Source/core/animation/Player.h

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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#ifndef Player_h
#define Player_h

#include "core/animation/TimedItem.h"
#include "wtf/RefPtr.h"

namespace WebCore {

class DocumentTimeline;

class Player FINAL : public RefCounted<Player> {

public:
    ~Player();
    static PassRefPtr<Player> create(DocumentTimeline&, TimedItem*);

    // Returns whether this player is still current or in effect.
    // timeToEffectChange returns:
    //  infinity  - if this player is no longer in effect
    //  0         - if this player requires an update on the next frame
    //  n         - if this player requires an update after 'n' units of time
    bool update(double* timeToEffectChange = 0, bool* didTriggerStyleRecalc = 0);
    void cancel();

    double currentTime() const;
    void setCurrentTime(double);

    bool paused() const { return !m_isPausedForTesting && pausedInternal(); }
    void setPaused(bool);

    double playbackRate() const { return m_playbackRate; }
    void setPlaybackRate(double);
    double timeDrift() const;
    DocumentTimeline& timeline() { return m_timeline; }

    bool hasStartTime() const { return !isNull(m_startTime); }
    double startTime() const { return m_startTime; }
    void setStartTime(double);

    TimedItem* source() { return m_content.get(); }

    // Pausing via this method is not reflected in the value returned by
    // paused() and must never overlap with pausing via setPaused().
    void pauseForTesting();
    // Reflects all pausing, including via pauseForTesting().
    bool pausedInternal() const { return !isNull(m_pauseStartTime); }

    bool maybeStartAnimationOnCompositor();
    void cancelAnimationOnCompositor();
    bool hasActiveAnimationsOnCompositor();

private:
    Player(DocumentTimeline&, TimedItem*);
    inline double pausedTimeDrift() const;
    inline double currentTimeBeforeDrift() const;


    void setPausedImpl(bool);

    double m_pauseStartTime;
    double m_playbackRate;
    double m_timeDrift;
    double m_startTime;
    double m_lastUpdateTime;

    RefPtr<TimedItem> m_content;
    DocumentTimeline& m_timeline;
    bool m_isPausedForTesting;
};

} // namespace

#endif