cc/output/begin_frame_args.h

   1 // Copyright 2013 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_OUTPUT_BEGIN_FRAME_ARGS_H_
   6 #define CC_OUTPUT_BEGIN_FRAME_ARGS_H_
   7
   8 #include "base/time/time.h"
   9 #include "base/values.h"
  10 #include "cc/base/cc_export.h"
  11
  12 namespace cc {
  13
  14 struct CC_EXPORT BeginFrameArgs {
  15   // Creates an invalid set of values.
  16   BeginFrameArgs();
  17
  18   // You should be able to find all instances where a BeginFrame has been
  19   // created by searching for "BeginFrameArgs::Create".
  20   static BeginFrameArgs Create(base::TimeTicks frame_time,
  21                                base::TimeTicks deadline,
  22                                base::TimeDelta interval);
  23   static BeginFrameArgs CreateForSynchronousCompositor(
  24       base::TimeTicks now = base::TimeTicks());
  25
  26   // This is the default delta that will be used to adjust the deadline when
  27   // proper draw-time estimations are not yet available.
  28   static base::TimeDelta DefaultEstimatedParentDrawTime();
  29
  30   // This is the default interval to use to avoid sprinkling the code with
  31   // magic numbers.
  32   static base::TimeDelta DefaultInterval();
  33
  34   // This is the default amount of time after the frame_time to retroactively
  35   // send a BeginFrame that had been skipped. This only has an effect if the
  36   // deadline has passed, since the deadline is also used to trigger BeginFrame
  37   // retroactively.
  38   static base::TimeDelta DefaultRetroactiveBeginFramePeriod();
  39
  40   bool IsValid() const { return interval >= base::TimeDelta(); }
  41
  42   scoped_ptr<base::Value> AsValue() const;
  43
  44   base::TimeTicks frame_time;
  45   base::TimeTicks deadline;
  46   base::TimeDelta interval;
  47
  48  private:
  49   BeginFrameArgs(base::TimeTicks frame_time,
  50                  base::TimeTicks deadline,
  51                  base::TimeDelta interval);
  52 };
  53
  54 }  // namespace cc
  55
  56 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_