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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the examples 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 Digia Plc 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."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "car.h"
#include <QtWidgets/QtWidgets>
#include <math.h>
static const double Pi = 3.14159265358979323846264338327950288419717;
QRectF Car::boundingRect() const
{
return QRectF(-35, -81, 70, 115);
}
Car::Car() : color(Qt::green), wheelsAngle(0), speed(0)
{
startTimer(1000 / 33);
setFlag(QGraphicsItem::ItemIsMovable, true);
setFlag(QGraphicsItem::ItemIsFocusable, true);
}
void Car::accelerate()
{
if (speed < 10)
++speed;
}
void Car::decelerate()
{
if (speed > -10)
--speed;
}
void Car::turnLeft()
{
if (wheelsAngle > -30)
wheelsAngle -= 5;
}
void Car::turnRight()
{
if (wheelsAngle < 30)
wheelsAngle += 5;
}
void Car::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
Q_UNUSED(option);
Q_UNUSED(widget);
painter->setBrush(Qt::gray);
painter->drawRect(-20, -58, 40, 2); // front axel
painter->drawRect(-20, 7, 40, 2); // rear axel
painter->setBrush(color);
painter->drawRect(-25, -79, 50, 10); // front wing
painter->drawEllipse(-25, -48, 50, 20); // side pods
painter->drawRect(-25, -38, 50, 35); // side pods
painter->drawRect(-5, 9, 10, 10); // back pod
painter->drawEllipse(-10, -81, 20, 100); // main body
painter->drawRect(-17, 19, 34, 15); // rear wing
painter->setBrush(Qt::black);
painter->drawPie(-5, -51, 10, 15, 0, 180 * 16);
painter->drawRect(-5, -44, 10, 10); // cocpit
painter->save();
painter->translate(-20, -58);
painter->rotate(wheelsAngle);
painter->drawRect(-10, -7, 10, 15); // front left
painter->restore();
painter->save();
painter->translate(20, -58);
painter->rotate(wheelsAngle);
painter->drawRect(0, -7, 10, 15); // front left
painter->restore();
painter->drawRect(-30, 0, 12, 17); // rear left
painter->drawRect(19, 0, 12, 17); // rear right
}
void Car::timerEvent(QTimerEvent *event)
{
Q_UNUSED(event);
const qreal axelDistance = 54;
qreal wheelsAngleRads = (wheelsAngle * Pi) / 180;
qreal turnDistance = ::cos(wheelsAngleRads) * axelDistance * 2;
qreal turnRateRads = wheelsAngleRads / turnDistance; // rough estimate
qreal turnRate = (turnRateRads * 180) / Pi;
qreal rotation = speed * turnRate;
setTransform(QTransform().rotate(rotation), true);
setTransform(QTransform::fromTranslate(0, -speed), true);
update();
}
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