qabstractanimation.cpp

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#include "qabstractanimation.h"
#include "qanimationgroup.h"

#include <QtCore/qdebug.h>

#include "qabstractanimation_p.h"

#include <QtCore/qmath.h>
#include <QtCore/qthreadstorage.h>
#include <QtCore/qcoreevent.h>
#include <QtCore/qpointer.h>

#ifndef QT_NO_ANIMATION

#define DEFAULT_TIMER_INTERVAL 16
#define STARTSTOP_TIMER_DELAY 0

QT_BEGIN_NAMESPACE

#ifndef QT_NO_THREAD
Q_GLOBAL_STATIC(QThreadStorage<QUnifiedTimer *>, unifiedTimer)
#endif

QUnifiedTimer::QUnifiedTimer() :
    QObject(), defaultDriver(this), lastTick(0), timingInterval(DEFAULT_TIMER_INTERVAL),
    currentAnimationIdx(0), insideTick(false), consistentTiming(false), slowMode(false),
    slowdownFactor(5.0f), isPauseTimerActive(false), runningLeafAnimations(0)
{
    time.invalidate();
    driver = &defaultDriver;
}


QUnifiedTimer *QUnifiedTimer::instance(bool create)
{
    QUnifiedTimer *inst;
#ifndef QT_NO_THREAD
    if (create && !unifiedTimer()->hasLocalData()) {
        inst = new QUnifiedTimer;
        unifiedTimer()->setLocalData(inst);
    } else {
        inst = unifiedTimer()->localData();
    }
#else
    static QUnifiedTimer unifiedTimer;
    inst = &unifiedTimer;
#endif
    return inst;
}

QUnifiedTimer *QUnifiedTimer::instance()
{
    return instance(true);
}

void QUnifiedTimer::ensureTimerUpdate()
{
    QUnifiedTimer *inst = QUnifiedTimer::instance(false);
    if (inst && inst->isPauseTimerActive)
        inst->updateAnimationsTime();
}

void QUnifiedTimer::updateAnimationsTime()
{
    //setCurrentTime can get this called again while we're the for loop. At least with pauseAnimations
    if(insideTick)
        return;

    qint64 totalElapsed = time.elapsed();
    // ignore consistentTiming in case the pause timer is active
    int delta = (consistentTiming && !isPauseTimerActive) ?
                        timingInterval : totalElapsed - lastTick;
    if (slowMode) {
        if (slowdownFactor > 0)
            delta = qRound(delta / slowdownFactor);
        else
            delta = 0;
    }

    lastTick = totalElapsed;

    //we make sure we only call update time if the time has actually changed
    //it might happen in some cases that the time doesn't change because events are delayed
    //when the CPU load is high
    if (delta) {
        insideTick = true;
        for (currentAnimationIdx = 0; currentAnimationIdx < animations.count(); ++currentAnimationIdx) {
            QAbstractAnimation *animation = animations.at(currentAnimationIdx);
            int elapsed = QAbstractAnimationPrivate::get(animation)->totalCurrentTime
                          + (animation->direction() == QAbstractAnimation::Forward ? delta : -delta);
            animation->setCurrentTime(elapsed);
        }
        insideTick = false;
        currentAnimationIdx = 0;
    }
}

void QUnifiedTimer::updateAnimationTimer()
{
    QUnifiedTimer *inst = QUnifiedTimer::instance(false);
    if (inst)
        inst->restartAnimationTimer();
}

void QUnifiedTimer::restartAnimationTimer()
{
    if (runningLeafAnimations == 0 && !runningPauseAnimations.isEmpty()) {
        int closestTimeToFinish = closestPauseAnimationTimeToFinish();
        if (closestTimeToFinish < 0) {
            qDebug() << runningPauseAnimations;
            qDebug() << closestPauseAnimationTimeToFinish();
        }
        driver->stop();
        animationTimer.start(closestTimeToFinish, this);
        isPauseTimerActive = true;
    } else if (!driver->isRunning() || isPauseTimerActive) {
        driver->start();
        isPauseTimerActive = false;
    } else if (runningLeafAnimations == 0)
        driver->stop();
}

void QUnifiedTimer::setTimingInterval(int interval)
{
    timingInterval = interval;

    if (driver->isRunning() && !isPauseTimerActive) {
        //we changed the timing interval
        driver->stop();
        driver->start();
    }
}


void QUnifiedTimer::timerEvent(QTimerEvent *event)
{
    //in the case of consistent timing we make sure the orders in which events come is always the same
   //for that purpose we do as if the startstoptimer would always fire before the animation timer
    if ((consistentTiming && startStopAnimationTimer.isActive()) ||
        event->timerId() == startStopAnimationTimer.timerId()) {
        startStopAnimationTimer.stop();

        //we transfer the waiting animations into the "really running" state
        animations += animationsToStart;
        animationsToStart.clear();
        if (animations.isEmpty()) {
            animationTimer.stop();
            isPauseTimerActive = false;
            // invalidate the start reference time
            time.invalidate();
        } else {
            restartAnimationTimer();
            if (!time.isValid()) {
                lastTick = 0;
                time.start();
            }
        }
    }

    if (event->timerId() == animationTimer.timerId()) {
        // update current time on all top level animations
        updateAnimationsTime();
        restartAnimationTimer();
    }
}

void QUnifiedTimer::registerAnimation(QAbstractAnimation *animation, bool isTopLevel)
{
    QUnifiedTimer *inst = instance(true); //we create the instance if needed
    inst->registerRunningAnimation(animation);
    if (isTopLevel) {
        Q_ASSERT(!QAbstractAnimationPrivate::get(animation)->hasRegisteredTimer);
        QAbstractAnimationPrivate::get(animation)->hasRegisteredTimer = true;
        inst->animationsToStart << animation;
        if (!inst->startStopAnimationTimer.isActive())
            inst->startStopAnimationTimer.start(STARTSTOP_TIMER_DELAY, inst);
    }
}

void QUnifiedTimer::unregisterAnimation(QAbstractAnimation *animation)
{
    QUnifiedTimer *inst = QUnifiedTimer::instance(false);
    if (inst) {
        //at this point the unified timer should have been created
        //but it might also have been already destroyed in case the application is shutting down

        inst->unregisterRunningAnimation(animation);

        if (!QAbstractAnimationPrivate::get(animation)->hasRegisteredTimer)
            return;

        int idx = inst->animations.indexOf(animation);
        if (idx != -1) {
            inst->animations.removeAt(idx);
            // this is needed if we unregister an animation while its running
            if (idx <= inst->currentAnimationIdx)
                --inst->currentAnimationIdx;

            if (inst->animations.isEmpty() && !inst->startStopAnimationTimer.isActive())
                inst->startStopAnimationTimer.start(STARTSTOP_TIMER_DELAY, inst);
        } else {
            inst->animationsToStart.removeOne(animation);
        }
    }
    QAbstractAnimationPrivate::get(animation)->hasRegisteredTimer = false;
}

void QUnifiedTimer::registerRunningAnimation(QAbstractAnimation *animation)
{
    if (QAbstractAnimationPrivate::get(animation)->isGroup)
        return;

    if (QAbstractAnimationPrivate::get(animation)->isPause) {
        runningPauseAnimations << animation;
    } else
        runningLeafAnimations++;
}

void QUnifiedTimer::unregisterRunningAnimation(QAbstractAnimation *animation)
{
    if (QAbstractAnimationPrivate::get(animation)->isGroup)
        return;

    if (QAbstractAnimationPrivate::get(animation)->isPause)
        runningPauseAnimations.removeOne(animation);
    else
        runningLeafAnimations--;
    Q_ASSERT(runningLeafAnimations >= 0);
}

int QUnifiedTimer::closestPauseAnimationTimeToFinish()
{
    int closestTimeToFinish = INT_MAX;
    for (int i = 0; i < runningPauseAnimations.size(); ++i) {
        QAbstractAnimation *animation = runningPauseAnimations.at(i);
        int timeToFinish;

        if (animation->direction() == QAbstractAnimation::Forward)
            timeToFinish = animation->duration() - animation->currentLoopTime();
        else
            timeToFinish = animation->currentLoopTime();

        if (timeToFinish < closestTimeToFinish)
            closestTimeToFinish = timeToFinish;
    }
    return closestTimeToFinish;
}

void QUnifiedTimer::installAnimationDriver(QAnimationDriver *d)
{
    if (driver) {

        if (driver->isRunning()) {
            qWarning("QUnifiedTimer: Cannot change animation driver while animations are running");
            return;
        }

        if (driver != &defaultDriver)
            delete driver;
    }

    driver = d;
}

QAnimationDriver::QAnimationDriver(QObject *parent)
    : QObject(*(new QAnimationDriverPrivate), parent)
{
}

QAnimationDriver::QAnimationDriver(QAnimationDriverPrivate &dd, QObject *parent)
    : QObject(dd, parent)
{
}


void QAnimationDriver::advance()
{
    QUnifiedTimer *instance = QUnifiedTimer::instance();

    // update current time on all top level animations
    instance->updateAnimationsTime();
    instance->restartAnimationTimer();
}


void QAnimationDriver::install()
{
    QUnifiedTimer *timer = QUnifiedTimer::instance(true);
    timer->installAnimationDriver(this);
}

bool QAnimationDriver::isRunning() const
{
    return d_func()->running;
}


void QAnimationDriver::start()
{
    Q_D(QAnimationDriver);
    if (!d->running) {
        started();
        d->running = true;
    }
}


void QAnimationDriver::stop()
{
    Q_D(QAnimationDriver);
    if (d->running) {
        stopped();
        d->running = false;
    }
}

QDefaultAnimationDriver::QDefaultAnimationDriver(QUnifiedTimer *timer)
    : QAnimationDriver(0), m_unified_timer(timer)
{
}

void QDefaultAnimationDriver::timerEvent(QTimerEvent *e)
{
    Q_ASSERT(e->timerId() == m_timer.timerId());
    Q_UNUSED(e); // if the assertions are disabled
    advance();
}

void QDefaultAnimationDriver::started()
{
    m_timer.start(m_unified_timer->timingInterval, this);
}

void QDefaultAnimationDriver::stopped()
{
    m_timer.stop();
}



void QAbstractAnimationPrivate::setState(QAbstractAnimation::State newState)
{
    Q_Q(QAbstractAnimation);
    if (state == newState)
        return;

    if (loopCount == 0)
        return;

    QAbstractAnimation::State oldState = state;
    int oldCurrentTime = currentTime;
    int oldCurrentLoop = currentLoop;
    QAbstractAnimation::Direction oldDirection = direction;

    // check if we should Rewind
    if ((newState == QAbstractAnimation::Paused || newState == QAbstractAnimation::Running)
        && oldState == QAbstractAnimation::Stopped) {
            //here we reset the time if needed
            //we don't call setCurrentTime because this might change the way the animation
            //behaves: changing the state or changing the current value
            totalCurrentTime = currentTime = (direction == QAbstractAnimation::Forward) ?
                0 : (loopCount == -1 ? q->duration() : q->totalDuration());
    }

    state = newState;
    QWeakPointer<QAbstractAnimation> guard(q);

    //(un)registration of the animation must always happen before calls to
    //virtual function (updateState) to ensure a correct state of the timer
    bool isTopLevel = !group || group->state() == QAbstractAnimation::Stopped;
    if (oldState == QAbstractAnimation::Running) {
        if (newState == QAbstractAnimation::Paused && hasRegisteredTimer)
            QUnifiedTimer::ensureTimerUpdate();
        //the animation, is not running any more
        QUnifiedTimer::unregisterAnimation(q);
    } else if (newState == QAbstractAnimation::Running) {
        QUnifiedTimer::registerAnimation(q, isTopLevel);
    }

    q->updateState(newState, oldState);
    if (!guard || newState != state) //this is to be safe if updateState changes the state
        return;

    // Notify state change
    emit q->stateChanged(newState, oldState);
    if (!guard || newState != state) //this is to be safe if updateState changes the state
        return;

    switch (state) {
    case QAbstractAnimation::Paused:
        break;
    case QAbstractAnimation::Running:
        {

            // this ensures that the value is updated now that the animation is running
            if (oldState == QAbstractAnimation::Stopped) {
                if (isTopLevel) {
                    // currentTime needs to be updated if pauseTimer is active
                    QUnifiedTimer::ensureTimerUpdate();
                    q->setCurrentTime(totalCurrentTime);
                }
            }
        }
        break;
    case QAbstractAnimation::Stopped:
        // Leave running state.
        int dura = q->duration();

        if (deleteWhenStopped)
            q->deleteLater();

        if (dura == -1 || loopCount < 0
            || (oldDirection == QAbstractAnimation::Forward && (oldCurrentTime * (oldCurrentLoop + 1)) == (dura * loopCount))
            || (oldDirection == QAbstractAnimation::Backward && oldCurrentTime == 0)) {
                emit q->finished();
        }
        break;
    }
}

QAbstractAnimation::QAbstractAnimation(QObject *parent)
    : QObject(*new QAbstractAnimationPrivate, 0)
{
    // Allow auto-add on reparent
    setParent(parent);
}

QAbstractAnimation::QAbstractAnimation(QAbstractAnimationPrivate &dd, QObject *parent)
    : QObject(dd, 0)
{
    // Allow auto-add on reparent
   setParent(parent);
}

QAbstractAnimation::~QAbstractAnimation()
{
    Q_D(QAbstractAnimation);
    //we can't call stop here. Otherwise we get pure virtual calls
    if (d->state != Stopped) {
        QAbstractAnimation::State oldState = d->state;
        d->state = Stopped;
        emit stateChanged(oldState, d->state);
        if (oldState == QAbstractAnimation::Running)
            QUnifiedTimer::unregisterAnimation(this);
    }
}

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

QAnimationGroup *QAbstractAnimation::group() const
{
    Q_D(const QAbstractAnimation);
    return d->group;
}

QAbstractAnimation::Direction QAbstractAnimation::direction() const
{
    Q_D(const QAbstractAnimation);
    return d->direction;
}
void QAbstractAnimation::setDirection(Direction direction)
{
    Q_D(QAbstractAnimation);
    if (d->direction == direction)
        return;

    if (state() == Stopped) {
        if (direction == Backward) {
            d->currentTime = duration();
            d->currentLoop = d->loopCount - 1;
        } else {
            d->currentTime = 0;
            d->currentLoop = 0;
        }
    }

    // the commands order below is important: first we need to setCurrentTime with the old direction,
    // then update the direction on this and all children and finally restart the pauseTimer if needed
    if (d->hasRegisteredTimer)
        QUnifiedTimer::ensureTimerUpdate();

    d->direction = direction;
    updateDirection(direction);

    if (d->hasRegisteredTimer)
        // needed to update the timer interval in case of a pause animation
        QUnifiedTimer::updateAnimationTimer();

    emit directionChanged(direction);
}

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

int QAbstractAnimation::currentLoop() const
{
    Q_D(const QAbstractAnimation);
    return d->currentLoop;
}

int QAbstractAnimation::totalDuration() const
{
    int dura = duration();
    if (dura <= 0)
        return dura;
    int loopcount = loopCount();
    if (loopcount < 0)
        return -1;
    return dura * loopcount;
}

int QAbstractAnimation::currentLoopTime() const
{
    Q_D(const QAbstractAnimation);
    return d->currentTime;
}

int QAbstractAnimation::currentTime() const
{
    Q_D(const QAbstractAnimation);
    return d->totalCurrentTime;
}
void QAbstractAnimation::setCurrentTime(int msecs)
{
    Q_D(QAbstractAnimation);
    msecs = qMax(msecs, 0);

    // Calculate new time and loop.
    int dura = duration();
    int totalDura = dura <= 0 ? dura : ((d->loopCount < 0) ? -1 : dura * d->loopCount);
    if (totalDura != -1)
        msecs = qMin(totalDura, msecs);
    d->totalCurrentTime = msecs;

    // Update new values.
    int oldLoop = d->currentLoop;
    d->currentLoop = ((dura <= 0) ? 0 : (msecs / dura));
    if (d->currentLoop == d->loopCount) {
        //we're at the end
        d->currentTime = qMax(0, dura);
        d->currentLoop = qMax(0, d->loopCount - 1);
    } else {
        if (d->direction == Forward) {
            d->currentTime = (dura <= 0) ? msecs : (msecs % dura);
        } else {
            d->currentTime = (dura <= 0) ? msecs : ((msecs - 1) % dura) + 1;
            if (d->currentTime == dura)
                --d->currentLoop;
        }
    }

    updateCurrentTime(d->currentTime);
    if (d->currentLoop != oldLoop)
        emit currentLoopChanged(d->currentLoop);

    // All animations are responsible for stopping the animation when their
    // own end state is reached; in this case the animation is time driven,
    // and has reached the end.
    if ((d->direction == Forward && d->totalCurrentTime == totalDura)
        || (d->direction == Backward && d->totalCurrentTime == 0)) {
        stop();
    }
}

void QAbstractAnimation::start(DeletionPolicy policy)
{
    Q_D(QAbstractAnimation);
    if (d->state == Running)
        return;
    d->deleteWhenStopped = policy;
    d->setState(Running);
}

void QAbstractAnimation::stop()
{
    Q_D(QAbstractAnimation);

    if (d->state == Stopped)
        return;

    d->setState(Stopped);
}

void QAbstractAnimation::pause()
{
    Q_D(QAbstractAnimation);
    if (d->state == Stopped) {
        qWarning("QAbstractAnimation::pause: Cannot pause a stopped animation");
        return;
    }

    d->setState(Paused);
}

void QAbstractAnimation::resume()
{
    Q_D(QAbstractAnimation);
    if (d->state != Paused) {
        qWarning("QAbstractAnimation::resume: "
                 "Cannot resume an animation that is not paused");
        return;
    }

    d->setState(Running);
}

void QAbstractAnimation::setPaused(bool paused)
{
    if (paused)
        pause();
    else
        resume();
}


bool QAbstractAnimation::event(QEvent *event)
{
    return QObject::event(event);
}

void QAbstractAnimation::updateState(QAbstractAnimation::State newState,
                                     QAbstractAnimation::State oldState)
{
    Q_UNUSED(oldState);
    Q_UNUSED(newState);
}

void QAbstractAnimation::updateDirection(QAbstractAnimation::Direction direction)
{
    Q_UNUSED(direction);
}


QT_END_NAMESPACE

#include "moc_qabstractanimation.cpp"

#endif //QT_NO_ANIMATION