wined3d: Do not specify the viewport origin upside down when doing offscreen rendering.

dlls/wined3d/device.c

@@ -5134,6 +5134,10 @@ static HRESULT WINAPI IWineD3DDeviceImpl_SetRenderTarget(IWineD3DDevice *iface,
         viewport.MaxZ   = 1.0f;
         viewport.MinZ   = 0.0f;
         IWineD3DDeviceImpl_SetViewport(iface, &viewport);
+        /* Make sure the viewport state is dirty, because the render_offscreen thing affects it.
+         * SetViewport may catch NOP viewport changes, which would occur when switching between equally sized targets
+         */
+        IWineD3DDeviceImpl_MarkStateDirty(This, STATE_VIEWPORT);
 
         /* Activate the new render target for now. This shouldn't stay here, but is needed until all methods using gl activate the
          * ctx properly.

dlls/wined3d/state.c

@@ -3015,11 +3015,17 @@ static void vertexdeclaration(DWORD state, IWineD3DStateBlockImpl *stateblock, W
 static void viewport(DWORD state, IWineD3DStateBlockImpl *stateblock, WineD3DContext *context) {
     glDepthRange(stateblock->viewport.MinZ, stateblock->viewport.MaxZ);
     checkGLcall("glDepthRange");
-    /* Note: GL requires lower left, DirectX supplies upper left */
-    /* TODO: replace usage of renderTarget with context management */
-    glViewport(stateblock->viewport.X,
-               (((IWineD3DSurfaceImpl *)stateblock->wineD3DDevice->render_targets[0])->currentDesc.Height - (stateblock->viewport.Y + stateblock->viewport.Height)),
-               stateblock->viewport.Width, stateblock->viewport.Height);
+    /* Note: GL requires lower left, DirectX supplies upper left. This is reversed when using offscreen rendering
+     */
+    if(stateblock->wineD3DDevice->render_offscreen) {
+        glViewport(stateblock->viewport.X,
+                   stateblock->viewport.Y,
+                   stateblock->viewport.Width, stateblock->viewport.Height);
+    } else {
+        glViewport(stateblock->viewport.X,
+                   (((IWineD3DSurfaceImpl *)stateblock->wineD3DDevice->render_targets[0])->currentDesc.Height - (stateblock->viewport.Y + stateblock->viewport.Height)),
+                   stateblock->viewport.Width, stateblock->viewport.Height);
+    }
 
     checkGLcall("glViewport");