From 7f24cd6767be123593c44bd7dff08331bc39907e Mon Sep 17 00:00:00 2001
From: Eric Fischer <enf@pobox.com>
Date: Mon, 2 Nov 2015 14:03:45 -0800
Subject: [PATCH] Don't produce layers with no features. Say "layer" instead of
 "name" in decode.

---
 decode.cc | 2 +-
 tile.cc   | 4 ++++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/decode.cc b/decode.cc
index 693abc9..16738c0 100644
--- a/decode.cc
+++ b/decode.cc
@@ -115,7 +115,7 @@ void handle(std::string message, int z, unsigned x, unsigned y, int describe) {
 			}
 
 			printf("{ \"type\": \"FeatureCollection\"");
-			printf(", \"properties\": { \"name\": ");
+			printf(", \"properties\": { \"layer\": ");
 			printq(layer.name().c_str());
 			printf(" }");
 			printf(", \"features\": [\n");
diff --git a/tile.cc b/tile.cc
index d956a0a..ee1c928 100644
--- a/tile.cc
+++ b/tile.cc
@@ -246,6 +246,10 @@ mapnik::vector::tile create_tile(char **layernames, int line_detail, std::vector
 
 	int i;
 	for (i = 0; i < nlayers; i++) {
+		if (features[i].size() == 0) {
+			continue;
+		}
+
 		mapnik::vector::tile_layer *layer = tile.add_layers();
 
 		layer->set_name(layernames[i]);