animation.h Example File

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef ANIMATION_H
#define ANIMATION_H
#include <QtWidgets>
#include <QtCore/qpropertyanimation.h>
class Animation : public QPropertyAnimation {
public:
    enum PathType {
        LinearPath,
        CirclePath,
        NPathTypes
    };
    Animation(QObject *target, const QByteArray &prop)
        : QPropertyAnimation(target, prop)
    {
        setPathType(LinearPath);
    }
    void setPathType(PathType pathType)
    {
        if (pathType >= NPathTypes)
            qWarning("Unknown pathType %d", pathType);
        m_pathType = pathType;
        m_path = QPainterPath();
    }
    void updateCurrentTime(int currentTime) override
    {
        if (m_pathType == CirclePath) {
            if (m_path.isEmpty()) {
                QPointF to = endValue().toPointF();
                QPointF from = startValue().toPointF();
                m_path.moveTo(from);
                m_path.addEllipse(QRectF(from, to));
            }
            int dura = duration();
            const qreal progress = ((dura == 0) ? 1 : ((((currentTime - 1) % dura) + 1) / qreal(dura)));
            qreal easedProgress = easingCurve().valueForProgress(progress);
            if (easedProgress > 1.0) {
                easedProgress -= 1.0;
            } else if (easedProgress < 0) {
                easedProgress += 1.0;
            }
            QPointF pt = m_path.pointAtPercent(easedProgress);
            updateCurrentValue(pt);
            emit valueChanged(pt);
        } else {
            QPropertyAnimation::updateCurrentTime(currentTime);
        }
    }
    QPainterPath m_path;
    PathType m_pathType;
};
#endif // ANIMATION_H