• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/time.h"
12 #include "cc/base/cc_export.h"
13 #include "cc/output/begin_frame_args.h"
14 
15 namespace base { class SingleThreadTaskRunner; }
16 
17 namespace cc {
18 
19 class TimeSource;
20 class FrameRateController;
21 
22 class CC_EXPORT FrameRateControllerClient {
23  protected:
~FrameRateControllerClient()24   virtual ~FrameRateControllerClient() {}
25 
26  public:
27   // Throttled is true when we have a maximum number of frames pending.
28   virtual void FrameRateControllerTick(bool throttled,
29                                        const BeginFrameArgs& args) = 0;
30 };
31 
32 class FrameRateControllerTimeSourceAdapter;
33 
34 // The FrameRateController is used in cases where we self-tick (i.e. BeginFrame
35 // is not sent by a parent compositor.
36 class CC_EXPORT FrameRateController {
37  public:
38   explicit FrameRateController(scoped_refptr<TimeSource> timer);
39   // Alternate form of FrameRateController with unthrottled frame-rate.
40   explicit FrameRateController(base::SingleThreadTaskRunner* task_runner);
41   virtual ~FrameRateController();
42 
SetClient(FrameRateControllerClient * client)43   void SetClient(FrameRateControllerClient* client) { client_ = client; }
44 
45   // Returns a valid BeginFrame on activation to potentially be used
46   // retroactively.
47   BeginFrameArgs SetActive(bool active);
48 
IsActive()49   bool IsActive() { return active_; }
50 
51   // Use the following methods to adjust target frame rate.
52   //
53   // Multiple frames can be in-progress, but for every DidSwapBuffers, a
54   // DidFinishFrame should be posted.
55   //
56   // If the rendering pipeline crashes, call DidAbortAllPendingFrames.
57   void DidSwapBuffers();
58   void DidSwapBuffersComplete();
59   void DidAbortAllPendingFrames();
60   void SetMaxSwapsPending(int max_swaps_pending);  // 0 for unlimited.
MaxSwapsPending()61   int MaxSwapsPending() const { return max_swaps_pending_; }
NumSwapsPendingForTesting()62   int NumSwapsPendingForTesting() const { return num_frames_pending_; }
63 
64   void SetTimebaseAndInterval(base::TimeTicks timebase,
65                               base::TimeDelta interval);
66   void SetDeadlineAdjustment(base::TimeDelta delta);
67 
68  protected:
69   friend class FrameRateControllerTimeSourceAdapter;
70   void OnTimerTick();
71 
72   void PostManualTick();
73   void ManualTick();
74 
75     // This returns null for unthrottled frame-rate.
76   base::TimeTicks NextTickTime();
77   // This returns now for unthrottled frame-rate.
78   base::TimeTicks LastTickTime();
79 
80   FrameRateControllerClient* client_;
81   int num_frames_pending_;
82   int max_swaps_pending_;
83   base::TimeDelta interval_;
84   base::TimeDelta deadline_adjustment_;
85   scoped_refptr<TimeSource> time_source_;
86   scoped_ptr<FrameRateControllerTimeSourceAdapter> time_source_client_adapter_;
87   bool active_;
88 
89   // Members for unthrottled frame-rate.
90   bool is_time_source_throttling_;
91   bool manual_tick_pending_;
92   base::SingleThreadTaskRunner* task_runner_;
93   base::WeakPtrFactory<FrameRateController> weak_factory_;
94 
95  private:
96   DISALLOW_COPY_AND_ASSIGN(FrameRateController);
97 };
98 
99 }  // namespace cc
100 
101 #endif  // CC_SCHEDULER_FRAME_RATE_CONTROLLER_H_
102