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/memory/ref_counted.h"
   9 #include "base/time/time.h"
  10 #include "base/values.h"
  11 #include "cc/base/cc_export.h"
  12
  13 namespace base {
  14 namespace debug {
  15 class ConvertableToTraceFormat;
  16 class TracedValue;
  17 }
  18 }
  19
  20 namespace cc {
  21
  22 struct CC_EXPORT BeginFrameArgs {
  23   // Creates an invalid set of values.
  24   BeginFrameArgs();
  25
  26   // You should be able to find all instances where a BeginFrame has been
  27   // created by searching for "BeginFrameArgs::Create".
  28   static BeginFrameArgs Create(base::TimeTicks frame_time,
  29                                base::TimeTicks deadline,
  30                                base::TimeDelta interval);
  31   static BeginFrameArgs CreateForSynchronousCompositor(
  32       base::TimeTicks now = base::TimeTicks());
  33
  34   // This is the default delta that will be used to adjust the deadline when
  35   // proper draw-time estimations are not yet available.
  36   static base::TimeDelta DefaultEstimatedParentDrawTime();
  37
  38   // This is the default interval to use to avoid sprinkling the code with
  39   // magic numbers.
  40   static base::TimeDelta DefaultInterval();
  41
  42   // This is the default amount of time after the frame_time to retroactively
  43   // send a BeginFrame that had been skipped. This only has an effect if the
  44   // deadline has passed, since the deadline is also used to trigger BeginFrame
  45   // retroactively.
  46   static base::TimeDelta DefaultRetroactiveBeginFramePeriod();
  47
  48   bool IsValid() const { return interval >= base::TimeDelta(); }
  49
  50   scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;
  51   void AsValueInto(base::debug::TracedValue* dict) const;
  52
  53   base::TimeTicks frame_time;
  54   base::TimeTicks deadline;
  55   base::TimeDelta interval;
  56
  57  private:
  58   BeginFrameArgs(base::TimeTicks frame_time,
  59                  base::TimeTicks deadline,
  60                  base::TimeDelta interval);
  61 };
  62
  63 }  // namespace cc
  64
  65 #endif  // CC_OUTPUT_BEGIN_FRAME_ARGS_H_