/****************************************************************************

**

** All rights reserved.

** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying

** this package.

**

** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include "car.h"

#include <QtGui/QtGui>

#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;

    rotate(rotation);

    translate(0, -speed);

    update();

}