qtbase/examples/opengl/hellogles3/main.cpp

// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include <QGuiApplication>
#include <QSurfaceFormat>
#include <QOpenGLContext>

#include "glwindow.h"

// This example demonstrates easy, cross-platform usage of OpenGL ES 3.0 functions via
// QOpenGLExtraFunctions in an application that works identically on desktop platforms
// with OpenGL 3.3 and mobile/embedded devices with OpenGL ES 3.0.

// The code is always the same, with the exception of two places: (1) the OpenGL context
// creation has to have a sufficiently high version number for the features that are in
// use, and (2) the shader code's version directive is different.

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    QSurfaceFormat fmt;
    fmt.setDepthBufferSize(24);

    // Request OpenGL 3.3 core or OpenGL ES 3.0.
    if (QOpenGLContext::openGLModuleType() == QOpenGLContext::LibGL) {
        qDebug("Requesting 3.3 core context");
        fmt.setVersion(3, 3);
        fmt.setProfile(QSurfaceFormat::CoreProfile);
    } else {
        qDebug("Requesting 3.0 context");
        fmt.setVersion(3, 0);
    }

    QSurfaceFormat::setDefaultFormat(fmt);

    GLWindow glWindow;
    glWindow.showMaximized();

    return app.exec();
}