/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Qt Software Information (qt-info@nokia.com)
**
** This file is part of the examples 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 either Technology Preview License Agreement or the
** Beta Release License Agreement.
**
** 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 1.0, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you are unsure which license is appropriate for your use, please
** contact the sales department at qt-sales@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QtGui>

#include "circlewidget.h"

#include <stdlib.h>

//! [0]
CircleWidget::CircleWidget(QWidget *parent)
    : QWidget(parent)
{
    floatBased = false;
    antialiased = false;
    frameNo = 0;

    setBackgroundRole(QPalette::Base);
    setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
}
//! [0]

//! [1]
void CircleWidget::setFloatBased(bool floatBased)
{
    this->floatBased = floatBased;
    update();
}
//! [1]

//! [2]
void CircleWidget::setAntialiased(bool antialiased)
{
    this->antialiased = antialiased;
    update();
}
//! [2]

//! [3]
QSize CircleWidget::minimumSizeHint() const
{
    return QSize(50, 50);
}
//! [3]

//! [4]
QSize CircleWidget::sizeHint() const
{
    return QSize(180, 180);
}
//! [4]

//! [5]
void CircleWidget::nextAnimationFrame()
{
    ++frameNo;
    update();
}
//! [5]

//! [6]
void CircleWidget::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing, antialiased);
    painter.translate(width() / 2, height() / 2);
//! [6]

//! [7]
    for (int diameter = 0; diameter < 256; diameter += 9) {
        int delta = abs((frameNo % 128) - diameter / 2);
        int alpha = 255 - (delta * delta) / 4 - diameter;
//! [7] //! [8]
        if (alpha > 0) {
            painter.setPen(QPen(QColor(0, diameter / 2, 127, alpha), 3));

            if (floatBased) {
                painter.drawEllipse(QRectF(-diameter / 2.0, -diameter / 2.0,
                                           diameter, diameter));
            } else {
                painter.drawEllipse(QRect(-diameter / 2, -diameter / 2,
                                          diameter, diameter));
            }
        }
    }
}
//! [8]