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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 "qquicktargetdirection_p.h"
++ #include "qquickparticleemitter_p.h"
++ #include <cmath>
++ #include <QDebug>
++ #include <QRandomGenerator>
++
++ QT_BEGIN_NAMESPACE
++ /*!
++ \qmltype TargetDirection
++ \nativetype QQuickTargetDirection
++ \inqmlmodule QtQuick.Particles
++ \ingroup qtquick-particles
++ \inherits Direction
++ \brief For specifying a direction towards the target point.
++
++ */
++ /*!
++ \qmlproperty real QtQuick.Particles::TargetDirection::targetX
++ */
++ /*!
++ \qmlproperty real QtQuick.Particles::TargetDirection::targetY
++ */
++ /*!
++ \qmlproperty Item QtQuick.Particles::TargetDirection::targetItem
++ If specified, this will take precedence over targetX and targetY.
++ The targeted point will be the center of the specified Item
++ */
++ /*!
++ \qmlproperty real QtQuick.Particles::TargetDirection::targetVariation
++ */
++ /*!
++ \qmlproperty real QtQuick.Particles::TargetDirection::magnitude
++ */
++ /*!
++ \qmlproperty real QtQuick.Particles::TargetDirection::magnitudeVariation
++ */
++ /*!
++ \qmlproperty bool QtQuick.Particles::TargetDirection::proportionalMagnitude
++
++ If true, then the value of magnitude and magnitudeVariation shall be interpreted as multiples
++ of the distance between the source point and the target point, per second.
++
++ If false(default), then the value of magnitude and magnitudeVariation shall be interpreted as
++ pixels per second.
++ */
++
++ QQuickTargetDirection::QQuickTargetDirection(QObject *parent) :
++ QQuickDirection(parent)
++ , m_targetX(0)
++ , m_targetY(0)
++ , m_targetVariation(0)
++ , m_proportionalMagnitude(false)
++ , m_magnitude(0)
++ , m_magnitudeVariation(0)
++ , m_targetItem(nullptr)
++ {
++ }
++
++ QPointF QQuickTargetDirection::sample(const QPointF &from)
++ {
++ //###This approach loses interpolating the last position of the target (like we could with the emitter) is it worthwhile?
++ QPointF ret;
++ qreal targetX;
++ qreal targetY;
++ if (m_targetItem){
++ QQuickParticleEmitter* parentEmitter = qobject_cast<QQuickParticleEmitter*>(parent());
++ targetX = m_targetItem->width()/2;
++ targetY = m_targetItem->height()/2;
++ if (!parentEmitter){
++ qWarning() << "Directed vector is not a child of the emitter. Mapping of target item coordinates may fail.";
++ targetX += m_targetItem->x();
++ targetY += m_targetItem->y();
++ }else{
++ ret = parentEmitter->mapFromItem(m_targetItem, QPointF(targetX, targetY));
++ targetX = ret.x();
++ targetY = ret.y();
++ }
++ }else{
++ targetX = m_targetX;
++ targetY = m_targetY;
++ }
++ targetX += 0 - from.x() - m_targetVariation + QRandomGenerator::global()->generateDouble() * m_targetVariation*2;
++ targetY += 0 - from.y() - m_targetVariation + QRandomGenerator::global()->generateDouble() * m_targetVariation*2;
++ qreal theta = std::atan2(targetY, targetX);
++ qreal mag = m_magnitude + QRandomGenerator::global()->generateDouble() * m_magnitudeVariation * 2 - m_magnitudeVariation;
++ if (m_proportionalMagnitude)
++ mag *= qHypot(targetX, targetY);
++ ret.setX(mag * std::cos(theta));
++ ret.setY(mag * std::sin(theta));
++ return ret;
++ }
++
++ QT_END_NAMESPACE
++
++ #include "moc_qquicktargetdirection_p.cpp"