Tiling priorities in Android Webview.

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TREES_LAYER_TREE_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <list>
 #include <set>
 #include <string>
@@ skipping 204 matching lines @@
 
   // Resets all of the trees to an empty state.
   void ResetTreesForTesting();
 
   DrawMode GetDrawMode() const;
 
   // Viewport size in draw space: this size is in physical pixels and is used
   // for draw properties, tilings, quads and render passes.
   gfx::Size DrawViewportSize() const;
 
+  // Viewport rect in screen space used for tiling prioritization.
+  gfx::Rect ExternalTilingRect() const;

[enne (OOO), 2014/07/24 19:25:19]

bikeshed: "TilingRect" is a really ambiguous phrase in cc.  It's not always
external, either.  Maybe call this DeviceViewportRect(ForTiling) or
ViewportRectForTilePriority that you call it in PictureLayerImpl?

+  const gfx::Transform& ExternalTilingTransform() const;
+
   // Viewport size for scrolling and fixed-position compensation. This value
   // excludes the URL bar and non-overlay scrollbars and is in DIP (and
   // invariant relative to page scale).
   gfx::SizeF UnscaledScrollableViewportSize() const;
   float VerticalAdjust() const;
 
   // RendererClient implementation.
   virtual void SetFullRootLayerDamage() OVERRIDE;
   virtual void RunOnDemandRasterTask(Task* on_demand_raster_task) OVERRIDE;
 
@@ skipping 11 matching lines @@
   virtual void DeferredInitialize() OVERRIDE;
   virtual void ReleaseGL() OVERRIDE;
   virtual void CommitVSyncParameters(base::TimeTicks timebase,
                                      base::TimeDelta interval) OVERRIDE;
   virtual void SetNeedsRedrawRect(const gfx::Rect& rect) OVERRIDE;
   virtual void BeginFrame(const BeginFrameArgs& args) OVERRIDE;
   virtual void SetExternalDrawConstraints(
       const gfx::Transform& transform,
       const gfx::Rect& viewport,
       const gfx::Rect& clip,
+      const gfx::Rect& external_tiling_rect,
+      const gfx::Transform& external_tiling_transform,
       bool resourceless_software_draw) OVERRIDE;
   virtual void DidLoseOutputSurface() OVERRIDE;
   virtual void DidSwapBuffers() OVERRIDE;
   virtual void DidSwapBuffersComplete() OVERRIDE;
   virtual void ReclaimResources(const CompositorFrameAck* ack) OVERRIDE;
   virtual void SetMemoryPolicy(const ManagedMemoryPolicy& policy) OVERRIDE;
   virtual void SetTreeActivationCallback(const base::Closure& callback)
       OVERRIDE;
 
   // Called from LayerTreeImpl.
@@ skipping 393 matching lines @@
   float overdraw_bottom_height_;
 
   // Optional top-level constraints that can be set by the OutputSurface.
   // - external_transform_ applies a transform above the root layer
   // - external_viewport_ is used DrawProperties, tile management and
   // glViewport/window projection matrix.
   // - external_clip_ specifies a top-level clip rect
   gfx::Transform external_transform_;
   gfx::Rect external_viewport_;
   gfx::Rect external_clip_;
+  gfx::Rect external_tiling_rect_;
+  gfx::Transform external_tiling_transform_;
   bool resourceless_software_draw_;
 
   gfx::Rect viewport_damage_rect_;
 
   base::TimeTicks current_frame_timeticks_;
 
   // Expected time between two begin impl frame calls.
   base::TimeDelta begin_impl_frame_interval_;
 
   scoped_ptr<AnimationRegistrar> animation_registrar_;
@@ skipping 17 matching lines @@
   size_t transfer_buffer_memory_limit_;
 
   std::vector<PictureLayerImpl*> picture_layers_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_