1 files changed, 24 insertions, 0 deletions
diff --git a/src/mbgl/style/expression/expression.cpp b/src/mbgl/style/expression/expression.cpp
index 3252bb632f..66e2e30b14 100644
--- a/src/mbgl/style/expression/expression.cpp
+++ b/src/mbgl/style/expression/expression.cpp
@@ -9,8 +9,16 @@ namespace expression {
 class GeoJSONFeature : public GeometryTileFeature {
 public:
     const Feature& feature;
+    mutable optional<GeometryCollection> geometry;
 
     GeoJSONFeature(const Feature& feature_) : feature(feature_) {}
+    GeoJSONFeature(const Feature& feature_, const CanonicalTileID& canonical) : feature(feature_) {
+        geometry = convertGeometry(feature.geometry, canonical);
+        // https://github.com/mapbox/geojson-vt-cpp/issues/44
+        if (getType() == FeatureType::Polygon) {
+            geometry = fixupPolygons(*geometry);
+        }
+    }
 
     FeatureType getType() const override  {
         return apply_visitor(ToFeatureType(), feature.geometry);
@@ -24,6 +32,11 @@ public:
         }
         return optional<mbgl::Value>();
     }
+    const GeometryCollection& getGeometries() const override {
+        if (geometry) return *geometry;
+        geometry = GeometryCollection();
+        return *geometry;
+    }
 };
 
 EvaluationResult Expression::evaluate(optional<float> zoom,
@@ -41,6 +54,17 @@ EvaluationResult Expression::evaluate(optional<float> zoom,
     return this->evaluate(EvaluationContext(zoom, &f, colorRampParameter).withAvailableImages(&availableImages));
 }
 
+EvaluationResult Expression::evaluate(optional<float> zoom,
+                                      const Feature& feature,
+                                      optional<double> colorRampParameter,
+                                      const std::set<std::string>& availableImages,
+                                      const CanonicalTileID& canonical) const {
+    GeoJSONFeature f(feature, canonical);
+    return this->evaluate(EvaluationContext(zoom, &f, colorRampParameter)
+                              .withAvailableImages(&availableImages)
+                              .withCanonicalTileID(&canonical));
+}
+
 EvaluationResult Expression::evaluate(optional<mbgl::Value> accumulated, const Feature& feature) const {
     GeoJSONFeature f(feature);
     return this->evaluate(EvaluationContext(accumulated, &f));