cannonfield.cpp

qt-x11-opensource-src-4.1.4.tar.gz源码

/****************************************************************************
**
** Copyright (C) 2005-2006 Trolltech ASA. All rights reserved.
**
** This file is part of the example classes of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 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 GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at [e-mail].
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/

#include <QPaintEvent>
#include <QPainter>

#include "cannonfield.h"

CannonField::CannonField(QWidget *parent)
    : QWidget(parent)
{
    currentAngle = 45;
    currentForce = 0;
    setPalette(QPalette(QColor(250, 250, 200)));
    setAutoFillBackground(true);
}

void CannonField::setAngle(int angle)
{
    if (angle < 5)
        angle = 5;
    if (angle > 70)
        angle = 70;
    if (currentAngle == angle)
        return;
    currentAngle = angle;
    update(cannonRect());
    emit angleChanged(currentAngle);
}

void CannonField::setForce(int force)
{
    if (force < 0)
        force = 0;
    if (currentForce == force)
        return;
    currentForce = force;
    emit forceChanged(currentForce);
}

void CannonField::paintEvent(QPaintEvent * /* event */)
{
    QPainter painter(this);

    painter.setPen(Qt::NoPen);
    painter.setBrush(Qt::blue);

    painter.translate(0, height());
    painter.drawPie(QRect(-35, -35, 70, 70), 0, 90 * 16);
    painter.rotate(-currentAngle);
    painter.drawRect(QRect(30, -5, 20, 10));
}

QRect CannonField::cannonRect() const
{
    QRect result(0, 0, 50, 50);
    result.moveBottomLeft(rect().bottomLeft());
    return result;
}