cc: Implement unified BeginFrame on aura

ui/compositor/compositor.h

 // Copyright (c) 2012 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 UI_COMPOSITOR_COMPOSITOR_H_
 #define UI_COMPOSITOR_COMPOSITOR_H_
 
 #include <string>
 
 #include "base/containers/hash_tables.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
 #include "base/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "cc/output/begin_frame_args.h"
 #include "cc/surfaces/surface_sequence.h"
 #include "cc/trees/layer_tree_host_client.h"
 #include "cc/trees/layer_tree_host_single_thread_client.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "ui/base/compositor/compositor_begin_frame_observer.h"
 #include "ui/compositor/compositor_animation_observer.h"
 #include "ui/compositor/compositor_export.h"
 #include "ui/compositor/compositor_observer.h"
 #include "ui/compositor/layer_animator_collection.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/size.h"
 #include "ui/gfx/vector2d.h"
 
 namespace base {
 class MessageLoopProxy;
@@ skipping 186 matching lines @@
   // Compositor does not own observers. It is the responsibility of the
   // observer to remove itself when it is done observing.
   void AddObserver(CompositorObserver* observer);
   void RemoveObserver(CompositorObserver* observer);
   bool HasObserver(const CompositorObserver* observer) const;
 
   void AddAnimationObserver(CompositorAnimationObserver* observer);
   void RemoveAnimationObserver(CompositorAnimationObserver* observer);
   bool HasAnimationObserver(const CompositorAnimationObserver* observer) const;
 
+  void AddBeginFrameObserver(
+      CompositorBeginFrameObserver* observer,
+      const cc::BeginFrameArgs& last_begin_frame_args_sent_to_observer);
+  void RemoveBeginFrameObserver(CompositorBeginFrameObserver* observer);
+
   // Creates a compositor lock. Returns NULL if it is not possible to lock at
   // this time (i.e. we're waiting to complete a previous unlock).
   scoped_refptr<CompositorLock> GetCompositorLock();
 
   // Internal functions, called back by command-buffer contexts on swap buffer
   // events.
 
   // Signals swap has been posted.
   void OnSwapBuffersPosted();
 
@@ skipping 14 matching lines @@
                            float top_controls_delta) override {}
   void ApplyViewportDeltas(const gfx::Vector2d& scroll_delta,
                            float page_scale,
                            float top_controls_delta) override {}
   void RequestNewOutputSurface(bool fallback) override;
   void DidInitializeOutputSurface() override {}
   void WillCommit() override {}
   void DidCommit() override;
   void DidCommitAndDrawFrame() override;
   void DidCompleteSwapBuffers() override;
+  void SendBeginFramesToChildren(const cc::BeginFrameArgs& args) override;
 
   // cc::LayerTreeHostSingleThreadClient implementation.
   void DidPostSwapBuffers() override;
   void DidAbortSwapBuffers() override;
 
   bool IsLocked() { return compositor_lock_ != NULL; }
 
   const cc::LayerTreeDebugState& GetLayerTreeDebugState() const;
   void SetLayerTreeDebugState(const cc::LayerTreeDebugState& debug_state);
   const cc::RendererSettings& GetRendererSettings() const;
 
   LayerAnimatorCollection* layer_animator_collection() {
     return &layer_animator_collection_;
   }
 
   cc::SurfaceIdAllocator* surface_id_allocator() {
     return surface_id_allocator_.get();
   }
 
  private:
   friend class base::RefCounted<Compositor>;
   friend class CompositorLock;
 
   // Called by CompositorLock.
   void UnlockCompositor();
 
   // Called to release any pending CompositorLock
   void CancelCompositorLock();
 
+  // Request scheduling of next BeginFrame to LayerTreeHost.
+  void SetChildrenNeedBeginFrames(bool need_begin_frame);
+
   gfx::Size size_;
 
   ui::ContextFactory* context_factory_;
 
   // The root of the Layer tree drawn by this compositor.
   Layer* root_layer_;
 
   ObserverList<CompositorObserver> observer_list_;
   ObserverList<CompositorAnimationObserver> animation_observer_list_;
+  ObserverList<CompositorBeginFrameObserver> begin_frame_observer_list_;
 
   gfx::AcceleratedWidget widget_;
   scoped_ptr<cc::SurfaceIdAllocator> surface_id_allocator_;
   scoped_refptr<cc::Layer> root_web_layer_;
   scoped_ptr<cc::LayerTreeHost> host_;
   scoped_refptr<base::MessageLoopProxy> compositor_thread_loop_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
   // The manager of vsync parameters for this compositor.
   scoped_refptr<CompositorVSyncManager> vsync_manager_;
 
   // The device scale factor of the monitor that this compositor is compositing
   // layers on.
   float device_scale_factor_;
 
   int last_started_frame_;
   int last_ended_frame_;
 
   bool disable_schedule_composite_;
 
   CompositorLock* compositor_lock_;
 
   LayerAnimatorCollection layer_animator_collection_;
 
+  // Used to send to any new CompositorBeginFrameObserver immediately.

[mithro-old, 2014/12/16 10:50:58]

BTW Do we actually want this functionality?

[simonhong, 2014/12/16 15:13:30]

I think this is useful when new observer is added.
With this, new observer can deliver BeginFrame without waiting next BeginFrame
if this is still effective.

+  cc::BeginFrameArgs missed_begin_frame_args_;
+
   base::WeakPtrFactory<Compositor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Compositor);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_COMPOSITOR_H_