[core] Use hand-rolled RTTI

28 files changed, 104 insertions, 26 deletions

diff --git a/src/mbgl/renderer/bucket.hpp b/src/mbgl/renderer/bucket.hpp
index 9af511a03e..f48593ae49 100644
--- a/src/mbgl/renderer/bucket.hpp
+++ b/src/mbgl/renderer/bucket.hpp
@@ -2,6 +2,7 @@
 
 #include <mbgl/util/noncopyable.hpp>
 #include <mbgl/tile/geometry_tile_data.hpp>
+#include <mbgl/style/layer_type.hpp>
 
 #include <atomic>
 
@@ -15,9 +16,27 @@ class RenderLayer;
 
 class Bucket : private util::noncopyable {
 public:
-    Bucket() = default;
+    Bucket(style::LayerType layerType_)
+        : layerType(layerType_) {
+    }
+
     virtual ~Bucket() = default;
 
+    // Check whether this bucket is of the given subtype.
+    template <class T>
+    bool is() const;
+
+    // Dynamically cast this bucket to the given subtype.
+    template <class T>
+    T* as() {
+        return is<T>() ? reinterpret_cast<T*>(this) : nullptr;
+    }
+
+    template <class T>
+    const T* as() const {
+        return is<T>() ? reinterpret_cast<const T*>(this) : nullptr;
+    }
+
     // Feature geometries are also used to populate the feature index.
     // Obtaining these is a costly operation, so we do it only once, and
     // pass-by-const-ref the geometries as a second parameter.
@@ -39,6 +58,7 @@ public:
     }
 
 protected:
+    style::LayerType layerType;
     std::atomic<bool> uploaded { false };
 };
 
diff --git a/src/mbgl/renderer/buckets/circle_bucket.cpp b/src/mbgl/renderer/buckets/circle_bucket.cpp
index c442b661de..d07c1f8dbe 100644
--- a/src/mbgl/renderer/buckets/circle_bucket.cpp
+++ b/src/mbgl/renderer/buckets/circle_bucket.cpp
@@ -11,7 +11,8 @@ namespace mbgl {
 using namespace style;
 
 CircleBucket::CircleBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers)
-    : mode(parameters.mode) {
+    : Bucket(LayerType::Circle),
+      mode(parameters.mode) {
     for (const auto& layer : layers) {
         paintPropertyBinders.emplace(
             std::piecewise_construct,
diff --git a/src/mbgl/renderer/buckets/circle_bucket.hpp b/src/mbgl/renderer/buckets/circle_bucket.hpp
index 78b6351bcb..3c5f96fb15 100644
--- a/src/mbgl/renderer/buckets/circle_bucket.hpp
+++ b/src/mbgl/renderer/buckets/circle_bucket.hpp
@@ -37,4 +37,9 @@ public:
     const MapMode mode;
 };
 
+template <>
+inline bool Bucket::is<CircleBucket>() const {
+    return layerType == style::LayerType::Circle;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/fill_bucket.cpp b/src/mbgl/renderer/buckets/fill_bucket.cpp
index 110db887a1..14be98c3af 100644
--- a/src/mbgl/renderer/buckets/fill_bucket.cpp
+++ b/src/mbgl/renderer/buckets/fill_bucket.cpp
@@ -27,7 +27,8 @@ using namespace style;
 
 struct GeometryTooLongException : std::exception {};
 
-FillBucket::FillBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers) {
+FillBucket::FillBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers)
+    : Bucket(LayerType::Fill) {
     for (const auto& layer : layers) {
         paintPropertyBinders.emplace(
             std::piecewise_construct,
diff --git a/src/mbgl/renderer/buckets/fill_bucket.hpp b/src/mbgl/renderer/buckets/fill_bucket.hpp
index a50e1971f5..20b65da39c 100644
--- a/src/mbgl/renderer/buckets/fill_bucket.hpp
+++ b/src/mbgl/renderer/buckets/fill_bucket.hpp
@@ -39,4 +39,9 @@ public:
     std::map<std::string, FillProgram::PaintPropertyBinders> paintPropertyBinders;
 };
 
+template <>
+inline bool Bucket::is<FillBucket>() const {
+    return layerType == style::LayerType::Fill;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/fill_extrusion_bucket.cpp b/src/mbgl/renderer/buckets/fill_extrusion_bucket.cpp
index 4fcc761280..c6dba38db1 100644
--- a/src/mbgl/renderer/buckets/fill_extrusion_bucket.cpp
+++ b/src/mbgl/renderer/buckets/fill_extrusion_bucket.cpp
@@ -34,7 +34,8 @@ using namespace style;
 
 struct GeometryTooLongException : std::exception {};
 
-FillExtrusionBucket::FillExtrusionBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers) {
+FillExtrusionBucket::FillExtrusionBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers)
+    : Bucket(LayerType::FillExtrusion) {
     for (const auto& layer : layers) {
         paintPropertyBinders.emplace(std::piecewise_construct,
                                      std::forward_as_tuple(layer->getID()),
diff --git a/src/mbgl/renderer/buckets/fill_extrusion_bucket.hpp b/src/mbgl/renderer/buckets/fill_extrusion_bucket.hpp
index d57265ab16..ed98e01292 100644
--- a/src/mbgl/renderer/buckets/fill_extrusion_bucket.hpp
+++ b/src/mbgl/renderer/buckets/fill_extrusion_bucket.hpp
@@ -34,4 +34,9 @@ public:
     std::unordered_map<std::string, FillExtrusionProgram::PaintPropertyBinders> paintPropertyBinders;
 };
 
+template <>
+inline bool Bucket::is<FillExtrusionBucket>() const {
+    return layerType == style::LayerType::FillExtrusion;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/heatmap_bucket.cpp b/src/mbgl/renderer/buckets/heatmap_bucket.cpp
index a185e04ad2..eff0c60280 100644
--- a/src/mbgl/renderer/buckets/heatmap_bucket.cpp
+++ b/src/mbgl/renderer/buckets/heatmap_bucket.cpp
@@ -11,7 +11,8 @@ namespace mbgl {
 using namespace style;
 
 HeatmapBucket::HeatmapBucket(const BucketParameters& parameters, const std::vector<const RenderLayer*>& layers)
-    : mode(parameters.mode) {
+    : Bucket(LayerType::Heatmap),
+      mode(parameters.mode) {
     for (const auto& layer : layers) {
         paintPropertyBinders.emplace(
             std::piecewise_construct,
diff --git a/src/mbgl/renderer/buckets/heatmap_bucket.hpp b/src/mbgl/renderer/buckets/heatmap_bucket.hpp
index 3b9f1edb81..86b6f10296 100644
--- a/src/mbgl/renderer/buckets/heatmap_bucket.hpp
+++ b/src/mbgl/renderer/buckets/heatmap_bucket.hpp
@@ -37,4 +37,9 @@ public:
     const MapMode mode;
 };
 
+template <>
+inline bool Bucket::is<HeatmapBucket>() const {
+    return layerType == style::LayerType::Heatmap;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/hillshade_bucket.cpp b/src/mbgl/renderer/buckets/hillshade_bucket.cpp
index 00b9536894..3ca217a840 100644
--- a/src/mbgl/renderer/buckets/hillshade_bucket.cpp
+++ b/src/mbgl/renderer/buckets/hillshade_bucket.cpp
@@ -8,10 +8,14 @@ namespace mbgl {
 
 using namespace style;
 
-HillshadeBucket::HillshadeBucket(PremultipliedImage&& image_, Tileset::DEMEncoding encoding): demdata(image_, encoding) {
+HillshadeBucket::HillshadeBucket(PremultipliedImage&& image_, Tileset::DEMEncoding encoding)
+    : Bucket(LayerType::Hillshade),
+      demdata(image_, encoding) {
 }
 
-HillshadeBucket::HillshadeBucket(DEMData&& demdata_) : demdata(std::move(demdata_)) {
+HillshadeBucket::HillshadeBucket(DEMData&& demdata_)
+    : Bucket(LayerType::Hillshade),
+      demdata(std::move(demdata_)) {
 }
 
 const DEMData& HillshadeBucket::getDEMData() const {
diff --git a/src/mbgl/renderer/buckets/hillshade_bucket.hpp b/src/mbgl/renderer/buckets/hillshade_bucket.hpp
index 5335f7ceda..c9e435c661 100644
--- a/src/mbgl/renderer/buckets/hillshade_bucket.hpp
+++ b/src/mbgl/renderer/buckets/hillshade_bucket.hpp
@@ -56,4 +56,9 @@ private:
     bool prepared = false;
 };
 
+template <>
+inline bool Bucket::is<HillshadeBucket>() const {
+    return layerType == style::LayerType::Hillshade;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/line_bucket.cpp b/src/mbgl/renderer/buckets/line_bucket.cpp
index a96518df38..a10551a7d2 100644
--- a/src/mbgl/renderer/buckets/line_bucket.cpp
+++ b/src/mbgl/renderer/buckets/line_bucket.cpp
@@ -14,7 +14,8 @@ using namespace style;
 LineBucket::LineBucket(const BucketParameters& parameters,
                        const std::vector<const RenderLayer*>& layers,
                        const style::LineLayoutProperties::Unevaluated& layout_)
-    : layout(layout_.evaluate(PropertyEvaluationParameters(parameters.tileID.overscaledZ))),
+    : Bucket(LayerType::Line),
+      layout(layout_.evaluate(PropertyEvaluationParameters(parameters.tileID.overscaledZ))),
       overscaling(parameters.tileID.overscaleFactor()),
       zoom(parameters.tileID.overscaledZ) {
     for (const auto& layer : layers) {
diff --git a/src/mbgl/renderer/buckets/line_bucket.hpp b/src/mbgl/renderer/buckets/line_bucket.hpp
index 4fb77c377e..8fe7184941 100644
--- a/src/mbgl/renderer/buckets/line_bucket.hpp
+++ b/src/mbgl/renderer/buckets/line_bucket.hpp
@@ -64,4 +64,9 @@ private:
     float getLineWidth(const RenderLineLayer& layer) const;
 };
 
+template <>
+inline bool Bucket::is<LineBucket>() const {
+    return layerType == style::LayerType::Line;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/raster_bucket.cpp b/src/mbgl/renderer/buckets/raster_bucket.cpp
index a66dd42d74..45cf351d8e 100644
--- a/src/mbgl/renderer/buckets/raster_bucket.cpp
+++ b/src/mbgl/renderer/buckets/raster_bucket.cpp
@@ -7,12 +7,14 @@ namespace mbgl {
 
 using namespace style;
 
-RasterBucket::RasterBucket(PremultipliedImage&& image_) {
-    image = std::make_shared<PremultipliedImage>(std::move(image_));
+RasterBucket::RasterBucket(PremultipliedImage&& image_)
+    : Bucket(LayerType::Raster),
+      image(std::make_shared<PremultipliedImage>(std::move(image_))) {
 }
 
-RasterBucket::RasterBucket(std::shared_ptr<PremultipliedImage> image_): image(image_) {
-
+RasterBucket::RasterBucket(std::shared_ptr<PremultipliedImage> image_)
+    : Bucket(LayerType::Raster),
+      image(image_) {
 }
 
 void RasterBucket::upload(gl::Context& context) {
diff --git a/src/mbgl/renderer/buckets/raster_bucket.hpp b/src/mbgl/renderer/buckets/raster_bucket.hpp
index 3800eadec8..84b618a83d 100644
--- a/src/mbgl/renderer/buckets/raster_bucket.hpp
+++ b/src/mbgl/renderer/buckets/raster_bucket.hpp
@@ -38,4 +38,9 @@ public:
     optional<gl::IndexBuffer<gl::Triangles>> indexBuffer;
 };
 
+template <>
+inline bool Bucket::is<RasterBucket>() const {
+    return layerType == style::LayerType::Raster;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/buckets/symbol_bucket.cpp b/src/mbgl/renderer/buckets/symbol_bucket.cpp
index 51fcd2437c..0a1530ae74 100644
--- a/src/mbgl/renderer/buckets/symbol_bucket.cpp
+++ b/src/mbgl/renderer/buckets/symbol_bucket.cpp
@@ -20,7 +20,8 @@ SymbolBucket::SymbolBucket(style::SymbolLayoutProperties::PossiblyEvaluated layo
                            bool sortFeaturesByY_,
                            const std::string bucketName_,
                            const std::vector<SymbolInstance>&& symbolInstances_)
-    : layout(std::move(layout_)),
+    : Bucket(LayerType::Symbol),
+      layout(std::move(layout_)),
       sdfIcons(sdfIcons_),
       iconsNeedLinear(iconsNeedLinear_ || iconSize.isDataDriven() || !iconSize.isZoomConstant()),
       sortFeaturesByY(sortFeaturesByY_),
diff --git a/src/mbgl/renderer/buckets/symbol_bucket.hpp b/src/mbgl/renderer/buckets/symbol_bucket.hpp
index e4aaf5ba30..4f01cf4e1c 100644
--- a/src/mbgl/renderer/buckets/symbol_bucket.hpp
+++ b/src/mbgl/renderer/buckets/symbol_bucket.hpp
@@ -138,4 +138,9 @@ public:
     std::shared_ptr<std::vector<size_t>> featureSortOrder;
 };
 
+template <>
+inline bool Bucket::is<SymbolBucket>() const {
+    return layerType == style::LayerType::Symbol;
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/layers/render_circle_layer.cpp b/src/mbgl/renderer/layers/render_circle_layer.cpp
index b1b4d22561..ce63ada770 100644
--- a/src/mbgl/renderer/layers/render_circle_layer.cpp
+++ b/src/mbgl/renderer/layers/render_circle_layer.cpp
@@ -56,7 +56,7 @@ void RenderCircleLayer::render(PaintParameters& parameters, RenderSource*) {
     const bool pitchWithMap = evaluated.get<CirclePitchAlignment>() == AlignmentType::Map;
 
     for (const RenderTile& tile : renderTiles) {
-        auto bucket_ = dynamic_cast<CircleBucket*>(tile.tile.getBucket(*baseImpl));
+        auto bucket_ = tile.tile.getBucket<CircleBucket>(*baseImpl);
         if (!bucket_) {
             continue;
         }
diff --git a/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp b/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
index d37f6f528b..2f720284fc 100644
--- a/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
+++ b/src/mbgl/renderer/layers/render_fill_extrusion_layer.cpp
@@ -100,7 +100,7 @@ void RenderFillExtrusionLayer::render(PaintParameters& parameters, RenderSource*
 
         if (evaluated.get<FillExtrusionPattern>().from.empty()) {
             for (const RenderTile& tile : renderTiles) {
-                auto bucket_ = dynamic_cast<FillExtrusionBucket*>(tile.tile.getBucket(*baseImpl));
+                auto bucket_ = tile.tile.getBucket<FillExtrusionBucket>(*baseImpl);
                 if (!bucket_) {
                     continue;
                 }
@@ -131,7 +131,7 @@ void RenderFillExtrusionLayer::render(PaintParameters& parameters, RenderSource*
             parameters.imageManager.bind(parameters.context, 0);
 
             for (const RenderTile& tile : renderTiles) {
-                auto bucket_ = dynamic_cast<FillExtrusionBucket*>(tile.tile.getBucket(*baseImpl));
+                auto bucket_ = tile.tile.getBucket<FillExtrusionBucket>(*baseImpl);
                 if (!bucket_) {
                     continue;
                 }
diff --git a/src/mbgl/renderer/layers/render_fill_layer.cpp b/src/mbgl/renderer/layers/render_fill_layer.cpp
index cce4399262..f03eb66c88 100644
--- a/src/mbgl/renderer/layers/render_fill_layer.cpp
+++ b/src/mbgl/renderer/layers/render_fill_layer.cpp
@@ -61,7 +61,7 @@ bool RenderFillLayer::hasTransition() const {
 void RenderFillLayer::render(PaintParameters& parameters, RenderSource*) {
     if (evaluated.get<FillPattern>().from.empty()) {
         for (const RenderTile& tile : renderTiles) {
-            auto bucket_ = dynamic_cast<FillBucket*>(tile.tile.getBucket(*baseImpl));
+            auto bucket_ = tile.tile.getBucket<FillBucket>(*baseImpl);
             if (!bucket_) {
                 continue;
             }
@@ -149,7 +149,7 @@ void RenderFillLayer::render(PaintParameters& parameters, RenderSource*) {
         parameters.imageManager.bind(parameters.context, 0);
 
         for (const RenderTile& tile : renderTiles) {
-            auto bucket_ = dynamic_cast<FillBucket*>(tile.tile.getBucket(*baseImpl));
+            auto bucket_ = tile.tile.getBucket<FillBucket>(*baseImpl);
             if (!bucket_) {
                 continue;
             }
diff --git a/src/mbgl/renderer/layers/render_heatmap_layer.cpp b/src/mbgl/renderer/layers/render_heatmap_layer.cpp
index d2c6f6d970..c9ca477cbb 100644
--- a/src/mbgl/renderer/layers/render_heatmap_layer.cpp
+++ b/src/mbgl/renderer/layers/render_heatmap_layer.cpp
@@ -83,7 +83,7 @@ void RenderHeatmapLayer::render(PaintParameters& parameters, RenderSource*) {
         parameters.context.clear(Color{ 0.0f, 0.0f, 0.0f, 1.0f }, {}, {});
 
         for (const RenderTile& tile : renderTiles) {
-            auto bucket_ = dynamic_cast<HeatmapBucket*>(tile.tile.getBucket(*baseImpl));
+            auto bucket_ = tile.tile.getBucket<HeatmapBucket>(*baseImpl);
             if (!bucket_) {
                 continue;
             }
diff --git a/src/mbgl/renderer/layers/render_hillshade_layer.cpp b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
index 0edc8737c1..25eef98fcf 100644
--- a/src/mbgl/renderer/layers/render_hillshade_layer.cpp
+++ b/src/mbgl/renderer/layers/render_hillshade_layer.cpp
@@ -114,7 +114,7 @@ void RenderHillshadeLayer::render(PaintParameters& parameters, RenderSource* src
     matrix::translate(mat, mat, 0, -util::EXTENT, 0);
 
     for (const RenderTile& tile : renderTiles) {
-        auto bucket_ = dynamic_cast<HillshadeBucket*>(tile.tile.getBucket(*baseImpl));
+        auto bucket_ = tile.tile.getBucket<HillshadeBucket>(*baseImpl);
         if (!bucket_) {
             continue;
         }
diff --git a/src/mbgl/renderer/layers/render_line_layer.cpp b/src/mbgl/renderer/layers/render_line_layer.cpp
index ea51705792..4b6ea35e67 100644
--- a/src/mbgl/renderer/layers/render_line_layer.cpp
+++ b/src/mbgl/renderer/layers/render_line_layer.cpp
@@ -58,7 +58,7 @@ void RenderLineLayer::render(PaintParameters& parameters, RenderSource*) {
     }
 
     for (const RenderTile& tile : renderTiles) {
-        auto bucket_ = dynamic_cast<LineBucket*>(tile.tile.getBucket(*baseImpl));
+        auto bucket_ = tile.tile.getBucket<LineBucket>(*baseImpl);
         if (!bucket_) {
             continue;
         }
diff --git a/src/mbgl/renderer/layers/render_raster_layer.cpp b/src/mbgl/renderer/layers/render_raster_layer.cpp
index 13f2f5e38c..e2524697b5 100644
--- a/src/mbgl/renderer/layers/render_raster_layer.cpp
+++ b/src/mbgl/renderer/layers/render_raster_layer.cpp
@@ -142,7 +142,7 @@ void RenderRasterLayer::render(PaintParameters& parameters, RenderSource* source
         }
     } else {
         for (const RenderTile& tile : renderTiles) {
-            auto bucket_ = dynamic_cast<RasterBucket*>(tile.tile.getBucket(*baseImpl));
+            auto bucket_ = tile.tile.getBucket<RasterBucket>(*baseImpl);
             if (!bucket_) {
                 continue;
             }
diff --git a/src/mbgl/renderer/layers/render_symbol_layer.cpp b/src/mbgl/renderer/layers/render_symbol_layer.cpp
index d397ffd724..63fcb6cfd5 100644
--- a/src/mbgl/renderer/layers/render_symbol_layer.cpp
+++ b/src/mbgl/renderer/layers/render_symbol_layer.cpp
@@ -75,7 +75,7 @@ void RenderSymbolLayer::render(PaintParameters& parameters, RenderSource*) {
     }
 
     for (const RenderTile& tile : renderTiles) {
-        auto bucket_ = dynamic_cast<SymbolBucket*>(tile.tile.getBucket(*baseImpl));
+        auto bucket_ = tile.tile.getBucket<SymbolBucket>(*baseImpl);
         if (!bucket_) {
             continue;
         }
diff --git a/src/mbgl/text/cross_tile_symbol_index.cpp b/src/mbgl/text/cross_tile_symbol_index.cpp
index 58dcda46f5..98b9af1f94 100644
--- a/src/mbgl/text/cross_tile_symbol_index.cpp
+++ b/src/mbgl/text/cross_tile_symbol_index.cpp
@@ -178,7 +178,7 @@ bool CrossTileSymbolIndex::addLayer(RenderSymbolLayer& symbolLayer, float lng) {
             continue;
         }
 
-        auto bucket = dynamic_cast<SymbolBucket*>(renderTile.tile.getBucket(*symbolLayer.baseImpl));
+        auto bucket = renderTile.tile.getBucket<SymbolBucket>(*symbolLayer.baseImpl);
         if (!bucket) {
             continue;
         }
diff --git a/src/mbgl/text/placement.cpp b/src/mbgl/text/placement.cpp
index 96c1873e33..16dd94b374 100644
--- a/src/mbgl/text/placement.cpp
+++ b/src/mbgl/text/placement.cpp
@@ -51,7 +51,7 @@ void Placement::placeLayer(RenderSymbolLayer& symbolLayer, const mat4& projMatri
         assert(dynamic_cast<GeometryTile*>(&renderTile.tile));
         GeometryTile& geometryTile = static_cast<GeometryTile&>(renderTile.tile);
 
-        auto bucket = dynamic_cast<SymbolBucket*>(geometryTile.getBucket(*symbolLayer.baseImpl));
+        auto bucket = renderTile.tile.getBucket<SymbolBucket>(*symbolLayer.baseImpl);
         if (!bucket) {
             continue;
         }
@@ -232,7 +232,7 @@ void Placement::updateLayerOpacities(RenderSymbolLayer& symbolLayer) {
             continue;
         }
 
-        auto bucket = dynamic_cast<SymbolBucket*>(renderTile.tile.getBucket(*symbolLayer.baseImpl));
+        auto bucket = renderTile.tile.getBucket<SymbolBucket>(*symbolLayer.baseImpl);
         if (!bucket) {
             continue;
         }
diff --git a/src/mbgl/tile/tile.hpp b/src/mbgl/tile/tile.hpp
index 2182ec722f..5cf74abff5 100644
--- a/src/mbgl/tile/tile.hpp
+++ b/src/mbgl/tile/tile.hpp
@@ -48,6 +48,12 @@ public:
     virtual void upload(gl::Context&) = 0;
     virtual Bucket* getBucket(const style::Layer::Impl&) const = 0;
 
+    template <class T>
+    T* getBucket(const style::Layer::Impl& layer) const {
+        Bucket* bucket = getBucket(layer);
+        return bucket ? bucket->as<T>() : nullptr;
+    }
+
     virtual void setShowCollisionBoxes(const bool) {}
     virtual void setLayers(const std::vector<Immutable<style::Layer::Impl>>&) {}
     virtual void setMask(TileMask&&) {}