cc/scheduler/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_SCHEDULER_FRAME_RATE_CONTROLLER_H_
   6 #define CC_SCHEDULER_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/base/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   enum {
  33     DEFAULT_MAX_FRAMES_PENDING = 2
  34   };
  35
  36   explicit FrameRateController(scoped_refptr<TimeSource> timer);
  37   // Alternate form of FrameRateController with unthrottled frame-rate.
  38   explicit FrameRateController(Thread* thread);
  39   virtual ~FrameRateController();
  40
  41   void SetClient(FrameRateControllerClient* client) { client_ = client; }
  42
  43   void SetActive(bool active);
  44
  45   // Use the following methods to adjust target frame rate.
  46   //
  47   // Multiple frames can be in-progress, but for every DidBeginFrame, a
  48   // DidFinishFrame should be posted.
  49   //
  50   // If the rendering pipeline crashes, call DidAbortAllPendingFrames.
  51   void DidBeginFrame();
  52   void DidFinishFrame();
  53   void DidAbortAllPendingFrames();
  54   void SetMaxFramesPending(int max_frames_pending);  // 0 for unlimited.
  55   int MaxFramesPending() const { return max_frames_pending_; }
  56
  57   // This returns null for unthrottled frame-rate.
  58   base::TimeTicks NextTickTime();
  59
  60   // This returns now for unthrottled frame-rate.
  61   base::TimeTicks LastTickTime();
  62
  63   void SetTimebaseAndInterval(base::TimeTicks timebase,
  64                               base::TimeDelta interval);
  65   void SetSwapBuffersCompleteSupported(bool supported);
  66
  67  protected:
  68   friend class FrameRateControllerTimeSourceAdapter;
  69   void OnTimerTick();
  70
  71   void PostManualTick();
  72   void ManualTick();
  73
  74   FrameRateControllerClient* client_;
  75   int num_frames_pending_;
  76   int max_frames_pending_;
  77   scoped_refptr<TimeSource> time_source_;
  78   scoped_ptr<FrameRateControllerTimeSourceAdapter> time_source_client_adapter_;
  79   bool active_;
  80   bool swap_buffers_complete_supported_;
  81
  82   // Members for unthrottled frame-rate.
  83   bool is_time_source_throttling_;
  84   base::WeakPtrFactory<FrameRateController> weak_factory_;
  85   Thread* thread_;
  86
  87   DISALLOW_COPY_AND_ASSIGN(FrameRateController);
  88 };
  89
  90 }  // namespace cc
  91
  92 #endif  // CC_SCHEDULER_FRAME_RATE_CONTROLLER_H_