wg_engine: fixed resource leaks

issue: https://github.com/thorvg/thorvg/issues/2808

examples/Example.h

@@ -438,7 +438,7 @@ struct WgWindow : Window
 
     virtual ~WgWindow()
     {
-        //wgpuSurfaceRelease(surface);
+        wgpuSurfaceRelease(surface);
         wgpuInstanceRelease(instance);
     }
 

src/renderer/tvgWgCanvas.cpp

@@ -40,7 +40,7 @@ struct WgCanvas::Impl
 /************************************************************************/
 
 #ifdef THORVG_WG_RASTER_SUPPORT
-WgCanvas::WgCanvas() : Canvas(WgRenderer::gen()), pImpl(new Impl)
+WgCanvas::WgCanvas() : Canvas(WgRenderer::gen()), pImpl(nullptr)
 #else
 WgCanvas::WgCanvas() : Canvas(nullptr), pImpl(nullptr)
 #endif

src/renderer/wg_engine/tvgWgCommon.cpp

@@ -60,6 +60,7 @@ void WgContext::release()
     releaseSampler(samplerLinearRepeat);
     releaseSampler(samplerNearestRepeat);
     releaseBuffer(bufferIndexFan);
+    releaseQueue(queue);
 }
 
 
@@ -258,3 +259,11 @@ void WgContext::releaseBuffer(WGPUBuffer& buffer)
         buffer = nullptr;
     }
 }
+
+void WgContext::releaseQueue(WGPUQueue queue)
+{
+    if (queue) {
+        wgpuQueueRelease(queue);
+        queue = nullptr;
+    }
+}

src/renderer/wg_engine/tvgWgCommon.h

@@ -63,6 +63,7 @@ struct WgContext {
     void releaseTextureView(WGPUTextureView& textureView);
     void releaseTexture(WGPUTexture& texture);
     void releaseSampler(WGPUSampler& sampler);
+    void releaseQueue(WGPUQueue queue);
 
     // create buffer objects (return true, if buffer handle was changed)
     bool allocateBufferUniform(WGPUBuffer& buffer, const void* data, uint64_t size);

src/renderer/wg_engine/tvgWgRenderer.cpp

@@ -59,6 +59,7 @@ void WgRenderer::release()
         adapter = nullptr;
         gpuOwner = false;
     }
+    releaseSurfaceTexture();
 }
 
 
@@ -246,13 +247,24 @@ bool WgRenderer::clear()
 }
 
 
+void WgRenderer::releaseSurfaceTexture()
+{
+    if (surfaceTexture.texture) {
+        wgpuTextureRelease(surfaceTexture.texture);
+        surfaceTexture.texture = nullptr;
+    }
+}
+
+
 bool WgRenderer::sync()
 {
     disposeObjects();
     if (!surface) return false;
-    // get current texture
-    WGPUSurfaceTexture surfaceTexture{};
+
+    releaseSurfaceTexture();
+
     wgpuSurfaceGetCurrentTexture(surface, &surfaceTexture);
+
     WGPUTextureView dstView = mContext.createTextureView(surfaceTexture.texture);
 
     // create command encoder

src/renderer/wg_engine/tvgWgRenderer.h

@@ -67,6 +67,9 @@ private:
     void initialize();
     void release();
     void disposeObjects();
+    void releaseSurfaceTexture();
+
+    WGPUSurfaceTexture surfaceTexture{};
 
     WGPUCommandEncoder mCommandEncoder{};
     WgRenderDataShapePool mRenderDataShapePool;