Russian Qt Forum

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

 GLWidget::GLWidget(Helper *helper, QWidget *parent)
     : QGLWidget(QGLFormat(QGL::SampleBuffers), parent), helper(helper)
 {
     elapsed = 0;
     setFixedSize(200, 200);
     setAutoFillBackground(false);
 }

 void GLWidget::animate()
 {
     elapsed = (elapsed + qobject_cast<QTimer*>(sender())->interval()) % 1000;
     repaint();
 }

 void GLWidget::paintEvent(QPaintEvent *event)
 {
     QPainter painter;
     painter.begin(this);
     painter.setRenderHint(QPainter::Antialiasing);
     helper->paint(&painter, event, elapsed);
     painter.end();
 }

#ifndef GLWIDGET_H
 #define GLWIDGET_H

 #include <QGLWidget>

 class Helper;
 class QPaintEvent;
 class QWidget;

 class GLWidget : public QGLWidget
 {
     Q_OBJECT

 public:
     GLWidget(Helper *helper, QWidget *parent);

 public slots:
     void animate();

 protected:
     void paintEvent(QPaintEvent *event);

 private:
     Helper *helper;
     int elapsed;
 };

 #endif