1 files changed, 5 insertions, 0 deletions
diff --git a/src/mbgl/layout/symbol_feature.hpp b/src/mbgl/layout/symbol_feature.hpp
index e16dd0b2f3..72f613d4b6 100644
--- a/src/mbgl/layout/symbol_feature.hpp
+++ b/src/mbgl/layout/symbol_feature.hpp
@@ -22,10 +22,15 @@ public:
     FeatureIdentifier getID() const override { return feature->getID(); };
     GeometryCollection getGeometries() const override { return geometry; };
 
+    friend bool operator < (const SymbolFeature& lhs, const SymbolFeature& rhs) {
+        return lhs.sortKey <  rhs.sortKey;
+    }
+
     std::unique_ptr<GeometryTileFeature> feature;
     GeometryCollection geometry;
     optional<TaggedString> formattedText;
     optional<std::string> icon;
+    float sortKey = 0.0f;
     std::size_t index;
 };