How to change swap intervals for QGLWidget

summit

I am promoting a widet in UI to QGlWidget and in the constructor of QGLWidget i am assigning swap intervals to 0.

But that does not affect the widget it still shows the value of swap interval as 1.

How can i cahnge the swap value to 0.

GLWidget::GLWidget(QWidget *parent) : QGLWidget(parent)
{
QGLFormat format;
format.setDepthBufferSize(24);
format.setStencilBufferSize(8);
format.setSampleBuffers(true);
format.setSamples(4);
format.setSwapInterval(0);
this->setFormat(format);
makeCurrent();

qDebug() << "Swap Interval +++++++++++++++++++++++++++++++++++++++   " << this->format().swapInterval();

}

I am on windows platform.

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
i also tried using QOpenglWidget and still was not able to change the Swap Interval , this is the code for QSurafaceFormat.

int main(int argc, char *argv[])
{
    QSurfaceFormat format;
    format.setDepthBufferSize(8);
    format.setStencilBufferSize(8);

    format.setRedBufferSize(8);
    format.setGreenBufferSize(8);
    format.setBlueBufferSize(8);
    format.setAlphaBufferSize(8);
    format.setSwapInterval(0);  //Turn Vsync on (1) / off (0)
    format.setProfile(QSurfaceFormat::CoreProfile);
    QSurfaceFormat::setDefaultFormat(format);

    //Make sure all OpenGL contexts share resources
    QApplication::setAttribute(Qt::AA_UseDesktopOpenGL);
    QApplication::setAttribute(Qt::AA_ShareOpenGLContexts);

    const QSurfaceFormat& surfaceFormat = QSurfaceFormat::defaultFormat();

    


    QApplication a(argc, argv);
    QtWidgetsApplication2 w;
    w.show();
  
    return a.exec();
}

SGaist

Hi,

Which version of Qt are you using ?
By the way, QGLWidget is deprecated, it is advised to migrate to QOpenGLWidget.

summit

This post is deleted!

summit

@SGaist Hi i am using 5.11 version , i also tried using QOpenGLWidget and changed the QSurafaceFormat swap interval to 0 but still it prints 1 as the value of swap interval.

I have updated the code when using with QOpenGLWidget.

Swap Interval just does not change and when i print the format in InitializeGL() function.
qDebug() << this->format() << " THe format";

I stillGet Swap Interval as 0.

SGaist

Can you check with a more recent version ? 5.11 is outdated.

By the way, which platform are you on ?

summit

@SGaist i am on windows 10 , sure i will try with a newer version.

summit

@SGaist This same issue exists with the version 6.2.