source: trunk/examples/animation/easing/animation.h

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** 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 Nokia Corporation and its Subsidiary(-ies) 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 <QtGui>

#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)
    {
        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