Qt C++

/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
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** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** 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
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**
** 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.
**
** 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.
**
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****************************************************************************/
#ifndef RENDERAREA_H
#define RENDERAREA_H
#include 
#include 
#include 
#include 
#include 
QT_BEGIN_NAMESPACE
class QPaintEvent;
QT_END_NAMESPACE
enum Operation { NoTransformation, Translate, Rotate, Scale };
class RenderArea : public QWidget
{
    Q_OBJECT
public:
    RenderArea(QWidget *parent = 0);
    void setOperations(const QList &operations);
    void setShape(const QPainterPath &shape);
    QSize minimumSizeHint() const;
    QSize sizeHint() const;
protected:
    void paintEvent(QPaintEvent *event);
private:
    void drawCoordinates(QPainter &painter);
    void drawOutline(QPainter &painter);
    void drawShape(QPainter &painter);
    void transformPainter(QPainter &painter);
    QList operations;
    QPainterPath shape;
    QRect xBoundingRect;
    QRect yBoundingRect;
};
#endif
#include 
#include "renderarea.h"
RenderArea::RenderArea(QWidget *parent)
    : QWidget(parent)
{
    QFont newFont = font();
    newFont.setPixelSize(12);
    setFont(newFont);
    QFontMetrics fontMetrics(newFont);
    xBoundingRect = fontMetrics.boundingRect(tr("x"));
    yBoundingRect = fontMetrics.boundingRect(tr("y"));
}
void RenderArea::setOperations(const QList &operations)
{
    this->operations = operations;
    update();
}
void RenderArea::setShape(const QPainterPath &shape)
{
    this->shape = shape;
    update();
}
QSize RenderArea::minimumSizeHint() const
{
    return QSize(182, 182);
}
QSize RenderArea::sizeHint() const
{
    return QSize(232, 232);
}
void RenderArea::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing);
    painter.fillRect(event->rect(), QBrush(Qt::white));
    painter.translate(66, 66);
    painter.save();
    transformPainter(painter);
    drawShape(painter);
    painter.restore();
    drawOutline(painter);
    transformPainter(painter);
    drawCoordinates(painter);
}
void RenderArea::drawCoordinates(QPainter &painter)
{
    painter.setPen(Qt::red);
    painter.drawLine(0, 0, 50, 0);
    painter.drawLine(48, -2, 50, 0);
    painter.drawLine(48, 2, 50, 0);
    painter.drawText(60 - xBoundingRect.width() / 2,
                     0 + xBoundingRect.height() / 2, tr("x"));
    painter.drawLine(0, 0, 0, 50);
    painter.drawLine(-2, 48, 0, 50);
    painter.drawLine(2, 48, 0, 50);
    painter.drawText(0 - yBoundingRect.width() / 2,
                     60 + yBoundingRect.height() / 2, tr("y"));
}
void RenderArea::drawOutline(QPainter &painter)
{
    painter.setPen(Qt::darkGreen);
    painter.setPen(Qt::DashLine);
    painter.setBrush(Qt::NoBrush);
    painter.drawRect(0, 0, 100, 100);
}
void RenderArea::drawShape(QPainter &painter)
{
    painter.fillPath(shape, Qt::blue);
}
void RenderArea::transformPainter(QPainter &painter)
{
    for (int i = 0; i < operations.size(); ++i) {
        switch (operations[i]) {
        case Translate:
            painter.translate(50, 50);
            break;
        case Scale:
            painter.scale(0.75, 0.75);
            break;
        case Rotate:
            painter.rotate(60);
            break;
        case NoTransformation:
        default:
            ;
        }
    }
}
#ifndef WINDOW_H
#define WINDOW_H
#include 
#include 
#include 
#include "renderarea.h"
QT_BEGIN_NAMESPACE
class QComboBox;
QT_END_NAMESPACE
class Window : public QWidget
{
    Q_OBJECT
public:
    Window();
public slots:
    void operationChanged();
    void shapeSelected(int index);
private:
    void setupShapes();
    enum { NumTransformedAreas = 3 };
    RenderArea *originalRenderArea;
    RenderArea *transformedRenderAreas[NumTransformedAreas];
    QComboBox *shapeComboBox;
    QComboBox *operationComboBoxes[NumTransformedAreas];
    QList shapes;
};
#endif
#include 
#include "window.h"
Window::Window()
{
    originalRenderArea = new RenderArea;
    shapeComboBox = new QComboBox;
    shapeComboBox->addItem(tr("Clock"));
    shapeComboBox->addItem(tr("House"));
    shapeComboBox->addItem(tr("Text"));
    shapeComboBox->addItem(tr("Truck"));
    QGridLayout *layout = new QGridLayout;
    layout->addWidget(originalRenderArea, 0, 0);
    layout->addWidget(shapeComboBox, 1, 0);
    for (int i = 0; i < NumTransformedAreas; ++i) {
        transformedRenderAreas[i] = new RenderArea;
        operationComboBoxes[i] = new QComboBox;
        operationComboBoxes[i]->addItem(tr("No transformation"));
        operationComboBoxes[i]->addItem(tr("Rotate by 60\xB0"));
        operationComboBoxes[i]->addItem(tr("Scale to 75%"));
        operationComboBoxes[i]->addItem(tr("Translate by (50, 50)"));
        connect(operationComboBoxes[i], SIGNAL(activated(int)),
                this, SLOT(operationChanged()));
        layout->addWidget(transformedRenderAreas[i], 0, i + 1);
        layout->addWidget(operationComboBoxes[i], 1, i + 1);
    }
    setLayout(layout);
    setupShapes();
    shapeSelected(0);
    setWindowTitle(tr("Transformations"));
}
void Window::setupShapes()
{
    QPainterPath truck;
    truck.setFillRule(Qt::WindingFill);
    truck.moveTo(0.0, 87.0);
    truck.lineTo(0.0, 60.0);
    truck.lineTo(10.0, 60.0);
    truck.lineTo(35.0, 35.0);
    truck.lineTo(100.0, 35.0);
    truck.lineTo(100.0, 87.0);
    truck.lineTo(0.0, 87.0);
    truck.moveTo(17.0, 60.0);
    truck.lineTo(55.0, 60.0);
    truck.lineTo(55.0, 40.0);
    truck.lineTo(37.0, 40.0);
    truck.lineTo(17.0, 60.0);
    truck.addEllipse(17.0, 75.0, 25.0, 25.0);
    truck.addEllipse(63.0, 75.0, 25.0, 25.0);
    QPainterPath clock;
    clock.addEllipse(-50.0, -50.0, 100.0, 100.0);
    clock.addEllipse(-48.0, -48.0, 96.0, 96.0);
    clock.moveTo(0.0, 0.0);
    clock.lineTo(-2.0, -2.0);
    clock.lineTo(0.0, -42.0);
    clock.lineTo(2.0, -2.0);
    clock.lineTo(0.0, 0.0);
    clock.moveTo(0.0, 0.0);
    clock.lineTo(2.732, -0.732);
    clock.lineTo(24.495, 14.142);
    clock.lineTo(0.732, 2.732);
    clock.lineTo(0.0, 0.0);
    QPainterPath house;
    house.moveTo(-45.0, -20.0);
    house.lineTo(0.0, -45.0);
    house.lineTo(45.0, -20.0);
    house.lineTo(45.0, 45.0);
    house.lineTo(-45.0, 45.0);
    house.lineTo(-45.0, -20.0);
    house.addRect(15.0, 5.0, 20.0, 35.0);
    house.addRect(-35.0, -15.0, 25.0, 25.0);
    QPainterPath text;
    QFont font;
    font.setPixelSize(50);
    QRect fontBoundingRect = QFontMetrics(font).boundingRect(tr("Qt"));
    text.addText(-QPointF(fontBoundingRect.center()), font, tr("Qt"));
    shapes.append(clock);
    shapes.append(house);
    shapes.append(text);
    shapes.append(truck);
    connect(shapeComboBox, SIGNAL(activated(int)),
            this, SLOT(shapeSelected(int)));
}
void Window::operationChanged()
{
    static const Operation operationTable[] = {
        NoTransformation, Rotate, Scale, Translate
    };
    QList operations;
    for (int i = 0; i < NumTransformedAreas; ++i) {
        int index = operationComboBoxes[i]->currentIndex();
        operations.append(operationTable[index]);
        transformedRenderAreas[i]->setOperations(operations);
    }
}
void Window::shapeSelected(int index)
{
    QPainterPath shape = shapes[index];
    originalRenderArea->setShape(shape);
    for (int i = 0; i < NumTransformedAreas; ++i)
        transformedRenderAreas[i]->setShape(shape);
}
#include 
#include "window.h"
int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Window window;
    window.show();
    return app.exec();
}