Finding and setting supported opengl version for QOpenGLWidget

gde23

Hello,

i have a ui with a QOpenGLWidget.
On my default machine it runs as it should. However on another machine (with odler graphics card) it just shows a black screen.
I guess because there the maximum opengl version that is supported is 3.1
How can i determine inside Qt which version is supported on a machine and then set the QOpenGLWidget to work with that one?

webzoid

@gde23 I would be interested in finding the solution to this. I also have issues when using QOpenGLWidget on different computers with differing supported OpenGL versions. I've tried various solutions but all of which have not worked.

Jeremy Walker

I have the same question. Surprisingly difficult to find the answer.

JoeCFD

@Jeremy-Walker Try it out to find the version of OpenGL.

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

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

    QOpenGLContext context;
    if ( context.create() ) {
        QSurfaceFormat format = context.format();
        int majorVersion = format.majorVersion();
        int minorVersion = format.minorVersion();

        qDebug() << "Supported OpenGL version: " << majorVersion << "." << minorVersion;
    }
    else {
        qDebug() << "OpenGL creation failed: ";
    }

    return app.exec();
}

JoeCFD

Try to set openGL version:
// Set OpenGL version and profile
QSurfaceFormat format;
format.setVersion(3, 3); // Set OpenGL version (e.g., 3.3)
format.setProfile(QSurfaceFormat::CoreProfile); // Set OpenGL core profile

https://doc.qt.io/qt-5/qopenglwidget.html#setFormat