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31 #ifndef TimedItemCalculations_h
32 #define TimedItemCalculations_h
34 #include "core/animation/TimedItem.h"
35 #include "core/animation/Timing.h"
36 #include "platform/animation/AnimationUtilities.h"
37 #include "wtf/MathExtras.h"
41 static inline double multiplyZeroAlwaysGivesZero(double x, double y)
45 return x && y ? x * y : 0;
48 static inline TimedItem::Phase calculatePhase(double activeDuration, double localTime, const Timing& specified)
50 ASSERT(activeDuration >= 0);
51 if (isNull(localTime))
52 return TimedItem::PhaseNone;
53 if (localTime < specified.startDelay)
54 return TimedItem::PhaseBefore;
55 if (localTime >= specified.startDelay + activeDuration)
56 return TimedItem::PhaseAfter;
57 return TimedItem::PhaseActive;
60 static inline bool isActiveInParentPhase(TimedItem::Phase parentPhase, Timing::FillMode fillMode)
62 switch (parentPhase) {
63 case TimedItem::PhaseBefore:
64 return fillMode == Timing::FillModeBackwards || fillMode == Timing::FillModeBoth;
65 case TimedItem::PhaseActive:
67 case TimedItem::PhaseAfter:
68 return fillMode == Timing::FillModeForwards || fillMode == Timing::FillModeBoth;
75 static inline double calculateActiveTime(double activeDuration, Timing::FillMode fillMode, double localTime, TimedItem::Phase parentPhase, TimedItem::Phase phase, const Timing& specified)
77 ASSERT(activeDuration >= 0);
78 ASSERT(phase == calculatePhase(activeDuration, localTime, specified));
81 case TimedItem::PhaseBefore:
82 if (fillMode == Timing::FillModeBackwards || fillMode == Timing::FillModeBoth)
85 case TimedItem::PhaseActive:
86 if (isActiveInParentPhase(parentPhase, fillMode))
87 return localTime - specified.startDelay;
89 case TimedItem::PhaseAfter:
90 if (fillMode == Timing::FillModeForwards || fillMode == Timing::FillModeBoth)
91 return activeDuration;
93 case TimedItem::PhaseNone:
94 ASSERT(isNull(localTime));
102 static inline double calculateScaledActiveTime(double activeDuration, double activeTime, double startOffset, const Timing& specified)
104 ASSERT(activeDuration >= 0);
105 ASSERT(startOffset >= 0);
107 if (isNull(activeTime))
110 ASSERT(activeTime >= 0 && activeTime <= activeDuration);
111 return multiplyZeroAlwaysGivesZero(specified.playbackRate < 0 ? activeTime - activeDuration : activeTime, specified.playbackRate) + startOffset;
114 static inline bool endsOnIterationBoundary(double iterationCount, double iterationStart)
116 ASSERT(std::isfinite(iterationCount));
117 return !fmod(iterationCount + iterationStart, 1);
120 static inline double calculateIterationTime(double iterationDuration, double repeatedDuration, double scaledActiveTime, double startOffset, const Timing& specified)
122 ASSERT(iterationDuration > 0);
123 ASSERT(repeatedDuration == multiplyZeroAlwaysGivesZero(iterationDuration, specified.iterationCount));
125 if (isNull(scaledActiveTime))
128 ASSERT(scaledActiveTime >= 0);
129 ASSERT(scaledActiveTime <= repeatedDuration + startOffset);
131 if (!std::isfinite(scaledActiveTime)
132 || (scaledActiveTime - startOffset == repeatedDuration && specified.iterationCount && endsOnIterationBoundary(specified.iterationCount, specified.iterationStart)))
133 return iterationDuration;
135 ASSERT(std::isfinite(scaledActiveTime));
136 return fmod(scaledActiveTime, iterationDuration);
139 static inline double calculateCurrentIteration(double iterationDuration, double iterationTime, double scaledActiveTime, const Timing& specified)
141 ASSERT(iterationDuration > 0);
142 ASSERT(isNull(iterationTime) || iterationTime >= 0);
144 if (isNull(scaledActiveTime))
147 ASSERT(iterationTime >= 0);
148 ASSERT(iterationTime <= iterationDuration);
149 ASSERT(scaledActiveTime >= 0);
151 if (!scaledActiveTime)
154 if (iterationTime == iterationDuration)
155 return specified.iterationStart + specified.iterationCount - 1;
157 return floor(scaledActiveTime / iterationDuration);
160 static inline double calculateDirectedTime(double currentIteration, double iterationDuration, double iterationTime, const Timing& specified)
162 ASSERT(isNull(currentIteration) || currentIteration >= 0);
163 ASSERT(iterationDuration > 0);
165 if (isNull(iterationTime))
168 ASSERT(currentIteration >= 0);
169 ASSERT(iterationTime >= 0);
170 ASSERT(iterationTime <= iterationDuration);
172 const bool currentIterationIsOdd = fmod(currentIteration, 2) >= 1;
173 const bool currentDirectionIsForwards = specified.direction == Timing::PlaybackDirectionNormal
174 || (specified.direction == Timing::PlaybackDirectionAlternate && !currentIterationIsOdd)
175 || (specified.direction == Timing::PlaybackDirectionAlternateReverse && currentIterationIsOdd);
177 return currentDirectionIsForwards ? iterationTime : iterationDuration - iterationTime;
180 static inline double calculateTransformedTime(double currentIteration, double iterationDuration, double iterationTime, const Timing& specified)
182 ASSERT(isNull(currentIteration) || currentIteration >= 0);
183 ASSERT(iterationDuration > 0);
184 ASSERT(isNull(iterationTime) || (iterationTime >= 0 && iterationTime <= iterationDuration));
186 double directedTime = calculateDirectedTime(currentIteration, iterationDuration, iterationTime, specified);
187 if (isNull(directedTime))
189 if (!std::isfinite(iterationDuration))
191 double timeFraction = directedTime / iterationDuration;
192 ASSERT(timeFraction >= 0 && timeFraction <= 1);
193 return specified.timingFunction
194 ? multiplyZeroAlwaysGivesZero(iterationDuration, specified.timingFunction->evaluate(timeFraction, accuracyForDuration(iterationDuration)))
198 } // namespace WebCore