[core] Polylabel-based "pole of inaccessibility" symbol placement

mapbox · Dec 16, 2016 · bc6e768 · bc6e768
1 parent da7486b
commit bc6e768
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Showing 4 changed files with 18 additions and 6 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -52,6 +52,7 @@ mason_use(earcut VERSION 0.12.1 HEADER_ONLY)
 mason_use(protozero VERSION 1.4.2 HEADER_ONLY)
 mason_use(pixelmatch VERSION 0.10.0 HEADER_ONLY)
 mason_use(geojson VERSION 0.4.0 HEADER_ONLY)
+mason_use(polylabel VERSION 1.0.2 HEADER_ONLY)
 
 if(WITH_COVERAGE)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --coverage")

diff --git a/cmake/core.cmake b/cmake/core.cmake
@@ -45,6 +45,7 @@ target_add_mason_package(mbgl-core PRIVATE supercluster)
 target_add_mason_package(mbgl-core PRIVATE kdbush)
 target_add_mason_package(mbgl-core PRIVATE earcut)
 target_add_mason_package(mbgl-core PRIVATE protozero)
+target_add_mason_package(mbgl-core PRIVATE polylabel)
 
 mbgl_platform_core()
 

diff --git a/package.json b/package.json
@@ -24,7 +24,7 @@
     "lodash": "^4.16.4",
     "mapbox-gl": "mapbox/mapbox-gl-js#ab836206d415ca3a74257a3066d11a54ab2838cb",
     "mapbox-gl-style-spec": "mapbox/mapbox-gl-style-spec#49e8b407bdbbe6f7c92dbcb56d3d51f425fc2653",
-    "mapbox-gl-test-suite": "mapbox/mapbox-gl-test-suite#e1ada02a706fd124fc3441fd3a2b3cda67960ff5",
+    "mapbox-gl-test-suite": "mapbox/mapbox-gl-test-suite#d30b002b39507925d4f0ee9e20f58685b3b5af30",
     "mkdirp": "^0.5.1",
     "node-cmake": "^1.2.1",
     "pixelmatch": "^4.0.2",

diff --git a/src/mbgl/layout/symbol_layout.cpp b/src/mbgl/layout/symbol_layout.cpp
@@ -20,6 +20,8 @@
 #include <mbgl/util/platform.hpp>
 #include <mbgl/util/logging.hpp>
 
+#include <mapbox/polylabel.hpp>
+
 namespace mbgl {
 
 using namespace style;
@@ -301,12 +303,20 @@ void SymbolLayout::addFeature(const SymbolFeature& feature,
             }
         }
     } else if (feature.type == FeatureType::Polygon) {
-        // TODO: pole of inaccessibility
-        for (const auto& ring : feature.geometry) {
-            for (const auto& point : ring) {
-                Anchor anchor(point.x, point.y, 0, minScale);
-                addSymbolInstance(ring, anchor);
+        for (const auto& polygon : classifyRings(feature.geometry)) {
+            Polygon<double> poly;
+            for (const auto& ring : polygon) {
+                LinearRing<double> r;
+                for (const auto& p : ring) {
+                    r.push_back(convertPoint<double>(p));
+                }
+                poly.push_back(r);
             }
+
+            // 16 here represents 2 pixels
+            auto poi = mapbox::polylabel(poly, 16.0);
+            Anchor anchor(poi.x, poi.y, 0, minScale);
+            addSymbolInstance(polygon[0], anchor);
         }
     } else if (feature.type == FeatureType::LineString) {
         for (const auto& line : feature.geometry) {