renderer: delegate the null data handling to engines

src/renderer/gl_engine/tvgGlRenderer.cpp

@@ -864,7 +864,7 @@ bool GlRenderer::sync()
 
 RenderRegion GlRenderer::region(RenderData data)
 {
-    if (currentPass()->isEmpty()) return {};
+    if (!data || currentPass()->isEmpty()) return {};
 
     auto shape = reinterpret_cast<GlShape*>(data);
     auto bounds = shape->geometry.getBounds();

src/renderer/sw_engine/tvgSwRenderer.cpp

@@ -50,7 +50,6 @@ struct SwTask : Task
 
     const RenderRegion& bounds()
     {
-        //Can we skip the synchronization?
         done();
         return bbox;
     }
@@ -488,7 +487,8 @@ bool SwRenderer::blend(BlendMethod method)
 
 RenderRegion SwRenderer::region(RenderData data)
 {
-    return static_cast<SwTask*>(data)->bounds();
+    if (data) return static_cast<SwTask*>(data)->bounds();
+    return {};
 }
 
 

src/renderer/tvgPaint.h

@@ -120,7 +120,6 @@ namespace tvg
         uint8_t unrefx(bool free)
         {
             if (refCnt > 0) --refCnt;
-            else TVGERR("RENDERER", "Corrupted Reference Count!");
 
             if (free && refCnt == 0) {
                 delete(paint);

src/renderer/tvgPicture.h

@@ -265,9 +265,8 @@ struct PictureImpl : Picture
 
     RenderRegion bounds(RenderMethod* renderer)
     {
-        if (impl.rd) return renderer->region(impl.rd);
         if (vector) return vector->pImpl->bounds(renderer);
-        return {};
+        return renderer->region(impl.rd);
     }
 
     Result load(ImageLoader* loader)

src/renderer/tvgShape.h

@@ -115,7 +115,6 @@ struct ShapeImpl : Shape
 
     RenderRegion bounds(RenderMethod* renderer)
     {
-        if (!impl.rd) return {};
         return renderer->region(impl.rd);
     }
 

src/renderer/wg_engine/tvgWgRenderer.cpp

@@ -270,6 +270,7 @@ void WgRenderer::dispose(RenderData data) {
 
 RenderRegion WgRenderer::region(RenderData data)
 {
+    if (!data) return {};
     auto renderData = (WgRenderDataPaint*)data;
     if (renderData->type() == Type::Shape) {
         auto& v1 = renderData->aabb.min;