Added CircleBucket class stub

Part of #1740.

src/mbgl/map/tile_parser.cpp

@@ -6,6 +6,7 @@
 #include <mbgl/map/sprite.hpp>
 #include <mbgl/renderer/fill_bucket.hpp>
 #include <mbgl/renderer/line_bucket.hpp>
+#include <mbgl/renderer/circle_bucket.hpp>
 #include <mbgl/renderer/symbol_bucket.hpp>
 #include <mbgl/util/constants.hpp>
 #include <mbgl/style/style.hpp>
@@ -112,15 +113,18 @@ std::unique_ptr<Bucket> TileParser::createBucket(const StyleBucket &bucketDesc)
 
     auto layer = geometryTile.getLayer(bucketDesc.source_layer);
     if (layer) {
-        if (bucketDesc.type == StyleLayerType::Fill) {
+        switch (bucketDesc.type) {
+        case StyleLayerType::Fill:
             return createFillBucket(*layer, bucketDesc);
-        } else if (bucketDesc.type == StyleLayerType::Line) {
+        case StyleLayerType::Line:
             return createLineBucket(*layer, bucketDesc);
-        } else if (bucketDesc.type == StyleLayerType::Symbol) {
+        case StyleLayerType::Circle:
+            return createCircleBucket(*layer, bucketDesc);
+        case StyleLayerType::Symbol:
             return createSymbolBucket(*layer, bucketDesc);
-        } else if (bucketDesc.type == StyleLayerType::Raster) {
+        case StyleLayerType::Raster:
             return nullptr;
-        } else {
+        default:
             Log::Warning(Event::ParseTile, "unknown bucket render type for layer '%s' (source layer '%s')",
                     bucketDesc.name.c_str(), bucketDesc.source_layer.c_str());
         }
@@ -177,6 +181,17 @@ std::unique_ptr<Bucket> TileParser::createLineBucket(const GeometryTileLayer& la
     return bucket->hasData() ? std::move(bucket) : nullptr;
 }
 
+std::unique_ptr<Bucket> TileParser::createCircleBucket(const GeometryTileLayer& layer,
+                                                       const StyleBucket& bucket_desc) {
+    auto bucket = std::make_unique<CircleBucket>(tile.circleVertexBuffer,
+                                                 tile.triangleElementsBuffer);
+
+    // Circle does not have layout properties to apply.
+
+    addBucketGeometries(bucket, layer, bucket_desc.filter);
+    return bucket->hasData() ? std::move(bucket) : nullptr;
+}
+
 std::unique_ptr<Bucket> TileParser::createSymbolBucket(const GeometryTileLayer& layer,
                                                        const StyleBucket& bucket_desc) {
     auto bucket = std::make_unique<SymbolBucket>(*tile.getCollision(), tile.id.overscaling);

src/mbgl/map/tile_parser.hpp

@@ -53,6 +53,7 @@ class TileParser : private util::noncopyable {
     std::unique_ptr<Bucket> createBucket(const StyleBucket&);
     std::unique_ptr<Bucket> createFillBucket(const GeometryTileLayer&, const StyleBucket&);
     std::unique_ptr<Bucket> createLineBucket(const GeometryTileLayer&, const StyleBucket&);
+    std::unique_ptr<Bucket> createCircleBucket(const GeometryTileLayer&, const StyleBucket&);
     std::unique_ptr<Bucket> createSymbolBucket(const GeometryTileLayer&, const StyleBucket&);
 
     template <class Bucket>

src/mbgl/renderer/circle_bucket.cpp

@@ -0,0 +1,35 @@
+#include <mbgl/renderer/circle_bucket.hpp>
+
+using namespace mbgl;
+
+CircleBucket::CircleBucket(CircleVertexBuffer& vertexBuffer,
+                           TriangleElementsBuffer& elementsBuffer)
+    : vertexBuffer_(vertexBuffer)
+    , elementsBuffer_(elementsBuffer) {
+}
+
+CircleBucket::~CircleBucket() {
+    // Do not remove. header file only contains forward definitions to unique pointers.
+}
+
+void CircleBucket::upload() {
+    vertexBuffer_.upload();
+    elementsBuffer_.upload();
+    uploaded = true;
+}
+
+void CircleBucket::render(Painter& /* painter */,
+                        const StyleLayer& /* layer_desc */,
+                        const TileID& /* id */,
+                        const mat4& /* matrix */) {
+    // XXX Just a stub for now.
+    //painter.renderCircle(*this, layer_desc, id, matrix);
+}
+
+bool CircleBucket::hasData() const {
+    return !triangleGroups_.empty();
+}
+
+void CircleBucket::addGeometry(const GeometryCollection& /* geometryCollection */) {
+    // XXX Just a stub for now.
+}

src/mbgl/renderer/circle_bucket.hpp

@@ -0,0 +1,41 @@
+#ifndef MBGL_RENDERER_CIRCLE_BUCKET
+#define MBGL_RENDERER_CIRCLE_BUCKET
+
+#include <mbgl/renderer/bucket.hpp>
+
+#include <mbgl/map/geometry_tile.hpp>
+
+#include <mbgl/geometry/elements_buffer.hpp>
+#include <mbgl/geometry/circle_buffer.hpp>
+
+#include <mbgl/style/style_bucket.hpp>
+#include <mbgl/style/style_layout.hpp>
+
+namespace mbgl {
+
+class CircleVertexBuffer;
+class CircleElementsBuffer;
+
+class CircleBucket : public Bucket {
+    using TriangleGroup = ElementGroup<3>;
+
+public:
+    CircleBucket(CircleVertexBuffer &vertexBuffer, TriangleElementsBuffer &elementsBuffer);
+    ~CircleBucket() override;
+
+    void upload() override;
+    void render(Painter&, const StyleLayer&, const TileID&, const mat4&) override;
+
+    bool hasData() const;
+    void addGeometry(const GeometryCollection&);
+
+private:
+    CircleVertexBuffer& vertexBuffer_;
+    TriangleElementsBuffer& elementsBuffer_;
+
+    std::vector<std::unique_ptr<TriangleGroup>> triangleGroups_;
+};
+
+} // namespace mbgl
+
+#endif // MBGL_RENDERER_CIRCLE_BUCKET