qquickpathinterpolator.cpp

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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
// Qt-Security score:significant reason:default
 
#include "qquickpathinterpolator_p.h"
 
#include "qquickpath_p.h"
 
QT_BEGIN_NAMESPACE
 
/*!
    \qmltype PathInterpolator
    \nativetype QQuickPathInterpolator
    \inqmlmodule QtQuick
    \ingroup qtquick-animation-control
    \brief Specifies how to manually animate along a path.
 
    PathInterpolator provides \c x, \c y, and \c angle information for a particular \c progress
    along a path.
 
    In the following example, we animate a green rectangle along a bezier path.
 
    \snippet qml/pathinterpolator.qml 0
*/
 
QQuickPathInterpolator::QQuickPathInterpolator(QObject *parent) :
    QObject(parent), _path(nullptr), _x(0), _y(0), _angle(0), _progress(0)
{
}
 
/*!
    \qmlproperty Path QtQuick::PathInterpolator::path
    This property holds the path to interpolate.
 
    For more information on defining a path see the \l Path documentation.
*/
QQuickPath *QQuickPathInterpolator::path() const
{
    return _path;
}
 
void QQuickPathInterpolator::setPath(QQuickPath *path)
{
    if (_path == path)
        return;
    if (_path)
        disconnect(_path, SIGNAL(changed()), this, SLOT(_q_pathUpdated()));
    _path = path;
    connect(_path, SIGNAL(changed()), this, SLOT(_q_pathUpdated()));
    emit pathChanged();
}
 
/*!
    \qmlproperty real QtQuick::PathInterpolator::progress
    This property holds the current progress along the path.
 
    Typical usage of PathInterpolator is to set the progress
    (often via a NumberAnimation), and read the corresponding
    values for x, y, and angle (often via bindings to these values).
 
    Progress ranges from 0.0 to 1.0.
*/
qreal QQuickPathInterpolator::progress() const
{
    return _progress;
}
 
void QQuickPathInterpolator::setProgress(qreal progress)
{
    progress = qMin(qMax(progress, (qreal)0.0), (qreal)1.0);
 
    if (progress == _progress)
        return;
    _progress = progress;
    emit progressChanged();
    _q_pathUpdated();
}
 
/*!
    \qmlproperty real QtQuick::PathInterpolator::x
    \qmlproperty real QtQuick::PathInterpolator::y
 
    These properties hold the position of the path at \l progress.
*/
qreal QQuickPathInterpolator::x() const
{
    return _x;
}
 
qreal QQuickPathInterpolator::y() const
{
    return _y;
}
 
/*!
    \qmlproperty real QtQuick::PathInterpolator::angle
 
    This property holds the angle of the path tangent at \l progress.
 
    Angles are reported clockwise, with zero degrees at the 3 o'clock position.
*/
qreal QQuickPathInterpolator::angle() const
{
    return _angle;
}
 
void QQuickPathInterpolator::_q_pathUpdated()
{
    if (! _path)
        return;
 
    qreal angle = 0;
    const QPointF pt = _path->sequentialPointAt(_progress, &angle);
 
    if (_x != pt.x()) {
        _x = pt.x();
        emit xChanged();
    }
 
    if (_y != pt.y()) {
        _y = pt.y();
        emit yChanged();
    }
 
    //convert to clockwise
    angle = qreal(360) - angle;
    if (qFuzzyCompare(angle, qreal(360)))
        angle = qreal(0);
 
    if (angle != _angle) {
        _angle = angle;
        emit angleChanged();
    }
}
 
QT_END_NAMESPACE
 
#include "moc_qquickpathinterpolator_p.cpp"