ui/gfx/frame_time.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 UI_GFX_FRAME_TIME_H
   6 #define UI_GFX_FRAME_TIME_H
   7
   8 #include "base/time/time.h"
   9 #include "base/logging.h"
  10
  11 namespace gfx {
  12
  13 // FrameTime::Now() should be used to get timestamps with a timebase that
  14 // is consistent across the graphics stack.
  15 class FrameTime {
  16  public:
  17   static base::TimeTicks Now() {
  18     return base::TimeTicks::Now();
  19   }
  20
  21 #if defined(OS_WIN)
  22   static base::TimeTicks FromQPCValue(LONGLONG qpc_value) {
  23     DCHECK(TimestampsAreHighRes());
  24     return base::TimeTicks::FromQPCValue(qpc_value);
  25   }
  26 #endif
  27
  28   static bool TimestampsAreHighRes() {
  29 #if defined(OS_WIN)
  30     return base::TimeTicks::IsHighResolution();
  31 #else
  32     // TODO(miu): Mac/Linux always provide high-resolution timestamps.  Consider
  33     // returning base::TimeTicks::IsHighResolution() for all platforms.
  34     return false;
  35 #endif
  36   }
  37 };
  38
  39 }
  40
  41 #endif // UI_GFX_FRAME_TIME_H