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32 #include "core/animation/AnimationClock.h"
34 #include "wtf/CurrentTime.h"
39 // FIXME: This is an approximation of time between frames, used when
40 // ticking the animation clock outside of animation frame callbacks.
41 // Ideally this would be generated by the compositor.
42 const double approximateFrameTime = 1 / 60.0;
48 unsigned AnimationClock::s_currentTask = 0;
50 void AnimationClock::updateTime(double time)
54 m_currentTask = s_currentTask;
57 double AnimationClock::currentTime()
59 if (m_currentTask != s_currentTask) {
60 const double currentTime = m_monotonicallyIncreasingTime();
61 if (m_time < currentTime) {
62 // Advance to the first estimated frame after the current time.
63 const double frameShift = fmod(currentTime - m_time, approximateFrameTime);
64 const double newTime = currentTime + (approximateFrameTime - frameShift);
65 ASSERT(newTime >= currentTime);
66 ASSERT(newTime <= currentTime + approximateFrameTime);
69 m_currentTask = s_currentTask;
75 void AnimationClock::resetTimeForTesting()