Implement transform/clip support for 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 <string>
 #include <vector>
 
@@ skipping 162 matching lines @@
   // Must be called if and only if PrepareToDraw was called.
   void DidDrawAllLayers(const FrameData& frame);
 
   const LayerTreeSettings& settings() const { return settings_; }
 
   // Returns the currently visible viewport size in DIP. This value excludes
   // the URL bar and non-overlay scrollbars.
   gfx::SizeF VisibleViewportSize() const;
 
   // RendererClient implementation
+  virtual gfx::Rect DeviceViewport() const OVERRIDE;
  private:
-  virtual gfx::Size DeviceViewportSize() const OVERRIDE;
   virtual float DeviceScaleFactor() const OVERRIDE;
   virtual const LayerTreeSettings& Settings() const OVERRIDE;
  public:
   virtual void DidLoseOutputSurface() OVERRIDE;
   virtual void OnSwapBuffersComplete() OVERRIDE;
   virtual void SetFullRootLayerDamage() OVERRIDE;
   virtual void SetManagedMemoryPolicy(const ManagedMemoryPolicy& policy)
       OVERRIDE;
   virtual void EnforceManagedMemoryPolicy(const ManagedMemoryPolicy& policy)
       OVERRIDE;
   virtual bool HasImplThread() const OVERRIDE;
   virtual bool ShouldClearRootRenderPass() const OVERRIDE;
   virtual CompositorFrameMetadata MakeCompositorFrameMetadata() const OVERRIDE;
   virtual bool AllowPartialSwap() const OVERRIDE;
 
   // TileManagerClient implementation.
   virtual void ScheduleManageTiles() OVERRIDE;
   virtual void DidInitializeVisibleTile() OVERRIDE;
   virtual bool ShouldForceTileUploadsRequiredForActivationToComplete() const
       OVERRIDE;
 
   // OutputSurfaceClient implementation.
   virtual void SetNeedsRedrawRect(gfx::Rect rect) OVERRIDE;
   virtual void OnVSyncParametersChanged(base::TimeTicks timebase,
                                         base::TimeDelta interval) OVERRIDE;
   virtual void BeginFrame(base::TimeTicks frame_time)
       OVERRIDE;
   virtual void OnSendFrameToParentCompositorAck(const CompositorFrameAck& ack)
       OVERRIDE;
+  virtual void SetExternalDrawConstraints(const gfx::Transform& transform,
+                                          gfx::Rect viewport) OVERRIDE;
 
   // Called from LayerTreeImpl.
   void OnCanDrawStateChangedForTree();
 
   // Implementation
   bool CanDraw();
   OutputSurface* output_surface() const { return output_surface_.get(); }
 
   std::string LayerTreeAsText() const;
   std::string LayerTreeAsJson() const;
@@ skipping 40 matching lines @@
 
   void SetViewportSize(gfx::Size device_viewport_size);
   gfx::Size device_viewport_size() const { return device_viewport_size_; }
 
   void SetOverdrawBottomHeight(float overdraw_bottom_height);
   float overdraw_bottom_height() const { return overdraw_bottom_height_; }
 
   void SetDeviceScaleFactor(float device_scale_factor);
   float device_scale_factor() const { return device_scale_factor_; }
 
+  gfx::Rect DeviceClip() const;
+  const gfx::Transform& DeviceTransform() const;
+
   scoped_ptr<ScrollAndScaleSet> ProcessScrollDeltas();
 
   bool needs_animate_layers() const {
     return !animation_registrar_->active_animation_controllers().empty();
   }
 
   void SendManagedMemoryStats(
       size_t memory_visible_bytes,
       size_t memory_visible_and_nearby_bytes,
       size_t memory_use_bytes);
@@ skipping 171 matching lines @@
   scoped_ptr<LayerTreeImpl> recycle_tree_;
 
   InputHandlerClient* input_handler_client_;
   bool did_lock_scrolling_layer_;
   bool should_bubble_scrolls_;
   bool wheel_scrolling_;
   // The optional delegate for the root layer scroll offset.
   LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate_;
   LayerTreeSettings settings_;
   LayerTreeDebugState debug_state_;
-  gfx::Size device_viewport_size_;
-  float overdraw_bottom_height_;
-  float device_scale_factor_;
   bool visible_;
   ManagedMemoryPolicy managed_memory_policy_;
 
   gfx::Vector2dF accumulated_root_overscroll_;
   gfx::Vector2dF current_fling_velocity_;
 
   bool pinch_gesture_active_;
   gfx::Point previous_pinch_anchor_;
 
   // This is set by AnimateLayers() and used by UpdateAnimationState()
@@ skipping 13 matching lines @@
   scoped_ptr<DebugRectHistory> debug_rect_history_;
 
   // The maximum memory that would be used by the prioritized resource
   // manager, if there were no limit on memory usage.
   size_t max_memory_needed_bytes_;
 
   size_t last_sent_memory_visible_bytes_;
   size_t last_sent_memory_visible_and_nearby_bytes_;
   size_t last_sent_memory_use_bytes_;
 
+  // Viewport size passed in from the main thread, in physical pixels.
+  gfx::Size device_viewport_size_;
+
+  // Conversion factor from CSS pixels to physical pixels when
+  // pageScaleFactor=1.
+  float device_scale_factor_;
+
+  // Vertical amount of the viewport size that's known to covered by a
+  // browser-side UI element, such as an on-screen-keyboard.  This affects
+  // scrollable size since we want to still be able to scroll to the bottom of
+  // the page when the keyboard is up.
+  float overdraw_bottom_height_;
+
+  // Optional top-level constraints that can be set by the OutputSurface.  The
+  // external_viewport_'s size takes precedence over device_viewport_size_ for
+  // DrawQuad generation and Renderer; however, device_viewport_size_ is still
+  // used for scrollable size.
+  gfx::Transform external_transform_;
+  gfx::Rect external_viewport_;
+
   gfx::Rect viewport_damage_rect_;
 
   base::TimeTicks current_frame_timeticks_;
   base::Time current_frame_time_;
 
   scoped_ptr<AnimationRegistrar> animation_registrar_;
 
   RenderingStatsInstrumentation* rendering_stats_instrumentation_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_