qtopengltest.pro

#-------------------------------------------------
#
# Project created by QtCreator 2014-02-28T17:28:33
#
#-------------------------------------------------

QT       += core gui opengl openglextensions

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = qtopengltest
TEMPLATE = app


SOURCES += \
    testgl.cpp

HEADERS  += \
    testgl.h

testgl.cpp

#include "testgl.h"

#include <QApplication>
#include <QDebug>
#include <QOpenGLContext>
#include <QSet>

TestGLWidget::TestGLWidget()
  : QGLWidget(QGLFormat(QGL::SampleBuffers))
{
}

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

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

void TestGLWidget::initializeGL()
{
    qglClearColor(QColor(0, 0, 128));

    glShadeModel(GL_SMOOTH);
    glEnable(GL_MULTISAMPLE);

    QOpenGLContext *opengl = QOpenGLContext::currentContext();
    QList<QByteArray> extensions = opengl->extensions().toList();
    qSort(extensions);
    qDebug() << "Supported extensions (" << extensions.count() << ")";
    foreach(const QByteArray &extension, extensions)
        qDebug() << "    " << extension;

    if(opengl->hasExtension(QByteArrayLiteral("GL_ARB_compute_shader")))
    {
        compute_shader = new QOpenGLExtension_ARB_compute_shader();
        compute_shader->initializeOpenGLFunctions();
        //compute_shader->glDispatchCompute();
    }
    else
    {
        qDebug() << "Compute shaders not supported";
        compute_shader = 0;
    }

}

void TestGLWidget::resizeGL(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_1
    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);
}

void TestGLWidget::paintGL()
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glTranslatef(0.0, 0.0, -10.0);
    glBegin(GL_TRIANGLES);
    glVertex3f(-0.2f, -0.2f, 0.0f);
    glVertex3f( 0.2f, -0.2f, 0.0f);
    glVertex3f( 0.2f,  0.2f, 0.0f);
    glEnd();
}

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    setCentralWidget(new TestGLWidget());
    setWindowTitle(tr("Test"));
}

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

testgl.h

#ifndef TESTGL_H
#define TESTGL_H

#include <QGLWidget>
#include <QMainWindow>
#include <QtOpenGLExtensions/QOpenGLExtensions>

class TestGLWidget : public QGLWidget {

    Q_OBJECT

private:
    QOpenGLExtension_ARB_compute_shader *compute_shader;

public:
    TestGLWidget();

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

protected:
    void initializeGL();
    void paintGL();
    void resizeGL(int width, int height);

};

class MainWindow : public QMainWindow {

    Q_OBJECT
    
public:
    MainWindow(QWidget *parent = 0);

};

#endif