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 "cc/base/cc_export.h"
  10
  11 namespace cc {
  12
  13 struct CC_EXPORT BeginFrameArgs {
  14   // Creates an invalid set of values.
  15   BeginFrameArgs();
  16
  17   // You should be able to find all instances where a BeginFrame has been
  18   // created by searching for "BeginFrameArgs::Create".
  19   static BeginFrameArgs Create(base::TimeTicks frame_time,
  20                                base::TimeTicks deadline,
  21                                base::TimeDelta interval);
  22   static BeginFrameArgs CreateForSynchronousCompositor();
  23   static BeginFrameArgs CreateForTesting();
  24   static BeginFrameArgs CreateExpiredForTesting();
  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 DefaultDeadlineAdjustment();
  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   base::TimeTicks frame_time;
  43   base::TimeTicks deadline;
  44   base::TimeDelta interval;
  45
  46  private:
  47   BeginFrameArgs(base::TimeTicks frame_time,
  48                  base::TimeTicks deadline,
  49                  base::TimeDelta interval);
  50 };
  51
  52 }  // namespace cc
  53
  54 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_