From acb97361a00b746a12d76a165480c4d6453835f2 Mon Sep 17 00:00:00 2001
From: Eric Fischer <enf@pobox.com>
Date: Thu, 7 Apr 2016 16:45:45 -0700
Subject: [PATCH] Fix a line simplification crash when a segment degenerates to
 a single point

---
 CHANGELOG.md | 4 ++++
 geometry.cc  | 4 +++-
 version.h    | 2 +-
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e7846f1..362c2c9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 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
diff --git a/geometry.cc b/geometry.cc
index 008bf6b..27913be 100644
--- a/geometry.cc
+++ b/geometry.cc
@@ -831,7 +831,9 @@ drawvec simplify_lines(drawvec &geom, int z, int detail) {
 			geom[i].necessary = 1;
 			geom[j - 1].necessary = 1;
 
-			douglas_peucker(geom, i, j - i, res);
+			if (j - i > 1) {
+				douglas_peucker(geom, i, j - i, res);
+			}
 			i = j - 1;
 		}
 	}
diff --git a/version.h b/version.h
index a012608..0db3fcd 100644
--- a/version.h
+++ b/version.h
@@ -1 +1 @@
-#define VERSION "tippecanoe v1.9.10\n"
+#define VERSION "tippecanoe v1.9.11\n"