[core] Implement CrossFadedDataDrivenProperty to add support for feature expressions in `*-pattern` properties

1 files changed, 14 insertions, 0 deletions

diff --git a/src/mbgl/renderer/layers/render_fill_layer.hpp b/src/mbgl/renderer/layers/render_fill_layer.hpp
index bd195fb828..5a3c05387d 100644
--- a/src/mbgl/renderer/layers/render_fill_layer.hpp
+++ b/src/mbgl/renderer/layers/render_fill_layer.hpp
@@ -3,18 +3,26 @@
 #include <mbgl/renderer/render_layer.hpp>
 #include <mbgl/style/layers/fill_layer_impl.hpp>
 #include <mbgl/style/layers/fill_layer_properties.hpp>
+#include <mbgl/layout/pattern_layout.hpp>
 
 namespace mbgl {
 
+class FillBucket;
+
 class RenderFillLayer: public RenderLayer {
 public:
+    using StyleLayerImpl = style::FillLayer::Impl;
+    using PatternProperty = style::FillPattern;
+
     RenderFillLayer(Immutable<style::FillLayer::Impl>);
     ~RenderFillLayer() final = default;
 
     void transition(const TransitionParameters&) override;
     void evaluate(const PropertyEvaluationParameters&) override;
     bool hasTransition() const override;
+    bool hasCrossfade() const override;
     void render(PaintParameters&, RenderSource*) override;
+    style::FillPaintProperties::PossiblyEvaluated paintProperties() const;
 
     bool queryIntersectsFeature(
             const GeometryCoordinates&,
@@ -26,11 +34,17 @@ public:
 
     std::unique_ptr<Bucket> createBucket(const BucketParameters&, const std::vector<const RenderLayer*>&) const override;
 
+    std::unique_ptr<PatternLayout<FillBucket>>
+    createLayout(const BucketParameters&, const std::vector<const RenderLayer*>&, std::unique_ptr<GeometryTileLayer>, ImageDependencies&) const;
+
     // Paint properties
     style::FillPaintProperties::Unevaluated unevaluated;
     style::FillPaintProperties::PossiblyEvaluated evaluated;
 
     const style::FillLayer::Impl& impl() const;
+private:
+    CrossfadeParameters crossfade;
+
 };
 
 template <>