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diff --git a/src/imports/particles/qdeclarativeparticles.cpp b/src/imports/particles/qdeclarativeparticles.cpp new file mode 100644 index 0000000..bb6669a --- /dev/null +++ b/src/imports/particles/qdeclarativeparticles.cpp @@ -0,0 +1,1330 @@ +/**************************************************************************** +** +** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtDeclarative module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qdeclarativeparticles_p.h" + +#include <private/qdeclarativeitem_p.h> + +#include <private/qdeclarativepixmapcache_p.h> +#include <private/qfxperf_p_p.h> +#include <QtCore/QAbstractAnimation> + +#include <QPainter> +#include <QtGui/qdrawutil.h> +#include <QVarLengthArray> + +#include <stdlib.h> +#include <math.h> + +#ifndef M_PI +#define M_PI 3.14159265358979323846 +#define M_PI_2 (M_PI / 2.) +#endif +#ifndef INT_MAX +#define INT_MAX 2147483647 +#endif + +QT_BEGIN_NAMESPACE +#define PI_SQR 9.8696044 +// parabolic approximation +inline qreal fastSin(qreal theta) +{ + const qreal b = 4 / M_PI; + const qreal c = -4 / PI_SQR; + + qreal y = b * theta + c * theta * qAbs(theta); + return y; +} + +inline qreal fastCos(qreal theta) +{ + theta += M_PI_2; + if (theta > M_PI) + theta -= 2 * M_PI; + + return fastSin(theta); +} + +class QDeclarativeParticle +{ +public: + QDeclarativeParticle(int time) : lifeSpan(1000), fadeOutAge(800) + , opacity(0), birthTime(time), x_velocity(0), y_velocity(0) + , state(FadeIn), data(0) + { + } + + int lifeSpan; + int fadeOutAge; + qreal x; + qreal y; + qreal opacity; + int birthTime; + qreal x_velocity; + qreal y_velocity; + enum State { FadeIn, Solid, FadeOut }; + State state; + void *data; +}; + +//--------------------------------------------------------------------------- + +/*! + \class QDeclarativeParticleMotion + \ingroup group_effects + \brief The QDeclarativeParticleMotion class is the base class for particle motion. + \internal + + This class causes the particles to remain static. +*/ + +/*! + Constructs a QDeclarativeParticleMotion with parent object \a parent. +*/ +QDeclarativeParticleMotion::QDeclarativeParticleMotion(QObject *parent) : + QObject(parent) +{ +} + +/*! + Move the \a particle to its new position. \a interval is the number of + milliseconds elapsed since it was last moved. +*/ +void QDeclarativeParticleMotion::advance(QDeclarativeParticle &particle, int interval) +{ + Q_UNUSED(particle); + Q_UNUSED(interval); +} + +/*! + The \a particle has just been created. Some motion strategies require + additional state information. This can be allocated by this function. +*/ +void QDeclarativeParticleMotion::created(QDeclarativeParticle &particle) +{ + Q_UNUSED(particle); +} + +/*! + The \a particle is about to be destroyed. Any additional memory + that has been allocated for the particle should be freed. +*/ +void QDeclarativeParticleMotion::destroy(QDeclarativeParticle &particle) +{ + Q_UNUSED(particle); +} + +/*! + \qmlclass ParticleMotionLinear + \since 4.7 + \brief The ParticleMotionLinear object moves particles linearly. + + \sa Particles +*/ + +/*! + \internal + \class QDeclarativeParticleMotionLinear + \ingroup group_effects + \brief The QDeclarativeParticleMotionLinear class moves the particles linearly. +*/ + +void QDeclarativeParticleMotionLinear::advance(QDeclarativeParticle &p, int interval) +{ + p.x += interval * p.x_velocity; + p.y += interval * p.y_velocity; +} + +/*! + \qmlclass ParticleMotionGravity + \since 4.7 + \brief The ParticleMotionGravity object moves particles towards a point. + + \sa Particles +*/ + +/*! + \internal + \class QDeclarativeParticleMotionGravity + \ingroup group_effects + \brief The QDeclarativeParticleMotionGravity class moves the particles towards a point. +*/ + +/*! + \qmlproperty qreal ParticleMotionGravity::xattractor + \qmlproperty qreal ParticleMotionGravity::yattractor + These properties hold the x and y coordinates of the point attracting the particles. +*/ + +/*! + \qmlproperty qreal ParticleMotionGravity::acceleration + This property holds the acceleration to apply to the particles. +*/ + +/*! + \property QDeclarativeParticleMotionGravity::xattractor + \brief the x coordinate of the point attracting the particles. +*/ + +/*! + \property QDeclarativeParticleMotionGravity::yattractor + \brief the y coordinate of the point attracting the particles. +*/ + +/*! + \property QDeclarativeParticleMotionGravity::acceleration + \brief the acceleration to apply to the particles. +*/ + +void QDeclarativeParticleMotionGravity::setXAttractor(qreal x) +{ + if (qFuzzyCompare(x, _xAttr)) + return; + _xAttr = x; + emit xattractorChanged(); +} + +void QDeclarativeParticleMotionGravity::setYAttractor(qreal y) +{ + if (qFuzzyCompare(y, _yAttr)) + return; + _yAttr = y; + emit yattractorChanged(); +} + +void QDeclarativeParticleMotionGravity::setAcceleration(qreal accel) +{ + qreal scaledAccel = accel/1000000.0; + if (qFuzzyCompare(scaledAccel, _accel)) + return; + _accel = scaledAccel; + emit accelerationChanged(); +} + +void QDeclarativeParticleMotionGravity::advance(QDeclarativeParticle &p, int interval) +{ + qreal xdiff = p.x - _xAttr; + qreal ydiff = p.y - _yAttr; + + qreal xcomp = xdiff / (xdiff + ydiff); + qreal ycomp = ydiff / (xdiff + ydiff); + + p.x_velocity += xcomp * _accel * interval; + p.y_velocity += ycomp * _accel * interval; + + p.x += interval * p.x_velocity; + p.y += interval * p.y_velocity; +} + +/*! + \qmlclass ParticleMotionWander + \since 4.7 + \brief The ParticleMotionWander object moves particles in a somewhat random fashion. + + The particles will continue roughly in the original direction, however will randomly + drift to each side. + + The code below produces an effect similar to falling snow. + + \qml +Rectangle { + width: 240 + height: 320 + color: "black" + + Particles { + y: 0 + width: parent.width + height: 30 + source: "star.png" + lifeSpan: 5000 + count: 50 + angle: 70 + angleDeviation: 36 + velocity: 30 + velocityDeviation: 10 + ParticleMotionWander { + xvariance: 30 + pace: 100 + } + } +} + \endqml + + \sa Particles +*/ + +/*! + \internal + \class QDeclarativeParticleMotionWander + \ingroup group_effects + \brief The QDeclarativeParticleMotionWander class moves particles in a somewhat random fashion. + + The particles will continue roughly in the original direction, however will randomly + drift to each side. +*/ + +/*! + \qmlproperty qreal QDeclarativeParticleMotionWander::xvariance + \qmlproperty qreal QDeclarativeParticleMotionWander::yvariance + + These properties set the amount to wander in the x and y directions. +*/ + +/*! + \qmlproperty qreal QDeclarativeParticleMotionWander::pace + This property holds how quickly the paricles will move from side to side. +*/ + +void QDeclarativeParticleMotionWander::advance(QDeclarativeParticle &p, int interval) +{ + if (!particles) + particles = qobject_cast<QDeclarativeParticles*>(parent()); + if (particles) { + Data *d = (Data*)p.data; + if (_xvariance != 0.) { + qreal xdiff = p.x_velocity - d->x_targetV; + if ((xdiff > d->x_peak && d->x_var > 0.0) || (xdiff < -d->x_peak && d->x_var < 0.0)) { + d->x_var = -d->x_var; + d->x_peak = _xvariance + _xvariance * qreal(qrand()) / RAND_MAX; + } + p.x_velocity += d->x_var * interval; + } + p.x += interval * p.x_velocity; + + if (_yvariance != 0.) { + qreal ydiff = p.y_velocity - d->y_targetV; + if ((ydiff > d->y_peak && d->y_var > 0.0) || (ydiff < -d->y_peak && d->y_var < 0.0)) { + d->y_var = -d->y_var; + d->y_peak = _yvariance + _yvariance * qreal(qrand()) / RAND_MAX; + } + p.y_velocity += d->y_var * interval; + } + p.y += interval * p.y_velocity; + } +} + +void QDeclarativeParticleMotionWander::created(QDeclarativeParticle &p) +{ + if (!p.data) { + Data *d = new Data; + p.data = (void*)d; + d->x_targetV = p.x_velocity; + d->y_targetV = p.y_velocity; + d->x_peak = _xvariance; + d->y_peak = _yvariance; + d->x_var = _pace * qreal(qrand()) / RAND_MAX / 1000.0; + d->y_var = _pace * qreal(qrand()) / RAND_MAX / 1000.0; + } +} + +void QDeclarativeParticleMotionWander::destroy(QDeclarativeParticle &p) +{ + if (p.data) + delete (Data*)p.data; +} + +void QDeclarativeParticleMotionWander::setXVariance(qreal var) +{ + qreal scaledVar = var / 1000.0; + if (qFuzzyCompare(scaledVar, _xvariance)) + return; + _xvariance = scaledVar; + emit xvarianceChanged(); +} + +void QDeclarativeParticleMotionWander::setYVariance(qreal var) +{ + qreal scaledVar = var / 1000.0; + if (qFuzzyCompare(scaledVar, _yvariance)) + return; + _yvariance = scaledVar; + emit yvarianceChanged(); +} + +void QDeclarativeParticleMotionWander::setPace(qreal pace) +{ + qreal scaledPace = pace / 1000.0; + if (qFuzzyCompare(scaledPace, _pace)) + return; + _pace = scaledPace; + emit paceChanged(); +} + +//--------------------------------------------------------------------------- +class QDeclarativeParticlesPainter : public QDeclarativeItem +{ +public: + QDeclarativeParticlesPainter(QDeclarativeParticlesPrivate *p, QDeclarativeItem* parent) + : QDeclarativeItem(parent), d(p) + { + setFlag(QGraphicsItem::ItemHasNoContents, false); + maxX = minX = maxY = minY = 0; + } + + void paint(QPainter *, const QStyleOptionGraphicsItem *, QWidget *); + + void updateSize(); + + qreal maxX; + qreal minX; + qreal maxY; + qreal minY; + QDeclarativeParticlesPrivate* d; +}; + +//an animation that just gives a tick +template<class T, void (T::*method)(int)> +class TickAnimationProxy : public QAbstractAnimation +{ +public: + TickAnimationProxy(T *p, QObject *parent = 0) : QAbstractAnimation(parent), m_p(p) {} + virtual int duration() const { return -1; } +protected: + virtual void updateCurrentTime(int msec) { (m_p->*method)(msec); } + +private: + T *m_p; +}; + +//--------------------------------------------------------------------------- +class QDeclarativeParticlesPrivate : public QDeclarativeItemPrivate +{ + Q_DECLARE_PUBLIC(QDeclarativeParticles) +public: + QDeclarativeParticlesPrivate() + : count(1), emissionRate(-1), emissionVariance(0.5), lifeSpan(1000) + , lifeSpanDev(1000), fadeInDur(200), fadeOutDur(300) + , angle(0), angleDev(0), velocity(0), velocityDev(0), emissionCarry(0.) + , addParticleTime(0), addParticleCount(0), lastAdvTime(0) + , motion(0), pendingPixmapCache(false), clock(this) + { + } + + ~QDeclarativeParticlesPrivate() + { + } + + void init() + { + Q_Q(QDeclarativeParticles); + paintItem = new QDeclarativeParticlesPainter(this, q); + } + + void tick(int time); + void createParticle(int time); + void updateOpacity(QDeclarativeParticle &p, int age); + + QUrl url; + QPixmap image; + int count; + int emissionRate; + qreal emissionVariance; + int lifeSpan; + int lifeSpanDev; + int fadeInDur; + int fadeOutDur; + qreal angle; + qreal angleDev; + qreal velocity; + qreal velocityDev; + qreal emissionCarry; + int addParticleTime; + int addParticleCount; + int lastAdvTime; + QDeclarativeParticleMotion *motion; + QDeclarativeParticlesPainter *paintItem; + + bool pendingPixmapCache; + + QList<QPair<int, int> > bursts;//countLeft, emissionRate pairs + QList<QDeclarativeParticle> particles; + TickAnimationProxy<QDeclarativeParticlesPrivate, &QDeclarativeParticlesPrivate::tick> clock; + +}; + +void QDeclarativeParticlesPrivate::tick(int time) +{ + Q_Q(QDeclarativeParticles); + if (!motion) + motion = new QDeclarativeParticleMotionLinear(q); + + int oldCount = particles.count(); + int removed = 0; + int interval = time - lastAdvTime; + for (int i = 0; i < particles.count(); ) { + QDeclarativeParticle &particle = particles[i]; + int age = time - particle.birthTime; + if (age >= particle.lifeSpan) { + QDeclarativeParticle part = particles.takeAt(i); + motion->destroy(part); + ++removed; + } else { + updateOpacity(particle, age); + motion->advance(particle, interval); + ++i; + } + } + + if(emissionRate == -1)//Otherwise leave emission to the emission rate + while(removed-- && ((count == -1) || particles.count() < count)) + createParticle(time); + + if (!addParticleTime) + addParticleTime = time; + + //Possibly emit new particles + if (((count == -1) || particles.count() < count) && emissionRate + && !(count==-1 && emissionRate==-1)) { + int emissionCount = -1; + if (emissionRate != -1){ + qreal variance = 1.; + if (emissionVariance > 0.){ + variance += (qreal(qrand())/RAND_MAX) * emissionVariance * (qrand()%2?-1.:1.); + } + qreal emission = emissionRate * (qreal(interval)/1000.); + emission = emission * variance + emissionCarry; + double tmpDbl; + emissionCarry = modf(emission, &tmpDbl); + emissionCount = (int)tmpDbl; + emissionCount = qMax(0,emissionCount); + } + while(((count == -1) || particles.count() < count) && + (emissionRate==-1 || emissionCount--)) + createParticle(time); + } + + //Deal with emissions from requested bursts + for(int i=0; i<bursts.size(); i++){ + int emission = 0; + if(bursts[i].second == -1){ + emission = bursts[i].first; + }else{ + qreal variance = 1.; + if (emissionVariance > 0.){ + variance += (qreal(qrand())/RAND_MAX) * emissionVariance * (qrand()%2?-1.:1.); + } + qreal workingEmission = bursts[i].second * (qreal(interval)/1000.); + workingEmission *= variance; + emission = (int)workingEmission; + emission = qMax(emission, 0); + } + emission = qMin(emission, bursts[i].first); + bursts[i].first -= emission; + while(emission--) + createParticle(time); + } + for(int i=bursts.size()-1; i>=0; i--) + if(bursts[i].first <= 0) + bursts.removeAt(i); + + lastAdvTime = time; + paintItem->updateSize(); + paintItem->update(); + if (!(oldCount || particles.count()) && (!count || !emissionRate) && bursts.isEmpty()) { + lastAdvTime = 0; + clock.stop(); + } +} + +void QDeclarativeParticlesPrivate::createParticle(int time) +{ +#ifdef Q_ENABLE_PERFORMANCE_LOG + QDeclarativePerfTimer<QDeclarativePerf::CreateParticle> x; +#endif + Q_Q(QDeclarativeParticles); + QDeclarativeParticle p(time); + p.x = q->x() + q->width() * qreal(qrand()) / RAND_MAX - image.width()/2.0; + p.y = q->y() + q->height() * qreal(qrand()) / RAND_MAX - image.height()/2.0; + p.lifeSpan = lifeSpan; + if (lifeSpanDev) + p.lifeSpan += int(lifeSpanDev/2 - lifeSpanDev * qreal(qrand()) / RAND_MAX); + p.fadeOutAge = p.lifeSpan - fadeOutDur; + if (fadeInDur == 0.) { + p.state= QDeclarativeParticle::Solid; + p.opacity = 1.0; + } + qreal a = angle; + if (angleDev) + a += angleDev/2 - angleDev * qreal(qrand()) / RAND_MAX; + if (a > M_PI) + a = a - 2 * M_PI; + qreal v = velocity; + if (velocityDev) + v += velocityDev/2 - velocityDev * qreal(qrand()) / RAND_MAX; + p.x_velocity = v * fastCos(a); + p.y_velocity = v * fastSin(a); + particles.append(p); + motion->created(particles.last()); +} + +void QDeclarativeParticlesPrivate::updateOpacity(QDeclarativeParticle &p, int age) +{ + switch (p.state) { + case QDeclarativeParticle::FadeIn: + if (age <= fadeInDur) { + p.opacity = qreal(age) / fadeInDur; + break; + } else { + p.opacity = 1.0; + p.state = QDeclarativeParticle::Solid; + // Fall through + } + case QDeclarativeParticle::Solid: + if (age <= p.fadeOutAge) { + break; + } else { + p.state = QDeclarativeParticle::FadeOut; + // Fall through + } + case QDeclarativeParticle::FadeOut: + p.opacity = qreal(p.lifeSpan - age) / fadeOutDur; + break; + } +} + +/*! + \qmlclass Particles + \since 4.7 + \brief The Particles object generates and moves particles. + \inherits Item + + This element provides preliminary support for particles in QML, + and may be heavily changed or removed in later versions. + + The particles created by this object cannot be dealt with + directly, they can only be controlled through the parameters of + the Particles object. The particles are all the same pixmap, + specified by the user. + + The particles are painted relative to the parent of the Particles + object. Moving the Particles object will not move the particles + already emitted. + + The below example creates two differently behaving particle + sources. The top one has particles falling from the top like + snow, the lower one has particles expelled up like a fountain. + + \qml +Rectangle { + width: 240 + height: 320 + color: "black" + Particles { + y: 0 + width: parent.width + height: 30 + source: "star.png" + lifeSpan: 5000 + count: 50 + angle: 70 + angleDeviation: 36 + velocity: 30 + velocityDeviation: 10 + ParticleMotionWander { + xvariance: 30 + pace: 100 + } + } + Particles { + y: 300 + x: 120 + width: 1 + height: 1 + source: "star.png" + lifeSpan: 5000 + count: 200 + angle: 270 + angleDeviation: 45 + velocity: 50 + velocityDeviation: 30 + ParticleMotionGravity { + yattractor: 1000 + xattractor: 0 + acceleration: 25 + } + } +} + \endqml + \image particles.gif +*/ + +/*! + \internal + \class QDeclarativeParticles + \ingroup group_effects + \brief The QDeclarativeParticles class generates and moves particles. +*/ + +QDeclarativeParticles::QDeclarativeParticles(QDeclarativeItem *parent) + : QDeclarativeItem(*(new QDeclarativeParticlesPrivate), parent) +{ + Q_D(QDeclarativeParticles); + d->init(); +} + +QDeclarativeParticles::~QDeclarativeParticles() +{ + Q_D(QDeclarativeParticles); + if (d->pendingPixmapCache) + QDeclarativePixmapCache::cancel(d->url, this); +} + +/*! + \qmlproperty string Particles::source + This property holds the URL of the particle image. +*/ + +/*! + \property QDeclarativeParticles::source + \brief the URL of the particle image. +*/ +QUrl QDeclarativeParticles::source() const +{ + Q_D(const QDeclarativeParticles); + return d->url; +} + +void QDeclarativeParticles::imageLoaded() +{ + Q_D(QDeclarativeParticles); + d->pendingPixmapCache = false; + QDeclarativePixmapCache::get(d->url, &d->image); + d->paintItem->updateSize(); + d->paintItem->update(); +} + +void QDeclarativeParticles::setSource(const QUrl &name) +{ + Q_D(QDeclarativeParticles); + + if ((d->url.isEmpty() == name.isEmpty()) && name == d->url) + return; + + if (d->pendingPixmapCache) { + QDeclarativePixmapCache::cancel(d->url, this); + d->pendingPixmapCache = false; + } + if (name.isEmpty()) { + d->url = name; + d->image = QPixmap(); + d->paintItem->updateSize(); + d->paintItem->update(); + } else { + d->url = name; + Q_ASSERT(!name.isRelative()); + QDeclarativePixmapReply::Status status = QDeclarativePixmapCache::get(d->url, &d->image); + if (status != QDeclarativePixmapReply::Ready && status != QDeclarativePixmapReply::Error) { + QDeclarativePixmapReply *reply = QDeclarativePixmapCache::request(qmlEngine(this), d->url); + connect(reply, SIGNAL(finished()), this, SLOT(imageLoaded())); + d->pendingPixmapCache = true; + } else { + //### unify with imageLoaded + d->paintItem->updateSize(); + d->paintItem->update(); + } + } + emit sourceChanged(); +} + +/*! + \qmlproperty int Particles::count + This property holds the maximum number of particles + + The particles element emits particles until it has count active + particles. When this number is reached, new particles are not emitted until + some of the current particles reach the end of their lifespan. + + If count is -1 then there is no maximum number of active particles, and + particles will be constantly emitted at the rate specified by emissionRate. + + The default value for count is 1. + + If both count and emissionRate are set to -1, nothing will be emitted. + +*/ + +/*! + \property QDeclarativeParticles::count + \brief the maximum number of particles +*/ +int QDeclarativeParticles::count() const +{ + Q_D(const QDeclarativeParticles); + return d->count; +} + +void QDeclarativeParticles::setCount(int cnt) +{ + Q_D(QDeclarativeParticles); + if (cnt == d->count) + return; + + int oldCount = d->count; + d->count = cnt; + d->addParticleTime = 0; + d->addParticleCount = d->particles.count(); + if (!oldCount && d->clock.state() != QAbstractAnimation::Running && d->count && d->emissionRate) { + d->clock.start(); + } + d->paintItem->updateSize(); + d->paintItem->update(); + emit countChanged(); +} + + +/*! + \qmlproperty int Particles::emissionRate + This property holds the target number of particles to emit every second. + + The particles element will emit up to emissionRate particles every + second. Fewer particles may be emitted per second if the maximum number of + particles has been reached. + + If emissionRate is set to -1 there is no limit to the number of + particles emitted per second, and particles will be instantly emitted to + reach the maximum number of particles specified by count. + + The default value for emissionRate is -1. + + If both count and emissionRate are set to -1, nothing will be emitted. +*/ + +/*! + \property QDeclarativeParticles::emissionRate + \brief the emission rate of particles +*/ +int QDeclarativeParticles::emissionRate() const +{ + Q_D(const QDeclarativeParticles); + return d->emissionRate; +} +void QDeclarativeParticles::setEmissionRate(int er) +{ + Q_D(QDeclarativeParticles); + if(er == d->emissionRate) + return; + d->emissionRate = er; + if (d->clock.state() != QAbstractAnimation::Running && d->count && d->emissionRate) { + d->clock.start(); + } + emit emissionRateChanged(); +} + +/*! + \qmlproperty qreal Particles::emissionVariance + This property holds how inconsistent the rate of particle emissions are. + It is a number between 0 (no variance) and 1 (some variance). + + The expected number of particles emitted per second is emissionRate. If + emissionVariance is 0 then particles will be emitted consistently throughout + each second to reach that number. If emissionVariance is greater than 0 the + rate of particle emission will vary randomly throughout the second, with the + consequence that the actual number of particles emitted in one second will + vary randomly as well. + + emissionVariance is the maximum deviation from emitting + emissionRate particles per second. An emissionVariance of 0 means you should + get exactly emissionRate particles emitted per second, + and an emissionVariance of 1 means you will get between zero and two times + emissionRate particles per second, but you should get emissionRate particles + per second on average. + + Note that even with an emissionVariance of 0 there may be some variance due + to performance and hardware constraints. + + The default value of emissionVariance is 0.5 +*/ + +/*! + \property QDeclarativeParticles::emissionVariance + \brief how much the particle emission amounts vary per tick +*/ + +qreal QDeclarativeParticles::emissionVariance() const +{ + Q_D(const QDeclarativeParticles); + return d->emissionVariance; +} + +void QDeclarativeParticles::setEmissionVariance(qreal ev) +{ + Q_D(QDeclarativeParticles); + if(d->emissionVariance == ev) + return; + d->emissionVariance = ev; + emit emissionVarianceChanged(); +} + +/*! + \qmlproperty int Particles::lifeSpan + \qmlproperty int Particles::lifeSpanDeviation + + These properties describe the life span of each particle. + + The default lifespan for a particle is 1000ms. + + lifeSpanDeviation randomly varies the lifeSpan up to the specified variation. For + example, the following creates particles whose lifeSpan will vary + from 150ms to 250ms: + + \qml +Particles { + source: "star.png" + lifeSpan: 200 + lifeSpanDeviation: 100 +} + \endqml +*/ + +/*! + \property QDeclarativeParticles::lifeSpan + \brief the life span of each particle. + + Default value is 1000ms. + + \sa QDeclarativeParticles::lifeSpanDeviation +*/ +int QDeclarativeParticles::lifeSpan() const +{ + Q_D(const QDeclarativeParticles); + return d->lifeSpan; +} + +void QDeclarativeParticles::setLifeSpan(int ls) +{ + Q_D(QDeclarativeParticles); + if(d->lifeSpan == ls) + return; + d->lifeSpan = ls; + emit lifeSpanChanged(); +} + +/*! + \property QDeclarativeParticles::lifeSpanDeviation + \brief the maximum possible deviation from the set lifeSpan. + + Randomly varies the lifeSpan up to the specified variation. For + example, the following creates particles whose lifeSpan will vary + from 150ms to 250ms: + +\qml +Particles { + source: "star.png" + lifeSpan: 200 + lifeSpanDeviation: 100 +} +\endqml + + \sa QDeclarativeParticles::lifeSpan +*/ +int QDeclarativeParticles::lifeSpanDeviation() const +{ + Q_D(const QDeclarativeParticles); + return d->lifeSpanDev; +} + +void QDeclarativeParticles::setLifeSpanDeviation(int dev) +{ + Q_D(QDeclarativeParticles); + if(d->lifeSpanDev == dev) + return; + d->lifeSpanDev = dev; + emit lifeSpanDeviationChanged(); +} + +/*! + \qmlproperty int Particles::fadeInDuration + \qmlproperty int Particles::fadeOutDuration + These properties hold the time taken to fade the particles in and out. + + By default fade in is 200ms and fade out is 300ms. +*/ + +/*! + \property QDeclarativeParticles::fadeInDuration + \brief the time taken to fade in the particles. + + Default value is 200ms. +*/ +int QDeclarativeParticles::fadeInDuration() const +{ + Q_D(const QDeclarativeParticles); + return d->fadeInDur; +} + +void QDeclarativeParticles::setFadeInDuration(int dur) +{ + Q_D(QDeclarativeParticles); + if (dur < 0.0 || dur == d->fadeInDur) + return; + d->fadeInDur = dur; + emit fadeInDurationChanged(); +} + +/*! + \property QDeclarativeParticles::fadeOutDuration + \brief the time taken to fade out the particles. + + Default value is 300ms. +*/ +int QDeclarativeParticles::fadeOutDuration() const +{ + Q_D(const QDeclarativeParticles); + return d->fadeOutDur; +} + +void QDeclarativeParticles::setFadeOutDuration(int dur) +{ + Q_D(QDeclarativeParticles); + if (dur < 0.0 || d->fadeOutDur == dur) + return; + d->fadeOutDur = dur; + emit fadeOutDurationChanged(); +} + +/*! + \qmlproperty real Particles::angle + \qmlproperty real Particles::angleDeviation + + These properties control particle direction. + + angleDeviation randomly varies the direction up to the specified variation. For + example, the following creates particles whose initial direction will + vary from 15 degrees to 105 degrees: + + \qml +Particles { + source: "star.png" + angle: 60 + angleDeviation: 90 +} + \endqml +*/ + +/*! + \property QDeclarativeParticles::angle + \brief the initial angle of direction. + + \sa QDeclarativeParticles::angleDeviation +*/ +qreal QDeclarativeParticles::angle() const +{ + Q_D(const QDeclarativeParticles); + return d->angle * 180.0 / M_PI; +} + +void QDeclarativeParticles::setAngle(qreal angle) +{ + Q_D(QDeclarativeParticles); + qreal radAngle = angle * M_PI / 180.0; + if(radAngle == d->angle) + return; + d->angle = radAngle; + emit angleChanged(); +} + +/*! + \property QDeclarativeParticles::angleDeviation + \brief the maximum possible deviation from the set angle. + + Randomly varies the direction up to the specified variation. For + example, the following creates particles whose initial direction will + vary from 15 degrees to 105 degrees: + +\qml +Particles { + source: "star.png" + angle: 60 + angleDeviation: 90 +} +\endqml + + \sa QDeclarativeParticles::angle +*/ +qreal QDeclarativeParticles::angleDeviation() const +{ + Q_D(const QDeclarativeParticles); + return d->angleDev * 180.0 / M_PI; +} + +void QDeclarativeParticles::setAngleDeviation(qreal dev) +{ + Q_D(QDeclarativeParticles); + qreal radDev = dev * M_PI / 180.0; + if(radDev == d->angleDev) + return; + d->angleDev = radDev; + emit angleDeviationChanged(); +} + +/*! + \qmlproperty real Particles::velocity + \qmlproperty real Particles::velocityDeviation + + These properties control the velocity of the particles. + + velocityDeviation randomly varies the velocity up to the specified variation. For + example, the following creates particles whose initial velocity will + vary from 40 to 60. + + \qml +Particles { + source: "star.png" + velocity: 50 + velocityDeviation: 20 +} + \endqml +*/ + +/*! + \property QDeclarativeParticles::velocity + \brief the initial velocity of the particles. + + \sa QDeclarativeParticles::velocityDeviation +*/ +qreal QDeclarativeParticles::velocity() const +{ + Q_D(const QDeclarativeParticles); + return d->velocity * 1000.0; +} + +void QDeclarativeParticles::setVelocity(qreal velocity) +{ + Q_D(QDeclarativeParticles); + qreal realVel = velocity / 1000.0; + if(realVel == d->velocity) + return; + d->velocity = realVel; + emit velocityChanged(); +} + +/*! + \property QDeclarativeParticles::velocityDeviation + \brief the maximum possible deviation from the set velocity. + + Randomly varies the velocity up to the specified variation. For + example, the following creates particles whose initial velocity will + vary from 40 to 60. + +\qml +Particles { + source: "star.png" + velocity: 50 + velocityDeviation: 20 +} +\endqml + + \sa QDeclarativeParticles::velocity +*/ +qreal QDeclarativeParticles::velocityDeviation() const +{ + Q_D(const QDeclarativeParticles); + return d->velocityDev * 1000.0; +} + +void QDeclarativeParticles::setVelocityDeviation(qreal velocity) +{ + Q_D(QDeclarativeParticles); + qreal realDev = velocity / 1000.0; + if(realDev == d->velocityDev) + return; + d->velocityDev = realDev; + emit velocityDeviationChanged(); +} + +/*! + \qmlproperty ParticleMotion Particles::motion + This property sets the type of motion to apply to the particles. + + When a particle is created it will have an initial direction and velocity. + The motion of the particle during its lifeSpan is then influenced by the + motion property. + + Default motion is ParticleMotionLinear. +*/ + +/*! + \property QDeclarativeParticles::motion + \brief sets the type of motion to apply to the particles. + + When a particle is created it will have an initial direction and velocity. + The motion of the particle during its lifeSpan is then influenced by the + motion property. + + Default motion is QDeclarativeParticleMotionLinear. +*/ +QDeclarativeParticleMotion *QDeclarativeParticles::motion() const +{ + Q_D(const QDeclarativeParticles); + return d->motion; +} + +void QDeclarativeParticles::setMotion(QDeclarativeParticleMotion *motion) +{ + Q_D(QDeclarativeParticles); + if (motion == d->motion) + return; + d->motion = motion; + emit motionChanged(); +} + +/*! + \qmlmethod Particles::burst(int count, int emissionRate) + + Initiates a burst of particles. + + This method takes two arguments. The first argument is the number + of particles to emit and the second argument is the emissionRate for the + burst. If the second argument is omitted, it is treated as -1. The burst + of particles has a separate emissionRate and count to the normal emission of + particles. The burst uses the same values as normal emission for all other + properties, including emissionVariance. + + The normal emission of particles will continue during the burst, however + the particles created by the burst count towards the maximum number used by + normal emission. To avoid this behavior, use two Particles elements. + +*/ +void QDeclarativeParticles::burst(int count, int emissionRate) +{ + Q_D(QDeclarativeParticles); + d->bursts << qMakePair(count, emissionRate); + if (d->clock.state() != QAbstractAnimation::Running) + d->clock.start(); +} + +void QDeclarativeParticlesPainter::updateSize() +{ + if (!d->_componentComplete) + return; + + const int parentX = parentItem()->x(); + const int parentY = parentItem()->y(); + for (int i = 0; i < d->particles.count(); ++i) { + const QDeclarativeParticle &particle = d->particles.at(i); + if(particle.x > maxX) + maxX = particle.x; + if(particle.x < minX) + minX = particle.x; + if(particle.y > maxY) + maxY = particle.y; + if(particle.y < minY) + minY = particle.y; + } + + int myWidth = (int)(maxX-minX+0.5)+d->image.width(); + int myX = (int)(minX - parentX); + int myHeight = (int)(maxY-minY+0.5)+d->image.height(); + int myY = (int)(minY - parentY); + setWidth(myWidth); + setHeight(myHeight); + setX(myX); + setY(myY); +} + +void QDeclarativeParticles::paint(QPainter *p, const QStyleOptionGraphicsItem *, QWidget *) +{ + Q_UNUSED(p); + //painting is done by the ParticlesPainter, so it can have the right size +} + +void QDeclarativeParticlesPainter::paint(QPainter *p, const QStyleOptionGraphicsItem *, QWidget *) +{ + if (d->image.isNull() || d->particles.isEmpty()) + return; + + const int myX = x() + parentItem()->x(); + const int myY = y() + parentItem()->y(); + +#if (QT_VERSION >= QT_VERSION_CHECK(4,7,0)) + QVarLengthArray<QPainter::PixmapFragment, 256> pixmapData; +#else + QVarLengthArray<QDrawPixmaps::Data, 256> pixmapData; +#endif + pixmapData.resize(d->particles.count()); + + const QRectF sourceRect = d->image.rect(); + qreal halfPWidth = sourceRect.width()/2.; + qreal halfPHeight = sourceRect.height()/2.; + for (int i = 0; i < d->particles.count(); ++i) { + const QDeclarativeParticle &particle = d->particles.at(i); +#if (QT_VERSION >= QT_VERSION_CHECK(4,7,0)) + pixmapData[i].x = particle.x - myX + halfPWidth; + pixmapData[i].y = particle.y - myY + halfPHeight; +#else + pixmapData[i].point = QPointF(particle.x - myX + halfPWidth, particle.y - myY + halfPHeight); +#endif + pixmapData[i].opacity = particle.opacity; + + //these never change + pixmapData[i].rotation = 0; + pixmapData[i].scaleX = 1; + pixmapData[i].scaleY = 1; +#if (QT_VERSION >= QT_VERSION_CHECK(4,7,0)) + pixmapData[i].sourceLeft = sourceRect.left(); + pixmapData[i].sourceTop = sourceRect.top(); + pixmapData[i].width = sourceRect.width(); + pixmapData[i].height = sourceRect.height(); +#else + pixmapData[i].source = sourceRect; +#endif + } +#if (QT_VERSION >= QT_VERSION_CHECK(4,7,0)) + p->drawPixmapFragments(pixmapData.data(), d->particles.count(), d->image); +#else + qDrawPixmaps(p, pixmapData.data(), d->particles.count(), d->image); +#endif +} + +void QDeclarativeParticles::componentComplete() +{ + Q_D(QDeclarativeParticles); + QDeclarativeItem::componentComplete(); + if (d->count && d->emissionRate) { + d->paintItem->updateSize(); + d->clock.start(); + } + if (d->lifeSpanDev > d->lifeSpan) + d->lifeSpanDev = d->lifeSpan; +} + +QT_END_NAMESPACE |