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     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the examples of the Qt Toolkit.

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     9 ** $QT_BEGIN_LICENSE:LGPL$

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    12 ** You may use this file in accordance with the terms and conditions

    13 ** contained in the Technology Preview License Agreement accompanying

    14 ** this package.

    15 **

    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

    19 ** Foundation and appearing in the file LICENSE.LGPL included in the

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    21 ** ensure the GNU Lesser General Public License version 2.1 requirements

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    24 ** In addition, as a special exception, Nokia gives you certain additional

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    36 **

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    38 ** $QT_END_LICENSE$

    39 **

    40 ****************************************************************************/

    41 

    42 #include <QtGui>

    43 #include <QtOpenGL>

    44 #include <stdlib.h>

    45 

    46 #include <math.h>

    47 

    48 #include "bubble.h"

    49 #include "qtlogo.h"

    50 #include "glwidget.h"

    51 

    52 #ifndef GL_MULTISAMPLE

    53 #define GL_MULTISAMPLE  0x809D

    54 #endif

    55 

    56 //! [0]

    57 GLWidget::GLWidget(QWidget *parent)

    58     : QGLWidget(QGLFormat(QGL::SampleBuffers), parent)

    59 {

    60     QTime midnight(0, 0, 0);

    61     qsrand(midnight.secsTo(QTime::currentTime()));

    62 

    63     logo = 0;

    64     xRot = 0;

    65     yRot = 0;

    66     zRot = 0;

    67 

    68     qtGreen = QColor::fromCmykF(0.40, 0.0, 1.0, 0.0);

    69     qtPurple = QColor::fromCmykF(0.39, 0.39, 0.0, 0.0);

    70 

    71     animationTimer.setSingleShot(false);

    72     connect(&animationTimer, SIGNAL(timeout()), this, SLOT(animate()));

    73     animationTimer.start(25);

    74 

    75     setAutoFillBackground(false);

    76     setMinimumSize(200, 200);

    77     setWindowTitle(tr("Overpainting a Scene"));

    78 }

    79 //! [0]

    80 

    81 //! [1]

    82 GLWidget::~GLWidget()

    83 {

    84 }

    85 //! [1]

    86 

    87 static void qNormalizeAngle(int &angle)

    88 {

    89     while (angle < 0)

    90         angle += 360 * 16;

    91     while (angle > 360 * 16)

    92         angle -= 360 * 16;

    93 }

    94 

    95 void GLWidget::setXRotation(int angle)

    96 {

    97     qNormalizeAngle(angle);

    98     if (angle != xRot)

    99         xRot = angle;

   100 }

   101 

   102 void GLWidget::setYRotation(int angle)

   103 {

   104     qNormalizeAngle(angle);

   105     if (angle != yRot)

   106         yRot = angle;

   107 }

   108 

   109 void GLWidget::setZRotation(int angle)

   110 {

   111     qNormalizeAngle(angle);

   112     if (angle != zRot)

   113         zRot = angle;

   114 }

   115 

   116 //! [2]

   117 void GLWidget::initializeGL()

   118 {

   119     glEnable(GL_MULTISAMPLE);

   120 

   121     logo = new QtLogo(this);

   122     logo->setColor(qtGreen.dark());

   123 }

   124 //! [2]

   125 

   126 void GLWidget::mousePressEvent(QMouseEvent *event)

   127 {

   128     lastPos = event->pos();

   129 }

   130 

   131 void GLWidget::mouseMoveEvent(QMouseEvent *event)

   132 {

   133     int dx = event->x() - lastPos.x();

   134     int dy = event->y() - lastPos.y();

   135 

   136     if (event->buttons() & Qt::LeftButton) {

   137         setXRotation(xRot + 8 * dy);

   138         setYRotation(yRot + 8 * dx);

   139     } else if (event->buttons() & Qt::RightButton) {

   140         setXRotation(xRot + 8 * dy);

   141         setZRotation(zRot + 8 * dx);

   142     }

   143     lastPos = event->pos();

   144 }

   145 

   146 void GLWidget::paintEvent(QPaintEvent *event)

   147 {

   148     makeCurrent();

   149 //! [4]

   150     glMatrixMode(GL_MODELVIEW);

   151     glPushMatrix();

   152 //! [4]

   153 

   154 //! [6]

   155     qglClearColor(qtPurple.dark());

   156     glShadeModel(GL_SMOOTH);

   157     glEnable(GL_DEPTH_TEST);

   158     glEnable(GL_CULL_FACE);

   159     glEnable(GL_LIGHTING);

   160     glEnable(GL_LIGHT0);

   161     glEnable(GL_MULTISAMPLE);

   162     static GLfloat lightPosition[4] = { 0.5, 5.0, 7.0, 1.0 };

   163     glLightfv(GL_LIGHT0, GL_POSITION, lightPosition);

   164 

   165     setupViewport(width(), height());

   166 //! [6]

   167 

   168 //! [7]

   169     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

   170     glLoadIdentity();

   171     glTranslatef(0.0, 0.0, -10.0);

   172     glRotatef(xRot / 16.0, 1.0, 0.0, 0.0);

   173     glRotatef(yRot / 16.0, 0.0, 1.0, 0.0);

   174     glRotatef(zRot / 16.0, 0.0, 0.0, 1.0);

   175 

   176     logo->draw();

   177 //! [7]

   178 

   179 //! [8]

   180     glShadeModel(GL_FLAT);

   181     glDisable(GL_CULL_FACE);

   182     glDisable(GL_DEPTH_TEST);

   183     glDisable(GL_LIGHTING);

   184 

   185     glMatrixMode(GL_MODELVIEW);

   186     glPopMatrix();

   187 //! [8]

   188 

   189 //! [10]

   190     QPainter painter(this);

   191     painter.setRenderHint(QPainter::Antialiasing);

   192     foreach (Bubble *bubble, bubbles) {

   193         if (bubble->rect().intersects(event->rect()))

   194             bubble->drawBubble(&painter);

   195     }

   196     drawInstructions(&painter);

   197     painter.end();

   198 }

   199 //! [10]

   200 

   201 //! [11]

   202 void GLWidget::resizeGL(int width, int height)

   203 {

   204     setupViewport(width, height);

   205 }

   206 //! [11]

   207 

   208 //! [12]

   209 void GLWidget::showEvent(QShowEvent *event)

   210 {

   211     Q_UNUSED(event);

   212     createBubbles(20 - bubbles.count());

   213 }

   214 //! [12]

   215 

   216 QSize GLWidget::sizeHint() const

   217 {

   218     return QSize(400, 400);

   219 }

   220 

   221 void GLWidget::createBubbles(int number)

   222 {

   223     for (int i = 0; i < number; ++i) {

   224         QPointF position(width()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))),

   225                         height()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))));

   226         qreal radius = qMin(width(), height())*(0.0125 + 0.0875*qrand()/(RAND_MAX+1.0));

   227         QPointF velocity(width()*0.0125*(-0.5 + qrand()/(RAND_MAX+1.0)),

   228                         height()*0.0125*(-0.5 + qrand()/(RAND_MAX+1.0)));

   229 

   230         bubbles.append(new Bubble(position, radius, velocity));

   231     }

   232 }

   233 

   234 //! [13]

   235 void GLWidget::animate()

   236 {

   237     QMutableListIterator<Bubble*> iter(bubbles);

   238 

   239     while (iter.hasNext()) {

   240         Bubble *bubble = iter.next();

   241         bubble->move(rect());

   242     }

   243     update();

   244 }

   245 //! [13]

   246 

   247 //! [14]

   248 void GLWidget::setupViewport(int width, int height)

   249 {

   250     int side = qMin(width, height);

   251     glViewport((width - side) / 2, (height - side) / 2, side, side);

   252 

   253     glMatrixMode(GL_PROJECTION);

   254     glLoadIdentity();

   255 #ifdef QT_OPENGL_ES

   256     glOrthof(-0.5, +0.5, -0.5, 0.5, 4.0, 15.0);

   257 #else

   258     glOrtho(-0.5, +0.5, -0.5, 0.5, 4.0, 15.0);

   259 #endif

   260     glMatrixMode(GL_MODELVIEW);

   261 }

   262 //! [14]

   263 

   264 //! [15]

   265 void GLWidget::drawInstructions(QPainter *painter)

   266 {

   267     QString text = tr("Click and drag with the left mouse button "

   268                       "to rotate the Qt logo.");

   269     QFontMetrics metrics = QFontMetrics(font());

   270     int border = qMax(4, metrics.leading());

   271 

   272     QRect rect = metrics.boundingRect(0, 0, width() - 2*border, int(height()*0.125),

   273                                       Qt::AlignCenter | Qt::TextWordWrap, text);

   274     painter->setRenderHint(QPainter::TextAntialiasing);

   275     painter->fillRect(QRect(0, 0, width(), rect.height() + 2*border),

   276                      QColor(0, 0, 0, 127));

   277     painter->setPen(Qt::white);

   278     painter->fillRect(QRect(0, 0, width(), rect.height() + 2*border),

   279                       QColor(0, 0, 0, 127));

   280     painter->drawText((width() - rect.width())/2, border,

   281                       rect.width(), rect.height(),

   282                       Qt::AlignCenter | Qt::TextWordWrap, text);

   283 }

   284 //! [15]