Source/core/animation/TimedItem.cpp

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#include "config.h"
#include "core/animation/TimedItem.h"
#include "core/animation/TimedItemCalculations.h"

namespace WebCore {

TimedItem::TimedItem(const Timing& timing, PassOwnPtr<EventDelegate> eventDelegate)
    : m_parent(0)
    , m_startTime(0)
    , m_player(0)
    , m_specified(timing)
    , m_eventDelegate(eventDelegate)
    , m_calculated()
    , m_isFirstSample(true)
{
    timing.assertValid();
}

bool TimedItem::updateInheritedTime(double inheritedTime) const
{
    const double localTime = inheritedTime - m_startTime;
    const double iterationDuration = m_specified.hasIterationDuration
        ? m_specified.iterationDuration
        : intrinsicIterationDuration();

    const double repeatedDuration = iterationDuration * m_specified.iterationCount;
    const double activeDuration = m_specified.playbackRate
        ? repeatedDuration / abs(m_specified.playbackRate)
        : std::numeric_limits<double>::infinity();

    const Phase currentPhase = calculatePhase(activeDuration, localTime, m_specified);
    // FIXME: parentPhase depends on groups being implemented.
    const TimedItem::Phase parentPhase = TimedItem::PhaseActive;
    const double activeTime = calculateActiveTime(activeDuration, localTime, parentPhase, currentPhase, m_specified);

    double currentIteration = nullValue();
    double timeFraction = nullValue();
    ASSERT(iterationDuration >= 0);
    if (iterationDuration) {
        const double startOffset = m_specified.iterationStart * iterationDuration;
        const double scaledActiveTime = calculateScaledActiveTime(activeDuration, activeTime, startOffset, m_specified);
        const double iterationTime = calculateIterationTime(iterationDuration, repeatedDuration, scaledActiveTime, startOffset, m_specified);

        currentIteration = calculateCurrentIteration(iterationDuration, iterationTime, scaledActiveTime, m_specified);
        timeFraction = calculateTransformedTime(currentIteration, iterationDuration, iterationTime, m_specified) / iterationDuration;
    } else {
        const double iterationDuration = 1;
        const double repeatedDuration = iterationDuration * m_specified.iterationCount;
        const double activeDuration = m_specified.playbackRate ? repeatedDuration / abs(m_specified.playbackRate) : std::numeric_limits<double>::infinity();
        const double newLocalTime = localTime < m_specified.startDelay ? m_specified.startDelay - 1 : activeDuration + m_specified.startDelay;
        const TimedItem::Phase localPhase = calculatePhase(activeDuration, newLocalTime, m_specified);
        const double activeTime = calculateActiveTime(activeDuration, newLocalTime, parentPhase, localPhase, m_specified);
        const double startOffset = m_specified.iterationStart * iterationDuration;
        const double scaledActiveTime = calculateScaledActiveTime(activeDuration, activeTime, startOffset, m_specified);
        const double iterationTime = calculateIterationTime(iterationDuration, repeatedDuration, scaledActiveTime, startOffset, m_specified);

        currentIteration = calculateCurrentIteration(iterationDuration, iterationTime, scaledActiveTime, m_specified);
        timeFraction = calculateTransformedTime(currentIteration, iterationDuration, iterationTime, m_specified);
    }

    const double previousIteration = m_calculated.currentIteration;
    m_calculated.currentIteration = currentIteration;
    m_calculated.activeDuration = activeDuration;
    m_calculated.timeFraction = timeFraction;

    const Phase previousPhase = m_calculated.phase;
    m_calculated.phase = currentPhase;
    m_calculated.isInEffect = !isNull(activeTime);
    m_calculated.isInPlay = phase() == PhaseActive && (!m_parent || m_parent->isInPlay());
    m_calculated.isCurrent = phase() == PhaseBefore || isInPlay() || (m_parent && m_parent->isCurrent());

    // This logic is specific to CSS animation events and assumes that all
    // animations start after the DocumentTimeline has started.
    if (m_eventDelegate && (m_isFirstSample || previousPhase != phase() || (phase() == PhaseActive && previousIteration != currentIteration)))
        m_eventDelegate->onEventCondition(this, m_isFirstSample, previousPhase, previousIteration);
    m_isFirstSample = false;

    // FIXME: This probably shouldn't be recursive.
    bool didTriggerStyleRecalc = updateChildrenAndEffects();

    m_calculated.timeToEffectChange = calculateTimeToEffectChange(localTime, m_startTime + m_specified.startDelay, m_calculated.phase);
    return didTriggerStyleRecalc;
}

} // namespace WebCore