Ensure that when rendering on OpenGL to a texture, the debug geometry is drawn properly in respect to projection matrix flipping. Improve OpenGL debug geometry rendering by rendering it to the intermediate buffer if one exists, so that depth values from the buffer can be correctly used.

Source/Engine/Graphics/View.cpp

@@ -555,20 +555,25 @@ void View::Render()
     // Render
     ExecuteRenderPathCommands();
     
-    #ifdef URHO3D_OPENGL
-    if (camera_)
-        camera_->SetFlipVertical(false);
-    #endif
+    // After executing all commands, reset rendertarget & state for debug geometry rendering
+    // Use the last rendertarget (before blitting) so that OpenGL deferred rendering can have benefit of proper depth buffer
+    // values; after a blit to backbuffer the same depth buffer would not be available any longer
+    graphics_->SetRenderTarget(0, currentRenderTarget_);
+    for (unsigned i = 1; i < MAX_RENDERTARGETS; ++i)
+        graphics_->SetRenderTarget(i, (RenderSurface*)0);
+    graphics_->SetDepthStencil(GetDepthStencil(currentRenderTarget_));
+    IntVector2 rtSizeNow = graphics_->GetRenderTargetDimensions();
+    IntRect viewport = (currentRenderTarget_ == renderTarget_) ? viewRect_ : IntRect(0, 0, rtSizeNow.x_,
+        rtSizeNow.y_);
+    graphics_->SetViewport(viewport);
     
+    graphics_->SetFillMode(FILL_SOLID);
+    graphics_->SetClipPlane(false);
     graphics_->SetDepthBias(0.0f, 0.0f);
     graphics_->SetScissorTest(false);
     graphics_->SetStencilTest(false);
     graphics_->ResetStreamFrequencies();
     
-    // Run framebuffer blitting if necessary
-    if (currentRenderTarget_ != renderTarget_)
-        BlitFramebuffer(static_cast<Texture2D*>(currentRenderTarget_->GetParentTexture()), renderTarget_, true);
-    
     // Draw the associated debug geometry now if enabled
     if (drawDebug_ && octree_ && camera_)
     {
@@ -580,6 +585,15 @@ void View::Render()
         }
     }
     
+    #ifdef URHO3D_OPENGL
+    if (camera_)
+        camera_->SetFlipVertical(false);
+    #endif
+    
+    // Run framebuffer blitting if necessary
+    if (currentRenderTarget_ != renderTarget_)
+        BlitFramebuffer(static_cast<Texture2D*>(currentRenderTarget_->GetParentTexture()), renderTarget_, true);
+    
     // "Forget" the scene, camera, octree and zone after rendering
     scene_ = 0;
     camera_ = 0;
@@ -1539,15 +1553,6 @@ void View::ExecuteRenderPathCommands()
                 viewportModified = true;
         }
     }
-    
-    // After executing all commands, reset rendertarget for debug geometry rendering
-    graphics_->SetRenderTarget(0, renderTarget_);
-    for (unsigned i = 1; i < MAX_RENDERTARGETS; ++i)
-        graphics_->SetRenderTarget(i, (RenderSurface*)0);
-    graphics_->SetDepthStencil(GetDepthStencil(renderTarget_));
-    graphics_->SetViewport(viewRect_);
-    graphics_->SetFillMode(FILL_SOLID);
-    graphics_->SetClipPlane(false);
 }
 
 void View::SetRenderTargets(RenderPathCommand& command)
@@ -1582,11 +1587,11 @@ void View::SetRenderTargets(RenderPathCommand& command)
     // When rendering to the final destination rendertarget, use the actual viewport. Otherwise texture rendertargets will be
     // viewport-sized, so they should use their full size as the viewport
     IntVector2 rtSizeNow = graphics_->GetRenderTargetDimensions();
-    IntRect viewPort = (graphics_->GetRenderTarget(0) == renderTarget_) ? viewRect_ : IntRect(0, 0, rtSizeNow.x_,
+    IntRect viewport = (graphics_->GetRenderTarget(0) == renderTarget_) ? viewRect_ : IntRect(0, 0, rtSizeNow.x_,
         rtSizeNow.y_);
     
     graphics_->SetDepthStencil(GetDepthStencil(graphics_->GetRenderTarget(0)));
-    graphics_->SetViewport(viewPort);
+    graphics_->SetViewport(viewport);
     graphics_->SetColorWrite(true);
 }