"Buttery Smooth" Tab Capture.

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 <IOSurface/IOSurfaceAPI.h>
 #include <list>
@@ skipping 356 matching lines @@
   void SetTextInputActive(bool active);
 
   // Sends completed plugin IME notification and text back to the renderer.
   void PluginImeCompositionCompleted(const base::string16& text, int plugin_id);
 
   const std::string& selected_text() const { return selected_text_; }
 
   // Update the IOSurface to be drawn and call setNeedsDisplay on
   // |cocoa_view_|.
   void CompositorSwapBuffers(IOSurfaceID surface_handle,
-                             const gfx::Size& size,
+                             const gfx::Rect& damage_rect,
+                             const gfx::Size& surface_size,
                              float scale_factor,
                              const std::vector<ui::LatencyInfo>& latency_info);
 
   // Called when a GPU error is detected. Posts a task to destroy all
   // compositing state.
   void GotAcceleratedCompositingError();
 
   // Returns true and stores first rectangle for character range if the
   // requested |range| is already cached, otherwise returns false.
   // Exposed for testing.
@@ skipping 221 matching lines @@
 
   // The fullscreen window used for pepper flash.
   base::scoped_nsobject<NSWindow> pepper_fullscreen_window_;
   base::scoped_nsobject<FullscreenWindowManager> fullscreen_window_manager_;
   // Our parent host view, if this is fullscreen.  NULL otherwise.
   RenderWidgetHostViewMac* fullscreen_parent_host_view_;
 
   // Display link for getting vsync info.
   scoped_refptr<DisplayLinkMac> display_link_;
 
+  // The current VSync timebase and interval. This is zero until the first call
+  // to SendVSyncParametersToRenderer(), and refreshed regularly thereafter.
+  base::TimeTicks vsync_timebase_;
+  base::TimeDelta vsync_interval_;
+
   // The current composition character range and its bounds.
   gfx::Range composition_range_;
   std::vector<gfx::Rect> composition_bounds_;
 
   // The current caret bounds.
   gfx::Rect caret_rect_;
 
   // Subscriber that listens to frame presentation events.
   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_