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 != 0. &&
((trackVelocity > 0) == ((initialValue - to) > 0));
if (hasReversed) {
switch (reversingMode) {
default:
case QDeclarativeSmoothedAnimation::Eased:
break;
case QDeclarativeSmoothedAnimation::Sync:
QDeclarativePropertyPrivate::write(target, to,
QDeclarativePropertyPrivate::BypassInterceptor
| QDeclarativePropertyPrivate::DontRemoveBinding);
stop();
return;
case QDeclarativeSmoothedAnimation::Immediate:
initialVelocity = 0;
delayedStop();
break;
}
}
trackVelocity = initialVelocity;
invert = (to < initialValue);
if (!recalc()) {
QDeclarativePropertyPrivate::write(target, to,
QDeclarativePropertyPrivate::BypassInterceptor
| QDeclarativePropertyPrivate::DontRemoveBinding);
stop();
return;
}
}
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;
}
