examples/opengl/overpainting/glwidget.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/opengl/overpainting/glwidget.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,284 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 <QtGui>
+#include <QtOpenGL>
+#include <stdlib.h>
+
+#include <math.h>
+
+#include "bubble.h"
+#include "qtlogo.h"
+#include "glwidget.h"
+
+#ifndef GL_MULTISAMPLE
+#define GL_MULTISAMPLE  0x809D
+#endif
+
+//! [0]
+GLWidget::GLWidget(QWidget *parent)
+    : QGLWidget(QGLFormat(QGL::SampleBuffers), parent)
+{
+    QTime midnight(0, 0, 0);
+    qsrand(midnight.secsTo(QTime::currentTime()));
+
+    logo = 0;
+    xRot = 0;
+    yRot = 0;
+    zRot = 0;
+
+    qtGreen = QColor::fromCmykF(0.40, 0.0, 1.0, 0.0);
+    qtPurple = QColor::fromCmykF(0.39, 0.39, 0.0, 0.0);
+
+    animationTimer.setSingleShot(false);
+    connect(&animationTimer, SIGNAL(timeout()), this, SLOT(animate()));
+    animationTimer.start(25);
+
+    setAutoFillBackground(false);
+    setMinimumSize(200, 200);
+    setWindowTitle(tr("Overpainting a Scene"));
+}
+//! [0]
+
+//! [1]
+GLWidget::~GLWidget()
+{
+}
+//! [1]
+
+static void qNormalizeAngle(int &angle)
+{
+    while (angle < 0)
+        angle += 360 * 16;
+    while (angle > 360 * 16)
+        angle -= 360 * 16;
+}
+
+void GLWidget::setXRotation(int angle)
+{
+    qNormalizeAngle(angle);
+    if (angle != xRot)
+        xRot = angle;
+}
+
+void GLWidget::setYRotation(int angle)
+{
+    qNormalizeAngle(angle);
+    if (angle != yRot)
+        yRot = angle;
+}
+
+void GLWidget::setZRotation(int angle)
+{
+    qNormalizeAngle(angle);
+    if (angle != zRot)
+        zRot = angle;
+}
+
+//! [2]
+void GLWidget::initializeGL()
+{
+    glEnable(GL_MULTISAMPLE);
+
+    logo = new QtLogo(this);
+    logo->setColor(qtGreen.dark());
+}
+//! [2]
+
+void GLWidget::mousePressEvent(QMouseEvent *event)
+{
+    lastPos = event->pos();
+}
+
+void GLWidget::mouseMoveEvent(QMouseEvent *event)
+{
+    int dx = event->x() - lastPos.x();
+    int dy = event->y() - lastPos.y();
+
+    if (event->buttons() & Qt::LeftButton) {
+        setXRotation(xRot + 8 * dy);
+        setYRotation(yRot + 8 * dx);
+    } else if (event->buttons() & Qt::RightButton) {
+        setXRotation(xRot + 8 * dy);
+        setZRotation(zRot + 8 * dx);
+    }
+    lastPos = event->pos();
+}
+
+void GLWidget::paintEvent(QPaintEvent *event)
+{
+    makeCurrent();
+//! [4]
+    glMatrixMode(GL_MODELVIEW);
+    glPushMatrix();
+//! [4]
+
+//! [6]
+    qglClearColor(qtPurple.dark());
+    glShadeModel(GL_SMOOTH);
+    glEnable(GL_DEPTH_TEST);
+    glEnable(GL_CULL_FACE);
+    glEnable(GL_LIGHTING);
+    glEnable(GL_LIGHT0);
+    glEnable(GL_MULTISAMPLE);
+    static GLfloat lightPosition[4] = { 0.5, 5.0, 7.0, 1.0 };
+    glLightfv(GL_LIGHT0, GL_POSITION, lightPosition);
+
+    setupViewport(width(), height());
+//! [6]
+
+//! [7]
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glLoadIdentity();
+    glTranslatef(0.0, 0.0, -10.0);
+    glRotatef(xRot / 16.0, 1.0, 0.0, 0.0);
+    glRotatef(yRot / 16.0, 0.0, 1.0, 0.0);
+    glRotatef(zRot / 16.0, 0.0, 0.0, 1.0);
+
+    logo->draw();
+//! [7]
+
+//! [8]
+    glShadeModel(GL_FLAT);
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glDisable(GL_LIGHTING);
+
+    glMatrixMode(GL_MODELVIEW);
+    glPopMatrix();
+//! [8]
+
+//! [10]
+    QPainter painter(this);
+    painter.setRenderHint(QPainter::Antialiasing);
+    foreach (Bubble *bubble, bubbles) {
+        if (bubble->rect().intersects(event->rect()))
+            bubble->drawBubble(&painter);
+    }
+    drawInstructions(&painter);
+    painter.end();
+}
+//! [10]
+
+//! [11]
+void GLWidget::resizeGL(int width, int height)
+{
+    setupViewport(width, height);
+}
+//! [11]
+
+//! [12]
+void GLWidget::showEvent(QShowEvent *event)
+{
+    Q_UNUSED(event);
+    createBubbles(20 - bubbles.count());
+}
+//! [12]
+
+QSize GLWidget::sizeHint() const
+{
+    return QSize(400, 400);
+}
+
+void GLWidget::createBubbles(int number)
+{
+    for (int i = 0; i < number; ++i) {
+        QPointF position(width()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))),
+                        height()*(0.1 + (0.8*qrand()/(RAND_MAX+1.0))));
+        qreal radius = qMin(width(), height())*(0.0125 + 0.0875*qrand()/(RAND_MAX+1.0));
+        QPointF velocity(width()*0.0125*(-0.5 + qrand()/(RAND_MAX+1.0)),
+                        height()*0.0125*(-0.5 + qrand()/(RAND_MAX+1.0)));
+
+        bubbles.append(new Bubble(position, radius, velocity));
+    }
+}
+
+//! [13]
+void GLWidget::animate()
+{
+    QMutableListIterator<Bubble*> iter(bubbles);
+
+    while (iter.hasNext()) {
+        Bubble *bubble = iter.next();
+        bubble->move(rect());
+    }
+    update();
+}
+//! [13]
+
+//! [14]
+void GLWidget::setupViewport(int width, int height)
+{
+    int side = qMin(width, height);
+    glViewport((width - side) / 2, (height - side) / 2, side, side);
+
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+#ifdef QT_OPENGL_ES
+    glOrthof(-0.5, +0.5, -0.5, 0.5, 4.0, 15.0);
+#else
+    glOrtho(-0.5, +0.5, -0.5, 0.5, 4.0, 15.0);
+#endif
+    glMatrixMode(GL_MODELVIEW);
+}
+//! [14]
+
+//! [15]
+void GLWidget::drawInstructions(QPainter *painter)
+{
+    QString text = tr("Click and drag with the left mouse button "
+                      "to rotate the Qt logo.");
+    QFontMetrics metrics = QFontMetrics(font());
+    int border = qMax(4, metrics.leading());
+
+    QRect rect = metrics.boundingRect(0, 0, width() - 2*border, int(height()*0.125),
+                                      Qt::AlignCenter | Qt::TextWordWrap, text);
+    painter->setRenderHint(QPainter::TextAntialiasing);
+    painter->fillRect(QRect(0, 0, width(), rect.height() + 2*border),
+                     QColor(0, 0, 0, 127));
+    painter->setPen(Qt::white);
+    painter->fillRect(QRect(0, 0, width(), rect.height() + 2*border),
+                      QColor(0, 0, 0, 127));
+    painter->drawText((width() - rect.width())/2, border,
+                      rect.width(), rect.height(),
+                      Qt::AlignCenter | Qt::TextWordWrap, text);
+}
+//! [15]