root/Source/core/animation/TimedItem.h

INCLUDED FROM

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#ifndef TimedItem_h
#define TimedItem_h

#include "core/animation/Timing.h"
#include "wtf/OwnPtr.h"
#include "wtf/PassOwnPtr.h"
#include "wtf/RefCounted.h"

namespace WebCore {

class AnimationPlayer;
class TimedItem;
class TimedItemTiming;

static inline bool isNull(double value)
{
    return std::isnan(value);
}

static inline double nullValue()
{
    return std::numeric_limits<double>::quiet_NaN();
}

class TimedItem : public RefCounted<TimedItem> {
    friend class AnimationPlayer; // Calls attach/detach, updateInheritedTime.
public:
    // Note that logic in CSSAnimations depends on the order of these values.
    enum Phase {
        PhaseBefore,
        PhaseActive,
        PhaseAfter,
        PhaseNone,
    };

    class EventDelegate {
    public:
        virtual ~EventDelegate() { };
        virtual void onEventCondition(const TimedItem*, bool isFirstSample, Phase previousPhase, double previousIteration) = 0;
    };

    virtual ~TimedItem() { }

    virtual bool isAnimation() const { return false; }

    Phase phase() const { return ensureCalculated().phase; }
    bool isCurrent() const { return ensureCalculated().isCurrent; }
    bool isInEffect() const { return ensureCalculated().isInEffect; }
    bool isInPlay() const { return ensureCalculated().isInPlay; }
    double timeToForwardsEffectChange() const { return ensureCalculated().timeToForwardsEffectChange; }
    double timeToReverseEffectChange() const { return ensureCalculated().timeToReverseEffectChange; }

    double currentIteration() const { return ensureCalculated().currentIteration; }
    double duration() const { return iterationDuration(); }
    double activeDuration() const;
    double timeFraction() const { return ensureCalculated().timeFraction; }
    double startTime() const { return m_startTime; }
    double endTime() const { return startTime() + specifiedTiming().startDelay + activeDuration() + specifiedTiming().endDelay; }

    const AnimationPlayer* player() const { return m_player; }
    AnimationPlayer* player() { return m_player; }
    AnimationPlayer* player(bool& isNull) { isNull = !m_player; return m_player; }
    const Timing& specifiedTiming() const { return m_specified; }
    PassRefPtr<TimedItemTiming> specified();
    void updateSpecifiedTiming(const Timing&);

    double localTime(bool& isNull) const { isNull = !m_player; return ensureCalculated().localTime; }
    double currentIteration(bool& isNull) const { isNull = !ensureCalculated().isInEffect; return ensureCalculated().currentIteration; }

protected:
    TimedItem(const Timing&, PassOwnPtr<EventDelegate> = nullptr);

    // When TimedItem receives a new inherited time via updateInheritedTime
    // it will (if necessary) recalculate timings and (if necessary) call
    // updateChildrenAndEffects.
    void updateInheritedTime(double inheritedTime) const;
    void invalidate() const { m_needsUpdate = true; };

private:

    double iterationDuration() const;
    double repeatedDuration() const;

    virtual void updateChildrenAndEffects() const = 0;
    virtual double intrinsicIterationDuration() const { return 0; };
    virtual double calculateTimeToEffectChange(bool forwards, double localTime, double timeToNextIteration) const = 0;
    virtual void didAttach() { };
    virtual void willDetach() { };

    void attach(AnimationPlayer* player)
    {
        m_player = player;
        didAttach();
    };

    void detach()
    {
        ASSERT(m_player);
        willDetach();
        m_player = 0;
    };

    // FIXME: m_parent and m_startTime are placeholders, they depend on timing groups.
    TimedItem* const m_parent;
    const double m_startTime;
    AnimationPlayer* m_player;
    Timing m_specified;
    OwnPtr<EventDelegate> m_eventDelegate;

    mutable struct CalculatedTiming {
        Phase phase;
        double currentIteration;
        double timeFraction;
        bool isCurrent;
        bool isInEffect;
        bool isInPlay;
        double localTime;
        double timeToForwardsEffectChange;
        double timeToReverseEffectChange;
    } m_calculated;
    mutable bool m_isFirstSample;
    mutable bool m_needsUpdate;
    mutable double m_lastUpdateTime;

    const CalculatedTiming& ensureCalculated() const;
};

} // namespace WebCore

#endif