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++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
++
++ #include "qquickage_p.h"
++ #include "qquickparticleemitter_p.h"
++ QT_BEGIN_NAMESPACE
++ /*!
++ \qmltype Age
++ \nativetype QQuickAgeAffector
++ \inqmlmodule QtQuick.Particles
++ \inherits ParticleAffector
++ \brief For altering particle ages.
++ \ingroup qtquick-particles
++
++ The Age affector allows you to alter where the particle is in its lifecycle. Common uses
++ are to expire particles prematurely, possibly giving them time to animate out.
++
++ The Age affector is also sometimes known as a 'Kill' affector, because with the default
++ parameters it will immediately expire all particles which it affects.
++
++ The Age affector only applies to particles which are still alive.
++ */
++ /*!
++ \qmlproperty int QtQuick.Particles::Age::lifeLeft
++
++ The amount of life to set the particle to have. Affected particles
++ will advance to a point in their life where they will have this many
++ milliseconds left to live.
++ */
++
++ /*!
++ \qmlproperty bool QtQuick.Particles::Age::advancePosition
++
++ advancePosition determines whether position, veclocity and acceleration are included in
++ the simulated aging done by the affector. If advancePosition is false,
++ then the position, velocity and acceleration will remain the same and only
++ other attributes (such as opacity) will advance in the simulation to where
++ it would normally be for that point in the particle's life. With advancePosition set to
++ true the position, velocity and acceleration will also advance to where it would
++ normally be by that point in the particle's life, making it advance its position
++ on screen.
++
++ Default value is true.
++ */
++
++ QQuickAgeAffector::QQuickAgeAffector(QQuickItem *parent) :
++ QQuickParticleAffector(parent), m_lifeLeft(0), m_advancePosition(true)
++ {
++ }
++
++
++ bool QQuickAgeAffector::affectParticle(QQuickParticleData *d, qreal dt)
++ {
++ Q_UNUSED(dt);
++ if (d->stillAlive(m_system)){
++ float curT = m_system->timeInt / 1000.0f;
++ float ttl = m_lifeLeft / 1000.0f;
++ if (!m_advancePosition && ttl > 0){
++ float x = d->curX(m_system);
++ float vx = d->curVX(m_system);
++ float ax = d->curAX();
++ float y = d->curY(m_system);
++ float vy = d->curVY(m_system);
++ float ay = d->curAY();
++ d->t = curT - (d->lifeSpan - ttl);
++ d->setInstantaneousX(x, m_system);
++ d->setInstantaneousVX(vx, m_system);
++ d->setInstantaneousAX(ax, m_system);
++ d->setInstantaneousY(y, m_system);
++ d->setInstantaneousVY(vy, m_system);
++ d->setInstantaneousAY(ay, m_system);
++ } else {
++ d->t = curT - (d->lifeSpan - ttl);
++ }
++ return true;
++ }
++ return false;
++ }
++ QT_END_NAMESPACE
++
++ #include "moc_qquickage_p.cpp"