cc: Make scheduling be driven by vsync for android webview.

android_webview/browser/browser_view_renderer.h

 // Copyright (c) 2013 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 ANDROID_WEBVIEW_BROWSER_BROWSER_VIEW_RENDERER_H_
 #define ANDROID_WEBVIEW_BROWSER_BROWSER_VIEW_RENDERER_H_
 
 #include "android_webview/browser/parent_compositor_draw_constraints.h"
 #include "android_webview/browser/shared_renderer_state.h"
 #include "base/callback.h"
@@ skipping 31 matching lines @@
   // |global_visible_rect| is the intersection of the view size and the window
   // in window coordinates.
   void PrepareToDraw(const gfx::Vector2d& scroll,
                      const gfx::Rect& global_visible_rect);
 
   // Main handlers for view drawing. A false return value indicates no new
   // frame is produced.
   bool OnDrawHardware();
   bool OnDrawSoftware(SkCanvas* canvas);
 
+  void OnVSync(base::TimeTicks frame_time, base::TimeDelta vsync_period);
+
   // CapturePicture API methods.
   skia::RefPtr<SkPicture> CapturePicture(int width, int height);
   void EnableOnNewPicture(bool enabled);
 
   void ClearView();
 
   // View update notifications.
   void SetIsPaused(bool paused);
   void SetViewVisibility(bool visible);
   void SetWindowVisibility(bool visible);
@@ skipping 15 matching lines @@
   gfx::Size size() const { return size_; }
   void ReleaseHardware();
 
   void TrimMemory(const int level, const bool visible);
 
   // SynchronousCompositorClient overrides.
   virtual void DidInitializeCompositor(
       content::SynchronousCompositor* compositor) override;
   virtual void DidDestroyCompositor(content::SynchronousCompositor* compositor)
       override;
-  virtual void SetContinuousInvalidate(bool invalidate) override;
+  virtual void SetNeedsVSyncs(bool needs_vsyncs) override;
+  virtual void PostInvalidate() override;
   virtual void DidUpdateContent() override;
   virtual gfx::Vector2dF GetTotalRootLayerScrollOffset() override;
   virtual void UpdateRootLayerState(
       const gfx::Vector2dF& total_scroll_offset_dip,
       const gfx::Vector2dF& max_scroll_offset_dip,
       const gfx::SizeF& scrollable_size_dip,
       float page_scale_factor,
       float min_page_scale_factor,
       float max_page_scale_factor) override;
   virtual bool IsExternalFlingActive() const override;
   virtual void DidOverscroll(gfx::Vector2dF accumulated_overscroll,
                              gfx::Vector2dF latest_overscroll_delta,
                              gfx::Vector2dF current_fling_velocity) override;
 
   void UpdateParentDrawConstraints();
-  void DidSkipCommitFrame();
   void InvalidateOnFunctorDestroy();
 
  private:
+  bool CompositeSW(SkCanvas* canvas);
+  scoped_ptr<cc::CompositorFrame> CompositeHw();
+
   void SetTotalRootLayerScrollOffset(gfx::Vector2dF new_value_dip);
-  // Checks the continuous invalidate and block invalidate state, and schedule
-  // invalidates appropriately. If |force_invalidate| is true, then send a view
-  // invalidate regardless of compositor expectation. If |skip_reschedule_tick|
-  // is true and if there is already a pending fallback tick, don't reschedule
-  // them.
-  void EnsureContinuousInvalidation(bool force_invalidate,
-                                    bool skip_reschedule_tick);
-  bool CompositeSW(SkCanvas* canvas);
-  void DidComposite();
-  void DidSkipCompositeInDraw();
   scoped_refptr<base::debug::ConvertableToTraceFormat> RootLayerStateAsValue(
       const gfx::Vector2dF& total_scroll_offset_dip,
       const gfx::SizeF& scrollable_size_dip);
 
-  scoped_ptr<cc::CompositorFrame> CompositeHw();
   void ReturnUnusedResource(scoped_ptr<cc::CompositorFrame> frame);
   void ReturnResourceFromParent();
-
-  // If we call up view invalidate and OnDraw is not called before a deadline,
-  // then we keep ticking the SynchronousCompositor so it can make progress.
-  // Do this in a two stage tick due to native MessageLoop favors delayed task,
-  // so ensure delayed task is inserted only after the draw task returns.
-  void PostFallbackTick();
-  void FallbackTickFired();
-
-  // Force invoke the compositor to run produce a 1x1 software frame that is
-  // immediately discarded. This is a hack to force invoke parts of the
-  // compositor that are not directly exposed here.
-  void ForceFakeCompositeSW();
-
+ 
   gfx::Vector2d max_scroll_offset() const;
 
   size_t CalculateDesiredMemoryPolicy();
+
+  void UpdateNeedsVSyncs();
+
   // For debug tracing or logging. Return the string representation of this
   // view renderer's state.
   std::string ToString() const;
 
   BrowserViewRendererClient* client_;
   SharedRendererState shared_renderer_state_;
   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
 
   content::SynchronousCompositor* compositor_;
 
   bool is_paused_;
   bool view_visible_;
   bool window_visible_;  // Only applicable if |attached_to_window_| is true.
   bool attached_to_window_;
   bool hardware_enabled_;
   float dip_scale_;
   float page_scale_factor_;
   bool on_new_picture_enable_;
   bool clear_view_;
 
   gfx::Vector2d last_on_draw_scroll_offset_;
   gfx::Rect last_on_draw_global_visible_rect_;
 
   // The draw constraints from the parent compositor. These are only used for
   // tiling priority.
   ParentCompositorDrawConstraints parent_draw_constraints_;
 
-  // When true, we should continuously invalidate and keep drawing, for example
+  // When true, we should ask for vsyncs and pass them on, for example
   // to drive animation. This value is set by the compositor and should always
   // reflect the expectation of the compositor and not be reused for other
   // states.
-  bool compositor_needs_continuous_invalidate_;
+  bool compositor_needs_vsyncs_;
 
-  bool invalidate_after_composite_;
-
-  // Used to block additional invalidates while one is already pending.
-  bool block_invalidates_;
-
-  base::CancelableClosure post_fallback_tick_;
-  base::CancelableClosure fallback_tick_fired_;
-  bool fallback_tick_pending_;
+  // This is actually used to decide if we're asking for vsyncs. Sometimes we
+  // want to stop vsync callbacks even if the compositor is asking for them.
+  // e.g. when paused (backgrounded) or window not visible.
+  bool needs_vsyncs_;
 
   gfx::Size size_;
 
   // Current scroll offset in CSS pixels.
   gfx::Vector2dF scroll_offset_dip_;
 
   // Max scroll offset in CSS pixels.
   gfx::Vector2dF max_scroll_offset_dip_;
 
   // Used to prevent rounding errors from accumulating enough to generate
   // visible skew (especially noticeable when scrolling up and down in the same
   // spot over a period of time).
   gfx::Vector2dF overscroll_rounding_error_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserViewRenderer);
 };
 
 }  // namespace android_webview
 
 #endif  // ANDROID_WEBVIEW_BROWSER_BROWSER_VIEW_RENDERER_H_