cc/frame_rate_controller.h

   1 // Copyright 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CC_FRAME_RATE_CONTROLLER_H_
   6 #define CC_FRAME_RATE_CONTROLLER_H_
   7
   8 #include "base/memory/ref_counted.h"
   9 #include "base/memory/scoped_ptr.h"
  10 #include "base/memory/weak_ptr.h"
  11 #include "base/time.h"
  12 #include "cc/cc_export.h"
  13
  14 namespace cc {
  15
  16 class Thread;
  17 class TimeSource;
  18
  19 class CC_EXPORT FrameRateControllerClient {
  20 public:
  21     // Throttled is true when we have a maximum number of frames pending.
  22     virtual void vsyncTick(bool throttled) = 0;
  23
  24 protected:
  25     virtual ~FrameRateControllerClient() {}
  26 };
  27
  28 class FrameRateControllerTimeSourceAdapter;
  29
  30 class CC_EXPORT FrameRateController {
  31 public:
  32     explicit FrameRateController(scoped_refptr<TimeSource>);
  33     // Alternate form of FrameRateController with unthrottled frame-rate.
  34     explicit FrameRateController(Thread*);
  35     virtual ~FrameRateController();
  36
  37     void setClient(FrameRateControllerClient* client) { m_client = client; }
  38
  39     void setActive(bool);
  40
  41     // Use the following methods to adjust target frame rate.
  42     //
  43     // Multiple frames can be in-progress, but for every didBeginFrame, a
  44     // didFinishFrame should be posted.
  45     //
  46     // If the rendering pipeline crashes, call didAbortAllPendingFrames.
  47     void didBeginFrame();
  48     void didFinishFrame();
  49     void didAbortAllPendingFrames();
  50     void setMaxFramesPending(int); // 0 for unlimited.
  51
  52     // This returns null for unthrottled frame-rate.
  53     base::TimeTicks nextTickTime();
  54
  55     void setTimebaseAndInterval(base::TimeTicks timebase, base::TimeDelta interval);
  56     void setSwapBuffersCompleteSupported(bool);
  57
  58 protected:
  59     friend class FrameRateControllerTimeSourceAdapter;
  60     void onTimerTick();
  61
  62     void postManualTick();
  63     void manualTick();
  64
  65     FrameRateControllerClient* m_client;
  66     int m_numFramesPending;
  67     int m_maxFramesPending;
  68     scoped_refptr<TimeSource> m_timeSource;
  69     scoped_ptr<FrameRateControllerTimeSourceAdapter> m_timeSourceClientAdapter;
  70     bool m_active;
  71     bool m_swapBuffersCompleteSupported;
  72
  73     // Members for unthrottled frame-rate.
  74     bool m_isTimeSourceThrottling;
  75     base::WeakPtrFactory<FrameRateController> m_weakFactory;
  76     Thread* m_thread;
  77
  78     DISALLOW_COPY_AND_ASSIGN(FrameRateController);
  79 };
  80
  81 }  // namespace cc
  82
  83 #endif  // CC_FRAME_RATE_CONTROLLER_H_