1 files changed, 16 insertions, 9 deletions

diff --git a/src/mbgl/renderer/layers/render_symbol_layer.cpp b/src/mbgl/renderer/layers/render_symbol_layer.cpp
index 634e0cf01b..95df9435f9 100644
--- a/src/mbgl/renderer/layers/render_symbol_layer.cpp
+++ b/src/mbgl/renderer/layers/render_symbol_layer.cpp
@@ -306,24 +306,29 @@ void drawText(const DrawFn& draw,
             });
     }
 }
+
+inline const SymbolLayer::Impl& impl(const Immutable<style::Layer::Impl>& impl) {
+    return static_cast<const SymbolLayer::Impl&>(*impl);
+}
+
 } // namespace
 
 RenderSymbolLayer::RenderSymbolLayer(Immutable<style::SymbolLayer::Impl> _impl)
-    : RenderLayer(std::move(_impl)),
-      unevaluated(impl().paint.untransitioned()) {
+    : RenderLayer(makeMutable<SymbolLayerProperties>(std::move(_impl))),
+      unevaluated(impl(baseImpl).paint.untransitioned()) {
 }
 
-const style::SymbolLayer::Impl& RenderSymbolLayer::impl() const {
-    return static_cast<const style::SymbolLayer::Impl&>(*baseImpl);
-}
+RenderSymbolLayer::~RenderSymbolLayer() = default;
 
 void RenderSymbolLayer::transition(const TransitionParameters& parameters) {
-    unevaluated = impl().paint.transitioned(parameters, std::move(unevaluated));
+    unevaluated = impl(baseImpl).paint.transitioned(parameters, std::move(unevaluated));
 }
 
 void RenderSymbolLayer::evaluate(const PropertyEvaluationParameters& parameters) {
-    evaluated = unevaluated.evaluate(parameters);
-
+    auto properties = makeMutable<SymbolLayerProperties>(
+        staticImmutableCast<SymbolLayer::Impl>(baseImpl),
+        unevaluated.evaluate(parameters));
+    const auto& evaluated = properties->evaluated;
     auto hasIconOpacity = evaluated.get<style::IconColor>().constantOr(Color::black()).a > 0 ||
                           evaluated.get<style::IconHaloColor>().constantOr(Color::black()).a > 0;
     auto hasTextOpacity = evaluated.get<style::TextColor>().constantOr(Color::black()).a > 0 ||
@@ -332,6 +337,7 @@ void RenderSymbolLayer::evaluate(const PropertyEvaluationParameters& parameters)
     passes = ((evaluated.get<style::IconOpacity>().constantOr(1) > 0 && hasIconOpacity && iconSize > 0)
               || (evaluated.get<style::TextOpacity>().constantOr(1) > 0 && hasTextOpacity && textSize > 0))
              ? RenderPass::Translucent : RenderPass::None;
+    evaluatedProperties = std::move(properties);
 }
 
 bool RenderSymbolLayer::hasTransition() const {
@@ -363,7 +369,7 @@ void RenderSymbolLayer::render(PaintParameters& parameters, RenderSource*) {
         return;
     }
 
-    const bool sortFeaturesByKey = !impl().layout.get<SymbolSortKey>().isUndefined();
+    const bool sortFeaturesByKey = !impl(baseImpl).layout.get<SymbolSortKey>().isUndefined();
     std::set<RenderableSegment> renderableSegments;
 
     const auto draw = [&parameters, this] (auto& programInstance,
@@ -598,6 +604,7 @@ void RenderSymbolLayer::setRenderTiles(RenderTiles tiles, const TransformState&
 
 void RenderSymbolLayer::updateBucketPaintProperties(Bucket* bucket) const {
     assert(bucket->supportsLayer(*baseImpl));
+    const auto& evaluated = static_cast<const SymbolLayerProperties&>(*evaluatedProperties).evaluated;
     static_cast<SymbolBucket*>(bucket)->updatePaintProperties(getID(), evaluated);
 }