qdeclarativesmoothedanimation.cpp

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#include "private/qdeclarativesmoothedanimation_p.h"
#include "private/qdeclarativesmoothedanimation_p_p.h"

#include "private/qdeclarativeanimation_p_p.h"

#include <qdeclarativeproperty.h>
#include "private/qdeclarativeproperty_p.h"

#include "private/qdeclarativeglobal_p.h"

#include <QtCore/qdebug.h>

#include <QtCore/qmath.h>

#define DELAY_STOP_TIMER_INTERVAL 32

QT_BEGIN_NAMESPACE

QSmoothedAnimation::QSmoothedAnimation(QObject *parent)
    : QAbstractAnimation(parent), to(0), velocity(200), userDuration(-1), maximumEasingTime(-1),
      reversingMode(QDeclarativeSmoothedAnimation::Eased), initialVelocity(0),
      trackVelocity(0), initialValue(0), invert(false), finalDuration(-1), lastTime(0)
{
    delayedStopTimer.setInterval(DELAY_STOP_TIMER_INTERVAL);
    delayedStopTimer.setSingleShot(true);
    connect(&delayedStopTimer, SIGNAL(timeout()), this, SLOT(stop()));
}

void QSmoothedAnimation::restart()
{
    initialVelocity = trackVelocity;
    if (state() != QAbstractAnimation::Running)
        start();
    else
        init();
}

void QSmoothedAnimation::updateState(QAbstractAnimation::State newState, QAbstractAnimation::State /*oldState*/)
{
    if (newState == QAbstractAnimation::Running)
        init();
}

void QSmoothedAnimation::delayedStop()
{
    if (!delayedStopTimer.isActive())
        delayedStopTimer.start();
}

int QSmoothedAnimation::duration() const
{
    return -1;
}

bool QSmoothedAnimation::recalc()
{
    s = to - initialValue;
    vi = initialVelocity;

    s = (invert? qreal(-1.0): qreal(1.0)) * s;

    if (userDuration > 0 && velocity > 0) {
        tf = s / velocity;
        if (tf > (userDuration / qreal(1000.))) tf = (userDuration / qreal(1000.));
    } else if (userDuration > 0) {
        tf = userDuration / qreal(1000.);
    } else if (velocity > 0) {
        tf = s / velocity;
    } else {
        return false;
    }

    finalDuration = ceil(tf * qreal(1000.0));

    if (maximumEasingTime == 0) {
        a = 0;
        d = 0;
        tp = 0;
        td = tf;
        vp = velocity;
        sp = 0;
        sd = s;
    } else if (maximumEasingTime != -1 && tf > (maximumEasingTime / qreal(1000.))) {
        qreal met = maximumEasingTime / qreal(1000.);
        td = tf - met;

        qreal c1 = td;
        qreal c2 = (tf - td) * vi - tf * velocity;
        qreal c3 = qreal(-0.5) * (tf - td) * vi * vi;

        qreal vp1 = (-c2 + qSqrt(c2 * c2 - 4 * c1 * c3)) / (qreal(2.) * c1);

        vp = vp1;
        a = vp / met;
        d = a;
        tp = (vp - vi) / a;
        sp = vi * tp + qreal(0.5) * a * tp * tp;
        sd = sp + (td - tp) * vp;
    } else {
        qreal c1 = qreal(0.25) * tf * tf;
        qreal c2 = qreal(0.5) * vi * tf - s;
        qreal c3 = qreal(-0.25) * vi * vi;

        qreal a1 = (-c2 + qSqrt(c2 * c2 - 4 * c1 * c3)) / (qreal(2.) * c1);

        qreal tp1 = qreal(0.5) * tf - qreal(0.5) * vi / a1;
        qreal vp1 = a1 * tp1 + vi;

        qreal sp1 = qreal(0.5) * a1 * tp1 * tp1 + vi * tp1;

        a = a1;
        d = a1;
        tp = tp1;
        td = tp1;
        vp = vp1;
        sp = sp1;
        sd = sp1;
    }
    return true;
}

qreal QSmoothedAnimation::easeFollow(qreal time_seconds)
{
    qreal value;
    if (time_seconds < tp) {
        trackVelocity = vi + time_seconds * a;
        value = qreal(0.5) * a * time_seconds * time_seconds + vi * time_seconds;
    } else if (time_seconds < td) {
        time_seconds -= tp;
        trackVelocity = vp;
        value = sp + time_seconds * vp;
    } else if (time_seconds < tf) {
        time_seconds -= td;
        trackVelocity = vp - time_seconds * a;
        value = sd - qreal(0.5) * d * time_seconds * time_seconds + vp * time_seconds;
    } else {
        trackVelocity = 0;
        value = s;
        delayedStop();
    }

    // to normalize 's' between [0..1], divide 'value' by 's'
    return value;
}

void QSmoothedAnimation::updateCurrentTime(int t)
{
    qreal time_seconds = qreal(t - lastTime) / qreal(1000.);

    qreal value = easeFollow(time_seconds);
    value *= (invert? qreal(-1.0): qreal(1.0));
    QDeclarativePropertyPrivate::write(target, initialValue + value,
                                       QDeclarativePropertyPrivate::BypassInterceptor
                                       | QDeclarativePropertyPrivate::DontRemoveBinding);
}

void QSmoothedAnimation::init()
{
    if (velocity == 0) {
        stop();
        return;
    }

    if (delayedStopTimer.isActive())
        delayedStopTimer.stop();

    initialValue = target.read().toReal();
    lastTime = this->currentTime();

    if (to == initialValue) {
        stop();
        return;
    }

    bool hasReversed = trackVelocity != qreal(0.) &&
                      ((!invert) == ((initialValue - to) > 0));

    if (hasReversed) {
        switch (reversingMode) {
            default:
            case QDeclarativeSmoothedAnimation::Eased:
                initialVelocity = -trackVelocity;
                break;
            case QDeclarativeSmoothedAnimation::Sync:
                QDeclarativePropertyPrivate::write(target, to,
                                                   QDeclarativePropertyPrivate::BypassInterceptor
                                                   | QDeclarativePropertyPrivate::DontRemoveBinding);
                trackVelocity = 0;
                stop();
                return;
            case QDeclarativeSmoothedAnimation::Immediate:
                initialVelocity = 0;
                break;
        }
    }

    trackVelocity = initialVelocity;

    invert = (to < initialValue);

    if (!recalc()) {
        QDeclarativePropertyPrivate::write(target, to,
                                           QDeclarativePropertyPrivate::BypassInterceptor
                                           | QDeclarativePropertyPrivate::DontRemoveBinding);
        stop();
        return;
    }
}

QDeclarativeSmoothedAnimation::QDeclarativeSmoothedAnimation(QObject *parent)
: QDeclarativeNumberAnimation(*(new QDeclarativeSmoothedAnimationPrivate), parent)
{
}

QDeclarativeSmoothedAnimation::~QDeclarativeSmoothedAnimation()
{
}

QDeclarativeSmoothedAnimationPrivate::QDeclarativeSmoothedAnimationPrivate()
    : wrapperGroup(new QParallelAnimationGroup), anim(new QSmoothedAnimation)
{
    Q_Q(QDeclarativeSmoothedAnimation);
    QDeclarative_setParent_noEvent(wrapperGroup, q);
    QDeclarative_setParent_noEvent(anim, q);
}

void QDeclarativeSmoothedAnimationPrivate::updateRunningAnimations()
{
    foreach(QSmoothedAnimation* ease, activeAnimations.values()){
        ease->maximumEasingTime = anim->maximumEasingTime;
        ease->reversingMode = anim->reversingMode;
        ease->velocity = anim->velocity;
        ease->userDuration = anim->userDuration;
        ease->init();
    }
}

QAbstractAnimation* QDeclarativeSmoothedAnimation::qtAnimation()
{
    Q_D(QDeclarativeSmoothedAnimation);
    return d->wrapperGroup;
}

void QDeclarativeSmoothedAnimation::transition(QDeclarativeStateActions &actions,
                                               QDeclarativeProperties &modified,
                                               TransitionDirection direction)
{
    Q_D(QDeclarativeSmoothedAnimation);
    QDeclarativeNumberAnimation::transition(actions, modified, direction);

    if (!d->actions)
        return;

    QSet<QAbstractAnimation*> anims;
    for (int i = 0; i < d->actions->size(); i++) {
        QSmoothedAnimation *ease;
        bool needsRestart;
        if (!d->activeAnimations.contains((*d->actions)[i].property)) {
            ease = new QSmoothedAnimation();
            d->wrapperGroup->addAnimation(ease);
            d->activeAnimations.insert((*d->actions)[i].property, ease);
            needsRestart = false;
        } else {
            ease = d->activeAnimations.value((*d->actions)[i].property);
            needsRestart = true;
        }
        ease->target = (*d->actions)[i].property;
        ease->to = (*d->actions)[i].toValue.toReal();

        // copying public members from main value holder animation
        ease->maximumEasingTime = d->anim->maximumEasingTime;
        ease->reversingMode = d->anim->reversingMode;
        ease->velocity = d->anim->velocity;
        ease->userDuration = d->anim->userDuration;

        ease->initialVelocity = ease->trackVelocity;

        if (needsRestart)
            ease->init();
        anims.insert(ease);
    }

    for (int i = d->wrapperGroup->animationCount() - 1; i >= 0 ; --i) {
        if (!anims.contains(d->wrapperGroup->animationAt(i))) {
            QSmoothedAnimation *ease = static_cast<QSmoothedAnimation*>(d->wrapperGroup->animationAt(i));
            d->activeAnimations.remove(ease->target);
            d->wrapperGroup->takeAnimation(i);
            delete ease;
        }
    }
}

QDeclarativeSmoothedAnimation::ReversingMode QDeclarativeSmoothedAnimation::reversingMode() const
{
    Q_D(const QDeclarativeSmoothedAnimation);
    return (QDeclarativeSmoothedAnimation::ReversingMode) d->anim->reversingMode;
}

void QDeclarativeSmoothedAnimation::setReversingMode(ReversingMode m)
{
    Q_D(QDeclarativeSmoothedAnimation);
    if (d->anim->reversingMode == m)
        return;

    d->anim->reversingMode = m;
    emit reversingModeChanged();
    d->updateRunningAnimations();
}

int QDeclarativeSmoothedAnimation::duration() const
{
    Q_D(const QDeclarativeSmoothedAnimation);
    return d->anim->userDuration;
}

void QDeclarativeSmoothedAnimation::setDuration(int duration)
{
    Q_D(QDeclarativeSmoothedAnimation);
    if (duration != -1)
        QDeclarativeNumberAnimation::setDuration(duration);
    if(duration == d->anim->userDuration)
        return;
    d->anim->userDuration = duration;
    d->updateRunningAnimations();
}

qreal QDeclarativeSmoothedAnimation::velocity() const
{
    Q_D(const QDeclarativeSmoothedAnimation);
    return d->anim->velocity;
}

void QDeclarativeSmoothedAnimation::setVelocity(qreal v)
{
    Q_D(QDeclarativeSmoothedAnimation);
    if (d->anim->velocity == v)
        return;

    d->anim->velocity = v;
    emit velocityChanged();
    d->updateRunningAnimations();
}

int QDeclarativeSmoothedAnimation::maximumEasingTime() const
{
    Q_D(const QDeclarativeSmoothedAnimation);
    return d->anim->maximumEasingTime;
}

void QDeclarativeSmoothedAnimation::setMaximumEasingTime(int v)
{
    Q_D(QDeclarativeSmoothedAnimation);
    if(v == d->anim->maximumEasingTime)
        return;
    d->anim->maximumEasingTime = v;
    emit maximumEasingTimeChanged();
    d->updateRunningAnimations();
}

QT_END_NAMESPACE