Qt Opengl Splash Screen

glwidget.h

#ifndef GLWIDGET_H
#define GLWIDGET_H

#include <QGLWidget>

class GLWidget : public QGLWidget
{
   Q_OBJECT

public:
   GLWidget(QWidget *parent = 0);
   ~GLWidget();

   QSize minimumSizeHint() const;
   QSize sizeHint() const;

public slots:
   void setXRotation(int angle);
   void setYRotation(int angle);
   void setZRotation(int angle);

signals:
   void xRotationChanged(int angle);
   void yRotationChanged(int angle);
   void zRotationChanged(int angle);

protected:
   void initializeGL();
   void paintGL();
   void resizeGL(int width, int height);
   void mousePressEvent(QMouseEvent *event);
   void mouseMoveEvent(QMouseEvent *event);

private:
   GLuint makeObject();
   void quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
             GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4);
   void extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2);
   void normalizeAngle(int *angle);

   GLuint object;
   int xRot;
   int yRot;
   int zRot;
   QPoint lastPos;
   QColor trolltechGreen;
   QColor trolltechPurple;
};

#endif

glwidget.cpp

#include <QtGui>
#include <math.h>
#include "glwidget.h"

GLWidget::GLWidget(QWidget *parent)
   : QGLWidget(parent)
{
   object = 0;
   xRot = 300;
   yRot = 0;
   zRot = 0;

   trolltechGreen = QColor::fromCmykF(0.40, 0.0, 1.0, 0.0);
   trolltechPurple = QColor::fromCmykF(0.39, 0.39, 0.0, 0.0);
}

GLWidget::~GLWidget()
{
   makeCurrent();
   glDeleteLists(object, 1);
}

QSize GLWidget::minimumSizeHint() const
{
   return QSize(50, 50);
}

QSize GLWidget::sizeHint() const
{
   return QSize(400, 400);
}

void GLWidget::setXRotation(int angle)
{
   normalizeAngle(&angle);
   if (angle != xRot) {
       xRot = angle;
       emit xRotationChanged(angle);
       updateGL();
   }
}

void GLWidget::setYRotation(int angle)
{
   normalizeAngle(&angle);
   if (angle != yRot) {
       yRot = angle;
       emit yRotationChanged(angle);
       updateGL();
   }
}

void GLWidget::setZRotation(int angle)
{
   normalizeAngle(&angle);
   if (angle != zRot) {
       zRot = angle;
       emit zRotationChanged(angle);
       updateGL();
   }
}

void GLWidget::initializeGL()
{
   qglClearColor(trolltechPurple.dark());
   object = makeObject();
   glShadeModel(GL_FLAT);
   glEnable(GL_DEPTH_TEST);
   glEnable(GL_CULL_FACE);
}

void GLWidget::paintGL()
{
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
   glLoadIdentity();
   glTranslated(0.0, 0.0, -10.0);
   glRotated(xRot / 16.0, 1.0, 0.0, 0.0);
   glRotated(yRot / 16.0, 0.0, 1.0, 0.0);
   glRotated(zRot / 16.0, 0.0, 0.0, 1.0);
   glCallList(object);
}

void GLWidget::resizeGL(int width, int height)
{
   int side = qMin(width, height);
   glViewport((width - side) / 2, (height - side) / 2, side, side);

   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
   glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0);
   glMatrixMode(GL_MODELVIEW);
}

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();
}

GLuint GLWidget::makeObject()
{
   GLuint list = glGenLists(1);
   glNewList(list, GL_COMPILE);

   glBegin(GL_QUADS);

   GLdouble x1 = +0.06;
   GLdouble y1 = -0.14;
   GLdouble x2 = +0.14;
   GLdouble y2 = -0.06;
   GLdouble x3 = +0.08;
   GLdouble y3 = +0.00;
   GLdouble x4 = +0.30;
   GLdouble y4 = +0.22;

   quad(x1, y1, x2, y2, y2, x2, y1, x1);
   quad(x3, y3, x4, y4, y4, x4, y3, x3);

   extrude(x1, y1, x2, y2);
   extrude(x2, y2, y2, x2);
   extrude(y2, x2, y1, x1);
   extrude(y1, x1, x1, y1);
   extrude(x3, y3, x4, y4);
   extrude(x4, y4, y4, x4);
   extrude(y4, x4, y3, x3);

   const double Pi = 3.14159265358979323846;
   const int NumSectors = 200;

   for (int i = 0; i < NumSectors; ++i) {
       double angle1 = (i * 2 * Pi) / NumSectors;
       GLdouble x5 = 0.30 * sin(angle1);
       GLdouble y5 = 0.30 * cos(angle1);
       GLdouble x6 = 0.20 * sin(angle1);
       GLdouble y6 = 0.20 * cos(angle1);

       double angle2 = ((i + 1) * 2 * Pi) / NumSectors;
       GLdouble x7 = 0.20 * sin(angle2);
       GLdouble y7 = 0.20 * cos(angle2);
       GLdouble x8 = 0.30 * sin(angle2);
       GLdouble y8 = 0.30 * cos(angle2);

       quad(x5, y5, x6, y6, x7, y7, x8, y8);

       extrude(x6, y6, x7, y7);
       extrude(x8, y8, x5, y5);
   }

   glEnd();

   glEndList();
   return list;
}

void GLWidget::quad(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2,
                   GLdouble x3, GLdouble y3, GLdouble x4, GLdouble y4)
{
   qglColor(trolltechGreen);

   glVertex3d(x1, y1, -0.05);
   glVertex3d(x2, y2, -0.05);
   glVertex3d(x3, y3, -0.05);
   glVertex3d(x4, y4, -0.05);

   glVertex3d(x4, y4, +0.05);
   glVertex3d(x3, y3, +0.05);
   glVertex3d(x2, y2, +0.05);
   glVertex3d(x1, y1, +0.05);
}

void GLWidget::extrude(GLdouble x1, GLdouble y1, GLdouble x2, GLdouble y2)
{
   qglColor(trolltechGreen.dark(250 + int(100 * x1)));

   glVertex3d(x1, y1, +0.05);
   glVertex3d(x2, y2, +0.05);
   glVertex3d(x2, y2, -0.05);
   glVertex3d(x1, y1, -0.05);
}

void GLWidget::normalizeAngle(int *angle)
{
   while (*angle < 0)
       *angle += 360 * 16;
   while (*angle > 360 * 16)
       *angle -= 360 * 16;
}

dialog.h

#ifndef DIALOG_H
#define DIALOG_H

#include <QtGui/QDialog>
#include "glwidget.h"
class Dialog : public QDialog
{
    Q_OBJECT

public:
    Dialog(QWidget *parent = 0);
    ~Dialog();
private:
    GLWidget *w;
};

#endif // DIALOG_H

dialog.cpp

#include "dialog.h"
#include <QRegion>
Dialog::Dialog(QWidget *parent)
    : QDialog(parent)
{
    w=new GLWidget(this);
    setWindowFlags(Qt::SplashScreen);

    w->setGeometry(0,0,600,600);

    setMask(QRegion(0, 0, 600, 600,
                        QRegion::Ellipse));
}

Dialog::~Dialog()
{

}

main.cpp

#include <QtGui/QApplication>
#include "dialog.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Dialog w;
    w.show();
    return a.exec();
}

# -------------------------------------------------
# Project created by QtCreator 2009-04-02T12:03:32
# -------------------------------------------------
QT += opengl
TARGET = gl
TEMPLATE = app
SOURCES += main.cpp \
dialog.cpp \
glwidget.cpp
HEADERS += dialog.h \
glwidget.h