[Chromecast] Adding pause/resume operations to VideoPlaneController.

chromecast/media/base/video_plane_controller.h

 // Copyright 2015 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 CHROMECAST_MEDIA_VIDEO_PLANE_CONTROLLER_H_
 #define CHROMECAST_MEDIA_VIDEO_PLANE_CONTROLLER_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
@@ skipping 41 matching lines @@
   // from the last call to this method, it is a no-op.
   void SetDeviceResolution(const Size& resolution);
 
   // Sets graphics hardware plane resolution.  This must be called at least once
   // when the hardware graphics plane resolution (same resolution as
   // gfx::Screen) is known, then later when it changes. If there is no change to
   // the graphics plane resolution from the last call to this method, it is a
   // no-op.
   void SetGraphicsPlaneResolution(const Size& resolution);
 
+  // After Pause is called, no further calls to VideoPlane::SetGeometry will be
+  // made except for any pending calls already scheduled on the media thread.
+  // The Set methods will however update cached parameters that will take
+  // effect once the class is resumed. Safe to call multiple times.
+  // TODO(esum): Handle the case where there are pending calls already on the
+  // media thread. When this returns, the caller needs to know that absolutely
+  // no more SetGeometry calls will be made.
+  void Pause();
+  // Makes class active again. Also resets the video plane by posting a call to
+  // VideoPlane::SetGeometry with most recent resolution and geometry parameters
+  // (assuming they are all set). Safe to call multiple times.
+  void Resume();
+  bool is_paused() const;
+
  private:
   class RateLimitedSetVideoPlaneGeometry;
   friend struct base::DefaultSingletonTraits<VideoPlaneController>;
 
   VideoPlaneController();
   ~VideoPlaneController();
 
   // Check if HaveDataForSetGeometry. If not, this method is a no-op. Otherwise
   // it scales the display rect from graphics to device resolution coordinates.
   // Then posts task to media thread for VideoPlane::SetGeometry.
   void MaybeRunSetGeometry();
   // Checks if all data has been collected to make calls to
   // VideoPlane::SetGeometry.
   bool HaveDataForSetGeometry() const;
 
+  bool is_paused_;
+
   // Current resolutions
   bool have_output_res_;
   bool have_graphics_res_;
   Size output_res_;
   Size graphics_res_;
 
   // Saved video plane parameters (in graphics plane coordinates)
   // for use when screen resolution changes.
   bool have_video_plane_geometry_;
   RectF video_plane_display_rect_;
   VideoPlane::Transform video_plane_transform_;
 
   scoped_refptr<base::SingleThreadTaskRunner> media_task_runner_;
   scoped_refptr<RateLimitedSetVideoPlaneGeometry> video_plane_wrapper_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoPlaneController);
 };
 
 }  // namespace media
 }  // namespace chromecast
 
 #endif  // CHROMECAST_MEDIA_VIDEO_PLANE_CONTROLLER_H_