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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "car.h"
#include <QtWidgets/QtWidgets>
#include <qmath.h>
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 = qDegreesToRadians(wheelsAngle);
qreal turnDistance = ::cos(wheelsAngleRads) * axelDistance * 2;
qreal turnRateRads = wheelsAngleRads / turnDistance; // rough estimate
qreal turnRate = qRadiansToDegrees(turnRateRads);
qreal rotation = speed * turnRate;
setTransform(QTransform().rotate(rotation), true);
setTransform(QTransform::fromTranslate(0, -speed), true);
update();
}
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