[core] Reuse RasterBucket for ImageSource

src/mbgl/gl/index_buffer.hpp

@@ -24,6 +24,7 @@ public:
     std::size_t byteSize() const { return v.size() * sizeof(uint16_t); }
 
     bool empty() const { return v.empty(); }
+    void clear() { v.clear(); }
     const uint16_t* data() const { return v.data(); }
 
 private:

src/mbgl/gl/vertex_buffer.hpp

@@ -26,6 +26,7 @@ public:
     std::size_t byteSize() const { return v.size() * sizeof(Vertex); }
 
     bool empty() const { return v.empty(); }
+    void clear() { v.clear(); }
     const Vertex* data() const { return v.data(); }
 
 private:

src/mbgl/renderer/buckets/raster_bucket.cpp

@@ -12,10 +12,6 @@ using namespace style;
 RasterBucket::RasterBucket(UnassociatedImage&& image_) : image(std::move(image_)) {
 }
 
-RasterBucket::RasterBucket(RasterBucket&& other) : image(std::move(other.image)) {
-    uploaded = false;
-}
-
 void RasterBucket::upload(gl::Context& context) {
     texture = context.createTexture(image);
     if (!vertices.empty()) {
@@ -25,6 +21,15 @@ void RasterBucket::upload(gl::Context& context) {
     uploaded = true;
 }
 
+void RasterBucket::clear() {
+    vertexBuffer = {};
+    indexBuffer = {};
+    segments.clear();
+    vertices.clear();
+    indices.clear();
+    
+    uploaded = false;
+}
 void RasterBucket::render(Painter& painter,
                           PaintParameters& parameters,
                           const RenderLayer& layer,

src/mbgl/renderer/buckets/raster_bucket.hpp

@@ -14,7 +14,6 @@ namespace mbgl {
 class RasterBucket : public Bucket {
 public:
     RasterBucket(UnassociatedImage&&);
-    RasterBucket(RasterBucket&&);
 
     void upload(gl::Context&) override;
     void render(Painter&, PaintParameters&, const RenderLayer&, const RenderTile&) override;
@@ -24,6 +23,7 @@ public:
                 const mat4& matrix);
     bool hasData() const override;
 
+    void clear();
     UnassociatedImage image;
     optional<gl::Texture> texture;
 

src/mbgl/renderer/sources/render_image_source.cpp

@@ -137,8 +137,7 @@ void RenderImageSource::updateTiles(const TileParameters& parameters) {
         }
         bucket = std::make_unique<RasterBucket>(std::move(img));
     } else {
-        // Reuse the bucket
-        bucket = std::make_unique<RasterBucket>(std::move(*bucket));
+        bucket->clear();
     }
 
     // Set Bucket Vertices, Indices, and segments

test/gl/bucket.test.cpp

@@ -3,9 +3,11 @@
 #include <mbgl/renderer/buckets/circle_bucket.hpp>
 #include <mbgl/renderer/buckets/fill_bucket.hpp>
 #include <mbgl/renderer/buckets/line_bucket.hpp>
+#include <mbgl/renderer/buckets/raster_bucket.hpp>
 #include <mbgl/renderer/buckets/symbol_bucket.hpp>
 #include <mbgl/renderer/bucket_parameters.hpp>
 #include <mbgl/style/layers/symbol_layer_properties.hpp>
+#include <mbgl/gl/context.hpp>
 
 #include <mbgl/map/mode.hpp>
 
@@ -36,3 +38,17 @@ TEST(Buckets, SymbolBucket) {
     ASSERT_FALSE(bucket.hasTextData());
     ASSERT_FALSE(bucket.hasCollisionBoxData());
 }
+
+TEST(Buckets, RasterBucket) {
+    gl::Context context;
+    UnassociatedImage rgba({ 1, 1 });
+
+    RasterBucket bucket = { std::move(rgba) };
+    ASSERT_TRUE(bucket.needsUpload());
+
+    bucket.upload(context);
+    ASSERT_FALSE(bucket.needsUpload());
+
+    bucket.clear();
+    ASSERT_TRUE(bucket.needsUpload());
+}