Dynamically set CAOpenGLLAyer to be asynchronous

content/browser/renderer_host/render_widget_host_view_mac.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 CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 #include <list>
 #include <map>
@@ skipping 417 matching lines @@
   bool can_compose_inline_;
 
   base::scoped_nsobject<CALayer> software_layer_;
 
   // Accelerated compositing structures. These may be dynamically created and
   // destroyed together in Create/DestroyCompositedIOSurfaceAndLayer.
   base::scoped_nsobject<CompositingIOSurfaceLayer> compositing_iosurface_layer_;
   scoped_ptr<CompositingIOSurfaceMac> compositing_iosurface_;
   scoped_refptr<CompositingIOSurfaceContext> compositing_iosurface_context_;
 
+  // Timer used to dynamically transition the compositing layer in and out of
+  // asynchronous mode.
+  base::DelayTimer<RenderWidgetHostViewMac>
+      compositing_iosurface_layer_async_timer_;
+
   // This holds the current software compositing framebuffer, if any.
   scoped_ptr<SoftwareFrameManager> software_frame_manager_;
 
   // Whether to allow overlapping views.
   bool allow_overlapping_views_;
 
   // Whether to use the CoreAnimation path to draw content.
   bool use_core_animation_;
 
   // Latency info to send back when the next frame appears on the
@@ skipping 57 matching lines @@
 
   // Unbind the GL context (if any) that is bound to |cocoa_view_|.
   void ClearBoundContextDrawable();
 
   // Called when a GPU SwapBuffers is received.
   void GotAcceleratedFrame();
 
   // Called when a software DIB is received.
   void GotSoftwareFrame();
 
+  // Called if it has been a quarter-second since a GPU SwapBuffers has been
+  // received. In this case, switch from polling for frames to pushing them.
+  void TimerSinceGotAcceleratedFrameFired();
+
   void OnPluginFocusChanged(bool focused, int plugin_id);
   void OnStartPluginIme();
 
   // Convert |rect| from the views coordinate (upper-left origin) into
   // the OpenGL coordinate (lower-left origin) and scale for HiDPI displays.
   gfx::Rect GetScaledOpenGLPixelRect(const gfx::Rect& rect);
 
   // The associated view. This is weak and is inserted into the view hierarchy
   // to own this RenderWidgetHostViewMac object. Set to nil at the start of the
   // destructor.
@@ skipping 52 matching lines @@
   scoped_ptr<RenderWidgetHostViewFrameSubscriber> frame_subscriber_;
 
   base::WeakPtrFactory<RenderWidgetHostViewMac>
       software_frame_weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_