal(active_bound_list_itr<T>& bnd) {
+    return is_horizontal(*((*bnd)->current_edge));
+}
+
+template <typename T>
+inline bool next_edge_is_horizontal(active_bound_list_itr<T>& bnd) {
+    return is_horizontal(*((*bnd)->next_edge));
+}
+
+template <typename T>
+inline void swap_positions_in_ABL(active_bound_list_itr<T>& bnd1,
+                                  active_bound_list_itr<T>& bnd2,
+                                  active_bound_list<T>& active_bounds) {
+    if (std::next(bnd2) == bnd1) {
+        active_bounds.splice(bnd2, active_bounds, bnd1);
+    } else {
+        active_bounds.splice(bnd1, active_bounds, bnd2);
+    }
+}
+
+template <typename T>
+void next_edge_in_bound(active_bound_list_itr<T>& bnd, scanbeam_list<T>& scanbeam) {
+    ++((*bnd)->current_edge);
+    if ((*bnd)->current_edge != (*bnd)->edges.end()) {
+        ++((*bnd)->next_edge);
+        (*bnd)->current_x = static_cast<double>((*bnd)->current_edge->bot.x);
+        if (!current_edge_is_horizontal<T>(bnd)) {
+            scanbeam.push((*bnd)->current_edge->top.y);
+        }
+    }
+}
+
+template <typename T>
+active_bound_list_itr<T> get_maxima_pair(active_bound_list_itr<T> bnd,
+                                         active_bound_list<T>& active_bounds) {
+    auto bnd_itr = active_bounds.begin();
+    while (bnd_itr != active_bounds.end()) {
+        if (*bnd_itr == (*bnd)->maximum_bound) {
+            break;
+        }
+        ++bnd_itr;
+    }
+    return bnd_itr;
+}
+
+template <typename T>
+void set_winding_count(active_bound_list_itr<T>& bnd_itr,
+                       active_bound_list<T>& active_bounds,
+                       fill_type subject_fill_type,
+                       fill_type clip_fill_type) {
+
+    auto rev_bnd_itr = active_bound_list_rev_itr<T>(bnd_itr);
+    if (rev_bnd_itr == active_bounds.rend()) {
+        (*bnd_itr)->winding_count = (*bnd_itr)->winding_delta;
+        (*bnd_itr)->winding_count2 = 0;
+        return;
+    }
+
+    // find the edge of the same polytype that immediately preceeds 'edge' in
+    // AEL
+    while (rev_bnd_itr != active_bounds.rend() &&
+           (*rev_bnd_itr)->poly_type != (*bnd_itr)->poly_type) {
+        ++rev_bnd_itr;
+    }
+    if (rev_bnd_itr == active_bounds.rend()) {
+        (*bnd_itr)->winding_count = (*bnd_itr)->winding_delta;
+        (*bnd_itr)->winding_count2 = 0;
+    } else if (is_even_odd_fill_type(*(*bnd_itr), subject_fill_type, clip_fill_type)) {
+        // EvenOdd filling ...
+        (*bnd_itr)->winding_count = (*bnd_itr)->winding_delta;
+        (*bnd_itr)->winding_count2 = (*rev_bnd_itr)->winding_count2;
+    } else {
+        // nonZero, Positive or Negative filling ...
+        if ((*rev_bnd_itr)->winding_count * (*rev_bnd_itr)->winding_delta < 0) {
+            // prev edge is 'decreasing' WindCount (WC) toward zero
+            // so we're outside the previous polygon ...
+            if (std::abs(static_cast<int>((*rev_bnd_itr)->winding_count)) > 1) {
+                // outside prev poly but still inside another.
+                // when reversing direction of prev poly use the same WC
+                if ((*rev_bnd_itr)->winding_delta * (*bnd_itr)->winding_delta < 0) {
+                    (*bnd_itr)->winding_count = (*rev_bnd_itr)->winding_count;
+                } else {
+                    // otherwise continue to 'decrease' WC ...
+                    (*bnd_itr)->winding_count =
+                        (*rev_bnd_itr)->winding_count + (*bnd_itr)->winding_delta;
+                }
+            } else {
+                // now outside all polys of same polytype so set own WC ...
+                (*bnd_itr)->winding_count = (*bnd_itr)->winding_delta;
+            }
+        } else {
+            // prev edge is 'increasing' WindCount (WC) away from zero
+            // so we're inside the previous polygon ...
+            if ((*rev_bnd_itr)->winding_delta * (*bnd_itr)->winding_delta < 0) {
+                // if wind direction is reversing prev then use same WC
+                (*bnd_itr)->winding_count = (*rev_bnd_itr)->winding_count;
+            } else {
+                // otherwise add to WC ...
+                (*bnd_itr)->winding_count =
+                    (*rev_bnd_itr)->winding_count + (*bnd_itr)->winding_delta;
+            }
+        }
+        (*bnd_itr)->winding_count2 = (*rev_bnd_itr)->winding_count2;
+    }
+
+    // update winding_count2 ...
+    auto bnd_itr_forward = rev_bnd_itr.base();
+    if (is_even_odd_alt_fill_type(*(*bnd_itr), subject_fill_type, clip_fill_type)) {
+        // EvenOdd filling ...
+        while (bnd_itr_forward != bnd_itr) {
+            if ((*bnd_itr_forward)->winding_delta != 0) {
+                (*bnd_itr)->winding_count2 = ((*bnd_itr)->winding_count2 == 0 ? 1 : 0);
+            }
+            ++bnd_itr_forward;
+        }
+    } else {
+        // nonZero, Positive or Negative filling ...
+        while (bnd_itr_forward != bnd_itr) {
+            (*bnd_itr)->winding_count2 += (*bnd_itr_forward)->winding_delta;
+            ++bnd_itr_forward;
+        }
+    }
+}
+
+template <typename T>
+bool is_contributing(bound<T> const& bnd,
+                     clip_type cliptype,
+                     fill_type subject_fill_type,
+                     fill_type clip_fill_type) {
+    fill_type pft = subject_fill_type;
+    fill_type pft2 = clip_fill_type;
+    if (bnd.poly_type != polygon_type_subject) {
+        pft = clip_fill_type;
+        pft2 = subject_fill_type;
+    }
+
+    switch (pft) {
+    case fill_type_even_odd:
+        break;
+    case fill_type_non_zero:
+        if (std::abs(static_cast<int>(bnd.winding_count)) != 1) {
+            return false;
+        }
+        break;
+    case fill_type_positive:
+        if (bnd.winding_count != 1) {
+            return false;
+        }
+        break;
+    case fill_type_negative:
+    default:
+        if (bnd.winding_count != -1) {
+            return false;
+        }
+    }
+
+    switch (cliptype) {
+    case clip_type_intersection:
+        switch (pft2) {
+        case fill_type_even_odd:
+        case fill_type_non_zero:
+            return (bnd.winding_count2 != 0);
+        case fill_type_positive:
+            return (bnd.winding_count2 > 0);
+        case fill_type_negative:
+        default:
+            return (bnd.winding_count2 < 0);
+        }
+        break;
+    case clip_type_union:
+        switch (pft2) {
+        case fill_type_even_odd:
+        case fill_type_non_zero:
+            return (bnd.winding_count2 == 0);
+        case fill_type_positive:
+            return (bnd.winding_count2 <= 0);
+        case fill_type_negative:
+        default:
+            return (bnd.winding_count2 >= 0);
+        }
+        break;
+    case clip_type_difference:
+        if (bnd.poly_type == polygon_type_subject) {
+            switch (pft2) {
+            case fill_type_even_odd:
+            case fill_type_non_zero:
+                return (bnd.winding_count2 == 0);
+            case fill_type_positive:
+                return (bnd.winding_count2 <= 0);
+            case fill_type_negative:
+            default:
+                return (bnd.winding_count2 >= 0);
+            }
+        } else {
+            switch (pft2) {
+            case fill_type_even_odd:
+            case fill_type_non_zero:
+                return (bnd.winding_count2 != 0);
+            case fill_type_positive:
+                return (bnd.winding_count2 > 0);
+            case fill_type_negative:
+            default:
+                return (bnd.winding_count2 < 0);
+            }
+        }
+        break;
+    case clip_type_x_or:
+        return true;
+        break;
+    default:
+        return true;
+    }
+}
+
+template <typename T>
+void insert_lm_left_and_right_bound(bound<T>& left_bound,
+                                    bound<T>& right_bound,
+                                    active_bound_list<T>& active_bounds,
+                                    ring_manager<T>& rings,
+                                    scanbeam_list<T>& scanbeam,
+                                    clip_type cliptype,
+                                    fill_type subject_fill_type,
+                                    fill_type clip_fill_type) {
+
+    // Both left and right bound
+    auto lb_abl_itr = insert_bound_into_ABL(left_bound, active_bounds);
+    auto rb_abl_itr = active_bounds.insert(std::next(lb_abl_itr), &right_bound);
+    set_winding_count(lb_abl_itr, active_bounds, subject_fill_type, clip_fill_type);
+    (*rb_abl_itr)->winding_count = (*lb_abl_itr)->winding_count;
+    (*rb_abl_itr)->winding_count2 = (*lb_abl_itr)->winding_count2;
+    if (is_contributing(left_bound, cliptype, subject_fill_type, clip_fill_type)) {
+        add_local_minimum_point(lb_abl_itr, rb_abl_itr, active_bounds,
+                                (*lb_abl_itr)->current_edge->bot, rings);
+    }
+
+    // Add top of edges to scanbeam
+    scanbeam.push((*lb_abl_itr)->current_edge->top.y);
+
+    if (!current_edge_is_horizontal<T>(rb_abl_itr)) {
+        scanbeam.push((*rb_abl_itr)->current_edge->top.y);
+    }
+}
+
+template <typename T>
+void insert_local_minima_into_ABL(T const bot_y,
+                                  local_minimum_ptr_list<T> const& minima_sorted,
+                                  local_minimum_ptr_list_itr<T>& current_lm,
+                                  active_bound_list<T>& active_bounds,
+                                  ring_manager<T>& rings,
+                                  scanbeam_list<T>& scanbeam,
+                                  clip_type cliptype,
+                                  fill_type subject_fill_type,
+                                  fill_type clip_fill_type) {
+    while (current_lm != minima_sorted.end() && bot_y == (*current_lm)->y) {
+        initialize_lm<T>(current_lm);
+        auto& left_bound = (*current_lm)->left_bound;
+        auto& right_bound = (*current_lm)->right_bound;
+        insert_lm_left_and_right_bound(left_bound, right_bound, active_bounds, rings, scanbeam,
+                                       cliptype, subject_fill_type, clip_fill_type);
+        ++current_lm;
+    }
+}
+
+template <typename T>
+void insert_horizontal_local_minima_into_ABL(T const top_y,
+                                             local_minimum_ptr_list<T> const& minima_sorted,
+                                             local_minimum_ptr_list_itr<T>& current_lm,
+                                             active_bound_list<T>& active_bounds,
+                                             ring_manager<T>& rings,
+                                             scanbeam_list<T>& scanbeam,
+                                             clip_type cliptype,
+                                             fill_type subject_fill_type,
+                                             fill_type clip_fill_type) {
+    while (current_lm != minima_sorted.end() && top_y == (*current_lm)->y &&
+           (*current_lm)->minimum_has_horizontal) {
+        initialize_lm<T>(current_lm);
+        auto& left_bound = (*current_lm)->left_bound;
+        auto& right_bound = (*current_lm)->right_bound;
+        insert_lm_left_and_right_bound(left_bound, right_bound, active_bounds, rings, scanbeam,
+                                       cliptype, subject_fill_type, clip_fill_type);
+        ++current_lm;
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/bound.hpp

@@ -0,0 +1,95 @@
+#pragma once
+
+#include <list>
+
+#include <mapbox/geometry/point.hpp>
+
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+
+#ifdef DEBUG
+#include <iostream>
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct bound {
+
+    edge_list<T> edges;
+    edge_list_itr<T> current_edge;
+    edge_list_itr<T> next_edge;
+    mapbox::geometry::point<T> last_point;
+    ring_ptr<T> ring;
+    bound_ptr<T> maximum_bound; // the bound who's maximum connects with this bound
+    double current_x;
+    std::size_t pos;
+    std::int32_t winding_count;
+    std::int32_t winding_count2; // winding count of the opposite polytype
+    std::int8_t winding_delta;   // 1 or -1 depending on winding direction - 0 for linestrings
+    polygon_type poly_type;
+    edge_side side; // side only refers to current side of solution poly
+
+    bound() noexcept
+        : edges(),
+          current_edge(edges.end()),
+          last_point({ 0, 0 }),
+          ring(nullptr),
+          maximum_bound(nullptr),
+          current_x(0.0),
+          pos(0),
+          winding_count(0),
+          winding_count2(0),
+          winding_delta(0),
+          poly_type(polygon_type_subject),
+          side(edge_left) {
+    }
+
+    bound(bound<T>&& b) noexcept
+        : edges(std::move(b.edges)),
+          current_edge(std::move(b.current_edge)),
+          last_point(std::move(b.last_point)),
+          ring(std::move(b.ring)),
+          maximum_bound(std::move(b.maximum_bound)),
+          current_x(std::move(b.current_x)),
+          pos(std::move(b.pos)),
+          winding_count(std::move(b.winding_count)),
+          winding_count2(std::move(b.winding_count2)),
+          winding_delta(std::move(b.winding_delta)),
+          poly_type(std::move(b.poly_type)),
+          side(std::move(b.side)) {
+    }
+};
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const bound<T>& bnd) {
+    out << "    Bound: " << &bnd << std::endl;
+    out << "        current_x: " << bnd.current_x << std::endl;
+    out << "        last_point: " << bnd.last_point.x << ", " << bnd.last_point.y << std::endl;
+    out << *(bnd.current_edge);
+    out << "        winding count: " << bnd.winding_count << std::endl;
+    out << "        winding_count2: " << bnd.winding_count2 << std::endl;
+    out << "        winding_delta: " << static_cast<int>(bnd.winding_delta) << std::endl;
+    out << "        maximum_bound: " << bnd.maximum_bound << std::endl;
+    if (bnd.side == edge_left) {
+        out << "        side: left" << std::endl;
+    } else {
+        out << "        side: right" << std::endl;
+    }
+    out << "        ring: " << bnd.ring << std::endl;
+    if (bnd.ring) {
+        out << "        ring index: " << bnd.ring->ring_index << std::endl;
+    }
+    return out;
+}
+
+#endif
+}
+}
+}

mapbox/geometry/wagyu/build_edges.hpp

@@ -0,0 +1,181 @@
+#pragma once
+
+#include <mapbox/geometry/line_string.hpp>
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/polygon.hpp>
+
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+bool point_2_is_between_point_1_and_point_3(mapbox::geometry::point<T> const& pt1,
+                                            mapbox::geometry::point<T> const& pt2,
+                                            mapbox::geometry::point<T> const& pt3) {
+    if ((pt1 == pt3) || (pt1 == pt2) || (pt3 == pt2)) {
+        return false;
+    } else if (pt1.x != pt3.x) {
+        return (pt2.x > pt1.x) == (pt2.x < pt3.x);
+    } else {
+        return (pt2.y > pt1.y) == (pt2.y < pt3.y);
+    }
+}
+
+template <typename T>
+bool build_edge_list(mapbox::geometry::linear_ring<T> const& path_geometry, edge_list<T>& edges) {
+
+    if (path_geometry.size() < 3) {
+        return false;
+    }
+
+    // As this is a loop, we need to first go backwards from end to try and find
+    // the proper starting point for the iterators before the beginning
+
+    auto itr_rev = path_geometry.rbegin();
+    auto itr = path_geometry.begin();
+    mapbox::geometry::point<T> pt1 = *itr_rev;
+    mapbox::geometry::point<T> pt2 = *itr;
+
+    // Find next non repeated point going backwards from
+    // end for pt1
+    while (pt1 == pt2) {
+        ++itr_rev;
+        if (itr_rev == path_geometry.rend()) {
+            return false;
+        }
+        pt1 = *itr_rev;
+    }
+    ++itr;
+    mapbox::geometry::point<T> pt3 = *itr;
+    auto itr_last = itr_rev.base();
+    mapbox::geometry::point<T> front_pt;
+    mapbox::geometry::point<T> back_pt;
+    while (true) {
+        if (pt3 == pt2) {
+            // Duplicate point advance itr, but do not
+            // advance other points
+            if (itr == itr_last) {
+                break;
+            }
+            ++itr;
+            if (itr == itr_last) {
+                if (edges.empty()) {
+                    break;
+                }
+                pt3 = front_pt;
+            } else {
+                pt3 = *itr;
+            }
+            continue;
+        }
+
+        // Now check if slopes are equal between two segments - either
+        // a spike or a collinear point - if so drop point number 2.
+        if (slopes_equal(pt1, pt2, pt3)) {
+            // We need to reconsider previously added points
+            // because the point it was using was found to be collinear
+            // or a spike
+            pt2 = pt1;
+            if (!edges.empty()) {
+                edges.pop_back(); // remove previous edge (pt1)
+            }
+            if (!edges.empty()) {
+                if (back_pt == edges.back().top) {
+                    pt1 = edges.back().bot;
+                } else {
+                    pt1 = edges.back().top;
+                }
+                back_pt = pt1;
+            } else {
+                // If this occurs we must look to the back of the
+                // ring for new points.
+                while (*itr_rev == pt2) {
+                    ++itr_rev;
+                    if ((itr + 1) == itr_rev.base()) {
+                        return false;
+                    }
+                }
+                pt1 = *itr_rev;
+                itr_last = itr_rev.base();
+            }
+            continue;
+        }
+
+        if (edges.empty()) {
+            front_pt = pt2;
+        }
+        edges.emplace_back(pt2, pt3);
+        back_pt = pt2;
+        if (itr == itr_last) {
+            break;
+        }
+        pt1 = pt2;
+        pt2 = pt3;
+        ++itr;
+        if (itr == itr_last) {
+            if (edges.empty()) {
+                break;
+            }
+            pt3 = front_pt;
+        } else {
+            pt3 = *itr;
+        }
+    }
+
+    bool modified = false;
+    do {
+        modified = false;
+        if (edges.size() < 3) {
+            return false;
+        }
+        auto& f = edges.front();
+        auto& b = edges.back();
+        if (slopes_equal(f, b)) {
+            if (f.bot == b.top) {
+                if (f.top == b.bot) {
+                    edges.pop_back();
+                    edges.erase(edges.begin());
+                } else {
+                    f.bot = b.bot;
+                    edges.pop_back();
+                }
+                modified = true;
+            } else if (f.top == b.bot) {
+                f.top = b.top;
+                edges.pop_back();
+                modified = true;
+            } else if (f.top == b.top && f.bot == b.bot) {
+                edges.pop_back();
+                edges.erase(edges.begin());
+                modified = true;
+            } else if (f.top == b.top) {
+                if (point_2_is_between_point_1_and_point_3(f.top, f.bot, b.bot)) {
+                    b.top = f.bot;
+                    edges.erase(edges.begin());
+                } else {
+                    f.top = b.bot;
+                    edges.pop_back();
+                }
+                modified = true;
+            } else if (f.bot == b.bot) {
+                if (point_2_is_between_point_1_and_point_3(f.bot, f.top, b.top)) {
+                    b.bot = f.top;
+                    edges.erase(edges.begin());
+                } else {
+                    f.bot = b.top;
+                    edges.pop_back();
+                }
+                modified = true;
+            }
+        }
+    } while (modified);
+
+    return true;
+}
+}
+}
+}

mapbox/geometry/wagyu/build_local_minima_list.hpp

@@ -0,0 +1,39 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/build_edges.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/local_minimum_util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+bool add_line_string(mapbox::geometry::line_string<T> const& path_geometry,
+                     local_minimum_list<T>& minima_list) {
+    bool is_flat = true;
+    edge_list<T> new_edges;
+    new_edges.reserve(path_geometry.size());
+    if (!build_edge_list(path_geometry, new_edges, is_flat) || new_edges.empty()) {
+        return false;
+    }
+    add_line_to_local_minima_list(new_edges, minima_list, polygon_type_subject);
+    return true;
+}
+
+template <typename T>
+bool add_linear_ring(mapbox::geometry::linear_ring<T> const& path_geometry,
+                     local_minimum_list<T>& minima_list,
+                     polygon_type p_type) {
+    edge_list<T> new_edges;
+    new_edges.reserve(path_geometry.size());
+    if (!build_edge_list(path_geometry, new_edges) || new_edges.empty()) {
+        return false;
+    }
+    add_ring_to_local_minima_list(new_edges, minima_list, p_type);
+    return true;
+}
+}
+}
+}

mapbox/geometry/wagyu/build_result.hpp

@@ -0,0 +1,68 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/ring_util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+void push_ring_to_polygon(mapbox::geometry::polygon<T>& poly, ring_ptr<T>& r, bool reverse_output) {
+    mapbox::geometry::linear_ring<T> lr;
+    lr.reserve(r->size + 1);
+    auto firstPt = r->points;
+    auto ptIt = r->points;
+    if (reverse_output) {
+        do {
+            lr.emplace_back(ptIt->x, ptIt->y);
+            ptIt = ptIt->next;
+        } while (ptIt != firstPt);
+    } else {
+        do {
+            lr.emplace_back(ptIt->x, ptIt->y);
+            ptIt = ptIt->prev;
+        } while (ptIt != firstPt);
+    }
+    lr.emplace_back(firstPt->x, firstPt->y); // close the ring
+    poly.push_back(lr);
+}
+
+template <typename T>
+void build_result_polygons(std::vector<mapbox::geometry::polygon<T>>& solution,
+                           ring_list<T>& rings,
+                           bool reverse_output) {
+
+    for (auto& r : rings) {
+        assert(r->points);
+        std::size_t cnt = point_count(r->points);
+        if (cnt < 3) {
+            continue;
+        }
+        solution.emplace_back();
+        push_ring_to_polygon(solution.back(), r, reverse_output);
+        for (auto& c : r->children) {
+            assert(c->points);
+            cnt = point_count(c->points);
+            if (cnt < 3) {
+                continue;
+            }
+            push_ring_to_polygon(solution.back(), c, reverse_output);
+        }
+        for (auto& c : r->children) {
+            if (!c->children.empty()) {
+                build_result_polygons(solution, c->children, reverse_output);
+            }
+        }
+    }
+}
+
+template <typename T>
+void build_result(std::vector<mapbox::geometry::polygon<T>>& solution,
+                  ring_manager<T>& rings,
+                  bool reverse_output) {
+    build_result_polygons(solution, rings.children, reverse_output);
+}
+}
+}
+}

mapbox/geometry/wagyu/config.hpp

@@ -0,0 +1,53 @@
+#pragma once
+
+#include <cassert>
+#include <cstdint>
+#include <list>
+#include <stdexcept>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+enum clip_type : std::uint8_t {
+    clip_type_intersection = 0,
+    clip_type_union,
+    clip_type_difference,
+    clip_type_x_or
+};
+
+enum polygon_type : std::uint8_t { polygon_type_subject = 0, polygon_type_clip };
+
+enum fill_type : std::uint8_t {
+    fill_type_even_odd = 0,
+    fill_type_non_zero,
+    fill_type_positive,
+    fill_type_negative
+};
+
+static double const def_arc_tolerance = 0.25;
+
+static int const EDGE_UNASSIGNED = -1; // edge not currently 'owning' a solution
+static int const EDGE_SKIP = -2;       // edge that would otherwise close a path
+static std::int64_t const LOW_RANGE = 0x3FFFFFFF;
+static std::int64_t const HIGH_RANGE = 0x3FFFFFFFFFFFFFFFLL;
+
+enum horizontal_direction : std::uint8_t { right_to_left = 0, left_to_right = 1 };
+
+enum edge_side : std::uint8_t { edge_left = 0, edge_right };
+
+enum join_type : std::uint8_t { join_type_square = 0, join_type_round, join_type_miter };
+
+enum end_type {
+    end_type_closed_polygon = 0,
+    end_type_closed_line,
+    end_type_open_butt,
+    end_type_open_square,
+    end_type_open_round
+};
+
+template <typename T>
+using maxima_list = std::list<T>;
+}
+}
+}

mapbox/geometry/wagyu/edge.hpp

@@ -0,0 +1,120 @@
+#pragma once
+
+#include <cmath>
+#include <limits>
+#include <list>
+
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+#ifdef DEBUG
+#include <iostream>
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct bound;
+
+template <typename T>
+using bound_ptr = bound<T>*;
+
+template <typename T>
+struct edge {
+    mapbox::geometry::point<T> bot;
+    mapbox::geometry::point<T> top;
+    double dx;
+
+    edge(edge<T>&& e) noexcept : bot(std::move(e.bot)), top(std::move(e.top)), dx(std::move(e.dx)) {
+    }
+
+    edge& operator=(edge<T>&& e) noexcept {
+        bot = std::move(e.bot);
+        top = std::move(e.top);
+        dx = std::move(e.dx);
+        return *this;
+    }
+
+    edge(mapbox::geometry::point<T> const& current,
+         mapbox::geometry::point<T> const& next_pt) noexcept
+        : bot(current), top(current), dx(0.0) {
+        if (current.y >= next_pt.y) {
+            top = next_pt;
+        } else {
+            bot = next_pt;
+        }
+        double dy = static_cast<double>(top.y - bot.y);
+        if (value_is_zero(dy)) {
+            dx = std::numeric_limits<double>::infinity();
+        } else {
+            dx = static_cast<double>(top.x - bot.x) / dy;
+        }
+    }
+};
+
+template <typename T>
+using edge_ptr = edge<T>*;
+
+template <typename T>
+using edge_list = std::vector<edge<T>>;
+
+template <typename T>
+using edge_list_itr = typename edge_list<T>::iterator;
+
+template <typename T>
+bool slopes_equal(edge<T> const& e1, edge<T> const& e2) {
+    return (e1.top.y - e1.bot.y) * (e2.top.x - e2.bot.x) ==
+           (e1.top.x - e1.bot.x) * (e2.top.y - e2.bot.y);
+}
+
+template <typename T>
+inline bool is_horizontal(edge<T> const& e) {
+    return std::isinf(e.dx);
+}
+
+template <typename T>
+inline double get_current_x(edge<T> const& edge, const T current_y) {
+    if (current_y == edge.top.y) {
+        return static_cast<double>(edge.top.x);
+    } else {
+        return static_cast<double>(edge.bot.x) +
+               edge.dx * static_cast<double>(current_y - edge.bot.y);
+    }
+}
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const edge<T>& e) {
+    out << "    Edge: " << std::endl;
+    out << "        bot x: " << e.bot.x << " y: " << e.bot.y << std::endl;
+    out << "        top x: " << e.top.x << " y: " << e.top.y << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     edge_list<T> const& edges) {
+    out << "[";
+    bool first = true;
+    for (auto const& e : edges) {
+        if (first) {
+            first = false;
+        } else {
+            out << ",";
+        }
+        out << "[[" << e.bot.x << "," << e.bot.y << "],[";
+        out << e.top.x << "," << e.top.y << "]]";
+    }
+    out << "]";
+    return out;
+}
+
+#endif
+}
+}
+}

mapbox/geometry/wagyu/exceptions.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <stdexcept>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+class clipper_exception : public std::exception {
+private:
+    std::string m_descr;
+
+public:
+    clipper_exception(const char* description) : m_descr(description) {
+    }
+    virtual ~clipper_exception() noexcept {
+    }
+    virtual const char* what() const noexcept {
+        return m_descr.c_str();
+    }
+};
+}
+}
+}

mapbox/geometry/wagyu/intersect.hpp

@@ -0,0 +1,72 @@
+#pragma once
+
+#include <set>
+
+#include <mapbox/geometry/point.hpp>
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+
+#ifdef DEBUG
+#include <iostream>
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct intersect_node {
+
+    active_bound_list_itr<T> bound1;
+    active_bound_list_itr<T> bound2;
+    mapbox::geometry::point<double> pt;
+
+    intersect_node(intersect_node<T>&& n)
+        : bound1(std::move(n.bound1)), bound2(std::move(n.bound2)), pt(std::move(n.pt)) {
+    }
+
+    intersect_node& operator=(intersect_node<T>&& n) {
+        bound1 = std::move(n.bound1);
+        bound2 = std::move(n.bound2);
+        pt = std::move(n.pt);
+        return *this;
+    }
+
+    intersect_node(active_bound_list_itr<T> const& bound1_,
+                   active_bound_list_itr<T> const& bound2_,
+                   mapbox::geometry::point<double> const& pt_)
+        : bound1(bound1_), bound2(bound2_), pt(pt_) {
+    }
+};
+
+template <typename T>
+using intersect_list = std::vector<intersect_node<T>>;
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const intersect_node<T>& e) {
+    out << " point x: " << e.pt.x << " y: " << e.pt.y << std::endl;
+    out << " bound 1: " << std::endl;
+    out << *(*e.bound1) << std::endl;
+    out << " bound 2: " << std::endl;
+    out << *(*e.bound2) << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const intersect_list<T>& ints) {
+    std::size_t c = 0;
+    for (auto const& i : ints) {
+        out << "Intersection: " << c++ << std::endl;
+        out << i;
+    }
+    return out;
+}
+
+#endif
+}
+}
+}

mapbox/geometry/wagyu/intersect_util.hpp

@@ -0,0 +1,345 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+#include <mapbox/geometry/wagyu/bound.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/intersect.hpp>
+#include <mapbox/geometry/wagyu/ring_util.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct intersect_list_sorter {
+    inline bool operator()(intersect_node<T> const& node1, intersect_node<T> const& node2) {
+        if (!values_are_equal(node2.pt.y, node1.pt.y)) {
+            return node2.pt.y < node1.pt.y;
+        } else {
+            return ((*node2.bound1)->winding_count2 + (*node2.bound2)->winding_count2) >
+                   ((*node1.bound1)->winding_count2 + (*node1.bound2)->winding_count2);
+        }
+    }
+};
+
+template <typename T>
+inline mapbox::geometry::point<T> round_point(mapbox::geometry::point<double> const& pt) {
+    return mapbox::geometry::point<T>(round_towards_max<T>(pt.x), round_towards_max<T>(pt.y));
+}
+
+template <typename T>
+inline void swap_rings(bound<T>& b1, bound<T>& b2) {
+    ring_ptr<T> ring = b1.ring;
+    b1.ring = b2.ring;
+    b2.ring = ring;
+}
+
+template <typename T>
+inline void swap_sides(bound<T>& b1, bound<T>& b2) {
+    edge_side side = b1.side;
+    b1.side = b2.side;
+    b2.side = side;
+}
+
+template <typename T1, typename T2>
+bool get_edge_intersection(edge<T1> const& e1,
+                           edge<T1> const& e2,
+                           mapbox::geometry::point<T2>& pt) {
+    T2 p0_x = static_cast<T2>(e1.bot.x);
+    T2 p0_y = static_cast<T2>(e1.bot.y);
+    T2 p1_x = static_cast<T2>(e1.top.x);
+    T2 p1_y = static_cast<T2>(e1.top.y);
+    T2 p2_x = static_cast<T2>(e2.bot.x);
+    T2 p2_y = static_cast<T2>(e2.bot.y);
+    T2 p3_x = static_cast<T2>(e2.top.x);
+    T2 p3_y = static_cast<T2>(e2.top.y);
+    T2 s1_x, s1_y, s2_x, s2_y;
+    s1_x = p1_x - p0_x;
+    s1_y = p1_y - p0_y;
+    s2_x = p3_x - p2_x;
+    s2_y = p3_y - p2_y;
+
+    T2 s, t;
+    s = (-s1_y * (p0_x - p2_x) + s1_x * (p0_y - p2_y)) / (-s2_x * s1_y + s1_x * s2_y);
+    t = (s2_x * (p0_y - p2_y) - s2_y * (p0_x - p2_x)) / (-s2_x * s1_y + s1_x * s2_y);
+
+    if (s >= 0.0 && s <= 1.0 && t >= 0.0 && t <= 1.0) {
+        pt.x = p0_x + (t * s1_x);
+        pt.y = p0_y + (t * s1_y);
+        return true;
+    }
+    // LCOV_EXCL_START
+    return false;
+    // LCOV_EXCL_END
+}
+
+template <typename T>
+void build_intersect_list(active_bound_list<T>& active_bounds, intersect_list<T>& intersects) {
+    // bubblesort ...
+    bool isModified = false;
+    do {
+        isModified = false;
+        auto bnd = active_bounds.begin();
+        auto bnd_next = std::next(bnd);
+        while (bnd_next != active_bounds.end()) {
+            if ((*bnd)->current_x > (*bnd_next)->current_x &&
+                !slopes_equal(*((*bnd)->current_edge), *((*bnd_next)->current_edge))) {
+                mapbox::geometry::point<double> pt;
+                if (!get_edge_intersection<T, double>(*((*bnd)->current_edge),
+                                                      *((*bnd_next)->current_edge), pt)) {
+                    // LCOV_EXCL_START
+                    throw std::runtime_error(
+                        "Trying to find intersection of lines that do not intersect");
+                    // LCOV_EXCL_END
+                }
+                intersects.emplace_back(bnd, bnd_next, pt);
+                swap_positions_in_ABL(bnd, bnd_next, active_bounds);
+                bnd_next = std::next(bnd);
+                isModified = true;
+            } else {
+                bnd = bnd_next;
+                ++bnd_next;
+            }
+        }
+    } while (isModified);
+}
+
+template <typename T>
+void intersect_bounds(active_bound_list_itr<T>& b1,
+                      active_bound_list_itr<T>& b2,
+                      mapbox::geometry::point<T> const& pt,
+                      clip_type cliptype,
+                      fill_type subject_fill_type,
+                      fill_type clip_fill_type,
+                      ring_manager<T>& rings,
+                      active_bound_list<T>& active_bounds) {
+    bool b1Contributing = ((*b1)->ring != nullptr);
+    bool b2Contributing = ((*b2)->ring != nullptr);
+
+    // update winding counts...
+    // assumes that b1 will be to the Right of b2 ABOVE the intersection
+    if ((*b1)->poly_type == (*b2)->poly_type) {
+        if (is_even_odd_fill_type(*(*b1), subject_fill_type, clip_fill_type)) {
+            std::int32_t oldE1winding_count = (*b1)->winding_count;
+            (*b1)->winding_count = (*b2)->winding_count;
+            (*b2)->winding_count = oldE1winding_count;
+        } else {
+            if ((*b1)->winding_count + (*b2)->winding_delta == 0) {
+                (*b1)->winding_count = -(*b1)->winding_count;
+            } else {
+                (*b1)->winding_count += (*b2)->winding_delta;
+            }
+            if ((*b2)->winding_count - (*b1)->winding_delta == 0) {
+                (*b2)->winding_count = -(*b2)->winding_count;
+            } else {
+                (*b2)->winding_count -= (*b1)->winding_delta;
+            }
+        }
+    } else {
+        if (!is_even_odd_fill_type(*(*b2), subject_fill_type, clip_fill_type)) {
+            (*b1)->winding_count2 += (*b2)->winding_delta;
+        } else {
+            (*b1)->winding_count2 = ((*b1)->winding_count2 == 0) ? 1 : 0;
+        }
+        if (!is_even_odd_fill_type(*(*b1), subject_fill_type, clip_fill_type)) {
+            (*b2)->winding_count2 -= (*b1)->winding_delta;
+        } else {
+            (*b2)->winding_count2 = ((*b2)->winding_count2 == 0) ? 1 : 0;
+        }
+    }
+
+    fill_type b1FillType, b2FillType, b1FillType2, b2FillType2;
+    if ((*b1)->poly_type == polygon_type_subject) {
+        b1FillType = subject_fill_type;
+        b1FillType2 = clip_fill_type;
+    } else {
+        b1FillType = clip_fill_type;
+        b1FillType2 = subject_fill_type;
+    }
+    if ((*b2)->poly_type == polygon_type_subject) {
+        b2FillType = subject_fill_type;
+        b2FillType2 = clip_fill_type;
+    } else {
+        b2FillType = clip_fill_type;
+        b2FillType2 = subject_fill_type;
+    }
+
+    std::int32_t b1Wc, b2Wc;
+    switch (b1FillType) {
+    case fill_type_positive:
+        b1Wc = (*b1)->winding_count;
+        break;
+    case fill_type_negative:
+        b1Wc = -(*b1)->winding_count;
+        break;
+    case fill_type_even_odd:
+    case fill_type_non_zero:
+    default:
+        b1Wc = std::abs(static_cast<int>((*b1)->winding_count));
+    }
+    switch (b2FillType) {
+    case fill_type_positive:
+        b2Wc = (*b2)->winding_count;
+        break;
+    case fill_type_negative:
+        b2Wc = -(*b2)->winding_count;
+        break;
+    case fill_type_even_odd:
+    case fill_type_non_zero:
+    default:
+        b2Wc = std::abs(static_cast<int>((*b2)->winding_count));
+    }
+    if (b1Contributing && b2Contributing) {
+        if ((b1Wc != 0 && b1Wc != 1) || (b2Wc != 0 && b2Wc != 1) ||
+            ((*b1)->poly_type != (*b2)->poly_type && cliptype != clip_type_x_or)) {
+            add_local_maximum_point(b1, b2, pt, rings, active_bounds);
+        } else {
+            add_point(b1, active_bounds, pt, rings);
+            add_point(b2, active_bounds, pt, rings);
+            swap_sides(*(*b1), *(*b2));
+            swap_rings(*(*b1), *(*b2));
+        }
+    } else if (b1Contributing) {
+        if (b2Wc == 0 || b2Wc == 1) {
+            add_point(b1, active_bounds, pt, rings);
+            (*b2)->last_point = pt;
+            swap_sides(*(*b1), *(*b2));
+            swap_rings(*(*b1), *(*b2));
+        }
+    } else if (b2Contributing) {
+        if (b1Wc == 0 || b1Wc == 1) {
+            (*b1)->last_point = pt;
+            add_point(b2, active_bounds, pt, rings);
+            swap_sides(*(*b1), *(*b2));
+            swap_rings(*(*b1), *(*b2));
+        }
+    } else if ((b1Wc == 0 || b1Wc == 1) && (b2Wc == 0 || b2Wc == 1)) {
+        // neither bound is currently contributing ...
+
+        std::int32_t b1Wc2, b2Wc2;
+        switch (b1FillType2) {
+        case fill_type_positive:
+            b1Wc2 = (*b1)->winding_count2;
+            break;
+        case fill_type_negative:
+            b1Wc2 = -(*b1)->winding_count2;
+            break;
+        case fill_type_even_odd:
+        case fill_type_non_zero:
+        default:
+            b1Wc2 = std::abs(static_cast<int>((*b1)->winding_count2));
+        }
+        switch (b2FillType2) {
+        case fill_type_positive:
+            b2Wc2 = (*b2)->winding_count2;
+            break;
+        case fill_type_negative:
+            b2Wc2 = -(*b2)->winding_count2;
+            break;
+        case fill_type_even_odd:
+        case fill_type_non_zero:
+        default:
+            b2Wc2 = std::abs(static_cast<int>((*b2)->winding_count2));
+        }
+
+        if ((*b1)->poly_type != (*b2)->poly_type) {
+            add_local_minimum_point(b1, b2, active_bounds, pt, rings);
+        } else if (b1Wc == 1 && b2Wc == 1) {
+            switch (cliptype) {
+            case clip_type_intersection:
+                if (b1Wc2 > 0 && b2Wc2 > 0) {
+                    add_local_minimum_point(b1, b2, active_bounds, pt, rings);
+                }
+                break;
+            default:
+            case clip_type_union:
+                if (b1Wc2 <= 0 && b2Wc2 <= 0) {
+                    add_local_minimum_point(b1, b2, active_bounds, pt, rings);
+                }
+                break;
+            case clip_type_difference:
+                if ((((*b1)->poly_type == polygon_type_clip) && (b1Wc2 > 0) && (b2Wc2 > 0)) ||
+                    (((*b1)->poly_type == polygon_type_subject) && (b1Wc2 <= 0) && (b2Wc2 <= 0))) {
+                    add_local_minimum_point(b1, b2, active_bounds, pt, rings);
+                }
+                break;
+            case clip_type_x_or:
+                add_local_minimum_point(b1, b2, active_bounds, pt, rings);
+            }
+        } else {
+            swap_sides(*(*b1), *(*b2));
+        }
+    }
+}
+
+template <typename T>
+bool bounds_adjacent(intersect_node<T> const& inode) {
+    return (std::next(inode.bound1) == inode.bound2) || (std::next(inode.bound2) == inode.bound1);
+}
+
+template <typename T>
+void process_intersect_list(intersect_list<T>& intersects,
+                            clip_type cliptype,
+                            fill_type subject_fill_type,
+                            fill_type clip_fill_type,
+                            ring_manager<T>& rings,
+                            active_bound_list<T>& active_bounds) {
+    for (auto node_itr = intersects.begin(); node_itr != intersects.end(); ++node_itr) {
+        if (!bounds_adjacent(*node_itr)) {
+            auto next_itr = std::next(node_itr);
+            while (next_itr != intersects.end() && !bounds_adjacent(*next_itr)) {
+                ++next_itr;
+            }
+            if (next_itr == intersects.end()) {
+                throw std::runtime_error("Could not properly correct intersection order.");
+            }
+            std::iter_swap(node_itr, next_itr);
+        }
+        mapbox::geometry::point<T> pt = round_point<T>(node_itr->pt);
+        intersect_bounds(node_itr->bound1, node_itr->bound2, pt, cliptype, subject_fill_type,
+                         clip_fill_type, rings, active_bounds);
+        swap_positions_in_ABL(node_itr->bound1, node_itr->bound2, active_bounds);
+    }
+}
+
+template <typename T>
+void update_current_x(active_bound_list<T>& active_bounds, T top_y) {
+    std::size_t pos = 0;
+    for (auto& bnd : active_bounds) {
+        bnd->pos = pos++;
+        bnd->current_x = get_current_x(*bnd->current_edge, top_y);
+    }
+}
+
+template <typename T>
+void process_intersections(T top_y,
+                           active_bound_list<T>& active_bounds,
+                           clip_type cliptype,
+                           fill_type subject_fill_type,
+                           fill_type clip_fill_type,
+                           ring_manager<T>& rings) {
+    if (active_bounds.empty()) {
+        return;
+    }
+    update_current_x(active_bounds, top_y);
+    intersect_list<T> intersects;
+    build_intersect_list(active_bounds, intersects);
+
+    if (intersects.empty()) {
+        return;
+    }
+
+    // Restore order of active bounds list
+    active_bounds.sort(
+        [](bound_ptr<T> const& b1, bound_ptr<T> const& b2) { return b1->pos < b2->pos; });
+
+    // Sort the intersection list
+    std::stable_sort(intersects.begin(), intersects.end(), intersect_list_sorter<T>());
+
+    process_intersect_list(intersects, cliptype, subject_fill_type, clip_fill_type, rings,
+                           active_bounds);
+}
+}
+}
+}

mapbox/geometry/wagyu/local_minimum.hpp

@@ -0,0 +1,118 @@
+#pragma once
+
+#ifdef DEBUG
+#include <iostream>
+#include <sstream>
+#endif
+
+#include <queue>
+
+#include <mapbox/geometry/wagyu/bound.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct local_minimum {
+    bound<T> left_bound;
+    bound<T> right_bound;
+    T y;
+    bool minimum_has_horizontal;
+
+    local_minimum(bound<T>&& left_bound_, bound<T>&& right_bound_, T y_, bool has_horz_)
+        : left_bound(std::move(left_bound_)),
+          right_bound(std::move(right_bound_)),
+          y(y_),
+          minimum_has_horizontal(has_horz_) {
+    }
+};
+
+template <typename T>
+using local_minimum_list = std::deque<local_minimum<T>>;
+
+template <typename T>
+using local_minimum_itr = typename local_minimum_list<T>::iterator;
+
+template <typename T>
+using local_minimum_ptr = local_minimum<T>*;
+
+template <typename T>
+using local_minimum_ptr_list = std::vector<local_minimum_ptr<T>>;
+
+template <typename T>
+using local_minimum_ptr_list_itr = typename local_minimum_ptr_list<T>::iterator;
+
+template <typename T>
+struct local_minimum_sorter {
+    inline bool operator()(local_minimum_ptr<T> const& locMin1,
+                           local_minimum_ptr<T> const& locMin2) {
+        if (locMin2->y == locMin1->y) {
+            return locMin2->minimum_has_horizontal != locMin1->minimum_has_horizontal &&
+                   locMin1->minimum_has_horizontal;
+        }
+        return locMin2->y < locMin1->y;
+    }
+};
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const local_minimum<T>& lm) {
+    out << " Local Minimum:" << std::endl;
+    out << "    y: " << lm.y << std::endl;
+    if (lm.minimum_has_horizontal) {
+        out << "    minimum_has_horizontal: true" << std::endl;
+    } else {
+        out << "    minimum_has_horizontal: false" << std::endl;
+    }
+    out << "   left_bound: " << std::endl;
+    out << lm.left_bound << std::endl;
+    out << "   right_bound: " << std::endl;
+    out << lm.right_bound << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const local_minimum_ptr_list<T>& lms) {
+    for (auto const& lm : lms) {
+        out << *lm;
+    }
+    return out;
+}
+
+template <typename T>
+std::string output_all_edges(local_minimum_ptr_list<T> const& lms) {
+    std::ostringstream out;
+    out << "[";
+    bool first = true;
+    for (auto const& lm : lms) {
+        for (auto const& e : lm->left_bound.edges) {
+            if (first) {
+                first = false;
+            } else {
+                out << ",";
+            }
+            out << "[[" << e.bot.x << "," << e.bot.y << "],[";
+            out << e.top.x << "," << e.top.y << "]]";
+        }
+        for (auto const& e : lm->right_bound.edges) {
+            if (first) {
+                first = false;
+            } else {
+                out << ",";
+            }
+            out << "[[" << e.bot.x << "," << e.bot.y << "],[";
+            out << e.top.x << "," << e.top.y << "]]";
+        }
+    }
+    out << "]";
+    return out.str();
+}
+
+#endif
+}
+}
+}

mapbox/geometry/wagyu/local_minimum_util.hpp

@@ -0,0 +1,321 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+
+#ifdef DEBUG
+#include <stdexcept>
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+inline void reverse_horizontal(edge<T>& e) {
+    // swap horizontal edges' top and bottom x's so they follow the natural
+    // progression of the bounds - ie so their xbots will align with the
+    // adjoining lower edge. [Helpful in the process_horizontal() method.]
+    std::swap(e.top.x, e.bot.x);
+}
+
+// Make a list start on a local maximum by
+// shifting all the points not on a local maximum to the
+template <typename T>
+void start_list_on_local_maximum(edge_list<T>& edges) {
+    if (edges.size() <= 2) {
+        return;
+    }
+    // Find the first local maximum going forward in the list
+    auto prev_edge = edges.end();
+    --prev_edge;
+    bool prev_edge_is_horizontal = is_horizontal(*prev_edge);
+    auto edge = edges.begin();
+    bool edge_is_horizontal;
+    bool y_decreasing_before_last_horizontal = false; // assume false at start
+
+    while (edge != edges.end()) {
+        edge_is_horizontal = is_horizontal(*edge);
+        if ((!prev_edge_is_horizontal && !edge_is_horizontal && edge->top == prev_edge->top)) {
+            break;
+        }
+        if (!edge_is_horizontal && prev_edge_is_horizontal) {
+            if (y_decreasing_before_last_horizontal &&
+                (edge->top == prev_edge->bot || edge->top == prev_edge->top)) {
+                break;
+            }
+        } else if (!y_decreasing_before_last_horizontal && !prev_edge_is_horizontal &&
+                   edge_is_horizontal &&
+                   (prev_edge->top == edge->top || prev_edge->top == edge->bot)) {
+            y_decreasing_before_last_horizontal = true;
+        }
+        prev_edge_is_horizontal = edge_is_horizontal;
+        prev_edge = edge;
+        ++edge;
+    }
+    std::rotate(edges.begin(), edge, edges.end());
+}
+
+template <typename T>
+bound<T> create_bound_towards_minimum(edge_list<T>& edges) {
+    if (edges.size() == 1) {
+        if (is_horizontal(edges.front())) {
+            reverse_horizontal(edges.front());
+        }
+        bound<T> bnd;
+        std::swap(bnd.edges, edges);
+        return bnd;
+    }
+    auto next_edge = edges.begin();
+    auto edge = next_edge;
+    ++next_edge;
+    bool edge_is_horizontal = is_horizontal(*edge);
+    if (edge_is_horizontal) {
+        reverse_horizontal(*edge);
+    }
+    bool next_edge_is_horizontal;
+    bool y_increasing_before_last_horizontal = false; // assume false at start
+
+    while (next_edge != edges.end()) {
+        next_edge_is_horizontal = is_horizontal(*next_edge);
+        if ((!next_edge_is_horizontal && !edge_is_horizontal && edge->bot == next_edge->bot)) {
+            break;
+        }
+        if (!next_edge_is_horizontal && edge_is_horizontal) {
+            if (y_increasing_before_last_horizontal &&
+                (next_edge->bot == edge->bot || next_edge->bot == edge->top)) {
+                break;
+            }
+        } else if (!y_increasing_before_last_horizontal && !edge_is_horizontal &&
+                   next_edge_is_horizontal &&
+                   (edge->bot == next_edge->top || edge->bot == next_edge->bot)) {
+            y_increasing_before_last_horizontal = true;
+        }
+        edge_is_horizontal = next_edge_is_horizontal;
+        edge = next_edge;
+        if (edge_is_horizontal) {
+            reverse_horizontal(*edge);
+        }
+        ++next_edge;
+    }
+    bound<T> bnd;
+    if (next_edge == edges.end()) {
+        std::swap(edges, bnd.edges);
+    } else {
+        bnd.edges.reserve(std::distance(edges.begin(), next_edge));
+        std::move(edges.begin(), next_edge, std::back_inserter(bnd.edges));
+        edges.erase(edges.begin(), next_edge);
+    }
+    std::reverse(bnd.edges.begin(), bnd.edges.end());
+    return bnd;
+}
+
+template <typename T>
+bound<T> create_bound_towards_maximum(edge_list<T>& edges) {
+    if (edges.size() == 1) {
+        bound<T> bnd;
+        std::swap(bnd.edges, edges);
+        return bnd;
+    }
+    auto next_edge = edges.begin();
+    auto edge = next_edge;
+    ++next_edge;
+    bool edge_is_horizontal = is_horizontal(*edge);
+    bool next_edge_is_horizontal;
+    bool y_decreasing_before_last_horizontal = false; // assume false at start
+
+    while (next_edge != edges.end()) {
+        next_edge_is_horizontal = is_horizontal(*next_edge);
+        if ((!next_edge_is_horizontal && !edge_is_horizontal && edge->top == next_edge->top)) {
+            break;
+        }
+        if (!next_edge_is_horizontal && edge_is_horizontal) {
+            if (y_decreasing_before_last_horizontal &&
+                (next_edge->top == edge->bot || next_edge->top == edge->top)) {
+                break;
+            }
+        } else if (!y_decreasing_before_last_horizontal && !edge_is_horizontal &&
+                   next_edge_is_horizontal &&
+                   (edge->top == next_edge->top || edge->top == next_edge->bot)) {
+            y_decreasing_before_last_horizontal = true;
+        }
+        edge_is_horizontal = next_edge_is_horizontal;
+        edge = next_edge;
+        ++next_edge;
+    }
+    bound<T> bnd;
+    if (next_edge == edges.end()) {
+        std::swap(bnd.edges, edges);
+    } else {
+        bnd.edges.reserve(std::distance(edges.begin(), next_edge));
+        std::move(edges.begin(), next_edge, std::back_inserter(bnd.edges));
+        edges.erase(edges.begin(), next_edge);
+    }
+    return bnd;
+}
+
+template <typename T>
+void fix_horizontals(bound<T>& bnd) {
+
+    auto edge_itr = bnd.edges.begin();
+    auto next_itr = std::next(edge_itr);
+    if (next_itr == bnd.edges.end()) {
+        return;
+    }
+    if (is_horizontal(*edge_itr) && next_itr->bot != edge_itr->top) {
+        reverse_horizontal(*edge_itr);
+    }
+    auto prev_itr = edge_itr++;
+    while (edge_itr != bnd.edges.end()) {
+        if (is_horizontal(*edge_itr) && prev_itr->top != edge_itr->bot) {
+            reverse_horizontal(*edge_itr);
+        }
+        prev_itr = edge_itr;
+        ++edge_itr;
+    }
+}
+
+template <typename T>
+void move_horizontals_on_left_to_right(bound<T>& left_bound, bound<T>& right_bound) {
+    // We want all the horizontal segments that are at the same Y as the minimum to be on the right
+    // bound
+    auto edge_itr = left_bound.edges.begin();
+    while (edge_itr != left_bound.edges.end()) {
+        if (!is_horizontal(*edge_itr)) {
+            break;
+        }
+        reverse_horizontal(*edge_itr);
+        ++edge_itr;
+    }
+    if (edge_itr == left_bound.edges.begin()) {
+        return;
+    }
+    std::reverse(left_bound.edges.begin(), edge_itr);
+    auto dist = std::distance(left_bound.edges.begin(), edge_itr);
+    std::move(left_bound.edges.begin(), edge_itr, std::back_inserter(right_bound.edges));
+    left_bound.edges.erase(left_bound.edges.begin(), edge_itr);
+    std::rotate(right_bound.edges.begin(), std::prev(right_bound.edges.end(), dist),
+                right_bound.edges.end());
+}
+
+template <typename T>
+void add_ring_to_local_minima_list(edge_list<T>& edges,
+                                   local_minimum_list<T>& minima_list,
+                                   polygon_type poly_type) {
+
+    if (edges.empty()) {
+        return;
+    }
+    // Adjust the order of the ring so we start on a local maximum
+    // therefore we start right away on a bound.
+    start_list_on_local_maximum(edges);
+
+    bound_ptr<T> first_minimum = nullptr;
+    bound_ptr<T> last_maximum = nullptr;
+    while (!edges.empty()) {
+        bool lm_minimum_has_horizontal = false;
+        auto to_minimum = create_bound_towards_minimum(edges);
+        if (edges.empty()) {
+            throw std::runtime_error("Edges is empty after only creating a single bound.");
+        }
+        auto to_maximum = create_bound_towards_maximum(edges);
+        fix_horizontals(to_minimum);
+        fix_horizontals(to_maximum);
+        auto to_max_first_non_horizontal = to_maximum.edges.begin();
+        auto to_min_first_non_horizontal = to_minimum.edges.begin();
+        bool minimum_is_left = true;
+        while (to_max_first_non_horizontal != to_maximum.edges.end() &&
+               is_horizontal(*to_max_first_non_horizontal)) {
+            lm_minimum_has_horizontal = true;
+            ++to_max_first_non_horizontal;
+        }
+        while (to_min_first_non_horizontal != to_minimum.edges.end() &&
+               is_horizontal(*to_min_first_non_horizontal)) {
+            lm_minimum_has_horizontal = true;
+            ++to_min_first_non_horizontal;
+        }
+#ifdef DEBUG
+        if (to_max_first_non_horizontal == to_maximum.edges.end() ||
+            to_min_first_non_horizontal == to_minimum.edges.end()) {
+            throw std::runtime_error("should not have a horizontal only bound for a ring");
+        }
+#endif
+        if (lm_minimum_has_horizontal) {
+            if (to_max_first_non_horizontal->bot.x > to_min_first_non_horizontal->bot.x) {
+                minimum_is_left = true;
+                move_horizontals_on_left_to_right(to_minimum, to_maximum);
+            } else {
+                minimum_is_left = false;
+                move_horizontals_on_left_to_right(to_maximum, to_minimum);
+            }
+        } else {
+            if (to_max_first_non_horizontal->dx > to_min_first_non_horizontal->dx) {
+                minimum_is_left = false;
+            } else {
+                minimum_is_left = true;
+            }
+        }
+        assert(!to_minimum.edges.empty());
+        assert(!to_maximum.edges.empty());
+        auto const& min_front = to_minimum.edges.front();
+        if (last_maximum) {
+            to_minimum.maximum_bound = last_maximum;
+        }
+        to_minimum.poly_type = poly_type;
+        to_maximum.poly_type = poly_type;
+        if (!minimum_is_left) {
+            to_minimum.side = edge_right;
+            to_maximum.side = edge_left;
+            to_minimum.winding_delta = -1;
+            to_maximum.winding_delta = 1;
+            minima_list.emplace_back(std::move(to_maximum), std::move(to_minimum), min_front.bot.y,
+                                     lm_minimum_has_horizontal);
+            if (!last_maximum) {
+                first_minimum = &(minima_list.back().right_bound);
+            } else {
+                last_maximum->maximum_bound = &(minima_list.back().right_bound);
+            }
+            last_maximum = &(minima_list.back().left_bound);
+        } else {
+            to_minimum.side = edge_left;
+            to_maximum.side = edge_right;
+            to_minimum.winding_delta = -1;
+            to_maximum.winding_delta = 1;
+            minima_list.emplace_back(std::move(to_minimum), std::move(to_maximum), min_front.bot.y,
+                                     lm_minimum_has_horizontal);
+            if (!last_maximum) {
+                first_minimum = &(minima_list.back().left_bound);
+            } else {
+                last_maximum->maximum_bound = &(minima_list.back().left_bound);
+            }
+            last_maximum = &(minima_list.back().right_bound);
+        }
+    }
+    last_maximum->maximum_bound = first_minimum;
+    first_minimum->maximum_bound = last_maximum;
+}
+
+template <typename T>
+void initialize_lm(local_minimum_ptr_list_itr<T>& lm) {
+    if (!(*lm)->left_bound.edges.empty()) {
+        (*lm)->left_bound.current_edge = (*lm)->left_bound.edges.begin();
+        (*lm)->left_bound.next_edge = std::next((*lm)->left_bound.current_edge);
+        (*lm)->left_bound.current_x = static_cast<double>((*lm)->left_bound.current_edge->bot.x);
+        (*lm)->left_bound.winding_count = 0;
+        (*lm)->left_bound.winding_count2 = 0;
+        (*lm)->left_bound.side = edge_left;
+        (*lm)->left_bound.ring = nullptr;
+    }
+    if (!(*lm)->right_bound.edges.empty()) {
+        (*lm)->right_bound.current_edge = (*lm)->right_bound.edges.begin();
+        (*lm)->right_bound.next_edge = std::next((*lm)->right_bound.current_edge);
+        (*lm)->right_bound.current_x = static_cast<double>((*lm)->right_bound.current_edge->bot.x);
+        (*lm)->right_bound.winding_count = 0;
+        (*lm)->right_bound.winding_count2 = 0;
+        (*lm)->right_bound.side = edge_right;
+        (*lm)->right_bound.ring = nullptr;
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/point.hpp

@@ -0,0 +1,111 @@
+#pragma once
+
+#include <mapbox/geometry/point.hpp>
+
+#ifdef DEBUG
+#include <iostream>
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+struct point;
+
+template <typename T>
+using point_ptr = point<T>*;
+
+template <typename T>
+using const_point_ptr = point<T>* const;
+
+template <typename T>
+struct ring;
+
+template <typename T>
+using ring_ptr = ring<T>*;
+
+template <typename T>
+using const_ring_ptr = ring<T>* const;
+
+template <typename T>
+struct point {
+    using coordinate_type = T;
+    ring_ptr<T> ring;
+    T x;
+    T y;
+    point_ptr<T> next;
+    point_ptr<T> prev;
+
+    point(point<T>&& p)
+        : ring(std::move(p.ring)),
+          x(std::move(p.x)),
+          y(std::move(p.y)),
+          next(std::move(p.next)),
+          prev(std::move(p.prev)) {
+    }
+
+    point() : ring(nullptr), x(0), y(0), prev(this), next(this) {
+    }
+    point(T x_, T y_) : ring(nullptr), x(x_), y(y_), next(this), prev(this) {
+    }
+    point(ring_ptr<T> ring_, mapbox::geometry::point<T> const& pt)
+        : ring(ring_), x(pt.x), y(pt.y), next(this), prev(this) {
+    }
+
+    point(ring_ptr<T> ring_, mapbox::geometry::point<T> const& pt, point_ptr<T> before_this_point)
+        : ring(ring_), x(pt.x), y(pt.y), next(before_this_point), prev(before_this_point->prev) {
+        before_this_point->prev = this;
+        prev->next = this;
+    }
+};
+
+template <typename T>
+bool operator==(point<T> const& lhs, point<T> const& rhs) {
+    return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+
+template <typename T>
+bool operator==(mapbox::geometry::point<T> const& lhs, point<T> const& rhs) {
+    return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+
+template <typename T>
+bool operator==(point<T> const& lhs, mapbox::geometry::point<T> const& rhs) {
+    return lhs.x == rhs.x && lhs.y == rhs.y;
+}
+
+template <typename T>
+bool operator!=(point<T> const& lhs, point<T> const& rhs) {
+    return lhs.x != rhs.x || lhs.y != rhs.y;
+}
+
+template <typename T>
+bool operator!=(mapbox::geometry::point<T> const& lhs, point<T> const& rhs) {
+    return lhs.x != rhs.x || lhs.y != rhs.y;
+}
+
+template <typename T>
+bool operator!=(point<T> const& lhs, mapbox::geometry::point<T> const& rhs) {
+    return lhs.x != rhs.x || lhs.y != rhs.y;
+}
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const point<T>& p) {
+    out << "  point at: " << p.x << ", " << p.y;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const mapbox::geometry::point<T>& p) {
+    out << "  point at: " << p.x << ", " << p.y;
+    return out;
+}
+#endif
+}
+}
+}

mapbox/geometry/wagyu/process_horizontal.hpp

@@ -0,0 +1,273 @@
+#pragma once
+
+#include <mapbox/geometry/line_string.hpp>
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/polygon.hpp>
+
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+active_bound_list_itr<T> process_horizontal_left_to_right(T scanline_y,
+                                                          active_bound_list_itr<T>& horz_bound,
+                                                          active_bound_list<T>& active_bounds,
+                                                          ring_manager<T>& rings,
+                                                          scanbeam_list<T>& scanbeam,
+                                                          clip_type cliptype,
+                                                          fill_type subject_fill_type,
+                                                          fill_type clip_fill_type) {
+    auto horizontal_itr_behind = horz_bound;
+    bool is_maxima_edge = is_maxima(horz_bound, scanline_y);
+    auto bound_max_pair = active_bounds.end();
+    if (is_maxima_edge) {
+        bound_max_pair = get_maxima_pair<T>(horz_bound, active_bounds);
+    }
+
+    auto hp_itr = rings.current_hp_itr;
+    while (hp_itr != rings.hot_pixels.end() &&
+           (hp_itr->y > scanline_y ||
+            (hp_itr->y == scanline_y && hp_itr->x < (*horz_bound)->current_edge->bot.x))) {
+        ++hp_itr;
+    }
+
+    auto bnd = std::next(horz_bound);
+
+    while (bnd != active_bounds.end()) {
+        // this code block inserts extra coords into horizontal edges (in output
+        // polygons) wherever hot pixels touch these horizontal edges. This helps
+        //'simplifying' polygons (ie if the Simplify property is set).
+        while (hp_itr != rings.hot_pixels.end() && hp_itr->y == scanline_y &&
+               hp_itr->x < std::llround((*bnd)->current_x) &&
+               hp_itr->x < (*horz_bound)->current_edge->top.x) {
+            if ((*horz_bound)->ring) {
+                add_point_to_ring(*(*horz_bound), *hp_itr, rings);
+            }
+            ++hp_itr;
+        }
+
+        if ((*bnd)->current_x > static_cast<double>((*horz_bound)->current_edge->top.x)) {
+            break;
+        }
+
+        // Also break if we've got to the end of an intermediate horizontal edge ...
+        // nb: Smaller Dx's are to the right of larger Dx's ABOVE the horizontal.
+        if (std::llround((*bnd)->current_x) == (*horz_bound)->current_edge->top.x &&
+            (*horz_bound)->next_edge != (*horz_bound)->edges.end() &&
+            (*horz_bound)->current_edge->dx < (*horz_bound)->next_edge->dx) {
+            break;
+        }
+
+        // note: may be done multiple times
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(
+                *(*horz_bound),
+                mapbox::geometry::point<T>(std::llround((*bnd)->current_x), scanline_y), rings);
+        }
+
+        // OK, so far we're still in range of the horizontal Edge  but make sure
+        // we're at the last of consec. horizontals when matching with eMaxPair
+        if (is_maxima_edge && bnd == bound_max_pair) {
+            if ((*horz_bound)->ring) {
+                add_local_maximum_point(horz_bound, bound_max_pair,
+                                        (*horz_bound)->current_edge->top, rings, active_bounds);
+            }
+            active_bounds.erase(bound_max_pair);
+            auto after_horz = active_bounds.erase(horz_bound);
+            if (horizontal_itr_behind != horz_bound) {
+                return horizontal_itr_behind;
+            } else {
+                return after_horz;
+            }
+        }
+
+        intersect_bounds(horz_bound, bnd,
+                         mapbox::geometry::point<T>(std::llround((*bnd)->current_x), scanline_y),
+                         cliptype, subject_fill_type, clip_fill_type, rings, active_bounds);
+        auto next_bnd = std::next(bnd);
+        swap_positions_in_ABL(horz_bound, bnd, active_bounds);
+        if (current_edge_is_horizontal<T>(bnd) && horizontal_itr_behind == horz_bound) {
+            horizontal_itr_behind = bnd;
+        }
+        bnd = next_bnd;
+    } // end while (bnd != active_bounds.end())
+
+    if ((*horz_bound)->ring) {
+        while (hp_itr != rings.hot_pixels.end() && hp_itr->y == scanline_y &&
+               hp_itr->x < std::llround((*horz_bound)->current_edge->top.x)) {
+            add_point_to_ring(*(*horz_bound), *hp_itr, rings);
+            ++hp_itr;
+        }
+    }
+
+    if ((*horz_bound)->next_edge != (*horz_bound)->edges.end()) {
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(*(*horz_bound), (*horz_bound)->current_edge->top, rings);
+            next_edge_in_bound(horz_bound, scanbeam);
+        } else {
+            next_edge_in_bound(horz_bound, scanbeam);
+        }
+        if (horizontal_itr_behind != horz_bound) {
+            return horizontal_itr_behind;
+        } else {
+            return std::next(horz_bound);
+        }
+    } else {
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(*(*horz_bound), (*horz_bound)->current_edge->top, rings);
+        }
+        auto after_horz = active_bounds.erase(horz_bound);
+        if (horizontal_itr_behind != horz_bound) {
+            return horizontal_itr_behind;
+        } else {
+            return after_horz;
+        }
+    }
+}
+
+template <typename T>
+active_bound_list_itr<T> process_horizontal_right_to_left(T scanline_y,
+                                                          active_bound_list_itr<T>& horz_bound,
+                                                          active_bound_list<T>& active_bounds,
+                                                          ring_manager<T>& rings,
+                                                          scanbeam_list<T>& scanbeam,
+                                                          clip_type cliptype,
+                                                          fill_type subject_fill_type,
+                                                          fill_type clip_fill_type) {
+    bool is_maxima_edge = is_maxima(horz_bound, scanline_y);
+    auto bound_max_pair = active_bounds.end();
+    if (is_maxima_edge) {
+        bound_max_pair = get_maxima_pair<T>(horz_bound, active_bounds);
+    }
+    auto hp_itr_fwd = rings.current_hp_itr;
+    while (hp_itr_fwd != rings.hot_pixels.end() &&
+           (hp_itr_fwd->y < scanline_y ||
+            (hp_itr_fwd->y == scanline_y && hp_itr_fwd->x < (*horz_bound)->current_edge->top.x))) {
+        ++hp_itr_fwd;
+    }
+    auto hp_itr = hot_pixel_rev_itr<T>(hp_itr_fwd);
+
+    auto bnd = active_bound_list_rev_itr<T>(horz_bound);
+    while (bnd != active_bounds.rend()) {
+        // this code block inserts extra coords into horizontal edges (in output
+        // polygons) wherever hot pixels touch these horizontal edges.
+        while (hp_itr != rings.hot_pixels.rend() && hp_itr->y == scanline_y &&
+               hp_itr->x > std::llround((*bnd)->current_x) &&
+               hp_itr->x > (*horz_bound)->current_edge->top.x) {
+            if ((*horz_bound)->ring) {
+                add_point_to_ring(*(*horz_bound), *hp_itr, rings);
+            }
+            ++hp_itr;
+        }
+
+        if ((*bnd)->current_x < static_cast<double>((*horz_bound)->current_edge->top.x)) {
+            break;
+        }
+
+        // Also break if we've got to the end of an intermediate horizontal edge ...
+        // nb: Smaller Dx's are to the right of larger Dx's ABOVE the horizontal.
+        if (std::llround((*bnd)->current_x) == (*horz_bound)->current_edge->top.x &&
+            (*horz_bound)->next_edge != (*horz_bound)->edges.end() &&
+            (*horz_bound)->current_edge->dx < (*horz_bound)->next_edge->dx) {
+            break;
+        }
+
+        // note: may be done multiple times
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(
+                *(*horz_bound),
+                mapbox::geometry::point<T>(std::llround((*bnd)->current_x), scanline_y), rings);
+        }
+        auto bnd_forward = --(bnd.base());
+
+        // OK, so far we're still in range of the horizontal Edge  but make sure
+        // we're at the last of consec. horizontals when matching with eMaxPair
+        if (is_maxima_edge && bnd_forward == bound_max_pair) {
+            if ((*horz_bound)->ring) {
+                add_local_maximum_point(horz_bound, bound_max_pair,
+                                        (*horz_bound)->current_edge->top, rings, active_bounds);
+            }
+            active_bounds.erase(bound_max_pair);
+            return active_bounds.erase(horz_bound);
+        }
+
+        intersect_bounds(bnd_forward, horz_bound,
+                         mapbox::geometry::point<T>(std::llround((*bnd)->current_x), scanline_y),
+                         cliptype, subject_fill_type, clip_fill_type, rings, active_bounds);
+        swap_positions_in_ABL(horz_bound, bnd_forward, active_bounds);
+        // Why are we not incrementing the bnd iterator here:
+        // It is because reverse iterators point to a `base()` iterator that is a forward
+        // iterator that is one ahead of the reverse bound. This will always be the horizontal
+        // bound,
+        // so what the reverse bound points to will have changed.
+    } // end while (bnd != active_bounds.rend())
+
+    if ((*horz_bound)->ring) {
+        while (hp_itr != rings.hot_pixels.rend() && hp_itr->y == scanline_y &&
+               hp_itr->x > (*horz_bound)->current_edge->top.x) {
+            add_point_to_ring(*(*horz_bound), *hp_itr, rings);
+            ++hp_itr;
+        }
+    }
+
+    if ((*horz_bound)->next_edge != (*horz_bound)->edges.end()) {
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(*(*horz_bound), (*horz_bound)->current_edge->top, rings);
+            next_edge_in_bound(horz_bound, scanbeam);
+        } else {
+            next_edge_in_bound(horz_bound, scanbeam);
+        }
+        return std::next(horz_bound);
+    } else {
+        if ((*horz_bound)->ring) {
+            add_point_to_ring(*(*horz_bound), (*horz_bound)->current_edge->top, rings);
+        }
+        return active_bounds.erase(horz_bound);
+    }
+}
+
+template <typename T>
+active_bound_list_itr<T> process_horizontal(T scanline_y,
+                                            active_bound_list_itr<T>& horz_bound,
+                                            active_bound_list<T>& active_bounds,
+                                            ring_manager<T>& rings,
+                                            scanbeam_list<T>& scanbeam,
+                                            clip_type cliptype,
+                                            fill_type subject_fill_type,
+                                            fill_type clip_fill_type) {
+    if ((*horz_bound)->current_edge->bot.x < (*horz_bound)->current_edge->top.x) {
+        return process_horizontal_left_to_right(scanline_y, horz_bound, active_bounds, rings,
+                                                scanbeam, cliptype, subject_fill_type,
+                                                clip_fill_type);
+    } else {
+        return process_horizontal_right_to_left(scanline_y, horz_bound, active_bounds, rings,
+                                                scanbeam, cliptype, subject_fill_type,
+                                                clip_fill_type);
+    }
+}
+
+template <typename T>
+void process_horizontals(T scanline_y,
+                         active_bound_list<T>& active_bounds,
+                         ring_manager<T>& rings,
+                         scanbeam_list<T>& scanbeam,
+                         clip_type cliptype,
+                         fill_type subject_fill_type,
+                         fill_type clip_fill_type) {
+    for (auto bnd_itr = active_bounds.begin(); bnd_itr != active_bounds.end();) {
+        if (current_edge_is_horizontal<T>(bnd_itr)) {
+            bnd_itr = process_horizontal(scanline_y, bnd_itr, active_bounds, rings, scanbeam,
+                                         cliptype, subject_fill_type, clip_fill_type);
+        } else {
+            ++bnd_itr;
+        }
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/process_maxima.hpp

@@ -0,0 +1,125 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/intersect_util.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/local_minimum_util.hpp>
+#include <mapbox/geometry/wagyu/process_horizontal.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/ring_util.hpp>
+#include <mapbox/geometry/wagyu/topology_correction.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+active_bound_list_itr<T> do_maxima(active_bound_list_itr<T>& bnd,
+                                   active_bound_list_itr<T>& bndMaxPair,
+                                   clip_type cliptype,
+                                   fill_type subject_fill_type,
+                                   fill_type clip_fill_type,
+                                   ring_manager<T>& rings,
+                                   active_bound_list<T>& active_bounds) {
+    if (bndMaxPair == active_bounds.end()) {
+        if ((*bnd)->ring) {
+            add_point_to_ring(*(*bnd), (*bnd)->current_edge->top, rings);
+        }
+        return active_bounds.erase(bnd);
+    }
+    auto bnd_next = std::next(bnd);
+    auto return_bnd = bnd_next;
+    bool skipped = false;
+    while (bnd_next != active_bounds.end() && bnd_next != bndMaxPair) {
+        skipped = true;
+        intersect_bounds(bnd, bnd_next, (*bnd)->current_edge->top, cliptype, subject_fill_type,
+                         clip_fill_type, rings, active_bounds);
+        swap_positions_in_ABL(bnd, bnd_next, active_bounds);
+        bnd_next = std::next(bnd);
+    }
+
+    if (!(*bnd)->ring && !(*bndMaxPair)->ring) {
+        active_bounds.erase(bndMaxPair);
+    } else if ((*bnd)->ring && (*bndMaxPair)->ring) {
+        add_local_maximum_point(bnd, bndMaxPair, (*bnd)->current_edge->top, rings, active_bounds);
+        active_bounds.erase(bndMaxPair);
+    } else {
+        throw std::runtime_error("DoMaxima error");
+    }
+    auto prev_itr = active_bounds.erase(bnd);
+    if (skipped) {
+        return return_bnd;
+    } else {
+        return prev_itr;
+    }
+}
+
+template <typename T>
+void process_edges_at_top_of_scanbeam(T top_y,
+                                      active_bound_list<T>& active_bounds,
+                                      scanbeam_list<T>& scanbeam,
+                                      local_minimum_ptr_list<T> const& minima_sorted,
+                                      local_minimum_ptr_list_itr<T>& current_lm,
+                                      ring_manager<T>& rings,
+                                      clip_type cliptype,
+                                      fill_type subject_fill_type,
+                                      fill_type clip_fill_type) {
+
+    for (auto bnd = active_bounds.begin(); bnd != active_bounds.end();) {
+        // 1. Process maxima, treating them as if they are "bent" horizontal edges,
+        // but exclude maxima with horizontal edges.
+
+        bool is_maxima_edge = is_maxima(bnd, top_y);
+
+        if (is_maxima_edge) {
+            auto bnd_max_pair = get_maxima_pair(bnd, active_bounds);
+            is_maxima_edge = ((bnd_max_pair == active_bounds.end() ||
+                               !current_edge_is_horizontal<T>(bnd_max_pair)) &&
+                              is_maxima(bnd_max_pair, top_y));
+            if (is_maxima_edge) {
+                bnd = do_maxima(bnd, bnd_max_pair, cliptype, subject_fill_type, clip_fill_type,
+                                rings, active_bounds);
+                continue;
+            }
+        }
+
+        // 2. Promote horizontal edges.
+        if (is_intermediate(bnd, top_y) && next_edge_is_horizontal<T>(bnd)) {
+            if ((*bnd)->ring) {
+                insert_hot_pixels_in_path(*(*bnd), (*bnd)->current_edge->top, rings, false);
+            }
+            next_edge_in_bound(bnd, scanbeam);
+            if ((*bnd)->ring) {
+                add_point_to_ring(*(*bnd), (*bnd)->current_edge->bot, rings);
+            }
+        } else {
+            (*bnd)->current_x = get_current_x(*((*bnd)->current_edge), top_y);
+        }
+
+        ++bnd;
+    }
+
+    insert_horizontal_local_minima_into_ABL(top_y, minima_sorted, current_lm, active_bounds, rings,
+                                            scanbeam, cliptype, subject_fill_type, clip_fill_type);
+
+    process_horizontals(top_y, active_bounds, rings, scanbeam, cliptype, subject_fill_type,
+                        clip_fill_type);
+
+    // 4. Promote intermediate vertices
+
+    for (auto bnd = active_bounds.begin(); bnd != active_bounds.end(); ++bnd) {
+        if (is_intermediate(bnd, top_y)) {
+            if ((*bnd)->ring) {
+                add_point_to_ring(*(*bnd), (*bnd)->current_edge->top, rings);
+                insert_hot_pixels_in_path(*(*bnd), (*bnd)->current_edge->top, rings, false);
+            }
+            next_edge_in_bound(bnd, scanbeam);
+        }
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/quick_clip.hpp

@@ -0,0 +1,133 @@
+#pragma once
+
+#include <mapbox/geometry/box.hpp>
+#include <mapbox/geometry/multi_polygon.hpp>
+#include <mapbox/geometry/polygon.hpp>
+#include <mapbox/geometry/wagyu/wagyu.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+namespace quick_clip {
+
+template <typename T>
+mapbox::geometry::point<T> intersect(mapbox::geometry::point<T> a,
+                                     mapbox::geometry::point<T> b,
+                                     size_t edge,
+                                     mapbox::geometry::box<T> const& box) {
+    switch (edge) {
+    case 0:
+        return mapbox::geometry::point<T>(
+            static_cast<T>(a.x + static_cast<double>(b.x - a.x) * (box.min.y - a.y) / (b.y - a.y)),
+            box.min.y);
+
+    case 1:
+        return mapbox::geometry::point<T>(
+            box.max.x,
+            static_cast<T>(a.y + static_cast<double>(b.y - a.y) * (box.max.x - a.x) / (b.x - a.x)));
+
+    case 2:
+        return mapbox::geometry::point<T>(
+            static_cast<T>(a.x + static_cast<double>(b.x - a.x) * (box.max.y - a.y) / (b.y - a.y)),
+            box.max.y);
+
+    default: // case 3
+        return mapbox::geometry::point<T>(
+            box.min.x,
+            static_cast<T>(a.y + static_cast<double>(b.y - a.y) * (box.min.x - a.x) / (b.x - a.x)));
+    }
+}
+
+template <typename T>
+bool inside(mapbox::geometry::point<T> p, size_t edge, mapbox::geometry::box<T> const& b) {
+    switch (edge) {
+    case 0:
+        return p.y > b.min.y;
+
+    case 1:
+        return p.x < b.max.x;
+
+    case 2:
+        return p.y < b.max.y;
+
+    default: // case 3
+        return p.x > b.min.x;
+    }
+}
+
+template <typename T>
+mapbox::geometry::linear_ring<T> quick_lr_clip(mapbox::geometry::linear_ring<T> const& ring,
+                                      mapbox::geometry::box<T> const& b) {
+    mapbox::geometry::linear_ring<T> out = ring;
+
+    for (size_t edge = 0; edge < 4; edge++) {
+        if (out.size() > 0) {
+            mapbox::geometry::linear_ring<T> in = out;
+            mapbox::geometry::point<T> S = in[in.size() - 1];
+            out.resize(0);
+
+            for (size_t e = 0; e < in.size(); e++) {
+                mapbox::geometry::point<T> E = in[e];
+
+                if (inside(E, edge, b)) {
+                    if (!inside(S, edge, b)) {
+                        out.push_back(intersect(S, E, edge, b));
+                    }
+                    out.push_back(E);
+                } else if (inside(S, edge, b)) {
+                    out.push_back(intersect(S, E, edge, b));
+                }
+
+                S = E;
+            }
+        }
+    }
+
+    if (out.size() < 3) {
+        out.clear();
+        return out;
+    }
+    // Close the ring if the first/last point was outside
+    if (out[0] != out[out.size() - 1]) {
+        out.push_back(out[0]);
+    }
+    return out;
+}
+}
+
+template <typename T>
+mapbox::geometry::multi_polygon<T> clip(mapbox::geometry::polygon<T> const& poly,
+                                        mapbox::geometry::box<T> const& b,
+                                        fill_type subject_fill_type) {
+    mapbox::geometry::multi_polygon<T> result;
+    wagyu<T> clipper;
+    for (auto const& lr : poly) {
+        auto new_lr = quick_clip::quick_lr_clip(lr, b);
+        if (!new_lr.empty()) {
+            clipper.add_ring(new_lr, polygon_type_subject);
+        }
+    }
+    clipper.execute(clip_type_union, result, subject_fill_type, fill_type_even_odd);
+    return result;
+}
+
+template <typename T>
+mapbox::geometry::multi_polygon<T> clip(mapbox::geometry::multi_polygon<T> const& mp,
+                                        mapbox::geometry::box<T> const& b,
+                                        fill_type subject_fill_type) {
+    mapbox::geometry::multi_polygon<T> result;
+    wagyu<T> clipper;
+    for (auto const& poly : mp) {
+        for (auto const& lr : poly) {
+            auto new_lr = quick_clip::quick_lr_clip(lr, b);
+            if (!new_lr.empty()) {
+                clipper.add_ring(new_lr, polygon_type_subject);
+            }
+        }
+    }
+    clipper.execute(clip_type_union, result, subject_fill_type, fill_type_even_odd);
+    return result;
+}
+}
+}
+}

mapbox/geometry/wagyu/ring.hpp

@@ -0,0 +1,475 @@
+#pragma once
+
+#include <assert.h>
+#include <cmath>
+#include <deque>
+#include <list>
+#include <map>
+#include <mapbox/geometry/wagyu/point.hpp>
+#include <set>
+#include <sstream>
+#include <vector>
+
+#ifdef DEBUG
+#include <execinfo.h>
+#include <iostream>
+#include <sstream>
+#include <stdio.h>
+//
+// void* callstack[128];
+// int i, frames = backtrace(callstack, 128);
+// char** strs = backtrace_symbols(callstack, frames);
+// for (i = 0; i < frames; ++i) {
+//     printf("%s\n", strs[i]);
+// }
+// free(strs);
+#endif
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+// NOTE: ring and ring_ptr are forward declared in wagyu/point.hpp
+
+template <typename T>
+using ring_vector = std::vector<ring_ptr<T>>;
+
+template <typename T>
+using ring_list = std::list<ring_ptr<T>>;
+
+template <typename T>
+struct ring {
+    std::size_t ring_index; // To support unset 0 is undefined and indexes offset by 1
+    std::size_t size;
+    double area;
+    ring_ptr<T> parent;
+    ring_list<T> children;
+    point_ptr<T> points;
+    point_ptr<T> bottom_point;
+
+    ring(ring const&) = delete;
+    ring& operator=(ring const&) = delete;
+
+    ring()
+        : ring_index(0),
+          size(0),
+          area(std::numeric_limits<double>::quiet_NaN()),
+          parent(nullptr),
+          children(),
+          points(nullptr),
+          bottom_point(nullptr) {
+    }
+};
+
+template <typename T>
+using hot_pixel_vector = std::vector<mapbox::geometry::point<T>>;
+
+template <typename T>
+using hot_pixel_itr = typename hot_pixel_vector<T>::iterator;
+
+template <typename T>
+using hot_pixel_rev_itr = typename hot_pixel_vector<T>::reverse_iterator;
+
+template <typename T>
+struct ring_manager {
+
+    ring_list<T> children;
+    std::vector<point_ptr<T>> all_points;
+    hot_pixel_vector<T> hot_pixels;
+    hot_pixel_itr<T> current_hp_itr;
+    std::deque<point<T>> points;
+    std::deque<ring<T>> rings;
+    std::vector<point<T>> storage;
+    std::size_t index;
+
+    ring_manager(ring_manager const&) = delete;
+    ring_manager& operator=(ring_manager const&) = delete;
+
+    ring_manager()
+        : children(),
+          all_points(),
+          hot_pixels(),
+          current_hp_itr(hot_pixels.end()),
+          points(),
+          rings(),
+          storage(),
+          index(0) {
+    }
+};
+
+template <typename T>
+void preallocate_point_memory(ring_manager<T>& rings, std::size_t size) {
+    rings.storage.reserve(size);
+    rings.all_points.reserve(size);
+}
+
+template <typename T>
+ring_ptr<T> create_new_ring(ring_manager<T>& rings) {
+    rings.rings.emplace_back();
+    ring_ptr<T> result = &rings.rings.back();
+    result->ring_index = rings.index++;
+    return result;
+}
+
+template <typename T>
+point_ptr<T>
+create_new_point(ring_ptr<T> r, mapbox::geometry::point<T> const& pt, ring_manager<T>& rings) {
+    point_ptr<T> point;
+    if (rings.storage.size() < rings.storage.capacity()) {
+        rings.storage.emplace_back(r, pt);
+        point = &rings.storage.back();
+    } else {
+        rings.points.emplace_back(r, pt);
+        point = &rings.points.back();
+    }
+    rings.all_points.push_back(point);
+    return point;
+}
+
+template <typename T>
+point_ptr<T> create_new_point(ring_ptr<T> r,
+                              mapbox::geometry::point<T> const& pt,
+                              point_ptr<T> before_this_point,
+                              ring_manager<T>& rings) {
+    point_ptr<T> point;
+    if (rings.storage.size() < rings.storage.capacity()) {
+        rings.storage.emplace_back(r, pt, before_this_point);
+        point = &rings.storage.back();
+    } else {
+        rings.points.emplace_back(r, pt, before_this_point);
+        point = &rings.points.back();
+    }
+    rings.all_points.push_back(point);
+    return point;
+}
+
+template <typename T>
+void ring1_child_of_ring2(ring_ptr<T> ring1, ring_ptr<T> ring2, ring_manager<T>& manager) {
+    assert(ring1 != ring2);
+    if (ring1->parent == ring2) {
+        return;
+    }
+    if (ring1->parent == nullptr) {
+        manager.children.remove(ring1);
+    } else {
+        ring1->parent->children.remove(ring1);
+    }
+    if (ring2 == nullptr) {
+        ring1->parent = nullptr;
+        manager.children.push_back(ring1);
+    } else {
+        ring1->parent = ring2;
+        ring2->children.push_back(ring1);
+    }
+}
+
+template <typename T>
+void ring1_sibling_of_ring2(ring_ptr<T> ring1, ring_ptr<T> ring2, ring_manager<T>& manager) {
+    assert(ring1 != ring2);
+    if (ring1->parent == ring2->parent) {
+        return;
+    }
+    if (ring1->parent == nullptr) {
+        manager.children.remove(ring1);
+    } else {
+        ring1->parent->children.remove(ring1);
+    }
+    if (ring2->parent == nullptr) {
+        manager.children.push_back(ring1);
+    } else {
+        ring2->parent->children.push_back(ring1);
+    }
+    ring1->parent = ring2->parent;
+}
+
+template <typename T>
+void ring1_replaces_ring2(ring_ptr<T> ring1, ring_ptr<T> ring2, ring_manager<T>& manager) {
+    assert(ring1 != ring2);
+    if (ring2->parent == nullptr) {
+        manager.children.remove(ring2);
+    } else {
+        ring2->parent->children.remove(ring2);
+    }
+    for (auto& c : ring2->children) {
+        c->parent = ring1;
+    }
+    if (ring1 == nullptr) {
+        manager.children.splice(manager.children.end(), ring2->children);
+    } else {
+        ring1->children.splice(ring1->children.end(), ring2->children);
+    }
+    ring2->parent = nullptr;
+}
+
+template <typename T>
+void remove_ring(ring_ptr<T> r, ring_manager<T>& manager) {
+    if (r->parent == nullptr) {
+        manager.children.remove(r);
+        for (auto& c : r->children) {
+            c->parent = nullptr;
+        }
+        manager.children.splice(manager.children.end(), r->children);
+    } else {
+        r->parent->children.remove(r);
+        for (auto& c : r->children) {
+            c->parent = r->parent;
+        }
+        r->parent->children.splice(r->parent->children.end(), r->children);
+        r->parent = nullptr;
+    }
+}
+
+template <typename T>
+inline std::size_t ring_depth(ring_ptr<T> r) {
+    std::size_t depth = 0;
+    if (!r) {
+        return depth;
+    }
+    while (r->parent) {
+        depth++;
+        r = r->parent;
+    }
+    return depth;
+}
+
+template <typename T>
+inline bool ring_is_hole(ring_ptr<T> r) {
+    return ring_depth(r) & 1;
+}
+
+template <typename T>
+void set_next(const_point_ptr<T>& node, const const_point_ptr<T>& next_node) {
+    node->next = next_node;
+}
+
+template <typename T>
+point_ptr<T> get_next(const_point_ptr<T>& node) {
+    return node->next;
+}
+
+template <typename T>
+point_ptr<T> get_prev(const_point_ptr<T>& node) {
+    return node->prev;
+}
+
+template <typename T>
+void set_prev(const_point_ptr<T>& node, const const_point_ptr<T>& prev_node) {
+    node->prev = prev_node;
+}
+
+template <typename T>
+void init(const_point_ptr<T>& node) {
+    set_next(node, node);
+    set_prev(node, node);
+}
+
+template <typename T>
+std::size_t point_count(const const_point_ptr<T>& orig_node) {
+    std::size_t size = 0;
+    point_ptr<T> n = orig_node;
+    do {
+        n = get_next(n);
+        ++size;
+    } while (n != orig_node);
+    return size;
+}
+
+template <typename T>
+void link_before(point_ptr<T>& node, point_ptr<T>& new_node) {
+    point_ptr<T> prev_node = get_prev(node);
+    set_prev(new_node, prev_node);
+    set_next(new_node, node);
+    set_prev(node, new_node);
+    set_next(prev_node, new_node);
+}
+
+template <typename T>
+void link_after(point_ptr<T>& node, point_ptr<T>& new_node) {
+    point_ptr<T> next_node = get_next(node);
+    set_prev(new_node, node);
+    set_next(new_node, next_node);
+    set_next(node, new_node);
+    set_prev(next_node, new_node);
+}
+
+template <typename T>
+void transfer_point(point_ptr<T>& p, point_ptr<T>& b, point_ptr<T>& e) {
+    if (b != e) {
+        point_ptr<T> prev_p = get_prev(p);
+        point_ptr<T> prev_b = get_prev(b);
+        point_ptr<T> prev_e = get_prev(e);
+        set_next(prev_e, p);
+        set_prev(p, prev_e);
+        set_next(prev_b, e);
+        set_prev(e, prev_b);
+        set_next(prev_p, b);
+        set_prev(b, prev_p);
+    } else {
+        link_before(p, b);
+    }
+}
+
+template <typename T>
+void reverse_ring(point_ptr<T> pp) {
+    if (!pp) {
+        return;
+    }
+    point_ptr<T> pp1;
+    point_ptr<T> pp2;
+    pp1 = pp;
+    do {
+        pp2 = pp1->next;
+        pp1->next = pp1->prev;
+        pp1->prev = pp2;
+        pp1 = pp2;
+    } while (pp1 != pp);
+}
+
+template <typename T>
+double area_from_point(point_ptr<T> op, std::size_t& size) {
+    point_ptr<T> startOp = op;
+    size = 1;
+    double a = 0.0;
+    do {
+        ++size;
+        a += static_cast<double>(op->prev->x + op->x) * static_cast<double>(op->prev->y - op->y);
+        op = op->next;
+    } while (op != startOp);
+    return a * 0.5;
+}
+
+template <typename T>
+double area(ring_ptr<T> r) {
+    assert(r != nullptr);
+    if (std::isnan(r->area)) {
+        r->area = area_from_point(r->points, r->size);
+    }
+    return r->area;
+}
+
+#ifdef DEBUG
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const ring<T>& r) {
+    out << "  ring_index: " << r.ring_index << std::endl;
+    if (!r.parent) {
+        // out << "  parent_ring ptr: nullptr" << std::endl;
+        out << "  parent_index: -----" << std::endl;
+    } else {
+        // out << "  parent_ring ptr: " << r.parent << std::endl;
+        out << "  parent_ring idx: " << r.parent->ring_index << std::endl;
+    }
+    ring_ptr<T> n = const_cast<ring_ptr<T>>(&r);
+    if (ring_is_hole(n)) {
+        out << "  is_hole: true " << std::endl;
+    } else {
+        out << "  is_hole: false " << std::endl;
+    }
+    auto pt_itr = r.points;
+    if (pt_itr) {
+        out << "  area: " << r.area << std::endl;
+        out << "  points:" << std::endl;
+        out << "      [[[" << pt_itr->x << "," << pt_itr->y << "],";
+        pt_itr = pt_itr->next;
+        while (pt_itr != r.points) {
+            out << "[" << pt_itr->x << "," << pt_itr->y << "],";
+            pt_itr = pt_itr->next;
+        }
+        out << "[" << pt_itr->x << "," << pt_itr->y << "]]]" << std::endl;
+    } else {
+        out << "  area: NONE" << std::endl;
+        out << "  points: NONE" << std::endl;
+    }
+    return out;
+}
+
+template <typename T>
+std::string output_as_polygon(ring_ptr<T> r) {
+    std::ostringstream out;
+
+    auto pt_itr = r->points;
+    if (pt_itr) {
+        out << "[";
+        out << "[[" << pt_itr->x << "," << pt_itr->y << "],";
+        pt_itr = pt_itr->next;
+        while (pt_itr != r->points) {
+            out << "[" << pt_itr->x << "," << pt_itr->y << "],";
+            pt_itr = pt_itr->next;
+        }
+        out << "[" << pt_itr->x << "," << pt_itr->y << "]]";
+        for (auto const& c : r->children) {
+            pt_itr = c->points;
+            if (pt_itr) {
+                out << ",[[" << pt_itr->x << "," << pt_itr->y << "],";
+                pt_itr = pt_itr->next;
+                while (pt_itr != c->points) {
+                    out << "[" << pt_itr->x << "," << pt_itr->y << "],";
+                    pt_itr = pt_itr->next;
+                }
+                out << "[" << pt_itr->x << "," << pt_itr->y << "]]";
+            }
+        }
+        out << "]" << std::endl;
+    } else {
+        out << "[]" << std::endl;
+    }
+
+    return out.str();
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const ring_list<T>& rings) {
+    out << "START RING LIST" << std::endl;
+    for (auto& r : rings) {
+        out << " ring: " << r->ring_index << " - " << r << std::endl;
+        out << *r;
+    }
+    out << "END RING LIST" << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const ring_vector<T>& rings) {
+    out << "START RING VECTOR" << std::endl;
+    for (auto& r : rings) {
+        if (!r->points) {
+            continue;
+        }
+        out << " ring: " << r->ring_index << " - " << r << std::endl;
+        out << *r;
+    }
+    out << "END RING VECTOR" << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const std::deque<ring<T>>& rings) {
+    out << "START RING VECTOR" << std::endl;
+    for (auto& r : rings) {
+        if (!r.points) {
+            continue;
+        }
+        out << " ring: " << r.ring_index << std::endl;
+        out << r;
+    }
+    out << "END RING VECTOR" << std::endl;
+    return out;
+}
+
+template <class charT, class traits, typename T>
+inline std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& out,
+                                                     const hot_pixel_vector<T>& hp_vec) {
+    out << "Hot Pixels: " << std::endl;
+    for (auto& hp : hp_vec) {
+        out << hp << std::endl;
+    }
+    return out;
+}
+#endif
+}
+}
+}

mapbox/geometry/wagyu/ring_util.hpp

@@ -0,0 +1,906 @@
+#pragma once
+
+#ifdef DEBUG
+#include <iostream>
+// Example debug print for backtrace - only works on IOS
+#include <execinfo.h>
+#include <stdio.h>
+//
+// void* callstack[128];
+// int i, frames = backtrace(callstack, 128);
+// char** strs = backtrace_symbols(callstack, frames);
+// for (i = 0; i < frames; ++i) {
+//     printf("%s\n", strs[i]);
+// }
+// free(strs);
+#endif
+
+#include <queue>
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+void set_hole_state(active_bound_list_itr<T>& bnd,
+                    active_bound_list<T>& active_bounds,
+                    ring_manager<T>& rings) {
+    auto bnd2 = active_bound_list_rev_itr<T>(bnd);
+    bound_ptr<T> bndTmp = nullptr;
+    // Find first non line ring to the left of current bound.
+    while (bnd2 != active_bounds.rend()) {
+        if ((*bnd2)->ring && (*bnd2)->winding_delta != 0) {
+            if (!bndTmp) {
+                bndTmp = (*bnd2);
+            } else if (bndTmp->ring == (*bnd2)->ring) {
+                bndTmp = nullptr;
+            }
+        }
+        ++bnd2;
+    }
+    if (!bndTmp) {
+        (*bnd)->ring->parent = nullptr;
+        rings.children.push_back((*bnd)->ring);
+    } else {
+        (*bnd)->ring->parent = bndTmp->ring;
+        bndTmp->ring->children.push_back((*bnd)->ring);
+    }
+}
+
+template <typename T>
+void set_hole_state(active_bound_list_rev_itr<T>& bnd,
+                    active_bound_list<T>& active_bounds,
+                    ring_manager<T>& rings) {
+    auto bnd2 = std::next(bnd);
+    bound_ptr<T> bndTmp = nullptr;
+    // Find first non line ring to the left of current bound.
+    while (bnd2 != active_bounds.rend()) {
+        if ((*bnd2)->ring && (*bnd2)->winding_delta != 0) {
+            if (!bndTmp) {
+                bndTmp = (*bnd2);
+            } else if (bndTmp->ring == (*bnd2)->ring) {
+                bndTmp = nullptr;
+            }
+        }
+        ++bnd2;
+    }
+
+    if (!bndTmp) {
+        (*bnd)->ring->parent = nullptr;
+        rings.children.push_back((*bnd)->ring);
+    } else {
+        (*bnd)->ring->parent = bndTmp->ring;
+        bndTmp->ring->children.push_back((*bnd)->ring);
+    }
+}
+
+template <typename T>
+void update_current_hp_itr(T scanline_y, ring_manager<T>& rings) {
+    while (rings.current_hp_itr->y > scanline_y) {
+        ++rings.current_hp_itr;
+    }
+}
+
+template <typename T>
+struct hot_pixel_sorter {
+    inline bool operator()(mapbox::geometry::point<T> const& pt1,
+                           mapbox::geometry::point<T> const& pt2) {
+        if (pt1.y == pt2.y) {
+            return pt1.x < pt2.x;
+        } else {
+            return pt1.y > pt2.y;
+        }
+    }
+};
+
+// Due to the nature of floating point calculations
+// and the high likely hood of values around X.5, we
+// need to fudge what is X.5 some for our rounding.
+const double rounding_offset = 1e-12;
+const double rounding_offset_y = 5e-13;
+
+template <typename T>
+T round_towards_min(double val) {
+    // 0.5 rounds to 0
+    // 0.0 rounds to 0
+    // -0.5 rounds to -1
+    return static_cast<T>(std::ceil(val - 0.5 + rounding_offset));
+}
+
+template <typename T>
+T round_towards_max(double val) {
+    // 0.5 rounds to 1
+    // 0.0 rounds to 0
+    // -0.5 rounds to 0
+    return static_cast<T>(std::floor(val + 0.5 + rounding_offset));
+}
+
+template <typename T>
+inline T get_edge_min_x(edge<T> const& edge, const T current_y) {
+    if (is_horizontal(edge)) {
+        if (edge.bot.x < edge.top.x) {
+            return edge.bot.x;
+        } else {
+            return edge.top.x;
+        }
+    } else if (edge.dx > 0.0) {
+        if (current_y == edge.top.y) {
+            return edge.top.x;
+        } else {
+            double lower_range_y = static_cast<double>(current_y - edge.bot.y) - 0.5;
+            double return_val = static_cast<double>(edge.bot.x) + edge.dx * lower_range_y;
+            T value = round_towards_min<T>(return_val);
+            return value;
+        }
+    } else {
+        if (current_y == edge.bot.y) {
+            return edge.bot.x;
+        } else {
+            double return_val =
+                static_cast<double>(edge.bot.x) +
+                edge.dx * (static_cast<double>(current_y - edge.bot.y) + 0.5 - rounding_offset_y);
+            T value = round_towards_min<T>(return_val);
+            return value;
+        }
+    }
+}
+
+template <typename T>
+inline T get_edge_max_x(edge<T> const& edge, const T current_y) {
+    if (is_horizontal(edge)) {
+        if (edge.bot.x > edge.top.x) {
+            return edge.bot.x;
+        } else {
+            return edge.top.x;
+        }
+    } else if (edge.dx < 0.0) {
+        if (current_y == edge.top.y) {
+            return edge.top.x;
+        } else {
+            double lower_range_y = static_cast<double>(current_y - edge.bot.y) - 0.5;
+            double return_val = static_cast<double>(edge.bot.x) + edge.dx * lower_range_y;
+            T value = round_towards_max<T>(return_val);
+            return value;
+        }
+    } else {
+        if (current_y == edge.bot.y) {
+            return edge.bot.x;
+        } else {
+            double return_val =
+                static_cast<double>(edge.bot.x) +
+                edge.dx * (static_cast<double>(current_y - edge.bot.y) + 0.5 - rounding_offset_y);
+            T value = round_towards_max<T>(return_val);
+            return value;
+        }
+    }
+}
+
+template <typename T>
+void hot_pixel_set_left_to_right(T y,
+                                 T start_x,
+                                 T end_x,
+                                 bound<T>& bnd,
+                                 ring_manager<T>& rings,
+                                 hot_pixel_itr<T>& itr,
+                                 hot_pixel_itr<T>& end,
+                                 bool add_end_point) {
+    T x_min = get_edge_min_x(*(bnd.current_edge), y);
+    x_min = std::max(x_min, start_x);
+    T x_max = get_edge_max_x(*(bnd.current_edge), y);
+    x_max = std::min(x_max, end_x);
+    for (; itr != end; ++itr) {
+        if (itr->x < x_min) {
+            continue;
+        }
+        if (itr->x > x_max) {
+            break;
+        }
+        if (!add_end_point && itr->x == end_x) {
+            continue;
+        }
+        point_ptr<T> op = bnd.ring->points;
+        bool to_front = (bnd.side == edge_left);
+        if (to_front && (*itr == *op)) {
+            continue;
+        } else if (!to_front && (*itr == *op->prev)) {
+            continue;
+        }
+        point_ptr<T> new_point = create_new_point(bnd.ring, *itr, op, rings);
+        if (to_front) {
+            bnd.ring->points = new_point;
+        }
+    }
+}
+
+template <typename T>
+void hot_pixel_set_right_to_left(T y,
+                                 T start_x,
+                                 T end_x,
+                                 bound<T>& bnd,
+                                 ring_manager<T>& rings,
+                                 hot_pixel_rev_itr<T>& itr,
+                                 hot_pixel_rev_itr<T>& end,
+                                 bool add_end_point) {
+    T x_min = get_edge_min_x(*(bnd.current_edge), y);
+    x_min = std::max(x_min, end_x);
+    T x_max = get_edge_max_x(*(bnd.current_edge), y);
+    x_max = std::min(x_max, start_x);
+    for (; itr != end; ++itr) {
+        if (itr->x > x_max) {
+            continue;
+        }
+        if (itr->x < x_min) {
+            break;
+        }
+        if (!add_end_point && itr->x == end_x) {
+            continue;
+        }
+        point_ptr<T> op = bnd.ring->points;
+        bool to_front = (bnd.side == edge_left);
+        if (to_front && (*itr == *op)) {
+            continue;
+        } else if (!to_front && (*itr == *op->prev)) {
+            continue;
+        }
+        point_ptr<T> new_point = create_new_point(bnd.ring, *itr, op, rings);
+        if (to_front) {
+            bnd.ring->points = new_point;
+        }
+    }
+}
+
+template <typename T>
+void sort_hot_pixels(ring_manager<T>& rings) {
+    std::sort(rings.hot_pixels.begin(), rings.hot_pixels.end(), hot_pixel_sorter<T>());
+    auto last = std::unique(rings.hot_pixels.begin(), rings.hot_pixels.end());
+    rings.hot_pixels.erase(last, rings.hot_pixels.end());
+}
+
+template <typename T>
+void insert_hot_pixels_in_path(bound<T>& bnd,
+                               mapbox::geometry::point<T> const& end_pt,
+                               ring_manager<T>& rings,
+                               bool add_end_point) {
+    if (end_pt == bnd.last_point) {
+        return;
+    }
+
+    T start_y = bnd.last_point.y;
+    T start_x = bnd.last_point.x;
+    T end_y = end_pt.y;
+    T end_x = end_pt.x;
+
+    auto itr = rings.current_hp_itr;
+    while (itr->y <= start_y && itr != rings.hot_pixels.begin()) {
+        --itr;
+    }
+    if (start_x > end_x) {
+        for (; itr != rings.hot_pixels.end();) {
+            if (itr->y > start_y) {
+                ++itr;
+                continue;
+            }
+            if (itr->y < end_y) {
+                break;
+            }
+            T y = itr->y;
+            auto last_itr = hot_pixel_rev_itr<T>(itr);
+            while (itr != rings.hot_pixels.end() && itr->y == y) {
+                ++itr;
+            }
+            auto first_itr = hot_pixel_rev_itr<T>(itr);
+            bool add_end_point_itr = (y != end_pt.y || add_end_point);
+            hot_pixel_set_right_to_left(y, start_x, end_x, bnd, rings, first_itr, last_itr,
+                                        add_end_point_itr);
+        }
+    } else {
+        for (; itr != rings.hot_pixels.end();) {
+            if (itr->y > start_y) {
+                ++itr;
+                continue;
+            }
+            if (itr->y < end_y) {
+                break;
+            }
+            T y = itr->y;
+            auto first_itr = itr;
+            while (itr != rings.hot_pixels.end() && itr->y == y) {
+                ++itr;
+            }
+            auto last_itr = itr;
+            bool add_end_point_itr = (y != end_pt.y || add_end_point);
+            hot_pixel_set_left_to_right(y, start_x, end_x, bnd, rings, first_itr, last_itr,
+                                        add_end_point_itr);
+        }
+    }
+    bnd.last_point = end_pt;
+}
+
+template <typename T>
+void add_to_hot_pixels(mapbox::geometry::point<T> const& pt, ring_manager<T>& rings) {
+    rings.hot_pixels.push_back(pt);
+}
+
+template <typename T>
+void add_first_point(active_bound_list_itr<T>& bnd,
+                     active_bound_list<T>& active_bounds,
+                     mapbox::geometry::point<T> const& pt,
+                     ring_manager<T>& rings) {
+
+    ring_ptr<T> r = create_new_ring(rings);
+    (*bnd)->ring = r;
+    r->points = create_new_point(r, pt, rings);
+    set_hole_state(bnd, active_bounds, rings);
+    (*bnd)->last_point = pt;
+}
+
+template <typename T>
+void add_first_point(active_bound_list_rev_itr<T>& bnd,
+                     active_bound_list<T>& active_bounds,
+                     mapbox::geometry::point<T> const& pt,
+                     ring_manager<T>& rings) {
+    ring_ptr<T> r = create_new_ring(rings);
+    // no ring currently set!
+    (*bnd)->ring = r;
+    r->points = create_new_point(r, pt, rings);
+    set_hole_state(bnd, active_bounds, rings);
+    (*bnd)->last_point = pt;
+}
+
+template <typename T>
+void add_point_to_ring(bound<T>& bnd,
+                       mapbox::geometry::point<T> const& pt,
+                       ring_manager<T>& rings) {
+    assert(bnd.ring);
+    // Handle hot pixels
+    insert_hot_pixels_in_path(bnd, pt, rings, false);
+
+    // bnd.ring->points is the 'Left-most' point & bnd.ring->points->prev is the
+    // 'Right-most'
+    point_ptr<T> op = bnd.ring->points;
+    bool to_front = (bnd.side == edge_left);
+    if (to_front && (pt == *op)) {
+        return;
+    } else if (!to_front && (pt == *op->prev)) {
+        return;
+    }
+    point_ptr<T> new_point = create_new_point(bnd.ring, pt, bnd.ring->points, rings);
+    if (to_front) {
+        bnd.ring->points = new_point;
+    }
+}
+
+template <typename T>
+void add_point(active_bound_list_itr<T>& bnd,
+               active_bound_list<T>& active_bounds,
+               mapbox::geometry::point<T> const& pt,
+               ring_manager<T>& rings) {
+    if (!(*bnd)->ring) {
+        add_first_point(bnd, active_bounds, pt, rings);
+    } else {
+        add_point_to_ring(*(*bnd), pt, rings);
+    }
+}
+
+template <typename T>
+void add_point(active_bound_list_rev_itr<T>& bnd,
+               active_bound_list<T>& active_bounds,
+               mapbox::geometry::point<T> const& pt,
+               ring_manager<T>& rings) {
+    if (!(*bnd)->ring) {
+        add_first_point(bnd, active_bounds, pt, rings);
+    } else {
+        add_point_to_ring(*(*bnd), pt, rings);
+    }
+}
+
+template <typename T>
+void add_local_minimum_point(active_bound_list_itr<T> b1,
+                             active_bound_list_itr<T> b2,
+                             active_bound_list<T>& active_bounds,
+                             mapbox::geometry::point<T> const& pt,
+                             ring_manager<T>& rings) {
+    active_bound_list_itr<T> b;
+    active_bound_list_rev_itr<T> prev_bound;
+    active_bound_list_rev_itr<T> prev_b1(b1);
+    active_bound_list_rev_itr<T> prev_b2(b2);
+    if (is_horizontal(*((*b2)->current_edge)) ||
+        ((*b1)->current_edge->dx > (*b2)->current_edge->dx)) {
+        add_point(b1, active_bounds, pt, rings);
+        (*b2)->last_point = pt;
+        (*b2)->ring = (*b1)->ring;
+        (*b1)->side = edge_left;
+        (*b2)->side = edge_right;
+        b = b1;
+        if (prev_b1 != active_bounds.rend() && std::prev(b) == b2) {
+            prev_bound = prev_b2;
+        } else {
+            prev_bound = prev_b1;
+        }
+    } else {
+        add_point(b2, active_bounds, pt, rings);
+        (*b1)->last_point = pt;
+        (*b1)->ring = (*b2)->ring;
+        (*b1)->side = edge_right;
+        (*b2)->side = edge_left;
+        b = b2;
+        if (prev_b2 != active_bounds.rend() && std::prev(b) == b1) {
+            prev_bound = prev_b1;
+        } else {
+            prev_bound = prev_b2;
+        }
+    }
+}
+
+template <typename T>
+inline double get_dx(point<T> const& pt1, point<T> const& pt2) {
+    if (pt1.y == pt2.y) {
+        return std::numeric_limits<double>::infinity();
+    } else {
+        return static_cast<double>(pt2.x - pt2.x) / static_cast<double>(pt2.y - pt1.y);
+    }
+}
+
+template <typename T>
+bool first_is_bottom_point(const_point_ptr<T> btmPt1, const_point_ptr<T> btmPt2) {
+    point_ptr<T> p = btmPt1->prev;
+    while ((*p == *btmPt1) && (p != btmPt1)) {
+        p = p->prev;
+    }
+    double dx1p = std::fabs(get_dx(*btmPt1, *p));
+
+    p = btmPt1->next;
+    while ((*p == *btmPt1) && (p != btmPt1)) {
+        p = p->next;
+    }
+    double dx1n = std::fabs(get_dx(*btmPt1, *p));
+
+    p = btmPt2->prev;
+    while ((*p == *btmPt2) && (p != btmPt2)) {
+        p = p->prev;
+    }
+    double dx2p = std::fabs(get_dx(*btmPt2, *p));
+
+    p = btmPt2->next;
+    while ((*p == *btmPt2) && (p != btmPt2)) {
+        p = p->next;
+    }
+    double dx2n = std::fabs(get_dx(*btmPt2, *p));
+
+    if (values_are_equal(std::max(dx1p, dx1n), std::max(dx2p, dx2n)) &&
+        values_are_equal(std::min(dx1p, dx1n), std::min(dx2p, dx2n))) {
+        std::size_t s = 0;
+        return area_from_point(btmPt1, s) > 0.0; // if otherwise identical use orientation
+    } else {
+        return (greater_than_or_equal(dx1p, dx2p) && greater_than_or_equal(dx1p, dx2n)) ||
+               (greater_than_or_equal(dx1n, dx2p) && greater_than_or_equal(dx1n, dx2n));
+    }
+}
+
+template <typename T>
+point_ptr<T> get_bottom_point(point_ptr<T> pp) {
+    point_ptr<T> dups = nullptr;
+    point_ptr<T> p = pp->next;
+    while (p != pp) {
+        if (p->y > pp->y) {
+            pp = p;
+            dups = nullptr;
+        } else if (p->y == pp->y && p->x <= pp->x) {
+            if (p->x < pp->x) {
+                dups = nullptr;
+                pp = p;
+            } else {
+                if (p->next != pp && p->prev != pp) {
+                    dups = p;
+                }
+            }
+        }
+        p = p->next;
+    }
+    if (dups) {
+        // there appears to be at least 2 vertices at bottom_point so ...
+        while (dups != p) {
+            if (!first_is_bottom_point(p, dups)) {
+                pp = dups;
+            }
+            dups = dups->next;
+            while (*dups != *pp) {
+                dups = dups->next;
+            }
+        }
+    }
+    return pp;
+}
+
+template <typename T>
+ring_ptr<T> get_lower_most_ring(ring_ptr<T> outRec1, ring_ptr<T> outRec2) {
+    // work out which polygon fragment has the correct hole state ...
+    if (!outRec1->bottom_point) {
+        outRec1->bottom_point = get_bottom_point(outRec1->points);
+    }
+    if (!outRec2->bottom_point) {
+        outRec2->bottom_point = get_bottom_point(outRec2->points);
+    }
+    point_ptr<T> OutPt1 = outRec1->bottom_point;
+    point_ptr<T> OutPt2 = outRec2->bottom_point;
+    if (OutPt1->y > OutPt2->y) {
+        return outRec1;
+    } else if (OutPt1->y < OutPt2->y) {
+        return outRec2;
+    } else if (OutPt1->x < OutPt2->x) {
+        return outRec1;
+    } else if (OutPt1->x > OutPt2->x) {
+        return outRec2;
+    } else if (OutPt1->next == OutPt1) {
+        return outRec2;
+    } else if (OutPt2->next == OutPt2) {
+        return outRec1;
+    } else if (first_is_bottom_point(OutPt1, OutPt2)) {
+        return outRec1;
+    } else {
+        return outRec2;
+    }
+}
+
+template <typename T>
+bool ring1_child_below_ring2(ring_ptr<T> ring1, ring_ptr<T> ring2) {
+    do {
+        ring1 = ring1->parent;
+        if (ring1 == ring2) {
+            return true;
+        }
+    } while (ring1);
+    return false;
+}
+
+template <typename T>
+void update_points_ring(ring_ptr<T> ring) {
+    point_ptr<T> op = ring->points;
+    do {
+        op->ring = ring;
+        op = op->prev;
+    } while (op != ring->points);
+}
+
+template <typename T>
+void append_ring(active_bound_list_itr<T>& b1,
+                 active_bound_list_itr<T>& b2,
+                 active_bound_list<T>& active_bounds,
+                 ring_manager<T>& manager) {
+    // get the start and ends of both output polygons ...
+    ring_ptr<T> outRec1 = (*b1)->ring;
+    ring_ptr<T> outRec2 = (*b2)->ring;
+
+    ring_ptr<T> keep_ring;
+    bound_ptr<T> keep_bound;
+    ring_ptr<T> remove_ring;
+    bound_ptr<T> remove_bound;
+    if (ring1_child_below_ring2(outRec1, outRec2)) {
+        keep_ring = outRec2;
+        keep_bound = *b2;
+        remove_ring = outRec1;
+        remove_bound = *b1;
+    } else if (ring1_child_below_ring2(outRec2, outRec1)) {
+        keep_ring = outRec1;
+        keep_bound = *b1;
+        remove_ring = outRec2;
+        remove_bound = *b2;
+    } else if (outRec1 == get_lower_most_ring(outRec1, outRec2)) {
+        keep_ring = outRec1;
+        keep_bound = *b1;
+        remove_ring = outRec2;
+        remove_bound = *b2;
+    } else {
+        keep_ring = outRec2;
+        keep_bound = *b2;
+        remove_ring = outRec1;
+        remove_bound = *b1;
+    }
+
+    // get the start and ends of both output polygons and
+    // join b2 poly onto b1 poly and delete pointers to b2 ...
+
+    point_ptr<T> p1_lft = keep_ring->points;
+    point_ptr<T> p1_rt = p1_lft->prev;
+    point_ptr<T> p2_lft = remove_ring->points;
+    point_ptr<T> p2_rt = p2_lft->prev;
+
+    // join b2 poly onto b1 poly and delete pointers to b2 ...
+    if (keep_bound->side == edge_left) {
+        if (remove_bound->side == edge_left) {
+            // z y x a b c
+            reverse_ring(p2_lft);
+            p2_lft->next = p1_lft;
+            p1_lft->prev = p2_lft;
+            p1_rt->next = p2_rt;
+            p2_rt->prev = p1_rt;
+            keep_ring->points = p2_rt;
+        } else {
+            // x y z a b c
+            p2_rt->next = p1_lft;
+            p1_lft->prev = p2_rt;
+            p2_lft->prev = p1_rt;
+            p1_rt->next = p2_lft;
+            keep_ring->points = p2_lft;
+        }
+    } else {
+        if (remove_bound->side == edge_right) {
+            // a b c z y x
+            reverse_ring(p2_lft);
+            p1_rt->next = p2_rt;
+            p2_rt->prev = p1_rt;
+            p2_lft->next = p1_lft;
+            p1_lft->prev = p2_lft;
+        } else {
+            // a b c x y z
+            p1_rt->next = p2_lft;
+            p2_lft->prev = p1_rt;
+            p1_lft->prev = p2_rt;
+            p2_rt->next = p1_lft;
+        }
+    }
+
+    keep_ring->bottom_point = nullptr;
+    bool keep_is_hole = ring_is_hole(keep_ring);
+    bool remove_is_hole = ring_is_hole(remove_ring);
+
+    remove_ring->points = nullptr;
+    remove_ring->bottom_point = nullptr;
+    if (keep_is_hole != remove_is_hole) {
+        ring1_replaces_ring2(keep_ring->parent, remove_ring, manager);
+    } else {
+        ring1_replaces_ring2(keep_ring, remove_ring, manager);
+    }
+
+    update_points_ring(keep_ring);
+
+    // nb: safe because we only get here via AddLocalMaxPoly
+    keep_bound->ring = nullptr;
+    remove_bound->ring = nullptr;
+
+    for (auto& b : active_bounds) {
+        if (b->ring == remove_ring) {
+            b->ring = keep_ring;
+            b->side = keep_bound->side;
+            break; // Not sure why there is a break here but was transfered logic from angus
+        }
+    }
+}
+
+template <typename T>
+void add_local_maximum_point(active_bound_list_itr<T>& b1,
+                             active_bound_list_itr<T>& b2,
+                             mapbox::geometry::point<T> const& pt,
+                             ring_manager<T>& rings,
+                             active_bound_list<T>& active_bounds) {
+    insert_hot_pixels_in_path(*(*b2), pt, rings, false);
+    add_point(b1, active_bounds, pt, rings);
+    if ((*b1)->ring == (*b2)->ring) {
+        (*b1)->ring = nullptr;
+        (*b2)->ring = nullptr;
+        // I am not certain that order is important here?
+    } else if ((*b1)->ring->ring_index < (*b2)->ring->ring_index) {
+        append_ring(b1, b2, active_bounds, rings);
+    } else {
+        append_ring(b2, b1, active_bounds, rings);
+    }
+}
+
+enum point_in_polygon_result : std::int8_t {
+    point_on_polygon = -1,
+    point_inside_polygon = 0,
+    point_outside_polygon = 1
+};
+
+template <typename T>
+point_in_polygon_result point_in_polygon(point<T> const& pt, point_ptr<T> op) {
+    // returns 0 if false, +1 if true, -1 if pt ON polygon boundary
+    point_in_polygon_result result = point_outside_polygon;
+    point_ptr<T> startOp = op;
+    do {
+        if (op->next->y == pt.y) {
+            if ((op->next->x == pt.x) ||
+                (op->y == pt.y && ((op->next->x > pt.x) == (op->x < pt.x)))) {
+                return point_on_polygon;
+            }
+        }
+        if ((op->y < pt.y) != (op->next->y < pt.y)) {
+            if (op->x >= pt.x) {
+                if (op->next->x > pt.x) {
+                    // Switch between point outside polygon and point inside
+                    // polygon
+                    if (result == point_outside_polygon) {
+                        result = point_inside_polygon;
+                    } else {
+                        result = point_outside_polygon;
+                    }
+                } else {
+                    double d =
+                        static_cast<double>(op->x - pt.x) *
+                            static_cast<double>(op->next->y - pt.y) -
+                        static_cast<double>(op->next->x - pt.x) * static_cast<double>(op->y - pt.y);
+                    if (value_is_zero(d)) {
+                        return point_on_polygon;
+                    }
+                    if ((d > 0) == (op->next->y > op->y)) {
+                        // Switch between point outside polygon and point inside
+                        // polygon
+                        if (result == point_outside_polygon) {
+                            result = point_inside_polygon;
+                        } else {
+                            result = point_outside_polygon;
+                        }
+                    }
+                }
+            } else {
+                if (op->next->x > pt.x) {
+                    double d =
+                        static_cast<double>(op->x - pt.x) *
+                            static_cast<double>(op->next->y - pt.y) -
+                        static_cast<double>(op->next->x - pt.x) * static_cast<double>(op->y - pt.y);
+                    if (value_is_zero(d)) {
+                        return point_on_polygon;
+                    }
+                    if ((d > 0) == (op->next->y > op->y)) {
+                        // Switch between point outside polygon and point inside
+                        // polygon
+                        if (result == point_outside_polygon) {
+                            result = point_inside_polygon;
+                        } else {
+                            result = point_outside_polygon;
+                        }
+                    }
+                }
+            }
+        }
+        op = op->next;
+    } while (startOp != op);
+    return result;
+}
+
+template <typename T>
+point_in_polygon_result point_in_polygon(mapbox::geometry::point<double> const& pt,
+                                         point_ptr<T> op) {
+    // returns 0 if false, +1 if true, -1 if pt ON polygon boundary
+    point_in_polygon_result result = point_outside_polygon;
+    point_ptr<T> startOp = op;
+    do {
+        double op_x = static_cast<double>(op->x);
+        double op_y = static_cast<double>(op->y);
+        double op_next_x = static_cast<double>(op->next->x);
+        double op_next_y = static_cast<double>(op->next->y);
+        if (values_are_equal(op_next_y, pt.y)) {
+            if (values_are_equal(op_next_x, pt.x) ||
+                (values_are_equal(op_y, pt.y) && ((op_next_x > pt.x) == (op_x < pt.x)))) {
+                return point_on_polygon;
+            }
+        }
+        if ((op_y < pt.y) != (op_next_y < pt.y)) {
+            if (greater_than_or_equal(op_x, pt.x)) {
+                if (op_next_x > pt.x) {
+                    // Switch between point outside polygon and point inside
+                    // polygon
+                    if (result == point_outside_polygon) {
+                        result = point_inside_polygon;
+                    } else {
+                        result = point_outside_polygon;
+                    }
+                } else {
+                    double d =
+                        (op_x - pt.x) * (op_next_y - pt.y) - (op_next_x - pt.x) * (op_y - pt.y);
+                    if (value_is_zero(d)) {
+                        return point_on_polygon;
+                    }
+                    if ((d > 0.0) == (op_next_y > op->y)) {
+                        // Switch between point outside polygon and point inside
+                        // polygon
+                        if (result == point_outside_polygon) {
+                            result = point_inside_polygon;
+                        } else {
+                            result = point_outside_polygon;
+                        }
+                    }
+                }
+            } else {
+                if (op_next_x > pt.x) {
+                    double d =
+                        (op_x - pt.x) * (op_next_y - pt.y) - (op_next_x - pt.x) * (op_y - pt.y);
+                    if (value_is_zero(d)) {
+                        return point_on_polygon;
+                    }
+                    if ((d > 0.0) == (op_next_y > op->y)) {
+                        // Switch between point outside polygon and point inside
+                        // polygon
+                        if (result == point_outside_polygon) {
+                            result = point_inside_polygon;
+                        } else {
+                            result = point_outside_polygon;
+                        }
+                    }
+                }
+            }
+        }
+        op = op->next;
+    } while (startOp != op);
+    return result;
+}
+
+template <typename T>
+point_in_polygon_result inside_or_outside_special(point_ptr<T> first_pt, point_ptr<T> other_poly) {
+
+    if (value_is_zero(area(first_pt->ring))) {
+        return point_inside_polygon;
+    }
+    if (value_is_zero(area(other_poly->ring))) {
+        return point_outside_polygon;
+    }
+    point_ptr<T> pt = first_pt;
+    do {
+        if (*pt == *(pt->prev) || *pt == *(pt->next) || *(pt->next) == *(pt->prev) ||
+            slopes_equal(*(pt->prev), *pt, *(pt->next))) {
+            pt = pt->next;
+            continue;
+        }
+        double dx = ((pt->prev->x - pt->x) / 3.0) + ((pt->next->x - pt->x) / 3.0);
+        double dy = ((pt->prev->y - pt->y) / 3.0) + ((pt->next->y - pt->y) / 3.0);
+        mapbox::geometry::point<double> offset_pt(pt->x + dx, pt->y + dy);
+        point_in_polygon_result res = point_in_polygon(offset_pt, pt);
+        if (res != point_inside_polygon) {
+            offset_pt.x = pt->x - dx;
+            offset_pt.y = pt->y - dy;
+            res = point_in_polygon(offset_pt, pt);
+            if (res != point_inside_polygon) {
+                pt = pt->next;
+                continue;
+            }
+        }
+        res = point_in_polygon(offset_pt, other_poly);
+        if (res == point_on_polygon) {
+            pt = pt->next;
+            continue;
+        }
+        return res;
+    } while (pt != first_pt);
+    return point_inside_polygon;
+}
+
+template <typename T>
+bool poly2_contains_poly1(ring_ptr<T> ring1, ring_ptr<T> ring2) {
+    point_ptr<T> outpt1 = ring1->points->next;
+    point_ptr<T> outpt2 = ring2->points->next;
+    point_ptr<T> op = outpt1;
+    do {
+        // nb: PointInPolygon returns 0 if false, +1 if true, -1 if pt on polygon
+        point_in_polygon_result res = point_in_polygon(*op, outpt2);
+        if (res != point_on_polygon) {
+            return res == point_inside_polygon;
+        }
+        op = op->next;
+    } while (op != outpt1);
+    point_in_polygon_result res = inside_or_outside_special(outpt1, outpt2);
+    return res == point_inside_polygon;
+}
+
+template <typename T>
+void dispose_out_points(point_ptr<T>& pp) {
+    if (pp == nullptr) {
+        return;
+    }
+    pp->prev->next = nullptr;
+    while (pp) {
+        point_ptr<T> tmpPp = pp;
+        pp = pp->next;
+        tmpPp->next = tmpPp;
+        tmpPp->prev = tmpPp;
+        tmpPp->ring = nullptr;
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/scanbeam.hpp

@@ -0,0 +1,37 @@
+#pragma once
+
+#include <queue>
+
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+using scanbeam_list = std::priority_queue<T>;
+
+template <typename T>
+bool pop_from_scanbeam(T& Y, scanbeam_list<T>& scanbeam) {
+    if (scanbeam.empty()) {
+        return false;
+    }
+    Y = scanbeam.top();
+    scanbeam.pop();
+    while (!scanbeam.empty() && Y == scanbeam.top()) {
+        scanbeam.pop();
+    } // Pop duplicates.
+    return true;
+}
+
+template <typename T>
+void setup_scanbeam(local_minimum_list<T>& minima_list, scanbeam_list<T>& scanbeam) {
+
+    for (auto lm = minima_list.begin(); lm != minima_list.end(); ++lm) {
+        scanbeam.push(lm->y);
+    }
+}
+}
+}
+}

mapbox/geometry/wagyu/snap_rounding.hpp

@@ -0,0 +1,172 @@
+#pragma once
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+#include <mapbox/geometry/wagyu/bound.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/edge.hpp>
+#include <mapbox/geometry/wagyu/intersect.hpp>
+#include <mapbox/geometry/wagyu/intersect_util.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/ring_util.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+void process_hot_pixel_intersections(T top_y,
+                                     active_bound_list<T>& active_bounds,
+                                     ring_manager<T>& rings) {
+    if (active_bounds.empty()) {
+        return;
+    }
+
+    update_current_x(active_bounds, top_y);
+    // bubblesort ...
+    bool isModified;
+    do {
+        isModified = false;
+        auto bnd = active_bounds.begin();
+        auto bnd_next = std::next(bnd);
+        while (bnd_next != active_bounds.end()) {
+            if ((*bnd)->current_x > (*bnd_next)->current_x &&
+                !slopes_equal(*(*bnd)->current_edge, *(*bnd_next)->current_edge)) {
+                mapbox::geometry::point<double> pt;
+                if (!get_edge_intersection<T, double>(*((*bnd)->current_edge),
+                                                      *((*bnd_next)->current_edge), pt)) {
+                    // LCOV_EXCL_START
+                    throw std::runtime_error("Edges do not intersect!");
+                    // LCOV_EXCL_END
+                }
+                add_to_hot_pixels(round_point<T>(pt), rings);
+                swap_positions_in_ABL(bnd, bnd_next, active_bounds);
+                bnd_next = std::next(bnd);
+                isModified = true;
+            } else {
+                bnd = bnd_next;
+                ++bnd_next;
+            }
+        }
+    } while (isModified);
+}
+
+template <typename T>
+void process_hot_pixel_edges_at_top_of_scanbeam(T top_y,
+                                                scanbeam_list<T>& scanbeam,
+                                                active_bound_list<T>& active_bounds,
+                                                ring_manager<T>& rings) {
+    for (auto bnd = active_bounds.begin(); bnd != active_bounds.end();) {
+        auto bnd_2 = std::next(bnd);
+        while ((*bnd)->current_edge != (*bnd)->edges.end() &&
+               (*bnd)->current_edge->top.y == top_y) {
+            add_to_hot_pixels((*bnd)->current_edge->top, rings);
+            if (current_edge_is_horizontal<T>(bnd)) {
+                (*bnd)->current_x = static_cast<double>((*bnd)->current_edge->top.x);
+                if ((*bnd)->current_edge->bot.x < (*bnd)->current_edge->top.x) {
+                    // left to right
+                    auto bnd_next = std::next(bnd);
+                    while (bnd_next != active_bounds.end() &&
+                           (*bnd_next)->current_x < (*bnd)->current_x) {
+                        if (std::llround((*bnd_next)->current_edge->top.y) != top_y &&
+                            std::llround((*bnd_next)->current_edge->bot.y) != top_y) {
+                            mapbox::geometry::point<T> pt(std::llround((*bnd_next)->current_x),
+                                                          top_y);
+                            add_to_hot_pixels(pt, rings);
+                        }
+                        swap_positions_in_ABL(bnd, bnd_next, active_bounds);
+                        bnd_next = std::next(bnd);
+                    }
+                } else {
+                    // right to left
+                    if (bnd != active_bounds.begin()) {
+                        auto bnd_prev = std::prev(bnd);
+                        while (bnd != active_bounds.begin() &&
+                               (*bnd_prev)->current_x > (*bnd)->current_x) {
+                            if (std::llround((*bnd_prev)->current_edge->top.y) != top_y &&
+                                std::llround((*bnd_prev)->current_edge->bot.y) != top_y) {
+                                mapbox::geometry::point<T> pt(std::llround((*bnd_prev)->current_x),
+                                                              top_y);
+                                add_to_hot_pixels(pt, rings);
+                            }
+                            swap_positions_in_ABL(bnd, bnd_prev, active_bounds);
+                            bnd_prev = std::prev(bnd);
+                        }
+                    }
+                }
+            }
+            next_edge_in_bound(bnd, scanbeam);
+        }
+        if ((*bnd)->current_edge == (*bnd)->edges.end()) {
+            active_bounds.erase(bnd);
+        }
+        bnd = bnd_2;
+    }
+}
+
+template <typename T>
+void insert_local_minima_into_ABL_hot_pixel(T top_y,
+                                            local_minimum_ptr_list<T>& minima_sorted,
+                                            local_minimum_ptr_list_itr<T>& lm,
+                                            active_bound_list<T>& active_bounds,
+                                            ring_manager<T>& rings,
+                                            scanbeam_list<T>& scanbeam) {
+    while (lm != minima_sorted.end() && (*lm)->y == top_y) {
+        add_to_hot_pixels((*lm)->left_bound.edges.front().bot, rings);
+        auto& left_bound = (*lm)->left_bound;
+        left_bound.current_edge = left_bound.edges.begin();
+        left_bound.current_x = static_cast<double>(left_bound.current_edge->bot.x);
+        auto lb_abl_itr = insert_bound_into_ABL(left_bound, active_bounds);
+        if (!current_edge_is_horizontal<T>(lb_abl_itr)) {
+            scanbeam.push((*lb_abl_itr)->current_edge->top.y);
+        }
+        auto& right_bound = (*lm)->right_bound;
+        right_bound.current_edge = right_bound.edges.begin();
+        right_bound.current_x = static_cast<double>(right_bound.current_edge->bot.x);
+        auto rb_abl_itr = insert_bound_into_ABL(right_bound, lb_abl_itr, active_bounds);
+        if (!current_edge_is_horizontal<T>(rb_abl_itr)) {
+            scanbeam.push((*rb_abl_itr)->current_edge->top.y);
+        }
+        ++lm;
+    }
+}
+
+template <typename T>
+void build_hot_pixels(local_minimum_list<T>& minima_list, ring_manager<T>& rings) {
+    active_bound_list<T> active_bounds;
+    scanbeam_list<T> scanbeam;
+    T scanline_y = std::numeric_limits<T>::max();
+
+    local_minimum_ptr_list<T> minima_sorted;
+    minima_sorted.reserve(minima_list.size());
+    for (auto& lm : minima_list) {
+        minima_sorted.push_back(&lm);
+    }
+    std::stable_sort(minima_sorted.begin(), minima_sorted.end(), local_minimum_sorter<T>());
+    local_minimum_ptr_list_itr<T> current_lm = minima_sorted.begin();
+
+    setup_scanbeam(minima_list, scanbeam);
+
+    // Estimate size for reserving hot pixels
+    std::size_t reserve = 0;
+    for (auto& lm : minima_list) {
+        reserve += lm.left_bound.edges.size() + 2;
+        reserve += lm.right_bound.edges.size() + 2;
+    }
+    rings.hot_pixels.reserve(reserve);
+
+    while (pop_from_scanbeam(scanline_y, scanbeam) || current_lm != minima_sorted.end()) {
+
+        process_hot_pixel_intersections(scanline_y, active_bounds, rings);
+
+        insert_local_minima_into_ABL_hot_pixel(scanline_y, minima_sorted, current_lm, active_bounds,
+                                               rings, scanbeam);
+
+        process_hot_pixel_edges_at_top_of_scanbeam(scanline_y, scanbeam, active_bounds, rings);
+    }
+    preallocate_point_memory(rings, rings.hot_pixels.size());
+    sort_hot_pixels(rings);
+}
+}
+}
+}

mapbox/geometry/wagyu/util.hpp

@@ -0,0 +1,79 @@
+#pragma once
+
+#include <cmath>
+
+#include <mapbox/geometry/point.hpp>
+#include <mapbox/geometry/polygon.hpp>
+#include <mapbox/geometry/wagyu/point.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+double area(mapbox::geometry::linear_ring<T> const& poly) {
+    std::size_t size = poly.size();
+    if (size < 3) {
+        return 0.0;
+    }
+
+    double a = 0.0;
+    auto itr = poly.begin();
+    auto itr_prev = poly.end();
+    --itr_prev;
+    a += static_cast<double>(itr_prev->x + itr->x) * static_cast<double>(itr_prev->y - itr->y);
+    ++itr;
+    itr_prev = poly.begin();
+    for (; itr != poly.end(); ++itr, ++itr_prev) {
+        a += static_cast<double>(itr_prev->x + itr->x) * static_cast<double>(itr_prev->y - itr->y);
+    }
+    return -a * 0.5;
+}
+
+inline bool value_is_zero(double val) {
+    return std::fabs(val) < std::numeric_limits<double>::epsilon();
+}
+
+inline bool values_are_equal(double x, double y) {
+    return value_is_zero(x - y);
+}
+
+inline bool values_near_equal(double x, double y) {
+    return std::fabs(x - y) < (5.0 * std::numeric_limits<double>::epsilon());
+}
+
+inline bool greater_than_or_equal(double x, double y) {
+    return x > y || values_are_equal(x, y);
+}
+
+template <typename T>
+bool slopes_equal(mapbox::geometry::point<T> const& pt1,
+                  mapbox::geometry::point<T> const& pt2,
+                  mapbox::geometry::point<T> const& pt3) {
+    return (pt1.y - pt2.y) * (pt2.x - pt3.x) == (pt1.x - pt2.x) * (pt2.y - pt3.y);
+}
+
+template <typename T>
+bool slopes_equal(mapbox::geometry::wagyu::point<T> const& pt1,
+                  mapbox::geometry::wagyu::point<T> const& pt2,
+                  mapbox::geometry::point<T> const& pt3) {
+    return (pt1.y - pt2.y) * (pt2.x - pt3.x) == (pt1.x - pt2.x) * (pt2.y - pt3.y);
+}
+
+template <typename T>
+bool slopes_equal(mapbox::geometry::wagyu::point<T> const& pt1,
+                  mapbox::geometry::wagyu::point<T> const& pt2,
+                  mapbox::geometry::wagyu::point<T> const& pt3) {
+    return (pt1.y - pt2.y) * (pt2.x - pt3.x) == (pt1.x - pt2.x) * (pt2.y - pt3.y);
+}
+
+template <typename T>
+bool slopes_equal(mapbox::geometry::point<T> const& pt1,
+                  mapbox::geometry::point<T> const& pt2,
+                  mapbox::geometry::point<T> const& pt3,
+                  mapbox::geometry::point<T> const& pt4) {
+    return (pt1.y - pt2.y) * (pt3.x - pt4.x) == (pt1.x - pt2.x) * (pt3.y - pt4.y);
+}
+}
+}
+}

mapbox/geometry/wagyu/vatti.hpp

@@ -0,0 +1,74 @@
+#pragma once
+
+#include <algorithm>
+#include <set>
+
+#include <mapbox/geometry/wagyu/active_bound_list.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/intersect_util.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/local_minimum_util.hpp>
+#include <mapbox/geometry/wagyu/process_horizontal.hpp>
+#include <mapbox/geometry/wagyu/process_maxima.hpp>
+#include <mapbox/geometry/wagyu/ring.hpp>
+#include <mapbox/geometry/wagyu/ring_util.hpp>
+#include <mapbox/geometry/wagyu/util.hpp>
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+bool execute_vatti(local_minimum_list<T>& minima_list,
+                   ring_manager<T>& rings,
+                   clip_type cliptype,
+                   fill_type subject_fill_type,
+                   fill_type clip_fill_type) {
+
+    if (minima_list.empty()) {
+        return false;
+    }
+
+    active_bound_list<T> active_bounds;
+    scanbeam_list<T> scanbeam;
+    T scanline_y = std::numeric_limits<T>::max();
+
+    local_minimum_ptr_list<T> minima_sorted;
+    minima_sorted.reserve(minima_list.size());
+    for (auto& lm : minima_list) {
+        minima_sorted.push_back(&lm);
+    }
+    std::stable_sort(minima_sorted.begin(), minima_sorted.end(), local_minimum_sorter<T>());
+    local_minimum_ptr_list_itr<T> current_lm = minima_sorted.begin();
+    // std::clog << output_all_edges(minima_sorted) << std::endl;
+
+    setup_scanbeam(minima_list, scanbeam);
+    rings.current_hp_itr = rings.hot_pixels.begin();
+
+    while (pop_from_scanbeam(scanline_y, scanbeam) || current_lm != minima_sorted.end()) {
+
+        process_intersections(scanline_y, active_bounds, cliptype, subject_fill_type,
+                              clip_fill_type, rings);
+
+        update_current_hp_itr(scanline_y, rings);
+
+        // First we process bounds that has already been added to the active bound list --
+        // if the active bound list is empty local minima that are at this scanline_y and
+        // have a horizontal edge at the local minima will be processed
+        process_edges_at_top_of_scanbeam(scanline_y, active_bounds, scanbeam, minima_sorted,
+                                         current_lm, rings, cliptype, subject_fill_type,
+                                         clip_fill_type);
+
+        // Next we will add local minima bounds to the active bounds list that are on the local
+        // minima queue at
+        // this current scanline_y
+        insert_local_minima_into_ABL(scanline_y, minima_sorted, current_lm, active_bounds, rings,
+                                     scanbeam, cliptype, subject_fill_type, clip_fill_type);
+    }
+    // std::clog << rings.rings << std::endl;
+    // std::clog << output_as_polygon(rings.all_rings[0]);
+    return true;
+}
+}
+}
+}

mapbox/geometry/wagyu/wagyu.hpp

@@ -0,0 +1,137 @@
+#pragma once
+
+#include <list>
+
+#include <mapbox/geometry/box.hpp>
+#include <mapbox/geometry/line_string.hpp>
+#include <mapbox/geometry/multi_polygon.hpp>
+#include <mapbox/geometry/polygon.hpp>
+
+#include <mapbox/geometry/wagyu/build_local_minima_list.hpp>
+#include <mapbox/geometry/wagyu/build_result.hpp>
+#include <mapbox/geometry/wagyu/config.hpp>
+#include <mapbox/geometry/wagyu/local_minimum.hpp>
+#include <mapbox/geometry/wagyu/snap_rounding.hpp>
+#include <mapbox/geometry/wagyu/topology_correction.hpp>
+#include <mapbox/geometry/wagyu/vatti.hpp>
+
+#define WAGYU_MAJOR_VERSION 0
+#define WAGYU_MINOR_VERSION 3
+#define WAGYU_PATCH_VERSION 0
+
+#define WAGYU_VERSION (WAGYU_MAJOR_VERSION * 100000) + (WAGYU_MINOR_VERSION * 100) + (WAGYU_PATCH_VERSION)
+
+namespace mapbox {
+namespace geometry {
+namespace wagyu {
+
+template <typename T>
+class wagyu {
+private:
+    using value_type = T;
+
+    local_minimum_list<value_type> minima_list;
+    bool reverse_output;
+
+    wagyu(wagyu const&) = delete;
+    wagyu& operator=(wagyu const&) = delete;
+
+public:
+    wagyu() : minima_list(), reverse_output(false) {
+    }
+
+    ~wagyu() {
+        clear();
+    }
+
+    bool add_ring(mapbox::geometry::linear_ring<value_type> const& pg,
+                  polygon_type p_type = polygon_type_subject) {
+        return add_linear_ring(pg, minima_list, p_type);
+    }
+
+    bool add_polygon(mapbox::geometry::polygon<value_type> const& ppg,
+                     polygon_type p_type = polygon_type_subject) {
+        bool result = false;
+        for (auto const& r : ppg) {
+            if (add_ring(r, p_type)) {
+                result = true;
+            }
+        }
+        return result;
+    }
+
+    void reverse_rings(bool value) {
+        reverse_output = value;
+    }
+
+    void clear() {
+        minima_list.clear();
+    }
+
+    mapbox::geometry::box<value_type> get_bounds() {
+        mapbox::geometry::point<value_type> min = { 0, 0 };
+        mapbox::geometry::point<value_type> max = { 0, 0 };
+        if (minima_list.empty()) {
+            return mapbox::geometry::box<value_type>(min, max);
+        }
+        bool first_set = false;
+        for (auto const& lm : minima_list) {
+            if (!lm.left_bound.edges.empty()) {
+                if (!first_set) {
+                    min = lm.left_bound.edges.front().top;
+                    max = lm.left_bound.edges.back().bot;
+                    first_set = true;
+                } else {
+                    min.y = std::min(min.y, lm.left_bound.edges.front().top.y);
+                    max.y = std::max(max.y, lm.left_bound.edges.back().bot.y);
+                    max.x = std::max(max.x, lm.left_bound.edges.back().top.x);
+                    min.x = std::min(min.x, lm.left_bound.edges.back().top.x);
+                }
+                for (auto const& e : lm.left_bound.edges) {
+                    max.x = std::max(max.x, e.bot.x);
+                    min.x = std::min(min.x, e.bot.x);
+                }
+            }
+            if (!lm.right_bound.edges.empty()) {
+                if (!first_set) {
+                    min = lm.right_bound.edges.front().top;
+                    max = lm.right_bound.edges.back().bot;
+                    first_set = true;
+                } else {
+                    min.y = std::min(min.y, lm.right_bound.edges.front().top.y);
+                    max.y = std::max(max.y, lm.right_bound.edges.back().bot.y);
+                    max.x = std::max(max.x, lm.right_bound.edges.back().top.x);
+                    min.x = std::min(min.x, lm.right_bound.edges.back().top.x);
+                }
+                for (auto const& e : lm.right_bound.edges) {
+                    max.x = std::max(max.x, e.bot.x);
+                    min.x = std::min(min.x, e.bot.x);
+                }
+            }
+        }
+        return mapbox::geometry::box<value_type>(min, max);
+    }
+
+    bool execute(clip_type cliptype,
+                 mapbox::geometry::multi_polygon<value_type>& solution,
+                 fill_type subject_fill_type,
+                 fill_type clip_fill_type) {
+
+        ring_manager<T> rings;
+
+        build_hot_pixels(minima_list, rings);
+
+        if (!execute_vatti(minima_list, rings, cliptype, subject_fill_type, clip_fill_type)) {
+            return false;
+        }
+
+        do_simple_polygons(rings);
+
+        build_result(solution, rings, reverse_output);
+
+        return true;
+    }
+};
+}
+}
+}

mapbox/optional.hpp

@@ -0,0 +1,74 @@
+#ifndef MAPBOX_UTIL_OPTIONAL_HPP
+#define MAPBOX_UTIL_OPTIONAL_HPP
+
+#pragma message("This implementation of optional is deprecated. See https://github.com/mapbox/variant/issues/64.")
+
+#include <type_traits>
+#include <utility>
+
+#include <mapbox/variant.hpp>
+
+namespace mapbox {
+namespace util {
+
+template <typename T>
+class optional
+{
+    static_assert(!std::is_reference<T>::value, "optional doesn't support references");
+
+    struct none_type
+    {
+    };
+
+    variant<none_type, T> variant_;
+
+public:
+    optional() = default;
+
+    optional(optional const& rhs)
+    {
+        if (this != &rhs)
+        { // protect against invalid self-assignment
+            variant_ = rhs.variant_;
+        }
+    }
+
+    optional(T const& v) { variant_ = v; }
+
+    explicit operator bool() const noexcept { return variant_.template is<T>(); }
+
+    T const& get() const { return variant_.template get<T>(); }
+    T& get() { return variant_.template get<T>(); }
+
+    T const& operator*() const { return this->get(); }
+    T operator*() { return this->get(); }
+
+    optional& operator=(T const& v)
+    {
+        variant_ = v;
+        return *this;
+    }
+
+    optional& operator=(optional const& rhs)
+    {
+        if (this != &rhs)
+        {
+            variant_ = rhs.variant_;
+        }
+        return *this;
+    }
+
+    template <typename... Args>
+    void emplace(Args&&... args)
+    {
+        variant_ = T{std::forward<Args>(args)...};
+    }
+
+    void reset() { variant_ = none_type{}; }
+
+}; // class optional
+
+} // namespace util
+} // namespace mapbox
+
+#endif // MAPBOX_UTIL_OPTIONAL_HPP

mapbox/recursive_wrapper.hpp

@@ -0,0 +1,122 @@
+#ifndef MAPBOX_UTIL_RECURSIVE_WRAPPER_HPP
+#define MAPBOX_UTIL_RECURSIVE_WRAPPER_HPP
+
+// Based on variant/recursive_wrapper.hpp from boost.
+//
+// Original license:
+//
+// Copyright (c) 2002-2003
+// Eric Friedman, Itay Maman
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+#include <cassert>
+#include <utility>
+
+namespace mapbox {
+namespace util {
+
+template <typename T>
+class recursive_wrapper
+{
+
+    T* p_;
+
+    void assign(T const& rhs)
+    {
+        this->get() = rhs;
+    }
+
+public:
+    using type = T;
+
+    /**
+     * Default constructor default initializes the internally stored value.
+     * For POD types this means nothing is done and the storage is
+     * uninitialized.
+     *
+     * @throws std::bad_alloc if there is insufficient memory for an object
+     *         of type T.
+     * @throws any exception thrown by the default constructur of T.
+     */
+    recursive_wrapper()
+        : p_(new T){}
+
+    ~recursive_wrapper() noexcept { delete p_; }
+
+    recursive_wrapper(recursive_wrapper const& operand)
+        : p_(new T(operand.get())) {}
+
+    recursive_wrapper(T const& operand)
+        : p_(new T(operand)) {}
+
+    recursive_wrapper(recursive_wrapper&& operand)
+        : p_(new T(std::move(operand.get()))) {}
+
+    recursive_wrapper(T&& operand)
+        : p_(new T(std::move(operand))) {}
+
+    inline recursive_wrapper& operator=(recursive_wrapper const& rhs)
+    {
+        assign(rhs.get());
+        return *this;
+    }
+
+    inline recursive_wrapper& operator=(T const& rhs)
+    {
+        assign(rhs);
+        return *this;
+    }
+
+    inline void swap(recursive_wrapper& operand) noexcept
+    {
+        T* temp = operand.p_;
+        operand.p_ = p_;
+        p_ = temp;
+    }
+
+    recursive_wrapper& operator=(recursive_wrapper&& rhs) noexcept
+    {
+        swap(rhs);
+        return *this;
+    }
+
+    recursive_wrapper& operator=(T&& rhs)
+    {
+        get() = std::move(rhs);
+        return *this;
+    }
+
+    T& get()
+    {
+        assert(p_);
+        return *get_pointer();
+    }
+
+    T const& get() const
+    {
+        assert(p_);
+        return *get_pointer();
+    }
+
+    T* get_pointer() { return p_; }
+
+    const T* get_pointer() const { return p_; }
+
+    operator T const&() const { return this->get(); }
+
+    operator T&() { return this->get(); }
+
+}; // class recursive_wrapper
+
+template <typename T>
+inline void swap(recursive_wrapper<T>& lhs, recursive_wrapper<T>& rhs) noexcept
+{
+    lhs.swap(rhs);
+}
+} // namespace util
+} // namespace mapbox
+
+#endif // MAPBOX_UTIL_RECURSIVE_WRAPPER_HPP

mapbox/variant_io.hpp

@@ -0,0 +1,45 @@
+#ifndef MAPBOX_UTIL_VARIANT_IO_HPP
+#define MAPBOX_UTIL_VARIANT_IO_HPP
+
+#include <iosfwd>
+
+#include <mapbox/variant.hpp>
+
+namespace mapbox {
+namespace util {
+
+namespace detail {
+// operator<< helper
+template <typename Out>
+class printer
+{
+public:
+    explicit printer(Out& out)
+        : out_(out) {}
+    printer& operator=(printer const&) = delete;
+
+    // visitor
+    template <typename T>
+    void operator()(T const& operand) const
+    {
+        out_ << operand;
+    }
+
+private:
+    Out& out_;
+};
+}
+
+// operator<<
+template <typename CharT, typename Traits, typename... Types>
+VARIANT_INLINE std::basic_ostream<CharT, Traits>&
+operator<<(std::basic_ostream<CharT, Traits>& out, variant<Types...> const& rhs)
+{
+    detail::printer<std::basic_ostream<CharT, Traits>> visitor(out);
+    apply_visitor(visitor, rhs);
+    return out;
+}
+} // namespace util
+} // namespace mapbox
+
+#endif // MAPBOX_UTIL_VARIANT_IO_HPP

mapbox/variant_visitor.hpp

@@ -0,0 +1,38 @@
+#ifndef MAPBOX_UTIL_VARIANT_VISITOR_HPP
+#define MAPBOX_UTIL_VARIANT_VISITOR_HPP
+
+namespace mapbox {
+namespace util {
+
+template <typename... Fns>
+struct visitor;
+
+template <typename Fn>
+struct visitor<Fn> : Fn
+{
+    using type = Fn;
+    using Fn::operator();
+
+    visitor(Fn fn) : Fn(fn) {}
+};
+
+template <typename Fn, typename... Fns>
+struct visitor<Fn, Fns...> : Fn, visitor<Fns...>
+{
+    using type = visitor;
+    using Fn::operator();
+    using visitor<Fns...>::operator();
+
+    visitor(Fn fn, Fns... fns) : Fn(fn), visitor<Fns...>(fns...) {}
+};
+
+template <typename... Fns>
+visitor<Fns...> make_visitor(Fns... fns)
+{
+    return visitor<Fns...>(fns...);
+}
+
+} // namespace util
+} // namespace mapbox
+
+#endif // MAPBOX_UTIL_VARIANT_VISITOR_HPP

mbtiles.c

@@ -1,238 +0,0 @@
-// for vasprintf() on Linux
-#define _GNU_SOURCE
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sqlite3.h>
-#include "pool.h"
-#include "tile.h"
-
-sqlite3 *mbtiles_open(char *dbname, char **argv) {
-	sqlite3 *outdb;
-
-	if (sqlite3_open(dbname, &outdb) != SQLITE_OK) {
-		fprintf(stderr, "%s: %s: %s\n", argv[0], dbname, sqlite3_errmsg(outdb));
-		exit(EXIT_FAILURE);
-	}
-
-	char *err = NULL;
-	if (sqlite3_exec(outdb, "PRAGMA synchronous=0", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: async: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "PRAGMA locking_mode=EXCLUSIVE", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: async: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "PRAGMA journal_mode=DELETE", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: async: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "CREATE TABLE metadata (name text, value text);", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: create metadata table: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "CREATE TABLE tiles (zoom_level integer, tile_column integer, tile_row integer, tile_data blob);", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: create tiles table: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "create unique index name on metadata (name);", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: index metadata: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_exec(outdb, "create unique index tile_index on tiles (zoom_level, tile_column, tile_row);", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: index tiles: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-
-	return outdb;
-}
-
-void mbtiles_write_tile(sqlite3 *outdb, int z, int tx, int ty, const char *data, int size) {
-	sqlite3_stmt *stmt;
-	const char *query = "insert into tiles (zoom_level, tile_column, tile_row, tile_data) values (?, ?, ?, ?)";
-	if (sqlite3_prepare_v2(outdb, query, -1, &stmt, NULL) != SQLITE_OK) {
-		fprintf(stderr, "sqlite3 insert prep failed\n");
-		exit(EXIT_FAILURE);
-	}
-
-	sqlite3_bind_int(stmt, 1, z);
-	sqlite3_bind_int(stmt, 2, tx);
-	sqlite3_bind_int(stmt, 3, (1 << z) - 1 - ty);
-	sqlite3_bind_blob(stmt, 4, data, size, NULL);
-
-	if (sqlite3_step(stmt) != SQLITE_DONE) {
-		fprintf(stderr, "sqlite3 insert failed: %s\n", sqlite3_errmsg(outdb));
-	}
-	if (sqlite3_finalize(stmt) != SQLITE_OK) {
-		fprintf(stderr, "sqlite3 finalize failed: %s\n", sqlite3_errmsg(outdb));
-	}
-}
-
-static void quote(char **buf, const char *s) {
-	char tmp[strlen(s) * 8 + 1];
-	char *out = tmp;
-
-	for (; *s != '\0'; s++) {
-		unsigned char ch = (unsigned char) *s;
-
-		if (ch == '\\' || ch == '\"') {
-			*out++ = '\\';
-			*out++ = ch;
-		} else if (ch < ' ') {
-			sprintf(out, "\\u%04x", ch);
-			out = out + strlen(out);
-		} else {
-			*out++ = ch;
-		}
-	}
-
-	*out = '\0';
-	*buf = realloc(*buf, strlen(*buf) + strlen(tmp) + 1);
-	if (*buf == NULL) {
-		perror("realloc");
-		exit(EXIT_FAILURE);
-	}
-	strcat(*buf, tmp);
-}
-
-static void aprintf(char **buf, const char *format, ...) {
-	va_list ap;
-	char *tmp;
-
-	va_start(ap, format);
-	if (vasprintf(&tmp, format, ap) < 0) {
-		fprintf(stderr, "memory allocation failure\n");
-		exit(EXIT_FAILURE);
-	}
-	va_end(ap);
-
-	*buf = realloc(*buf, strlen(*buf) + strlen(tmp) + 1);
-	strcat(*buf, tmp);
-	free(tmp);
-}
-
-void mbtiles_write_metadata(sqlite3 *outdb, const char *fname, char **layername, int minzoom, int maxzoom, double minlat, double minlon, double maxlat, double maxlon, double midlat, double midlon, struct pool **file_keys, int nlayers) {
-	char *sql, *err;
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('name', %Q);", fname);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set name in metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('description', %Q);", fname);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set description in metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('version', %d);", 1);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('minzoom', %d);", minzoom);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('maxzoom', %d);", maxzoom);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('center', '%f,%f,%d');", midlon, midlat, maxzoom);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('bounds', '%f,%f,%f,%f');", minlon, minlat, maxlon, maxlat);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('type', %Q);", "overlay");
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('format', %Q);", "pbf");
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-
-	char *buf = strdup("{");
-	aprintf(&buf, "\"vector_layers\": [ ");
-
-	int i;
-	for (i = 0; i < nlayers; i++) {
-		if (i != 0) {
-			aprintf(&buf, ", ");
-		}
-
-		aprintf(&buf, "{ \"id\": \"");
-		quote(&buf, layername[i]);
-		aprintf(&buf, "\", \"description\": \"\", \"minzoom\": %d, \"maxzoom\": %d, \"fields\": {", minzoom, maxzoom);
-
-		struct pool_val *pv;
-		for (pv = file_keys[i]->head; pv != NULL; pv = pv->next) {
-			aprintf(&buf, "\"");
-			quote(&buf, pv->s);
-
-			if (pv->type == VT_NUMBER) {
-				aprintf(&buf, "\": \"Number\"");
-			} else if (pv->type == VT_BOOLEAN) {
-				aprintf(&buf, "\": \"Boolean\"");
-			} else {
-				aprintf(&buf, "\": \"String\"");
-			}
-
-			if (pv->next != NULL) {
-				aprintf(&buf, ", ");
-			}
-		}
-
-		aprintf(&buf, "} }");
-	}
-
-	aprintf(&buf, " ] }");
-
-	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('json', %Q);", buf);
-	if (sqlite3_exec(outdb, sql, NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "set metadata: %s\n", err);
-		exit(EXIT_FAILURE);
-	}
-	sqlite3_free(sql);
-	free(buf);
-}
-
-void mbtiles_close(sqlite3 *outdb, char **argv) {
-	char *err;
-
-	if (sqlite3_exec(outdb, "ANALYZE;", NULL, NULL, &err) != SQLITE_OK) {
-		fprintf(stderr, "%s: ANALYZE failed: %s\n", argv[0], err);
-		exit(EXIT_FAILURE);
-	}
-	if (sqlite3_close(outdb) != SQLITE_OK) {
-		fprintf(stderr, "%s: could not close database: %s\n", argv[0], sqlite3_errmsg(outdb));
-		exit(EXIT_FAILURE);
-	}
-}

mbtiles.cpp

@@ -0,0 +1,661 @@
+// for vasprintf() on Linux
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sqlite3.h>
+#include <vector>
+#include <string>
+#include <set>
+#include <map>
+#include "mvt.hpp"
+#include "mbtiles.hpp"
+#include "text.hpp"
+#include "milo/dtoa_milo.h"
+
+sqlite3 *mbtiles_open(char *dbname, char **argv, int forcetable) {
+	sqlite3 *outdb;
+
+	if (sqlite3_open(dbname, &outdb) != SQLITE_OK) {
+		fprintf(stderr, "%s: %s: %s\n", argv[0], dbname, sqlite3_errmsg(outdb));
+		exit(EXIT_FAILURE);
+	}
+
+	char *err = NULL;
+	if (sqlite3_exec(outdb, "PRAGMA synchronous=0", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: async: %s\n", argv[0], err);
+		exit(EXIT_FAILURE);
+	}
+	if (sqlite3_exec(outdb, "PRAGMA locking_mode=EXCLUSIVE", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: async: %s\n", argv[0], err);
+		exit(EXIT_FAILURE);
+	}
+	if (sqlite3_exec(outdb, "PRAGMA journal_mode=DELETE", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: async: %s\n", argv[0], err);
+		exit(EXIT_FAILURE);
+	}
+	if (sqlite3_exec(outdb, "CREATE TABLE metadata (name text, value text);", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: create metadata table: %s\n", argv[0], err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	if (sqlite3_exec(outdb, "CREATE TABLE tiles (zoom_level integer, tile_column integer, tile_row integer, tile_data blob);", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: create tiles table: %s\n", argv[0], err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	if (sqlite3_exec(outdb, "create unique index name on metadata (name);", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: index metadata: %s\n", argv[0], err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	if (sqlite3_exec(outdb, "create unique index tile_index on tiles (zoom_level, tile_column, tile_row);", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: index tiles: %s\n", argv[0], err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	return outdb;
+}
+
+void mbtiles_write_tile(sqlite3 *outdb, int z, int tx, int ty, const char *data, int size) {
+	sqlite3_stmt *stmt;
+	const char *query = "insert into tiles (zoom_level, tile_column, tile_row, tile_data) values (?, ?, ?, ?)";
+	if (sqlite3_prepare_v2(outdb, query, -1, &stmt, NULL) != SQLITE_OK) {
+		fprintf(stderr, "sqlite3 insert prep failed\n");
+		exit(EXIT_FAILURE);
+	}
+
+	sqlite3_bind_int(stmt, 1, z);
+	sqlite3_bind_int(stmt, 2, tx);
+	sqlite3_bind_int(stmt, 3, (1 << z) - 1 - ty);
+	sqlite3_bind_blob(stmt, 4, data, size, NULL);
+
+	if (sqlite3_step(stmt) != SQLITE_DONE) {
+		fprintf(stderr, "sqlite3 insert failed: %s\n", sqlite3_errmsg(outdb));
+	}
+	if (sqlite3_finalize(stmt) != SQLITE_OK) {
+		fprintf(stderr, "sqlite3 finalize failed: %s\n", sqlite3_errmsg(outdb));
+	}
+}
+
+static void quote(std::string &buf, std::string const &s) {
+	for (size_t i = 0; i < s.size(); i++) {
+		unsigned char ch = s[i];
+
+		if (ch == '\\' || ch == '\"') {
+			buf.push_back('\\');
+			buf.push_back(ch);
+		} else if (ch < ' ') {
+			char tmp[7];
+			sprintf(tmp, "\\u%04x", ch);
+			buf.append(std::string(tmp));
+		} else {
+			buf.push_back(ch);
+		}
+	}
+}
+
+void aprintf(std::string *buf, const char *format, ...) {
+	va_list ap;
+	char *tmp;
+
+	va_start(ap, format);
+	if (vasprintf(&tmp, format, ap) < 0) {
+		fprintf(stderr, "memory allocation failure\n");
+		exit(EXIT_FAILURE);
+	}
+	va_end(ap);
+
+	buf->append(tmp, strlen(tmp));
+	free(tmp);
+}
+
+bool type_and_string::operator<(const type_and_string &o) const {
+	if (string < o.string) {
+		return true;
+	}
+	if (string == o.string && type < o.type) {
+		return true;
+	}
+	return false;
+}
+
+bool type_and_string::operator!=(const type_and_string &o) const {
+	if (type != o.type) {
+		return true;
+	}
+	if (string != o.string) {
+		return true;
+	}
+	return false;
+}
+
+std::string tilestats(std::map<std::string, layermap_entry> const &layermap1, size_t elements) {
+	// Consolidate layers/attributes whose names are truncated
+	std::vector<std::map<std::string, layermap_entry>> lmv;
+	lmv.push_back(layermap1);
+	std::map<std::string, layermap_entry> layermap = merge_layermaps(lmv, true);
+
+	std::string out = "{\n";
+
+	out.append("\t\"layerCount\": ");
+	out.append(std::to_string(layermap.size()));
+	out.append(",\n");
+
+	out.append("\t\"layers\": [\n");
+
+	bool first = true;
+	for (auto layer : layermap) {
+		if (!first) {
+			out.append(",\n");
+		}
+		first = false;
+
+		out.append("\t\t{\n");
+
+		out.append("\t\t\t\"layer\": \"");
+		quote(out, layer.first.c_str());
+		out.append("\",\n");
+
+		out.append("\t\t\t\"count\": ");
+		out.append(std::to_string(layer.second.points + layer.second.lines + layer.second.polygons));
+		out.append(",\n");
+
+		std::string geomtype = "Polygon";
+		if (layer.second.points >= layer.second.lines && layer.second.points >= layer.second.polygons) {
+			geomtype = "Point";
+		} else if (layer.second.lines >= layer.second.polygons && layer.second.lines >= layer.second.points) {
+			geomtype = "LineString";
+		}
+
+		out.append("\t\t\t\"geometry\": \"");
+		quote(out, geomtype.c_str());
+		out.append("\",\n");
+
+		size_t attrib_count = layer.second.file_keys.size();
+		if (attrib_count > 1000) {
+			attrib_count = 1000;
+		}
+
+		out.append("\t\t\t\"attributeCount\": ");
+		out.append(std::to_string(attrib_count));
+		out.append(",\n");
+
+		out.append("\t\t\t\"attributes\": [\n");
+
+		size_t attrs = 0;
+		for (auto attribute : layer.second.file_keys) {
+			if (attrs == elements) {
+				break;
+			}
+			if (attrs != 0) {
+				out.append(",\n");
+			}
+			attrs++;
+
+			out.append("\t\t\t\t{\n");
+
+			out.append("\t\t\t\t\t\"attribute\": \"");
+			quote(out, attribute.first.c_str());
+			out.append("\",\n");
+
+			size_t val_count = attribute.second.sample_values.size();
+			if (val_count > 1000) {
+				val_count = 1000;
+			}
+
+			out.append("\t\t\t\t\t\"count\": ");
+			out.append(std::to_string(val_count));
+			out.append(",\n");
+
+			int type = 0;
+			for (auto s : attribute.second.sample_values) {
+				type |= (1 << s.type);
+			}
+
+			std::string type_str;
+			// No "null" because null attributes are dropped
+			if (type == (1 << mvt_double)) {
+				type_str = "number";
+			} else if (type == (1 << mvt_bool)) {
+				type_str = "boolean";
+			} else if (type == (1 << mvt_string)) {
+				type_str = "string";
+			} else {
+				type_str = "mixed";
+			}
+
+			out.append("\t\t\t\t\t\"type\": \"");
+			quote(out, type_str.c_str());
+			out.append("\",\n");
+
+			out.append("\t\t\t\t\t\"values\": [\n");
+
+			size_t vals = 0;
+			for (auto value : attribute.second.sample_values) {
+				if (vals == elements) {
+					break;
+				}
+
+				if (value.type == mvt_double || value.type == mvt_bool) {
+					if (vals != 0) {
+						out.append(",\n");
+					}
+					vals++;
+
+					out.append("\t\t\t\t\t\t");
+					out.append(value.string);
+				} else {
+					std::string trunc = truncate16(value.string, 256);
+
+					if (trunc.size() == value.string.size()) {
+						if (vals != 0) {
+							out.append(",\n");
+						}
+						vals++;
+
+						out.append("\t\t\t\t\t\t\"");
+						quote(out, value.string.c_str());
+						out.append("\"");
+					}
+				}
+			}
+
+			out.append("\n");
+			out.append("\t\t\t\t\t]");
+
+			if ((type & (1 << mvt_double)) != 0) {
+				out.append(",\n");
+
+				out.append("\t\t\t\t\t\"min\": ");
+				out.append(milo::dtoa_milo(attribute.second.min));
+				out.append(",\n");
+
+				out.append("\t\t\t\t\t\"max\": ");
+				out.append(milo::dtoa_milo(attribute.second.max));
+			}
+
+			out.append("\n");
+			out.append("\t\t\t\t}");
+		}
+
+		out.append("\n\t\t\t]\n");
+		out.append("\t\t}");
+	}
+
+	out.append("\n");
+	out.append("\t]\n");
+	out.append("}");
+
+	std::string out2;
+
+	for (size_t i = 0; i < out.size(); i++) {
+		if (out[i] != '\t' && out[i] != '\n') {
+			out2.push_back(out[i]);
+		}
+	}
+
+	return out2;
+}
+
+void mbtiles_write_metadata(sqlite3 *outdb, const char *outdir, const char *fname, int minzoom, int maxzoom, double minlat, double minlon, double maxlat, double maxlon, double midlat, double midlon, int forcetable, const char *attribution, std::map<std::string, layermap_entry> const &layermap, bool vector, const char *description, bool do_tilestats) {
+	char *sql, *err;
+
+	sqlite3 *db = outdb;
+	if (outdb == NULL) {
+		if (sqlite3_open("", &db) != SQLITE_OK) {
+			fprintf(stderr, "Temporary db: %s\n", sqlite3_errmsg(db));
+			exit(EXIT_FAILURE);
+		}
+		if (sqlite3_exec(db, "CREATE TABLE metadata (name text, value text);", NULL, NULL, &err) != SQLITE_OK) {
+			fprintf(stderr, "Create metadata table: %s\n", err);
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('name', %Q);", fname);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set name in metadata: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('description', %Q);", description != NULL ? description : fname);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set description in metadata: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('version', %d);", 2);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set version : %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('minzoom', %d);", minzoom);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set minzoom: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('maxzoom', %d);", maxzoom);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set maxzoom: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('center', '%f,%f,%d');", midlon, midlat, maxzoom);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set center: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('bounds', '%f,%f,%f,%f');", minlon, minlat, maxlon, maxlat);
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set bounds: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('type', %Q);", "overlay");
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set type: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	if (attribution != NULL) {
+		sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('attribution', %Q);", attribution);
+		if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+			fprintf(stderr, "set type: %s\n", err);
+			if (!forcetable) {
+				exit(EXIT_FAILURE);
+			}
+		}
+		sqlite3_free(sql);
+	}
+
+	sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('format', %Q);", vector ? "pbf" : "png");
+	if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "set format: %s\n", err);
+		if (!forcetable) {
+			exit(EXIT_FAILURE);
+		}
+	}
+	sqlite3_free(sql);
+
+	if (vector) {
+		size_t elements = 100;
+		std::string buf;
+
+		{
+			buf = "{";
+			aprintf(&buf, "\"vector_layers\": [ ");
+
+			std::vector<std::string> lnames;
+			for (auto ai = layermap.begin(); ai != layermap.end(); ++ai) {
+				lnames.push_back(ai->first);
+			}
+
+			for (size_t i = 0; i < lnames.size(); i++) {
+				if (i != 0) {
+					aprintf(&buf, ", ");
+				}
+
+				auto fk = layermap.find(lnames[i]);
+				aprintf(&buf, "{ \"id\": \"");
+				quote(buf, lnames[i]);
+				aprintf(&buf, "\", \"description\": \"\", \"minzoom\": %d, \"maxzoom\": %d, \"fields\": {", fk->second.minzoom, fk->second.maxzoom);
+
+				bool first = true;
+				for (auto j = fk->second.file_keys.begin(); j != fk->second.file_keys.end(); ++j) {
+					if (first) {
+						first = false;
+					} else {
+						aprintf(&buf, ", ");
+					}
+
+					aprintf(&buf, "\"");
+					quote(buf, j->first.c_str());
+
+					int type = 0;
+					for (auto s : j->second.sample_values) {
+						type |= (1 << s.type);
+					}
+
+					if (type == (1 << mvt_double)) {
+						aprintf(&buf, "\": \"Number\"");
+					} else if (type == (1 << mvt_bool)) {
+						aprintf(&buf, "\": \"Boolean\"");
+					} else if (type == (1 << mvt_string)) {
+						aprintf(&buf, "\": \"String\"");
+					} else {
+						aprintf(&buf, "\": \"Mixed\"");
+					}
+				}
+
+				aprintf(&buf, "} }");
+			}
+
+			aprintf(&buf, " ]");
+
+			if (do_tilestats && elements > 0) {
+				aprintf(&buf, ",\"tilestats\": %s", tilestats(layermap, elements).c_str());
+			}
+
+			aprintf(&buf, "}");
+		}
+
+		sql = sqlite3_mprintf("INSERT INTO metadata (name, value) VALUES ('json', %Q);", buf.c_str());
+		if (sqlite3_exec(db, sql, NULL, NULL, &err) != SQLITE_OK) {
+			fprintf(stderr, "set json: %s\n", err);
+			if (!forcetable) {
+				exit(EXIT_FAILURE);
+			}
+		}
+		sqlite3_free(sql);
+	}
+
+	if (outdir != NULL) {
+		std::string metadata = std::string(outdir) + "/metadata.json";
+		FILE *fp = fopen(metadata.c_str(), "w");
+		if (fp == NULL) {
+			perror(metadata.c_str());
+			exit(EXIT_FAILURE);
+		}
+
+		fprintf(fp, "{\n");
+
+		sqlite3_stmt *stmt;
+		bool first = true;
+		if (sqlite3_prepare_v2(db, "SELECT name, value from metadata;", -1, &stmt, NULL) == SQLITE_OK) {
+			while (sqlite3_step(stmt) == SQLITE_ROW) {
+				std::string key, value;
+
+				const char *k = (const char *) sqlite3_column_text(stmt, 0);
+				const char *v = (const char *) sqlite3_column_text(stmt, 1);
+				if (k == NULL || v == NULL) {
+					fprintf(stderr, "Corrupt mbtiles file: null metadata\n");
+					exit(EXIT_FAILURE);
+				}
+
+				quote(key, k);
+				quote(value, v);
+
+				if (!first) {
+					fprintf(fp, ",\n");
+				}
+				fprintf(fp, "    \"%s\": \"%s\"", key.c_str(), value.c_str());
+				first = false;
+			}
+			sqlite3_finalize(stmt);
+		}
+
+		fprintf(fp, "\n}\n");
+		fclose(fp);
+	}
+
+	if (outdb == NULL) {
+		if (sqlite3_close(db) != SQLITE_OK) {
+			fprintf(stderr, "Could not close temp database: %s\n", sqlite3_errmsg(db));
+			exit(EXIT_FAILURE);
+		}
+	}
+}
+
+void mbtiles_close(sqlite3 *outdb, const char *pgm) {
+	char *err;
+
+	if (sqlite3_exec(outdb, "ANALYZE;", NULL, NULL, &err) != SQLITE_OK) {
+		fprintf(stderr, "%s: ANALYZE failed: %s\n", pgm, err);
+		exit(EXIT_FAILURE);
+	}
+	if (sqlite3_close(outdb) != SQLITE_OK) {
+		fprintf(stderr, "%s: could not close database: %s\n", pgm, sqlite3_errmsg(outdb));
+		exit(EXIT_FAILURE);
+	}
+}
+
+std::map<std::string, layermap_entry> merge_layermaps(std::vector<std::map<std::string, layermap_entry>> const &maps) {
+	return merge_layermaps(maps, false);
+}
+
+std::map<std::string, layermap_entry> merge_layermaps(std::vector<std::map<std::string, layermap_entry>> const &maps, bool trunc) {
+	std::map<std::string, layermap_entry> out;
+
+	for (size_t i = 0; i < maps.size(); i++) {
+		for (auto map = maps[i].begin(); map != maps[i].end(); ++map) {
+			if (map->second.points + map->second.lines + map->second.polygons == 0) {
+				continue;
+			}
+
+			std::string layername = map->first;
+			if (trunc) {
+				layername = truncate16(layername, 256);
+			}
+
+			if (out.count(layername) == 0) {
+				out.insert(std::pair<std::string, layermap_entry>(layername, layermap_entry(out.size())));
+				auto out_entry = out.find(layername);
+				out_entry->second.minzoom = map->second.minzoom;
+				out_entry->second.maxzoom = map->second.maxzoom;
+			}
+
+			auto out_entry = out.find(layername);
+			if (out_entry == out.end()) {
+				fprintf(stderr, "Internal error merging layers\n");
+				exit(EXIT_FAILURE);
+			}
+
+			for (auto fk = map->second.file_keys.begin(); fk != map->second.file_keys.end(); ++fk) {
+				std::string attribname = fk->first;
+				if (trunc) {
+					attribname = truncate16(attribname, 256);
+				}
+
+				auto fk2 = out_entry->second.file_keys.find(attribname);
+
+				if (fk2 == out_entry->second.file_keys.end()) {
+					out_entry->second.file_keys.insert(std::pair<std::string, type_and_string_stats>(attribname, fk->second));
+				} else {
+					for (auto val : fk->second.sample_values) {
+						auto pt = std::lower_bound(fk2->second.sample_values.begin(), fk2->second.sample_values.end(), val);
+						if (pt == fk2->second.sample_values.end() || *pt != val) {  // not found
+							fk2->second.sample_values.insert(pt, val);
+
+							if (fk2->second.sample_values.size() > 1000) {
+								fk2->second.sample_values.pop_back();
+							}
+						}
+					}
+
+					fk2->second.type |= fk->second.type;
+
+					if (fk->second.min < fk2->second.min) {
+						fk2->second.min = fk->second.min;
+					}
+					if (fk->second.max > fk2->second.max) {
+						fk2->second.max = fk->second.max;
+					}
+				}
+			}
+
+			if (map->second.minzoom < out_entry->second.minzoom) {
+				out_entry->second.minzoom = map->second.minzoom;
+			}
+			if (map->second.maxzoom > out_entry->second.maxzoom) {
+				out_entry->second.maxzoom = map->second.maxzoom;
+			}
+
+			out_entry->second.points += map->second.points;
+			out_entry->second.lines += map->second.lines;
+			out_entry->second.polygons += map->second.polygons;
+		}
+	}
+
+	return out;
+}
+
+void add_to_file_keys(std::map<std::string, type_and_string_stats> &file_keys, std::string const &attrib, type_and_string const &val) {
+	auto fka = file_keys.find(attrib);
+	if (fka == file_keys.end()) {
+		file_keys.insert(std::pair<std::string, type_and_string_stats>(attrib, type_and_string_stats()));
+		fka = file_keys.find(attrib);
+	}
+
+	if (fka == file_keys.end()) {
+		fprintf(stderr, "Can't happen (tilestats)\n");
+		exit(EXIT_FAILURE);
+	}
+
+	if (val.type == mvt_double) {
+		double d = atof(val.string.c_str());
+
+		if (d < fka->second.min) {
+			fka->second.min = d;
+		}
+		if (d > fka->second.max) {
+			fka->second.max = d;
+		}
+	}
+
+	auto pt = std::lower_bound(fka->second.sample_values.begin(), fka->second.sample_values.end(), val);
+	if (pt == fka->second.sample_values.end() || *pt != val) {  // not found
+		fka->second.sample_values.insert(pt, val);
+
+		if (fka->second.sample_values.size() > 1000) {
+			fka->second.sample_values.pop_back();
+		}
+	}
+
+	fka->second.type |= (1 << val.type);
+}

mbtiles.h

@@ -1,7 +0,0 @@
-sqlite3 *mbtiles_open(char *dbname, char **argv);
-
-void mbtiles_write_tile(sqlite3 *outdb, int z, int tx, int ty, const char *data, int size);
-
-void mbtiles_write_metadata(sqlite3 *outdb, const char *fname, char **layername, int minzoom, int maxzoom, double minlat, double minlon, double maxlat, double maxlon, double midlat, double midlon, struct pool **file_keys, int nlayers);
-
-void mbtiles_close(sqlite3 *outdb, char **argv);

mbtiles.hpp

@@ -0,0 +1,53 @@
+#ifndef MBTILES_HPP
+#define MBTILES_HPP
+
+#include <math.h>
+#include <map>
+#include "mvt.hpp"
+
+struct type_and_string {
+	int type;
+	std::string string;
+
+	bool operator<(const type_and_string &o) const;
+	bool operator!=(const type_and_string &o) const;
+};
+
+struct type_and_string_stats {
+	std::vector<type_and_string> sample_values;  // sorted
+	double min = INFINITY;
+	double max = -INFINITY;
+	int type = 0;
+};
+
+struct layermap_entry {
+	size_t id;
+	std::map<std::string, type_and_string_stats> file_keys;
+	int minzoom;
+	int maxzoom;
+
+	size_t points = 0;
+	size_t lines = 0;
+	size_t polygons = 0;
+
+	layermap_entry(size_t _id) {
+		id = _id;
+	}
+};
+
+sqlite3 *mbtiles_open(char *dbname, char **argv, int forcetable);
+
+void mbtiles_write_tile(sqlite3 *outdb, int z, int tx, int ty, const char *data, int size);
+
+void mbtiles_write_metadata(sqlite3 *outdb, const char *outdir, const char *fname, int minzoom, int maxzoom, double minlat, double minlon, double maxlat, double maxlon, double midlat, double midlon, int forcetable, const char *attribution, std::map<std::string, layermap_entry> const &layermap, bool vector, const char *description, bool do_tilestats);
+
+void mbtiles_close(sqlite3 *outdb, const char *pgm);
+
+void aprintf(std::string *buf, const char *format, ...);
+
+std::map<std::string, layermap_entry> merge_layermaps(std::vector<std::map<std::string, layermap_entry> > const &maps);
+std::map<std::string, layermap_entry> merge_layermaps(std::vector<std::map<std::string, layermap_entry> > const &maps, bool trunc);
+
+void add_to_file_keys(std::map<std::string, type_and_string_stats> &file_keys, std::string const &layername, type_and_string const &val);
+
+#endif

memfile.cpp

@@ -2,30 +2,32 @@
 #include <string.h>
 #include <unistd.h>
 #include <sys/mman.h>
-#include "memfile.h"
+#include "memfile.hpp"
 
 #define INCREMENT 131072
+#define INITIAL 256
 
 struct memfile *memfile_open(int fd) {
-	if (ftruncate(fd, INCREMENT) != 0) {
+	if (ftruncate(fd, INITIAL) != 0) {
 		return NULL;
 	}
 
-	char *map = mmap(NULL, INCREMENT, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	char *map = (char *) mmap(NULL, INITIAL, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 	if (map == MAP_FAILED) {
 		return NULL;
 	}
 
-	struct memfile *mf = malloc(sizeof(struct memfile));
+	struct memfile *mf = new memfile;
 	if (mf == NULL) {
-		munmap(map, INCREMENT);
+		munmap(map, INITIAL);
 		return NULL;
 	}
 
 	mf->fd = fd;
 	mf->map = map;
-	mf->len = INCREMENT;
+	mf->len = INITIAL;
 	mf->off = 0;
+	mf->tree = 0;
 
 	return mf;
 }
@@ -41,7 +43,7 @@ int memfile_close(struct memfile *file) {
 		}
 	}
 
-	free(file);
+	delete file;
 	return 0;
 }
 
@@ -51,13 +53,13 @@ int memfile_write(struct memfile *file, void *s, long long len) {
 			return -1;
 		}
 
-		file->len += INCREMENT;
+		file->len += (len + INCREMENT + 1) / INCREMENT * INCREMENT;
 
 		if (ftruncate(file->fd, file->len) != 0) {
 			return -1;
 		}
 
-		file->map = mmap(NULL, file->len, PROT_READ | PROT_WRITE, MAP_SHARED, file->fd, 0);
+		file->map = (char *) mmap(NULL, file->len, PROT_READ | PROT_WRITE, MAP_SHARED, file->fd, 0);
 		if (file->map == MAP_FAILED) {
 			return -1;
 		}

memfile.hpp

@@ -1,10 +1,16 @@
+#ifndef MEMFILE_HPP
+#define MEMFILE_HPP
+
 struct memfile {
 	int fd;
 	char *map;
 	long long len;
 	long long off;
+	unsigned long tree;
 };
 
 struct memfile *memfile_open(int fd);
 int memfile_close(struct memfile *file);
 int memfile_write(struct memfile *file, void *s, long long len);
+
+#endif

milo/LICENSE.txt

@@ -0,0 +1,19 @@
+Copyright (C) 2014 Milo Yip
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

milo/dtoa_milo.h

@@ -0,0 +1,414 @@
+#pragma once
+#include <assert.h>
+#include <math.h>
+#include <cmath>
+
+#if defined(_MSC_VER)
+#include "msinttypes/stdint.h"
+#include <intrin.h>
+#else
+#include <stdint.h>
+#endif
+
+namespace milo {
+
+#define UINT64_C2(h, l) ((static_cast<uint64_t>(h) << 32) | static_cast<uint64_t>(l))
+
+struct DiyFp {
+	DiyFp() {}
+
+	DiyFp(uint64_t ff, int ee) : f(ff), e(ee) {}
+
+	DiyFp(double d) {
+		union {
+			double d;
+			uint64_t u64;
+		} u = { d };
+
+		int biased_e = (u.u64 & kDpExponentMask) >> kDpSignificandSize;
+		uint64_t significand = (u.u64 & kDpSignificandMask);
+		if (biased_e != 0) {
+			f = significand + kDpHiddenBit;
+			e = biased_e - kDpExponentBias;
+		} 
+		else {
+			f = significand;
+			e = kDpMinExponent + 1;
+		}
+	}
+
+	DiyFp operator-(const DiyFp& rhs) const {
+		assert(e == rhs.e);
+		assert(f >= rhs.f);
+		return DiyFp(f - rhs.f, e);
+	}
+
+	DiyFp operator*(const DiyFp& rhs) const {
+#if defined(_MSC_VER) && defined(_M_AMD64)
+		uint64_t h;
+		uint64_t l = _umul128(f, rhs.f, &h);
+		if (l & (uint64_t(1) << 63)) // rounding
+			h++;
+		return DiyFp(h, e + rhs.e + 64);
+#elif (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) && defined(__x86_64__)
+		unsigned __int128 p = static_cast<unsigned __int128>(f) * static_cast<unsigned __int128>(rhs.f);
+		uint64_t h = p >> 64;
+		uint64_t l = static_cast<uint64_t>(p);
+		if (l & (uint64_t(1) << 63)) // rounding
+			h++;
+		return DiyFp(h, e + rhs.e + 64);
+#else
+		const uint64_t M32 = 0xFFFFFFFF;
+		const uint64_t a = f >> 32;
+		const uint64_t b = f & M32;
+		const uint64_t c = rhs.f >> 32;
+		const uint64_t d = rhs.f & M32;
+		const uint64_t ac = a * c;
+		const uint64_t bc = b * c;
+		const uint64_t ad = a * d;
+		const uint64_t bd = b * d;
+		uint64_t tmp = (bd >> 32) + (ad & M32) + (bc & M32);
+		tmp += 1U << 31;  /// mult_round
+		return DiyFp(ac + (ad >> 32) + (bc >> 32) + (tmp >> 32), e + rhs.e + 64);
+#endif
+	}
+
+	DiyFp Normalize() const {
+#if defined(_MSC_VER) && defined(_M_AMD64)
+		unsigned long index;
+		_BitScanReverse64(&index, f);
+		return DiyFp(f << (63 - index), e - (63 - index));
+#elif defined(__GNUC__)
+		int s = __builtin_clzll(f);
+		return DiyFp(f << s, e - s);
+#else
+		DiyFp res = *this;
+		while (!(res.f & kDpHiddenBit)) {
+			res.f <<= 1;
+			res.e--;
+		}
+		res.f <<= (kDiySignificandSize - kDpSignificandSize - 1);
+		res.e = res.e - (kDiySignificandSize - kDpSignificandSize - 1);
+		return res;
+#endif
+	}
+
+	DiyFp NormalizeBoundary() const {
+#if defined(_MSC_VER) && defined(_M_AMD64)
+		unsigned long index;
+		_BitScanReverse64(&index, f);
+		return DiyFp (f << (63 - index), e - (63 - index));
+#else
+		DiyFp res = *this;
+		while (!(res.f & (kDpHiddenBit << 1))) {
+			res.f <<= 1;
+			res.e--;
+		}
+		res.f <<= (kDiySignificandSize - kDpSignificandSize - 2);
+		res.e = res.e - (kDiySignificandSize - kDpSignificandSize - 2);
+		return res;
+#endif
+	}
+
+	void NormalizedBoundaries(DiyFp* minus, DiyFp* plus) const {
+		DiyFp pl = DiyFp((f << 1) + 1, e - 1).NormalizeBoundary();
+		DiyFp mi = (f == kDpHiddenBit) ? DiyFp((f << 2) - 1, e - 2) : DiyFp((f << 1) - 1, e - 1);
+		mi.f <<= mi.e - pl.e;
+		mi.e = pl.e;
+		*plus = pl;
+		*minus = mi;
+	}
+
+	static const int kDiySignificandSize = 64;
+	static const int kDpSignificandSize = 52;
+	static const int kDpExponentBias = 0x3FF + kDpSignificandSize;
+	static const int kDpMinExponent = -kDpExponentBias;
+	static const uint64_t kDpExponentMask = UINT64_C2(0x7FF00000, 0x00000000);
+	static const uint64_t kDpSignificandMask = UINT64_C2(0x000FFFFF, 0xFFFFFFFF);
+	static const uint64_t kDpHiddenBit = UINT64_C2(0x00100000, 0x00000000);
+
+	uint64_t f;
+	int e;
+};
+
+inline DiyFp GetCachedPower(int e, int* K) {
+	// 10^-348, 10^-340, ..., 10^340
+	static const uint64_t kCachedPowers_F[] = {
+		UINT64_C2(0xfa8fd5a0, 0x081c0288), UINT64_C2(0xbaaee17f, 0xa23ebf76),
+		UINT64_C2(0x8b16fb20, 0x3055ac76), UINT64_C2(0xcf42894a, 0x5dce35ea),
+		UINT64_C2(0x9a6bb0aa, 0x55653b2d), UINT64_C2(0xe61acf03, 0x3d1a45df),
+		UINT64_C2(0xab70fe17, 0xc79ac6ca), UINT64_C2(0xff77b1fc, 0xbebcdc4f),
+		UINT64_C2(0xbe5691ef, 0x416bd60c), UINT64_C2(0x8dd01fad, 0x907ffc3c),
+		UINT64_C2(0xd3515c28, 0x31559a83), UINT64_C2(0x9d71ac8f, 0xada6c9b5),
+		UINT64_C2(0xea9c2277, 0x23ee8bcb), UINT64_C2(0xaecc4991, 0x4078536d),
+		UINT64_C2(0x823c1279, 0x5db6ce57), UINT64_C2(0xc2109436, 0x4dfb5637),
+		UINT64_C2(0x9096ea6f, 0x3848984f), UINT64_C2(0xd77485cb, 0x25823ac7),
+		UINT64_C2(0xa086cfcd, 0x97bf97f4), UINT64_C2(0xef340a98, 0x172aace5),
+		UINT64_C2(0xb23867fb, 0x2a35b28e), UINT64_C2(0x84c8d4df, 0xd2c63f3b),
+		UINT64_C2(0xc5dd4427, 0x1ad3cdba), UINT64_C2(0x936b9fce, 0xbb25c996),
+		UINT64_C2(0xdbac6c24, 0x7d62a584), UINT64_C2(0xa3ab6658, 0x0d5fdaf6),
+		UINT64_C2(0xf3e2f893, 0xdec3f126), UINT64_C2(0xb5b5ada8, 0xaaff80b8),
+		UINT64_C2(0x87625f05, 0x6c7c4a8b), UINT64_C2(0xc9bcff60, 0x34c13053),
+		UINT64_C2(0x964e858c, 0x91ba2655), UINT64_C2(0xdff97724, 0x70297ebd),
+		UINT64_C2(0xa6dfbd9f, 0xb8e5b88f), UINT64_C2(0xf8a95fcf, 0x88747d94),
+		UINT64_C2(0xb9447093, 0x8fa89bcf), UINT64_C2(0x8a08f0f8, 0xbf0f156b),
+		UINT64_C2(0xcdb02555, 0x653131b6), UINT64_C2(0x993fe2c6, 0xd07b7fac),
+		UINT64_C2(0xe45c10c4, 0x2a2b3b06), UINT64_C2(0xaa242499, 0x697392d3),
+		UINT64_C2(0xfd87b5f2, 0x8300ca0e), UINT64_C2(0xbce50864, 0x92111aeb),
+		UINT64_C2(0x8cbccc09, 0x6f5088cc), UINT64_C2(0xd1b71758, 0xe219652c),
+		UINT64_C2(0x9c400000, 0x00000000), UINT64_C2(0xe8d4a510, 0x00000000),
+		UINT64_C2(0xad78ebc5, 0xac620000), UINT64_C2(0x813f3978, 0xf8940984),
+		UINT64_C2(0xc097ce7b, 0xc90715b3), UINT64_C2(0x8f7e32ce, 0x7bea5c70),
+		UINT64_C2(0xd5d238a4, 0xabe98068), UINT64_C2(0x9f4f2726, 0x179a2245),
+		UINT64_C2(0xed63a231, 0xd4c4fb27), UINT64_C2(0xb0de6538, 0x8cc8ada8),
+		UINT64_C2(0x83c7088e, 0x1aab65db), UINT64_C2(0xc45d1df9, 0x42711d9a),
+		UINT64_C2(0x924d692c, 0xa61be758), UINT64_C2(0xda01ee64, 0x1a708dea),
+		UINT64_C2(0xa26da399, 0x9aef774a), UINT64_C2(0xf209787b, 0xb47d6b85),
+		UINT64_C2(0xb454e4a1, 0x79dd1877), UINT64_C2(0x865b8692, 0x5b9bc5c2),
+		UINT64_C2(0xc83553c5, 0xc8965d3d), UINT64_C2(0x952ab45c, 0xfa97a0b3),
+		UINT64_C2(0xde469fbd, 0x99a05fe3), UINT64_C2(0xa59bc234, 0xdb398c25),
+		UINT64_C2(0xf6c69a72, 0xa3989f5c), UINT64_C2(0xb7dcbf53, 0x54e9bece),
+		UINT64_C2(0x88fcf317, 0xf22241e2), UINT64_C2(0xcc20ce9b, 0xd35c78a5),
+		UINT64_C2(0x98165af3, 0x7b2153df), UINT64_C2(0xe2a0b5dc, 0x971f303a),
+		UINT64_C2(0xa8d9d153, 0x5ce3b396), UINT64_C2(0xfb9b7cd9, 0xa4a7443c),
+		UINT64_C2(0xbb764c4c, 0xa7a44410), UINT64_C2(0x8bab8eef, 0xb6409c1a),
+		UINT64_C2(0xd01fef10, 0xa657842c), UINT64_C2(0x9b10a4e5, 0xe9913129),
+		UINT64_C2(0xe7109bfb, 0xa19c0c9d), UINT64_C2(0xac2820d9, 0x623bf429),
+		UINT64_C2(0x80444b5e, 0x7aa7cf85), UINT64_C2(0xbf21e440, 0x03acdd2d),
+		UINT64_C2(0x8e679c2f, 0x5e44ff8f), UINT64_C2(0xd433179d, 0x9c8cb841),
+		UINT64_C2(0x9e19db92, 0xb4e31ba9), UINT64_C2(0xeb96bf6e, 0xbadf77d9),
+		UINT64_C2(0xaf87023b, 0x9bf0ee6b)
+	};
+	static const int16_t kCachedPowers_E[] = {
+		-1220, -1193, -1166, -1140, -1113, -1087, -1060, -1034, -1007,  -980,
+		 -954,  -927,  -901,  -874,  -847,  -821,  -794,  -768,  -741,  -715,
+		 -688,  -661,  -635,  -608,  -582,  -555,  -529,  -502,  -475,  -449,
+		 -422,  -396,  -369,  -343,  -316,  -289,  -263,  -236,  -210,  -183,
+		 -157,  -130,  -103,   -77,   -50,   -24,     3,    30,    56,    83,
+		  109,   136,   162,   189,   216,   242,   269,   295,   322,   348,
+		  375,   402,   428,   455,   481,   508,   534,   561,   588,   614,
+		  641,   667,   694,   720,   747,   774,   800,   827,   853,   880,
+		  907,   933,   960,   986,  1013,  1039,  1066
+	};
+
+	//int k = static_cast<int>(ceil((-61 - e) * 0.30102999566398114)) + 374;
+	double dk = (-61 - e) * 0.30102999566398114 + 347;	// dk must be positive, so can do ceiling in positive
+	int k = static_cast<int>(dk);
+	if (k != dk)
+		k++;
+
+	unsigned index = static_cast<unsigned>((k >> 3) + 1);
+	*K = -(-348 + static_cast<int>(index << 3));	// decimal exponent no need lookup table
+
+	assert(index < sizeof(kCachedPowers_F) / sizeof(kCachedPowers_F[0]));
+	return DiyFp(kCachedPowers_F[index], kCachedPowers_E[index]);
+}
+
+inline void GrisuRound(std::string &buffer, int len, uint64_t delta, uint64_t rest, uint64_t ten_kappa, uint64_t wp_w) {
+	while (rest < wp_w && delta - rest >= ten_kappa &&
+		   (rest + ten_kappa < wp_w ||  /// closer
+			wp_w - rest > rest + ten_kappa - wp_w)) {
+		buffer[len - 1]--;
+		rest += ten_kappa;
+	}
+}
+
+inline unsigned CountDecimalDigit32(uint32_t n) {
+	// Simple pure C++ implementation was faster than __builtin_clz version in this situation.
+	if (n < 10) return 1;
+	if (n < 100) return 2;
+	if (n < 1000) return 3;
+	if (n < 10000) return 4;
+	if (n < 100000) return 5;
+	if (n < 1000000) return 6;
+	if (n < 10000000) return 7;
+	if (n < 100000000) return 8;
+	if (n < 1000000000) return 9;
+	return 10;
+}
+
+inline void DigitGen(const DiyFp& W, const DiyFp& Mp, uint64_t delta, std::string &buffer, int* len, int* K) {
+	static const uint32_t kPow10[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000 };
+	const DiyFp one(uint64_t(1) << -Mp.e, Mp.e);
+	const DiyFp wp_w = Mp - W;
+	uint32_t p1 = static_cast<uint32_t>(Mp.f >> -one.e);
+	uint64_t p2 = Mp.f & (one.f - 1);
+	int kappa = static_cast<int>(CountDecimalDigit32(p1));
+	*len = 0;
+
+	while (kappa > 0) {
+		uint32_t d;
+		switch (kappa) {
+			case 10: d = p1 / 1000000000; p1 %= 1000000000; break;
+			case  9: d = p1 /  100000000; p1 %=  100000000; break;
+			case  8: d = p1 /   10000000; p1 %=   10000000; break;
+			case  7: d = p1 /    1000000; p1 %=    1000000; break;
+			case  6: d = p1 /     100000; p1 %=     100000; break;
+			case  5: d = p1 /      10000; p1 %=      10000; break;
+			case  4: d = p1 /       1000; p1 %=       1000; break;
+			case  3: d = p1 /        100; p1 %=        100; break;
+			case  2: d = p1 /         10; p1 %=         10; break;
+			case  1: d = p1;              p1 =           0; break;
+			default: 
+#if defined(_MSC_VER)
+				__assume(0);
+#elif __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
+				__builtin_unreachable();
+#else
+				d = 0;
+#endif
+		}
+		if (d || *len) {
+			buffer.push_back('0' + static_cast<char>(d));
+			(*len)++;
+		}
+		kappa--;
+		uint64_t tmp = (static_cast<uint64_t>(p1) << -one.e) + p2;
+		if (tmp <= delta) {
+			*K += kappa;
+			GrisuRound(buffer, *len, delta, tmp, static_cast<uint64_t>(kPow10[kappa]) << -one.e, wp_w.f);
+			return;
+		}
+	}
+
+	// kappa = 0
+	for (;;) {
+		p2 *= 10;
+		delta *= 10;
+		char d = static_cast<char>(p2 >> -one.e);
+		if (d || *len) {
+			buffer.push_back('0' + d);
+			(*len)++;
+		}
+		p2 &= one.f - 1;
+		kappa--;
+		if (p2 < delta) {
+			*K += kappa;
+			GrisuRound(buffer, *len, delta, p2, one.f, wp_w.f * kPow10[-kappa]);
+			return;
+		}
+	}
+}
+
+inline void Grisu2(double value, std::string &buffer, int* length, int* K) {
+	const DiyFp v(value);
+	DiyFp w_m, w_p;
+	v.NormalizedBoundaries(&w_m, &w_p);
+
+	const DiyFp c_mk = GetCachedPower(w_p.e, K);
+	const DiyFp W = v.Normalize() * c_mk;
+	DiyFp Wp = w_p * c_mk;
+	DiyFp Wm = w_m * c_mk;
+	Wm.f++;
+	Wp.f--;
+	DigitGen(W, Wp, Wp.f - Wm.f, buffer, length, K);
+}
+
+inline const char* GetDigitsLut() {
+	static const char cDigitsLut[200] = {
+		'0', '0', '0', '1', '0', '2', '0', '3', '0', '4', '0', '5', '0', '6', '0', '7', '0', '8', '0', '9',
+		'1', '0', '1', '1', '1', '2', '1', '3', '1', '4', '1', '5', '1', '6', '1', '7', '1', '8', '1', '9',
+		'2', '0', '2', '1', '2', '2', '2', '3', '2', '4', '2', '5', '2', '6', '2', '7', '2', '8', '2', '9',
+		'3', '0', '3', '1', '3', '2', '3', '3', '3', '4', '3', '5', '3', '6', '3', '7', '3', '8', '3', '9',
+		'4', '0', '4', '1', '4', '2', '4', '3', '4', '4', '4', '5', '4', '6', '4', '7', '4', '8', '4', '9',
+		'5', '0', '5', '1', '5', '2', '5', '3', '5', '4', '5', '5', '5', '6', '5', '7', '5', '8', '5', '9',
+		'6', '0', '6', '1', '6', '2', '6', '3', '6', '4', '6', '5', '6', '6', '6', '7', '6', '8', '6', '9',
+		'7', '0', '7', '1', '7', '2', '7', '3', '7', '4', '7', '5', '7', '6', '7', '7', '7', '8', '7', '9',
+		'8', '0', '8', '1', '8', '2', '8', '3', '8', '4', '8', '5', '8', '6', '8', '7', '8', '8', '8', '9',
+		'9', '0', '9', '1', '9', '2', '9', '3', '9', '4', '9', '5', '9', '6', '9', '7', '9', '8', '9', '9'
+	};
+	return cDigitsLut;
+}
+
+inline void WriteExponent(int K, std::string &buffer) {
+	if (K < 0) {
+		buffer.push_back('-');
+		K = -K;
+	} else {
+		buffer.push_back('+');
+	}
+
+	if (K >= 100) {
+		buffer.push_back('0' + static_cast<char>(K / 100));
+		K %= 100;
+		const char* d = GetDigitsLut() + K * 2;
+		buffer.push_back(d[0]);
+		buffer.push_back(d[1]);
+	}
+	else if (K >= 10) {
+		const char* d = GetDigitsLut() + K * 2;
+		buffer.push_back(d[0]);
+		buffer.push_back(d[1]);
+	}
+	else
+		buffer.push_back('0' + static_cast<char>(K));
+}
+
+inline void Prettify(std::string &buffer, int length, int k) {
+	const int kk = length + k;	// 10^(kk-1) <= v < 10^kk
+
+	if (length <= kk && kk <= 21) {
+		// 1234e7 -> 12340000000
+		for (int i = length; i < kk; i++)
+			buffer.push_back('0');
+	}
+	else if (0 < kk && kk <= 21) {
+		// 1234e-2 -> 12.34
+		buffer.insert(buffer.begin() + kk, '.');
+	}
+	else if (-6 < kk && kk <= 0) {
+		// 1234e-6 -> 0.001234
+		const int offset = 2 - kk;
+		buffer.insert(buffer.begin(), '0');
+		buffer.insert(buffer.begin() + 1, '.');
+		for (int i = 2; i < offset; i++)
+			buffer.insert(buffer.begin() + 2, '0');
+	}
+	else if (length == 1) {
+		// 1e30
+		buffer.push_back('e');
+		WriteExponent(kk - 1, buffer);
+	}
+	else {
+		// 1234e30 -> 1.234e33
+		buffer.insert(buffer.begin() + 1, '.');
+		buffer.push_back('e');
+		WriteExponent(kk - 1, buffer);
+	}
+}
+
+inline std::string dtoa_milo(double value) {
+	std::string buffer;
+
+	if (std::isnan(value)) {
+		return "nan";
+	}
+	if (std::isinf(value)) {
+		if (value < 0) {
+			return "-inf";
+		} else {
+			return "inf";
+		}
+	}
+
+	if (value == 0) {
+		buffer = "0";
+	}
+	else {
+		bool minus = false;
+		if (value < 0) {
+			minus = true;
+			value = -value;
+		}
+		int length, K;
+		Grisu2(value, buffer, &length, &K);
+		Prettify(buffer, length, K);
+		if (minus) {
+			buffer.insert(buffer.begin(), '-');
+		}
+	}
+
+	return buffer;
+}
+
+}

mvt.cpp

@@ -0,0 +1,541 @@
+#include <stdio.h>
+#include <string.h>
+#include <string>
+#include <vector>
+#include <map>
+#include <zlib.h>
+#include <errno.h>
+#include <limits.h>
+#include "mvt.hpp"
+#include "geometry.hpp"
+#include "protozero/varint.hpp"
+#include "protozero/pbf_reader.hpp"
+#include "protozero/pbf_writer.hpp"
+#include "milo/dtoa_milo.h"
+
+mvt_geometry::mvt_geometry(int nop, long long nx, long long ny) {
+	this->op = nop;
+	this->x = nx;
+	this->y = ny;
+}
+
+// https://github.com/mapbox/mapnik-vector-tile/blob/master/src/vector_tile_compression.hpp
+bool is_compressed(std::string const &data) {
+	return data.size() > 2 && (((uint8_t) data[0] == 0x78 && (uint8_t) data[1] == 0x9C) || ((uint8_t) data[0] == 0x1F && (uint8_t) data[1] == 0x8B));
+}
+
+// https://github.com/mapbox/mapnik-vector-tile/blob/master/src/vector_tile_compression.hpp
+int decompress(std::string const &input, std::string &output) {
+	z_stream inflate_s;
+	inflate_s.zalloc = Z_NULL;
+	inflate_s.zfree = Z_NULL;
+	inflate_s.opaque = Z_NULL;
+	inflate_s.avail_in = 0;
+	inflate_s.next_in = Z_NULL;
+	if (inflateInit2(&inflate_s, 32 + 15) != Z_OK) {
+		fprintf(stderr, "error: %s\n", inflate_s.msg);
+	}
+	inflate_s.next_in = (Bytef *) input.data();
+	inflate_s.avail_in = input.size();
+	size_t length = 0;
+	do {
+		output.resize(length + 2 * input.size());
+		inflate_s.avail_out = 2 * input.size();
+		inflate_s.next_out = (Bytef *) (output.data() + length);
+		int ret = inflate(&inflate_s, Z_FINISH);
+		if (ret != Z_STREAM_END && ret != Z_OK && ret != Z_BUF_ERROR) {
+			fprintf(stderr, "error: %s\n", inflate_s.msg);
+			return 0;
+		}
+
+		length += (2 * input.size() - inflate_s.avail_out);
+	} while (inflate_s.avail_out == 0);
+	inflateEnd(&inflate_s);
+	output.resize(length);
+	return 1;
+}
+
+// https://github.com/mapbox/mapnik-vector-tile/blob/master/src/vector_tile_compression.hpp
+int compress(std::string const &input, std::string &output) {
+	z_stream deflate_s;
+	deflate_s.zalloc = Z_NULL;
+	deflate_s.zfree = Z_NULL;
+	deflate_s.opaque = Z_NULL;
+	deflate_s.avail_in = 0;
+	deflate_s.next_in = Z_NULL;
+	deflateInit2(&deflate_s, Z_BEST_COMPRESSION, Z_DEFLATED, 31, 8, Z_DEFAULT_STRATEGY);
+	deflate_s.next_in = (Bytef *) input.data();
+	deflate_s.avail_in = input.size();
+	size_t length = 0;
+	do {
+		size_t increase = input.size() / 2 + 1024;
+		output.resize(length + increase);
+		deflate_s.avail_out = increase;
+		deflate_s.next_out = (Bytef *) (output.data() + length);
+		int ret = deflate(&deflate_s, Z_FINISH);
+		if (ret != Z_STREAM_END && ret != Z_OK && ret != Z_BUF_ERROR) {
+			return -1;
+		}
+		length += (increase - deflate_s.avail_out);
+	} while (deflate_s.avail_out == 0);
+	deflateEnd(&deflate_s);
+	output.resize(length);
+	return 0;
+}
+
+bool mvt_tile::decode(std::string &message, bool &was_compressed) {
+	layers.clear();
+	std::string src;
+
+	if (is_compressed(message)) {
+		std::string uncompressed;
+		decompress(message, uncompressed);
+		src = uncompressed;
+		was_compressed = true;
+	} else {
+		src = message;
+		was_compressed = false;
+	}
+
+	protozero::pbf_reader reader(src);
+
+	while (reader.next()) {
+		switch (reader.tag()) {
+		case 3: /* layer */
+		{
+			protozero::pbf_reader layer_reader(reader.get_message());
+			mvt_layer layer;
+
+			while (layer_reader.next()) {
+				switch (layer_reader.tag()) {
+				case 1: /* name */
+					layer.name = layer_reader.get_string();
+					break;
+
+				case 3: /* key */
+					layer.keys.push_back(layer_reader.get_string());
+					break;
+
+				case 4: /* value */
+				{
+					protozero::pbf_reader value_reader(layer_reader.get_message());
+					mvt_value value;
+
+					while (value_reader.next()) {
+						switch (value_reader.tag()) {
+						case 1: /* string */
+							value.type = mvt_string;
+							value.string_value = value_reader.get_string();
+							break;
+
+						case 2: /* float */
+							value.type = mvt_float;
+							value.numeric_value.float_value = value_reader.get_float();
+							break;
+
+						case 3: /* double */
+							value.type = mvt_double;
+							value.numeric_value.double_value = value_reader.get_double();
+							break;
+
+						case 4: /* int */
+							value.type = mvt_int;
+							value.numeric_value.int_value = value_reader.get_int64();
+							break;
+
+						case 5: /* uint */
+							value.type = mvt_uint;
+							value.numeric_value.uint_value = value_reader.get_uint64();
+							break;
+
+						case 6: /* sint */
+							value.type = mvt_sint;
+							value.numeric_value.sint_value = value_reader.get_sint64();
+							break;
+
+						case 7: /* bool */
+							value.type = mvt_bool;
+							value.numeric_value.bool_value = value_reader.get_bool();
+							break;
+
+						default:
+							value_reader.skip();
+							break;
+						}
+					}
+
+					layer.values.push_back(value);
+					break;
+				}
+
+				case 5: /* extent */
+					layer.extent = layer_reader.get_uint32();
+					break;
+
+				case 15: /* version */
+					layer.version = layer_reader.get_uint32();
+					break;
+
+				case 2: /* feature */
+				{
+					protozero::pbf_reader feature_reader(layer_reader.get_message());
+					mvt_feature feature;
+					std::vector<uint32_t> geoms;
+
+					while (feature_reader.next()) {
+						switch (feature_reader.tag()) {
+						case 1: /* id */
+							feature.id = feature_reader.get_uint64();
+							feature.has_id = true;
+							break;
+
+						case 2: /* tag */
+						{
+							auto pi = feature_reader.get_packed_uint32();
+							for (auto it = pi.first; it != pi.second; ++it) {
+								feature.tags.push_back(*it);
+							}
+							break;
+						}
+
+						case 3: /* feature type */
+							feature.type = feature_reader.get_enum();
+							break;
+
+						case 4: /* geometry */
+						{
+							auto pi = feature_reader.get_packed_uint32();
+							for (auto it = pi.first; it != pi.second; ++it) {
+								geoms.push_back(*it);
+							}
+							break;
+						}
+
+						default:
+							feature_reader.skip();
+							break;
+						}
+					}
+
+					long long px = 0, py = 0;
+					for (size_t g = 0; g < geoms.size(); g++) {
+						uint32_t geom = geoms[g];
+						uint32_t op = geom & 7;
+						uint32_t count = geom >> 3;
+
+						if (op == mvt_moveto || op == mvt_lineto) {
+							for (size_t k = 0; k < count && g + 2 < geoms.size(); k++) {
+								px += protozero::decode_zigzag32(geoms[g + 1]);
+								py += protozero::decode_zigzag32(geoms[g + 2]);
+								g += 2;
+
+								feature.geometry.push_back(mvt_geometry(op, px, py));
+							}
+						} else {
+							feature.geometry.push_back(mvt_geometry(op, 0, 0));
+						}
+					}
+
+					layer.features.push_back(feature);
+					break;
+				}
+
+				default:
+					layer_reader.skip();
+					break;
+				}
+			}
+
+			for (size_t i = 0; i < layer.keys.size(); i++) {
+				layer.key_map.insert(std::pair<std::string, size_t>(layer.keys[i], i));
+			}
+			for (size_t i = 0; i < layer.values.size(); i++) {
+				layer.value_map.insert(std::pair<mvt_value, size_t>(layer.values[i], i));
+			}
+
+			layers.push_back(layer);
+			break;
+		}
+
+		default:
+			reader.skip();
+			break;
+		}
+	}
+
+	return true;
+}
+
+std::string mvt_tile::encode() {
+	std::string data;
+
+	protozero::pbf_writer writer(data);
+
+	for (size_t i = 0; i < layers.size(); i++) {
+		std::string layer_string;
+		protozero::pbf_writer layer_writer(layer_string);
+
+		layer_writer.add_uint32(15, layers[i].version); /* version */
+		layer_writer.add_string(1, layers[i].name);     /* name */
+		layer_writer.add_uint32(5, layers[i].extent);   /* extent */
+
+		for (size_t j = 0; j < layers[i].keys.size(); j++) {
+			layer_writer.add_string(3, layers[i].keys[j]); /* key */
+		}
+
+		for (size_t v = 0; v < layers[i].values.size(); v++) {
+			std::string value_string;
+			protozero::pbf_writer value_writer(value_string);
+			mvt_value &pbv = layers[i].values[v];
+
+			if (pbv.type == mvt_string) {
+				value_writer.add_string(1, pbv.string_value);
+			} else if (pbv.type == mvt_float) {
+				value_writer.add_float(2, pbv.numeric_value.float_value);
+			} else if (pbv.type == mvt_double) {
+				value_writer.add_double(3, pbv.numeric_value.double_value);
+			} else if (pbv.type == mvt_int) {
+				value_writer.add_int64(4, pbv.numeric_value.int_value);
+			} else if (pbv.type == mvt_uint) {
+				value_writer.add_uint64(5, pbv.numeric_value.uint_value);
+			} else if (pbv.type == mvt_sint) {
+				value_writer.add_sint64(6, pbv.numeric_value.sint_value);
+			} else if (pbv.type == mvt_bool) {
+				value_writer.add_bool(7, pbv.numeric_value.bool_value);
+			}
+
+			layer_writer.add_message(4, value_string);
+		}
+
+		for (size_t f = 0; f < layers[i].features.size(); f++) {
+			std::string feature_string;
+			protozero::pbf_writer feature_writer(feature_string);
+
+			feature_writer.add_enum(3, layers[i].features[f].type);
+			feature_writer.add_packed_uint32(2, std::begin(layers[i].features[f].tags), std::end(layers[i].features[f].tags));
+
+			if (layers[i].features[f].has_id) {
+				feature_writer.add_uint64(1, layers[i].features[f].id);
+			}
+
+			std::vector<uint32_t> geometry;
+
+			int px = 0, py = 0;
+			int cmd_idx = -1;
+			int cmd = -1;
+			int length = 0;
+
+			std::vector<mvt_geometry> &geom = layers[i].features[f].geometry;
+
+			for (size_t g = 0; g < geom.size(); g++) {
+				int op = geom[g].op;
+
+				if (op != cmd) {
+					if (cmd_idx >= 0) {
+						geometry[cmd_idx] = (length << 3) | (cmd & ((1 << 3) - 1));
+					}
+
+					cmd = op;
+					length = 0;
+					cmd_idx = geometry.size();
+					geometry.push_back(0);
+				}
+
+				if (op == mvt_moveto || op == mvt_lineto) {
+					long long wwx = geom[g].x;
+					long long wwy = geom[g].y;
+
+					int dx = wwx - px;
+					int dy = wwy - py;
+
+					geometry.push_back(protozero::encode_zigzag32(dx));
+					geometry.push_back(protozero::encode_zigzag32(dy));
+
+					px = wwx;
+					py = wwy;
+					length++;
+				} else if (op == mvt_closepath) {
+					length++;
+				} else {
+					fprintf(stderr, "\nInternal error: corrupted geometry\n");
+					exit(EXIT_FAILURE);
+				}
+			}
+
+			if (cmd_idx >= 0) {
+				geometry[cmd_idx] = (length << 3) | (cmd & ((1 << 3) - 1));
+			}
+
+			feature_writer.add_packed_uint32(4, std::begin(geometry), std::end(geometry));
+			layer_writer.add_message(2, feature_string);
+		}
+
+		writer.add_message(3, layer_string);
+	}
+
+	return data;
+}
+
+bool mvt_value::operator<(const mvt_value &o) const {
+	if (type < o.type) {
+		return true;
+	}
+	if (type == o.type) {
+		if ((type == mvt_string && string_value < o.string_value) ||
+		    (type == mvt_float && numeric_value.float_value < o.numeric_value.float_value) ||
+		    (type == mvt_double && numeric_value.double_value < o.numeric_value.double_value) ||
+		    (type == mvt_int && numeric_value.int_value < o.numeric_value.int_value) ||
+		    (type == mvt_uint && numeric_value.uint_value < o.numeric_value.uint_value) ||
+		    (type == mvt_sint && numeric_value.sint_value < o.numeric_value.sint_value) ||
+		    (type == mvt_bool && numeric_value.bool_value < o.numeric_value.bool_value)) {
+			return true;
+		}
+	}
+
+	return false;
+}
+
+static std::string quote(std::string const &s) {
+	std::string buf;
+
+	for (size_t i = 0; i < s.size(); i++) {
+		unsigned char ch = s[i];
+
+		if (ch == '\\' || ch == '\"') {
+			buf.push_back('\\');
+			buf.push_back(ch);
+		} else if (ch < ' ') {
+			char tmp[7];
+			sprintf(tmp, "\\u%04x", ch);
+			buf.append(std::string(tmp));
+		} else {
+			buf.push_back(ch);
+		}
+	}
+
+	return buf;
+}
+
+std::string mvt_value::toString() {
+	if (type == mvt_string) {
+		return quote(string_value);
+	} else if (type == mvt_int) {
+		return std::to_string((long long) numeric_value.int_value);
+	} else if (type == mvt_double) {
+		double v = numeric_value.double_value;
+		if (v == (long long) v) {
+			return std::to_string((long long) v);
+		} else {
+			return milo::dtoa_milo(v);
+		}
+	} else if (type == mvt_float) {
+		double v = numeric_value.float_value;
+		if (v == (long long) v) {
+			return std::to_string((long long) v);
+		} else {
+			return milo::dtoa_milo(v);
+		}
+	} else if (type == mvt_sint) {
+		return std::to_string((long long) numeric_value.sint_value);
+	} else if (type == mvt_uint) {
+		return std::to_string((long long) numeric_value.uint_value);
+	} else if (type == mvt_bool) {
+		return numeric_value.bool_value ? "true" : "false";
+	} else {
+		return "unknown";
+	}
+}
+
+void mvt_layer::tag(mvt_feature &feature, std::string key, mvt_value value) {
+	size_t ko, vo;
+
+	std::map<std::string, size_t>::iterator ki = key_map.find(key);
+	std::map<mvt_value, size_t>::iterator vi = value_map.find(value);
+
+	if (ki == key_map.end()) {
+		ko = keys.size();
+		keys.push_back(key);
+		key_map.insert(std::pair<std::string, size_t>(key, ko));
+	} else {
+		ko = ki->second;
+	}
+
+	if (vi == value_map.end()) {
+		vo = values.size();
+		values.push_back(value);
+		value_map.insert(std::pair<mvt_value, size_t>(value, vo));
+	} else {
+		vo = vi->second;
+	}
+
+	feature.tags.push_back(ko);
+	feature.tags.push_back(vo);
+}
+
+static int is_integer(const char *s, long long *v) {
+	errno = 0;
+	char *endptr;
+
+	*v = strtoll(s, &endptr, 0);
+	if (*v == 0 && errno != 0) {
+		return 0;
+	}
+	if ((*v == LLONG_MIN || *v == LLONG_MAX) && (errno == ERANGE)) {
+		return 0;
+	}
+	if (*endptr != '\0') {
+		// Special case: If it is an integer followed by .0000 or similar,
+		// it is still an integer
+
+		if (*endptr != '.') {
+			return 0;
+		}
+		endptr++;
+		for (; *endptr != '\0'; endptr++) {
+			if (*endptr != '0') {
+				return 0;
+			}
+		}
+
+		return 1;
+	}
+
+	return 1;
+}
+
+mvt_value stringified_to_mvt_value(int type, const char *s) {
+	mvt_value tv;
+
+	if (type == mvt_double) {
+		long long v;
+		if (is_integer(s, &v)) {
+			if (v >= 0) {
+				tv.type = mvt_int;
+				tv.numeric_value.int_value = v;
+			} else {
+				tv.type = mvt_sint;
+				tv.numeric_value.sint_value = v;
+			}
+		} else {
+			double d = atof(s);
+
+			if (d == (float) d) {
+				tv.type = mvt_float;
+				tv.numeric_value.float_value = d;
+			} else {
+				tv.type = mvt_double;
+				tv.numeric_value.double_value = d;
+			}
+		}
+	} else if (type == mvt_bool) {
+		tv.type = mvt_bool;
+		tv.numeric_value.bool_value = (s[0] == 't');
+	} else if (type == mvt_null) {
+		tv.type = mvt_null;
+	} else {
+		tv.type = mvt_string;
+		tv.string_value = s;
+	}
+
+	return tv;
+}

mvt.hpp

@@ -0,0 +1,114 @@
+#ifndef MVT_HPP
+#define MVT_HPP
+
+#include <sqlite3.h>
+#include <string>
+#include <map>
+#include <set>
+#include <vector>
+
+struct mvt_value;
+struct mvt_layer;
+
+enum mvt_operation {
+	mvt_moveto = 1,
+	mvt_lineto = 2,
+	mvt_closepath = 7
+};
+
+struct mvt_geometry {
+	long long x;
+	long long y;
+	int /* mvt_operation */ op;
+
+	mvt_geometry(int op, long long x, long long y);
+
+	bool operator<(mvt_geometry const &s) const {
+		if (y < s.y || (y == s.y && x < s.x)) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	bool operator==(mvt_geometry const &s) const {
+		return y == s.y && x == s.x;
+	}
+};
+
+enum mvt_geometry_type {
+	mvt_point = 1,
+	mvt_linestring = 2,
+	mvt_polygon = 3
+};
+
+struct mvt_feature {
+	std::vector<unsigned> tags;
+	std::vector<mvt_geometry> geometry;
+	int /* mvt_geometry_type */ type;
+	unsigned long long id;
+	bool has_id;
+
+	mvt_feature() {
+		has_id = false;
+		id = 0;
+	}
+};
+
+enum mvt_value_type {
+	mvt_string,
+	mvt_float,
+	mvt_double,
+	mvt_int,
+	mvt_uint,
+	mvt_sint,
+	mvt_bool,
+	mvt_null,
+};
+
+struct mvt_value {
+	mvt_value_type type;
+	std::string string_value;
+	union {
+		float float_value;
+		double double_value;
+		long long int_value;
+		unsigned long long uint_value;
+		long long sint_value;
+		bool bool_value;
+	} numeric_value;
+
+	bool operator<(const mvt_value &o) const;
+	std::string toString();
+};
+
+struct mvt_layer {
+	int version;
+	std::string name;
+	std::vector<mvt_feature> features;
+	std::vector<std::string> keys;
+	std::vector<mvt_value> values;
+	long long extent;
+
+	// Add a key-value pair to a feature, using this layer's constant pool
+	void tag(mvt_feature &feature, std::string key, mvt_value value);
+
+	// For tracking the key-value constants already used in this layer
+	std::map<std::string, size_t> key_map;
+	std::map<mvt_value, size_t> value_map;
+};
+
+struct mvt_tile {
+	std::vector<mvt_layer> layers;
+
+	std::string encode();
+	bool decode(std::string &message, bool &was_compressed);
+};
+
+bool is_compressed(std::string const &data);
+int decompress(std::string const &input, std::string &output);
+int compress(std::string const &input, std::string &output);
+int dezig(unsigned n);
+
+mvt_value stringified_to_mvt_value(int type, const char *s);
+#endif

options.hpp

@@ -0,0 +1,39 @@
+#ifndef OPTIONS_HPP
+#define OPTIONS_HPP
+
+#define A_COALESCE ((int) 'c')
+#define A_REVERSE ((int) 'r')
+#define A_REORDER ((int) 'o')
+#define A_LINE_DROP ((int) 'l')
+#define A_DEBUG_POLYGON ((int) 'D')
+#define A_POLYGON_DROP ((int) 'p')
+#define A_DETECT_SHARED_BORDERS ((int) 'b')
+#define A_PREFER_RADIX_SORT ((int) 'R')
+#define A_CALCULATE_FEATURE_DENSITY ((int) 'g')
+#define A_INCREASE_GAMMA_AS_NEEDED ((int) 'G')
+#define A_MERGE_POLYGONS_AS_NEEDED ((int) 'm')
+#define A_DROP_DENSEST_AS_NEEDED ((int) 's')
+#define A_DROP_FRACTION_AS_NEEDED ((int) 'd')
+#define A_DROP_SMALLEST_AS_NEEDED ((int) 'n')
+#define A_COALESCE_SMALLEST_AS_NEEDED ((int) 'N')
+#define A_GRID_LOW_ZOOMS ((int) 'L')
+#define A_DETECT_WRAPAROUND ((int) 'w')
+#define A_EXTEND_ZOOMS ((int) 'e')
+
+#define P_SIMPLIFY ((int) 's')
+#define P_SIMPLIFY_LOW ((int) 'S')
+#define P_FEATURE_LIMIT ((int) 'f')
+#define P_KILOBYTE_LIMIT ((int) 'k')
+#define P_DYNAMIC_DROP ((int) 'd')
+#define P_INPUT_ORDER ((int) 'i')
+#define P_POLYGON_SPLIT ((int) 'p')
+#define P_CLIPPING ((int) 'c')
+#define P_DUPLICATION ((int) 'D')
+#define P_TINY_POLYGON_REDUCTION ((int) 't')
+#define P_TILE_COMPRESSION ((int) 'C')
+#define P_TILE_STATS ((int) 'g')
+
+extern int prevent[256];
+extern int additional[256];
+
+#endif

plugin.cpp

@@ -0,0 +1,648 @@
+#ifdef __APPLE__
+#define _DARWIN_UNLIMITED_STREAMS
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <vector>
+#include <string>
+#include <map>
+#include <set>
+#include <pthread.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <cmath>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sqlite3.h>
+#include <limits.h>
+#include "main.hpp"
+#include "mvt.hpp"
+#include "mbtiles.hpp"
+#include "projection.hpp"
+#include "geometry.hpp"
+#include "serial.hpp"
+
+extern "C" {
+#include "jsonpull/jsonpull.h"
+}
+
+#include "plugin.hpp"
+#include "write_json.hpp"
+#include "read_json.hpp"
+
+struct writer_arg {
+	int write_to;
+	std::vector<mvt_layer> *layers;
+	unsigned z;
+	unsigned x;
+	unsigned y;
+	int extent;
+};
+
+void *run_writer(void *a) {
+	writer_arg *wa = (writer_arg *) a;
+
+	FILE *fp = fdopen(wa->write_to, "w");
+	if (fp == NULL) {
+		perror("fdopen (pipe writer)");
+		exit(EXIT_FAILURE);
+	}
+
+	for (size_t i = 0; i < wa->layers->size(); i++) {
+		layer_to_geojson(fp, (*(wa->layers))[i], wa->z, wa->x, wa->y, false, true, false, 0, 0, 0, true);
+	}
+
+	if (fclose(fp) != 0) {
+		if (errno == EPIPE) {
+			static bool warned = false;
+			if (!warned) {
+				fprintf(stderr, "Warning: broken pipe in postfilter\n");
+				warned = true;
+			}
+		} else {
+			perror("fclose output to filter");
+			exit(EXIT_FAILURE);
+		}
+	}
+
+	return NULL;
+}
+
+// XXX deduplicate
+static std::vector<mvt_geometry> to_feature(drawvec &geom) {
+	std::vector<mvt_geometry> out;
+
+	for (size_t i = 0; i < geom.size(); i++) {
+		out.push_back(mvt_geometry(geom[i].op, geom[i].x, geom[i].y));
+	}
+
+	return out;
+}
+
+// Reads from the postfilter
+std::vector<mvt_layer> parse_layers(int fd, int z, unsigned x, unsigned y, std::vector<std::map<std::string, layermap_entry>> *layermaps, size_t tiling_seg, std::vector<std::vector<std::string>> *layer_unmaps, int extent) {
+	std::map<std::string, mvt_layer> ret;
+
+	FILE *f = fdopen(fd, "r");
+	if (f == NULL) {
+		perror("fdopen filter output");
+		exit(EXIT_FAILURE);
+	}
+	json_pull *jp = json_begin_file(f);
+
+	while (1) {
+		json_object *j = json_read(jp);
+		if (j == NULL) {
+			if (jp->error != NULL) {
+				fprintf(stderr, "Filter output:%d: %s\n", jp->line, jp->error);
+				if (jp->root != NULL) {
+					json_context(jp->root);
+				}
+				exit(EXIT_FAILURE);
+			}
+
+			json_free(jp->root);
+			break;
+		}
+
+		json_object *type = json_hash_get(j, "type");
+		if (type == NULL || type->type != JSON_STRING) {
+			continue;
+		}
+		if (strcmp(type->string, "Feature") != 0) {
+			continue;
+		}
+
+		json_object *geometry = json_hash_get(j, "geometry");
+		if (geometry == NULL) {
+			fprintf(stderr, "Filter output:%d: filtered feature with no geometry\n", jp->line);
+			json_context(j);
+			json_free(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *properties = json_hash_get(j, "properties");
+		if (properties == NULL || (properties->type != JSON_HASH && properties->type != JSON_NULL)) {
+			fprintf(stderr, "Filter output:%d: feature without properties hash\n", jp->line);
+			json_context(j);
+			json_free(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *geometry_type = json_hash_get(geometry, "type");
+		if (geometry_type == NULL) {
+			fprintf(stderr, "Filter output:%d: null geometry (additional not reported)\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		if (geometry_type->type != JSON_STRING) {
+			fprintf(stderr, "Filter output:%d: geometry type is not a string\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *coordinates = json_hash_get(geometry, "coordinates");
+		if (coordinates == NULL || coordinates->type != JSON_ARRAY) {
+			fprintf(stderr, "Filter output:%d: feature without coordinates array\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		int t;
+		for (t = 0; t < GEOM_TYPES; t++) {
+			if (strcmp(geometry_type->string, geometry_names[t]) == 0) {
+				break;
+			}
+		}
+		if (t >= GEOM_TYPES) {
+			fprintf(stderr, "Filter output:%d: Can't handle geometry type %s\n", jp->line, geometry_type->string);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		std::string layername = "unknown";
+		json_object *tippecanoe = json_hash_get(j, "tippecanoe");
+		json_object *layer = NULL;
+		if (tippecanoe != NULL) {
+			layer = json_hash_get(tippecanoe, "layer");
+			if (layer != NULL && layer->type == JSON_STRING) {
+				layername = std::string(layer->string);
+			}
+		}
+
+		if (ret.count(layername) == 0) {
+			mvt_layer l;
+			l.name = layername;
+			l.version = 2;
+			l.extent = extent;
+
+			ret.insert(std::pair<std::string, mvt_layer>(layername, l));
+		}
+		auto l = ret.find(layername);
+
+		drawvec dv;
+		parse_geometry(t, coordinates, dv, VT_MOVETO, "Filter output", jp->line, j);
+		if (mb_geometry[t] == VT_POLYGON) {
+			dv = fix_polygon(dv);
+		}
+
+		// Scale and offset geometry from global to tile
+		for (size_t i = 0; i < dv.size(); i++) {
+			long long scale = 1LL << (32 - z);
+			dv[i].x = std::round((dv[i].x - scale * x) * extent / (double) scale);
+			dv[i].y = std::round((dv[i].y - scale * y) * extent / (double) scale);
+		}
+
+		if (mb_geometry[t] == VT_POLYGON) {
+			dv = clean_or_clip_poly(dv, 0, 0, 0, false);
+			if (dv.size() < 3) {
+				dv.clear();
+			}
+		}
+		dv = remove_noop(dv, mb_geometry[t], 0);
+		if (mb_geometry[t] == VT_POLYGON) {
+			dv = close_poly(dv);
+		}
+
+		if (dv.size() > 0) {
+			mvt_feature feature;
+			feature.type = mb_geometry[t];
+			feature.geometry = to_feature(dv);
+
+			json_object *id = json_hash_get(j, "id");
+			if (id != NULL) {
+				feature.id = atoll(id->string);
+				feature.has_id = true;
+			}
+
+			std::map<std::string, layermap_entry> &layermap = (*layermaps)[tiling_seg];
+			if (layermap.count(layername) == 0) {
+				layermap_entry lme = layermap_entry(layermap.size());
+				lme.minzoom = z;
+				lme.maxzoom = z;
+
+				layermap.insert(std::pair<std::string, layermap_entry>(layername, lme));
+
+				if (lme.id >= (*layer_unmaps)[tiling_seg].size()) {
+					(*layer_unmaps)[tiling_seg].resize(lme.id + 1);
+					(*layer_unmaps)[tiling_seg][lme.id] = layername;
+				}
+			}
+
+			auto fk = layermap.find(layername);
+			if (fk == layermap.end()) {
+				fprintf(stderr, "Internal error: layer %s not found\n", layername.c_str());
+				exit(EXIT_FAILURE);
+			}
+			if (z < fk->second.minzoom) {
+				fk->second.minzoom = z;
+			}
+			if (z > fk->second.maxzoom) {
+				fk->second.maxzoom = z;
+			}
+
+			if (feature.type == mvt_point) {
+				fk->second.points++;
+			} else if (feature.type == mvt_linestring) {
+				fk->second.lines++;
+			} else if (feature.type == mvt_polygon) {
+				fk->second.polygons++;
+			}
+
+			for (size_t i = 0; i < properties->length; i++) {
+				int tp = -1;
+				std::string s;
+
+				stringify_value(properties->values[i], tp, s, "Filter output", jp->line, j, "");
+				if (tp >= 0) {
+					mvt_value v = stringified_to_mvt_value(tp, s.c_str());
+					l->second.tag(feature, std::string(properties->keys[i]->string), v);
+
+					type_and_string attrib;
+					attrib.type = tp;
+					attrib.string = s;
+
+					add_to_file_keys(fk->second.file_keys, std::string(properties->keys[i]->string), attrib);
+				}
+			}
+
+			l->second.features.push_back(feature);
+		}
+
+		json_free(j);
+	}
+
+	json_end(jp);
+	if (fclose(f) != 0) {
+		perror("fclose postfilter output");
+		exit(EXIT_FAILURE);
+	}
+
+	std::vector<mvt_layer> final;
+	for (auto a : ret) {
+		final.push_back(a.second);
+	}
+	return final;
+}
+
+// Reads from the prefilter
+serial_feature parse_feature(json_pull *jp, int z, unsigned x, unsigned y, std::vector<std::map<std::string, layermap_entry>> *layermaps, size_t tiling_seg, std::vector<std::vector<std::string>> *layer_unmaps, bool postfilter) {
+	serial_feature sf;
+
+	while (1) {
+		json_object *j = json_read(jp);
+		if (j == NULL) {
+			if (jp->error != NULL) {
+				fprintf(stderr, "Filter output:%d: %s\n", jp->line, jp->error);
+				if (jp->root != NULL) {
+					json_context(jp->root);
+				}
+				exit(EXIT_FAILURE);
+			}
+
+			json_free(jp->root);
+			sf.t = -1;
+			return sf;
+		}
+
+		json_object *type = json_hash_get(j, "type");
+		if (type == NULL || type->type != JSON_STRING) {
+			continue;
+		}
+		if (strcmp(type->string, "Feature") != 0) {
+			continue;
+		}
+
+		json_object *geometry = json_hash_get(j, "geometry");
+		if (geometry == NULL) {
+			fprintf(stderr, "Filter output:%d: filtered feature with no geometry\n", jp->line);
+			json_context(j);
+			json_free(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *properties = json_hash_get(j, "properties");
+		if (properties == NULL || (properties->type != JSON_HASH && properties->type != JSON_NULL)) {
+			fprintf(stderr, "Filter output:%d: feature without properties hash\n", jp->line);
+			json_context(j);
+			json_free(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *geometry_type = json_hash_get(geometry, "type");
+		if (geometry_type == NULL) {
+			fprintf(stderr, "Filter output:%d: null geometry (additional not reported)\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		if (geometry_type->type != JSON_STRING) {
+			fprintf(stderr, "Filter output:%d: geometry type is not a string\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		json_object *coordinates = json_hash_get(geometry, "coordinates");
+		if (coordinates == NULL || coordinates->type != JSON_ARRAY) {
+			fprintf(stderr, "Filter output:%d: feature without coordinates array\n", jp->line);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		int t;
+		for (t = 0; t < GEOM_TYPES; t++) {
+			if (strcmp(geometry_type->string, geometry_names[t]) == 0) {
+				break;
+			}
+		}
+		if (t >= GEOM_TYPES) {
+			fprintf(stderr, "Filter output:%d: Can't handle geometry type %s\n", jp->line, geometry_type->string);
+			json_context(j);
+			exit(EXIT_FAILURE);
+		}
+
+		drawvec dv;
+		parse_geometry(t, coordinates, dv, VT_MOVETO, "Filter output", jp->line, j);
+		if (mb_geometry[t] == VT_POLYGON) {
+			dv = fix_polygon(dv);
+		}
+
+		// Scale and offset geometry from global to tile
+		double scale = 1LL << geometry_scale;
+		for (size_t i = 0; i < dv.size(); i++) {
+			unsigned sx = 0, sy = 0;
+			if (z != 0) {
+				sx = x << (32 - z);
+				sy = y << (32 - z);
+			}
+			dv[i].x = std::round(dv[i].x / scale) * scale - sx;
+			dv[i].y = std::round(dv[i].y / scale) * scale - sy;
+		}
+
+		if (dv.size() > 0) {
+			sf.t = mb_geometry[t];
+			sf.segment = tiling_seg;
+			sf.geometry = dv;
+			sf.seq = 0;
+			sf.index = 0;
+			sf.bbox[0] = sf.bbox[1] = LLONG_MAX;
+			sf.bbox[2] = sf.bbox[3] = LLONG_MIN;
+			sf.extent = 0;
+			sf.m = 0;
+			sf.metapos = 0;
+			sf.has_id = false;
+
+			std::string layername = "unknown";
+			json_object *tippecanoe = json_hash_get(j, "tippecanoe");
+			if (tippecanoe != NULL) {
+				json_object *layer = json_hash_get(tippecanoe, "layer");
+				if (layer != NULL && layer->type == JSON_STRING) {
+					layername = std::string(layer->string);
+				}
+
+				json_object *index = json_hash_get(tippecanoe, "index");
+				if (index != NULL && index->type == JSON_NUMBER) {
+					sf.index = index->number;
+				}
+
+				json_object *sequence = json_hash_get(tippecanoe, "sequence");
+				if (sequence != NULL && sequence->type == JSON_NUMBER) {
+					sf.seq = sequence->number;
+				}
+
+				json_object *extent = json_hash_get(tippecanoe, "extent");
+				if (extent != NULL && sequence->type == JSON_NUMBER) {
+					sf.extent = extent->number;
+				}
+			}
+
+			for (size_t i = 0; i < dv.size(); i++) {
+				if (dv[i].op == VT_MOVETO || dv[i].op == VT_LINETO) {
+					if (dv[i].x < sf.bbox[0]) {
+						sf.bbox[0] = dv[i].x;
+					}
+					if (dv[i].y < sf.bbox[1]) {
+						sf.bbox[1] = dv[i].y;
+					}
+					if (dv[i].x > sf.bbox[2]) {
+						sf.bbox[2] = dv[i].x;
+					}
+					if (dv[i].y > sf.bbox[3]) {
+						sf.bbox[3] = dv[i].y;
+					}
+				}
+			}
+
+			json_object *id = json_hash_get(j, "id");
+			if (id != NULL) {
+				sf.id = atoll(id->string);
+				sf.has_id = true;
+			}
+
+			std::map<std::string, layermap_entry> &layermap = (*layermaps)[tiling_seg];
+
+			if (layermap.count(layername) == 0) {
+				layermap_entry lme = layermap_entry(layermap.size());
+				lme.minzoom = z;
+				lme.maxzoom = z;
+
+				layermap.insert(std::pair<std::string, layermap_entry>(layername, lme));
+
+				if (lme.id >= (*layer_unmaps)[tiling_seg].size()) {
+					(*layer_unmaps)[tiling_seg].resize(lme.id + 1);
+					(*layer_unmaps)[tiling_seg][lme.id] = layername;
+				}
+			}
+
+			auto fk = layermap.find(layername);
+			if (fk == layermap.end()) {
+				fprintf(stderr, "Internal error: layer %s not found\n", layername.c_str());
+				exit(EXIT_FAILURE);
+			}
+			sf.layer = fk->second.id;
+
+			if (z < fk->second.minzoom) {
+				fk->second.minzoom = z;
+			}
+			if (z > fk->second.maxzoom) {
+				fk->second.maxzoom = z;
+			}
+
+			if (!postfilter) {
+				if (sf.t == mvt_point) {
+					fk->second.points++;
+				} else if (sf.t == mvt_linestring) {
+					fk->second.lines++;
+				} else if (sf.t == mvt_polygon) {
+					fk->second.polygons++;
+				}
+			}
+
+			for (size_t i = 0; i < properties->length; i++) {
+				serial_val v;
+				v.type = -1;
+
+				stringify_value(properties->values[i], v.type, v.s, "Filter output", jp->line, j, "");
+
+				if (v.type >= 0) {
+					sf.full_keys.push_back(std::string(properties->keys[i]->string));
+					sf.full_values.push_back(v);
+
+					type_and_string attrib;
+					attrib.string = v.s;
+					attrib.type = v.type;
+
+					if (!postfilter) {
+						add_to_file_keys(fk->second.file_keys, std::string(properties->keys[i]->string), attrib);
+					}
+				}
+			}
+
+			json_free(j);
+			return sf;
+		}
+
+		json_free(j);
+	}
+}
+
+static pthread_mutex_t pipe_lock = PTHREAD_MUTEX_INITIALIZER;
+
+void setup_filter(const char *filter, int *write_to, int *read_from, pid_t *pid, unsigned z, unsigned x, unsigned y) {
+	// This will create two pipes, a new thread, and a new process.
+	//
+	// The new process will read from one pipe and write to the other, and execute the filter.
+	// The new thread will write the GeoJSON to the pipe that leads to the filter.
+	// The original thread will read the GeoJSON from the filter and convert it back into vector tiles.
+
+	if (pthread_mutex_lock(&pipe_lock) != 0) {
+		perror("pthread_mutex_lock (pipe)");
+		exit(EXIT_FAILURE);
+	}
+
+	int pipe_orig[2], pipe_filtered[2];
+	if (pipe(pipe_orig) < 0) {
+		perror("pipe (original features)");
+		exit(EXIT_FAILURE);
+	}
+	if (pipe(pipe_filtered) < 0) {
+		perror("pipe (filtered features)");
+		exit(EXIT_FAILURE);
+	}
+
+	std::string z_str = std::to_string(z);
+	std::string x_str = std::to_string(x);
+	std::string y_str = std::to_string(y);
+
+	*pid = fork();
+	if (*pid < 0) {
+		perror("fork");
+		exit(EXIT_FAILURE);
+	} else if (*pid == 0) {
+		// child
+
+		if (dup2(pipe_orig[0], 0) < 0) {
+			perror("dup child stdin");
+			exit(EXIT_FAILURE);
+		}
+		if (dup2(pipe_filtered[1], 1) < 0) {
+			perror("dup child stdout");
+			exit(EXIT_FAILURE);
+		}
+		if (close(pipe_orig[1]) != 0) {
+			perror("close output to filter");
+			exit(EXIT_FAILURE);
+		}
+		if (close(pipe_filtered[0]) != 0) {
+			perror("close input from filter");
+			exit(EXIT_FAILURE);
+		}
+		if (close(pipe_orig[0]) != 0) {
+			perror("close dup input of filter");
+			exit(EXIT_FAILURE);
+		}
+		if (close(pipe_filtered[1]) != 0) {
+			perror("close dup output of filter");
+			exit(EXIT_FAILURE);
+		}
+
+		// XXX close other fds?
+
+		if (execlp("sh", "sh", "-c", filter, "sh", z_str.c_str(), x_str.c_str(), y_str.c_str(), NULL) != 0) {
+			perror("exec");
+			exit(EXIT_FAILURE);
+		}
+	} else {
+		// parent
+
+		if (close(pipe_orig[0]) != 0) {
+			perror("close filter-side reader");
+			exit(EXIT_FAILURE);
+		}
+		if (close(pipe_filtered[1]) != 0) {
+			perror("close filter-side writer");
+			exit(EXIT_FAILURE);
+		}
+		if (fcntl(pipe_orig[1], F_SETFD, FD_CLOEXEC) != 0) {
+			perror("cloxec output to filter");
+			exit(EXIT_FAILURE);
+		}
+		if (fcntl(pipe_filtered[0], F_SETFD, FD_CLOEXEC) != 0) {
+			perror("cloxec input from filter");
+			exit(EXIT_FAILURE);
+		}
+
+		if (pthread_mutex_unlock(&pipe_lock) != 0) {
+			perror("pthread_mutex_unlock (pipe_lock)");
+			exit(EXIT_FAILURE);
+		}
+
+		*write_to = pipe_orig[1];
+		*read_from = pipe_filtered[0];
+	}
+}
+
+std::vector<mvt_layer> filter_layers(const char *filter, std::vector<mvt_layer> &layers, unsigned z, unsigned x, unsigned y, std::vector<std::map<std::string, layermap_entry>> *layermaps, size_t tiling_seg, std::vector<std::vector<std::string>> *layer_unmaps, int extent) {
+	int write_to, read_from;
+	pid_t pid;
+	setup_filter(filter, &write_to, &read_from, &pid, z, x, y);
+
+	writer_arg wa;
+	wa.write_to = write_to;
+	wa.layers = &layers;
+	wa.z = z;
+	wa.x = x;
+	wa.y = y;
+	wa.extent = extent;
+
+	pthread_t writer;
+	if (pthread_create(&writer, NULL, run_writer, &wa) != 0) {
+		perror("pthread_create (filter writer)");
+		exit(EXIT_FAILURE);
+	}
+
+	std::vector<mvt_layer> nlayers = parse_layers(read_from, z, x, y, layermaps, tiling_seg, layer_unmaps, extent);
+
+	while (1) {
+		int stat_loc;
+		if (waitpid(pid, &stat_loc, 0) < 0) {
+			perror("waitpid for filter\n");
+			exit(EXIT_FAILURE);
+		}
+		if (WIFEXITED(stat_loc) || WIFSIGNALED(stat_loc)) {
+			break;
+		}
+	}
+
+	void *ret;
+	if (pthread_join(writer, &ret) != 0) {
+		perror("pthread_join filter writer");
+		exit(EXIT_FAILURE);
+	}
+
+	return nlayers;
+}

plugin.hpp

@@ -0,0 +1,3 @@
+std::vector<mvt_layer> filter_layers(const char *filter, std::vector<mvt_layer> &layer, unsigned z, unsigned x, unsigned y, std::vector<std::map<std::string, layermap_entry>> *layermaps, size_t tiling_seg, std::vector<std::vector<std::string>> *layer_unmaps, int extent);
+void setup_filter(const char *filter, int *write_to, int *read_from, pid_t *pid, unsigned z, unsigned x, unsigned y);
+serial_feature parse_feature(json_pull *jp, int z, unsigned x, unsigned y, std::vector<std::map<std::string, layermap_entry>> *layermaps, size_t tiling_seg, std::vector<std::vector<std::string>> *layer_unmaps, bool filters);

pool.c

@@ -1,119 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include "pool.h"
-
-#define POOL_WIDTH 256
-
-static int hash(const char *s) {
-	int h = 0;
-	for (; *s; s++) {
-		h = h * 37 + *s;
-	}
-	h = h & 0xFF;
-	return h;
-}
-
-struct pool_val *pool(struct pool *p, const char *s, int type) {
-	int h = hash(s);
-	struct pool_val **v = &(p->vals[h]);
-
-	while (*v != NULL) {
-		int cmp = strcmp(s, (*v)->s);
-
-		if (cmp == 0) {
-			cmp = type - (*v)->type;
-		}
-
-		if (cmp == 0) {
-			return *v;
-		} else if (cmp < 0) {
-			v = &((*v)->left);
-		} else {
-			v = &((*v)->right);
-		}
-	}
-
-	struct pool_val *nv = malloc(sizeof(struct pool_val));
-	if (nv == NULL) {
-		fprintf(stderr, "out of memory making string pool\n");
-		exit(EXIT_FAILURE);
-	}
-	nv->left = NULL;
-	nv->right = NULL;
-	nv->next = NULL;
-	nv->s = s;
-	nv->type = type;
-	nv->n = p->n++;
-
-	if (p->tail != NULL) {
-		p->tail->next = nv;
-	}
-	p->tail = nv;
-	if (p->head == NULL) {
-		p->head = nv;
-	}
-
-	*v = nv;
-	return *v;
-}
-
-int is_pooled(struct pool *p, const char *s, int type) {
-	int h = hash(s);
-	struct pool_val **v = &(p->vals[h]);
-
-	while (*v != NULL) {
-		int cmp = strcmp(s, (*v)->s);
-
-		if (cmp == 0) {
-			cmp = type - (*v)->type;
-		}
-
-		if (cmp == 0) {
-			return 1;
-		} else if (cmp < 0) {
-			v = &((*v)->left);
-		} else {
-			v = &((*v)->right);
-		}
-	}
-
-	return 0;
-}
-
-void pool_free1(struct pool *p, void (*func)(void *)) {
-	while (p->head != NULL) {
-		if (func != NULL) {
-			func((void *) p->head->s);
-		}
-
-		struct pool_val *next = p->head->next;
-		free(p->head);
-		p->head = next;
-	}
-
-	p->head = NULL;
-	p->tail = NULL;
-
-	free(p->vals);
-	p->vals = NULL;
-}
-
-void pool_free(struct pool *p) {
-	pool_free1(p, NULL);
-}
-
-void pool_free_strings(struct pool *p) {
-	pool_free1(p, free);
-}
-
-void pool_init(struct pool *p, int n) {
-	p->n = n;
-	p->vals = calloc(POOL_WIDTH, sizeof(struct pool_val *));
-	if (p->vals == NULL) {
-		fprintf(stderr, "out of memory creating string pool\n");
-		exit(EXIT_FAILURE);
-	}
-	p->head = NULL;
-	p->tail = NULL;
-}

pool.cpp

@@ -0,0 +1,121 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <math.h>
+#include "memfile.hpp"
+#include "pool.hpp"
+
+int swizzlecmp(const char *a, const char *b) {
+	ssize_t alen = strlen(a);
+	ssize_t blen = strlen(b);
+
+	if (strcmp(a, b) == 0) {
+		return 0;
+	}
+
+	long long hash1 = 0, hash2 = 0;
+	for (ssize_t i = alen - 1; i >= 0; i--) {
+		hash1 = (hash1 * 37 + a[i]) & INT_MAX;
+	}
+	for (ssize_t i = blen - 1; i >= 0; i--) {
+		hash2 = (hash2 * 37 + b[i]) & INT_MAX;
+	}
+
+	int h1 = hash1, h2 = hash2;
+	if (h1 == h2) {
+		return strcmp(a, b);
+	}
+
+	return h1 - h2;
+}
+
+long long addpool(struct memfile *poolfile, struct memfile *treefile, const char *s, char type) {
+	unsigned long *sp = &treefile->tree;
+	size_t depth = 0;
+
+	// In typical data, traversal depth generally stays under 2.5x
+	size_t max = 3 * log(treefile->off / sizeof(struct stringpool)) / log(2);
+	if (max < 30) {
+		max = 30;
+	}
+
+	while (*sp != 0) {
+		int cmp = swizzlecmp(s, poolfile->map + ((struct stringpool *) (treefile->map + *sp))->off + 1);
+
+		if (cmp == 0) {
+			cmp = type - (poolfile->map + ((struct stringpool *) (treefile->map + *sp))->off)[0];
+		}
+
+		if (cmp < 0) {
+			sp = &(((struct stringpool *) (treefile->map + *sp))->left);
+		} else if (cmp > 0) {
+			sp = &(((struct stringpool *) (treefile->map + *sp))->right);
+		} else {
+			return ((struct stringpool *) (treefile->map + *sp))->off;
+		}
+
+		depth++;
+		if (depth > max) {
+			// Search is very deep, so string is probably unique.
+			// Add it to the pool without adding it to the search tree.
+
+			long long off = poolfile->off;
+			if (memfile_write(poolfile, &type, 1) < 0) {
+				perror("memfile write");
+				exit(EXIT_FAILURE);
+			}
+			if (memfile_write(poolfile, (void *) s, strlen(s) + 1) < 0) {
+				perror("memfile write");
+				exit(EXIT_FAILURE);
+			}
+			return off;
+		}
+	}
+
+	// *sp is probably in the memory-mapped file, and will move if the file grows.
+	long long ssp;
+	if (sp == &treefile->tree) {
+		ssp = -1;
+	} else {
+		ssp = ((char *) sp) - treefile->map;
+	}
+
+	long long off = poolfile->off;
+	if (memfile_write(poolfile, &type, 1) < 0) {
+		perror("memfile write");
+		exit(EXIT_FAILURE);
+	}
+	if (memfile_write(poolfile, (void *) s, strlen(s) + 1) < 0) {
+		perror("memfile write");
+		exit(EXIT_FAILURE);
+	}
+
+	if (off >= LONG_MAX || treefile->off >= LONG_MAX) {
+		// Tree or pool is bigger than 2GB
+		static bool warned = false;
+		if (!warned) {
+			fprintf(stderr, "Warning: string pool is very large.\n");
+			warned = true;
+		}
+		return off;
+	}
+
+	struct stringpool tsp;
+	tsp.left = 0;
+	tsp.right = 0;
+	tsp.off = off;
+
+	long long p = treefile->off;
+	if (memfile_write(treefile, &tsp, sizeof(struct stringpool)) < 0) {
+		perror("memfile write");
+		exit(EXIT_FAILURE);
+	}
+
+	if (ssp == -1) {
+		treefile->tree = p;
+	} else {
+		*((long long *) (treefile->map + ssp)) = p;
+	}
+	return off;
+}

pool.h

@@ -1,24 +0,0 @@
-struct pool_val {
-	const char *s;
-	int type;
-	int n;
-
-	struct pool_val *left;
-	struct pool_val *right;
-
-	struct pool_val *next;
-};
-
-struct pool {
-	struct pool_val **vals;
-
-	struct pool_val *head;
-	struct pool_val *tail;
-	int n;
-};
-
-struct pool_val *pool(struct pool *p, const char *s, int type);
-void pool_free(struct pool *p);
-void pool_free_strings(struct pool *p);
-void pool_init(struct pool *p, int n);
-int is_pooled(struct pool *p, const char *s, int type);