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 if (TimestampsAreHighRes()) 19 return base::TimeTicks::HighResNow(); 20 return base::TimeTicks::Now(); 21 } 22 23 #if defined(OS_WIN) 24 static base::TimeTicks FromQPCValue(LONGLONG qpc_value) { 25 DCHECK(TimestampsAreHighRes()); 26 return base::TimeTicks::FromQPCValue(qpc_value); 27 } 28 #endif 29 30 static bool TimestampsAreHighRes() { 31 // This should really return base::TimeTicks::IsHighResNowFastAndReliable(); 32 // Returning false makes sure we are only using low-res timestamps until we 33 // use FrameTime everywhere we need to. See crbug.com/315334 34 return false; 35 } 36 }; 37 38 } 39 40 #endif // UI_GFX_FRAME_TIME_H 41
