internal void NotifyTileCacheInvalidated(DocumentCanvasTileCache tileCache, RectInt32 sourceRect)
        {
            base.VerifyAccess();
            int mipLevel = tileCache.MipLevel;

            foreach (DocumentCanvasLayerView view in this.documentCanvasLayerViews.Values)
            {
                if ((mipLevel == 0) || (tileCache.IsHighQuality == GetIsHighQualityScalingEnabled(view.CanvasView)))
                {
                    view.NotifyTileCacheInvalidated(tileCache, sourceRect);
                }
            }
            if (tileCache.IsActive)
            {
                tileCache.ProcessTileRenderQueue();
            }
        }