qtimeline.cpp

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#include "qtimeline.h"

#include <private/qobject_p.h>
#include <QtCore/qcoreevent.h>
#include <QtCore/qmath.h>
#include <QtCore/qelapsedtimer.h>

QT_BEGIN_NAMESPACE

class QTimeLinePrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QTimeLine)
public:
    inline QTimeLinePrivate()
        : startTime(0), duration(1000), startFrame(0), endFrame(0),
          updateInterval(1000 / 25),
          totalLoopCount(1), currentLoopCount(0), currentTime(0), timerId(0),
          direction(QTimeLine::Forward), easingCurve(QEasingCurve::InOutSine),
          state(QTimeLine::NotRunning)
    { }

    int startTime;
    int duration;
    int startFrame;
    int endFrame;
    int updateInterval;
    int totalLoopCount;
    int currentLoopCount;

    int currentTime;
    int timerId;
    QElapsedTimer timer;

    QTimeLine::Direction direction;
    QEasingCurve easingCurve;
    QTimeLine::State state;
    inline void setState(QTimeLine::State newState)
    {
        Q_Q(QTimeLine);
        if (newState != state)
            emit q->stateChanged(state = newState);
    }

    void setCurrentTime(int msecs);
};

void QTimeLinePrivate::setCurrentTime(int msecs)
{
    Q_Q(QTimeLine);

    qreal lastValue = q->currentValue();
    int lastFrame = q->currentFrame();

    // Determine if we are looping.
    int elapsed = (direction == QTimeLine::Backward) ? (-msecs +  duration) : msecs;
    int loopCount = elapsed / duration;

    bool looping = (loopCount != currentLoopCount);
#ifdef QTIMELINE_DEBUG
    qDebug() << "QTimeLinePrivate::setCurrentTime:" << msecs << duration << "with loopCount" << loopCount
             << "currentLoopCount" << currentLoopCount
             << "looping" << looping;
#endif
    if (looping)
        currentLoopCount = loopCount;

    // Normalize msecs to be between 0 and duration, inclusive.
    currentTime = elapsed % duration;
    if (direction == QTimeLine::Backward)
        currentTime = duration - currentTime;

    // Check if we have reached the end of loopcount.
    bool finished = false;
    if (totalLoopCount && currentLoopCount >= totalLoopCount) {
        finished = true;
        currentTime = (direction == QTimeLine::Backward) ? 0 : duration;
        currentLoopCount = totalLoopCount - 1;
    }

    int currentFrame = q->frameForTime(currentTime);
#ifdef QTIMELINE_DEBUG
    qDebug() << "QTimeLinePrivate::setCurrentTime: frameForTime" << currentTime << currentFrame;
#endif
    if (!qFuzzyCompare(lastValue, q->currentValue()))
        emit q->valueChanged(q->currentValue());
    if (lastFrame != currentFrame) {
        const int transitionframe = (direction == QTimeLine::Forward ? endFrame : startFrame);
        if (looping && !finished && transitionframe != currentFrame) {
#ifdef QTIMELINE_DEBUG
            qDebug() << "QTimeLinePrivate::setCurrentTime: transitionframe";
#endif
            emit q->frameChanged(transitionframe);
        }
#ifdef QTIMELINE_DEBUG
        else {
            QByteArray reason;
            if (!looping)
                reason += " not looping";
            if (finished) {
                if (!reason.isEmpty())
                    reason += " and";
                reason += " finished";
            }
            if (transitionframe == currentFrame) {
                if (!reason.isEmpty())
                    reason += " and";
                reason += " transitionframe is equal to currentFrame: " + QByteArray::number(currentFrame);
            }
            qDebug("QTimeLinePrivate::setCurrentTime: not transitionframe because %s",  reason.constData());
        }
#endif
        emit q->frameChanged(currentFrame);
    }
    if (finished && state == QTimeLine::Running) {
        q->stop();
        emit q->finished();
    }
}

QTimeLine::QTimeLine(int duration, QObject *parent)
    : QObject(*new QTimeLinePrivate, parent)
{
    setDuration(duration);
}

QTimeLine::~QTimeLine()
{
    Q_D(QTimeLine);

    if (d->state == Running)
        stop();
}

QTimeLine::State QTimeLine::state() const
{
    Q_D(const QTimeLine);
    return d->state;
}

int QTimeLine::loopCount() const
{
    Q_D(const QTimeLine);
    return d->totalLoopCount;
}
void QTimeLine::setLoopCount(int count)
{
    Q_D(QTimeLine);
    d->totalLoopCount = count;
}

QTimeLine::Direction QTimeLine::direction() const
{
    Q_D(const QTimeLine);
    return d->direction;
}
void QTimeLine::setDirection(Direction direction)
{
    Q_D(QTimeLine);
    d->direction = direction;
    d->startTime = d->currentTime;
    d->timer.start();
}

int QTimeLine::duration() const
{
    Q_D(const QTimeLine);
    return d->duration;
}
void QTimeLine::setDuration(int duration)
{
    Q_D(QTimeLine);
    if (duration <= 0) {
        qWarning("QTimeLine::setDuration: cannot set duration <= 0");
        return;
    }
    d->duration = duration;
}

int QTimeLine::startFrame() const
{
    Q_D(const QTimeLine);
    return d->startFrame;
}

void QTimeLine::setStartFrame(int frame)
{
    Q_D(QTimeLine);
    d->startFrame = frame;
}

int QTimeLine::endFrame() const
{
    Q_D(const QTimeLine);
    return d->endFrame;
}

void QTimeLine::setEndFrame(int frame)
{
    Q_D(QTimeLine);
    d->endFrame = frame;
}

void QTimeLine::setFrameRange(int startFrame, int endFrame)
{
    Q_D(QTimeLine);
    d->startFrame = startFrame;
    d->endFrame = endFrame;
}

int QTimeLine::updateInterval() const
{
    Q_D(const QTimeLine);
    return d->updateInterval;
}
void QTimeLine::setUpdateInterval(int interval)
{
    Q_D(QTimeLine);
    d->updateInterval = interval;
}

QTimeLine::CurveShape QTimeLine::curveShape() const
{
    Q_D(const QTimeLine);
    switch (d->easingCurve.type()) {
    default:
    case QEasingCurve::InOutSine:
        return EaseInOutCurve;
    case QEasingCurve::InCurve:
        return EaseInCurve;
    case QEasingCurve::OutCurve:
        return EaseOutCurve;
    case QEasingCurve::Linear:
        return LinearCurve;
    case QEasingCurve::SineCurve:
        return SineCurve;
    case QEasingCurve::CosineCurve:
        return CosineCurve;
    }
    return EaseInOutCurve;
}

void QTimeLine::setCurveShape(CurveShape shape)
{
    switch (shape) {
    default:
    case EaseInOutCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::InOutSine));
        break;
    case EaseInCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::InCurve));
        break;
    case EaseOutCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::OutCurve));
        break;
    case LinearCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::Linear));
        break;
    case SineCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::SineCurve));
        break;
    case CosineCurve:
        setEasingCurve(QEasingCurve(QEasingCurve::CosineCurve));
        break;
    }
}

QEasingCurve QTimeLine::easingCurve() const
{
    Q_D(const QTimeLine);
    return d->easingCurve;
}

void QTimeLine::setEasingCurve(const QEasingCurve& curve)
{
    Q_D(QTimeLine);
    d->easingCurve = curve;
}

int QTimeLine::currentTime() const
{
    Q_D(const QTimeLine);
    return d->currentTime;
}
void QTimeLine::setCurrentTime(int msec)
{
    Q_D(QTimeLine);
    d->startTime = 0;
    d->currentLoopCount = 0;
    d->timer.restart();
    d->setCurrentTime(msec);
}

int QTimeLine::currentFrame() const
{
    Q_D(const QTimeLine);
    return frameForTime(d->currentTime);
}

qreal QTimeLine::currentValue() const
{
    Q_D(const QTimeLine);
    return valueForTime(d->currentTime);
}

int QTimeLine::frameForTime(int msec) const
{
    Q_D(const QTimeLine);
    if (d->direction == Forward)
        return d->startFrame + int((d->endFrame - d->startFrame) * valueForTime(msec));
    return d->startFrame + qCeil((d->endFrame - d->startFrame) * valueForTime(msec));
}

qreal QTimeLine::valueForTime(int msec) const
{
    Q_D(const QTimeLine);
    msec = qMin(qMax(msec, 0), d->duration);

    qreal value = msec / qreal(d->duration);
    return d->easingCurve.valueForProgress(value);
}

void QTimeLine::start()
{
    Q_D(QTimeLine);
    if (d->timerId) {
        qWarning("QTimeLine::start: already running");
        return;
    }
    int curTime = 0;
    if (d->direction == Backward)
        curTime = d->duration;
    d->timerId = startTimer(d->updateInterval);
    d->startTime = curTime;
    d->currentLoopCount = 0;
    d->timer.start();
    d->setState(Running);
    d->setCurrentTime(curTime);
}

void QTimeLine::resume()
{
    Q_D(QTimeLine);
    if (d->timerId) {
        qWarning("QTimeLine::resume: already running");
        return;
    }
    d->timerId = startTimer(d->updateInterval);
    d->startTime = d->currentTime;
    d->timer.start();
    d->setState(Running);
}

void QTimeLine::stop()
{
    Q_D(QTimeLine);
    if (d->timerId)
        killTimer(d->timerId);
    d->setState(NotRunning);
    d->timerId = 0;
}

void QTimeLine::setPaused(bool paused)
{
    Q_D(QTimeLine);
    if (d->state == NotRunning) {
        qWarning("QTimeLine::setPaused: Not running");
        return;
    }
    if (paused && d->state != Paused) {
        d->startTime = d->currentTime;
        killTimer(d->timerId);
        d->timerId = 0;
        d->setState(Paused);
    } else if (!paused && d->state == Paused) {
        // Same as resume()
        d->timerId = startTimer(d->updateInterval);
        d->startTime = d->currentTime;
        d->timer.start();
        d->setState(Running);
    }
}

void QTimeLine::toggleDirection()
{
    Q_D(QTimeLine);
    setDirection(d->direction == Forward ? Backward : Forward);
}

void QTimeLine::timerEvent(QTimerEvent *event)
{
    Q_D(QTimeLine);
    if (event->timerId() != d->timerId) {
        event->ignore();
        return;
    }
    event->accept();

    if (d->direction == Forward) {
        d->setCurrentTime(d->startTime + d->timer.elapsed());
    } else {
        d->setCurrentTime(d->startTime - d->timer.elapsed());
    }
}

QT_END_NAMESPACE