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Tearing occurring in my openGL window when using QOpenGLWidget

  • I have been working on this problem pretty much all day. I have set up a QOpenGLWidget that serves as a simple openGL viewport to render to. Even if I don't draw content, about 50% of the time when I run the app, the screen will flicker like this:

    ! viewport tearing)!

    Other times, it comes up fine. Has anyone ever seen this?

    At first I thought it was my content drawing. So I turned off drawing everything and it still does it about 50% of the time. I'm setting up the QOpenGLWidget like this:

    QSurfaceFormat format;
    format.setProfile( QSurfaceFormat::CoreProfile );


    GLView widget;;

    This is running on a mac.

  • could be graphics driver bug if it doesn't repro on other machines.

  • The heart of this problem turned out to be QOpenGLWidget. When I switched back to QGLWidget, the problem went away. I pretty certain QOpenGLWidget isn't 100% bug free.

    The trouble I have been having is more related to compiling my application to run on Mac and IOS--which use different shaders. The OpenGL surface has to be configured different to accommodate whichever platform is compiling. It doesn't appear that the QOpenGLWidget is compatible with IOS yet

  • in that case, could you please file a Qt bug?

    thank you so much!

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