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QT 5.4 OpenGL aliasing problem

  • What QSurfaceFormat setting do I need to set to prevent aliasing?

    Currently I'm using:

    fmt.setRenderableType( QSurfaceFormat::OpenGL );

  • I certainly notice a difference in my apps between fmt.setSamples(1) and fmt.setSamples(16), at least for whether polygon edges appear "jaggy" or not. What GPU HW are you using? Got screenshots?

  • How do I post a screen shot?

    Another name for the problems maybe Z fighting.

    GPU HW is Quadro 5000.

  • Z-fighting is a completely different issue from aliasing. Maybe you need to set/check/increase the QSurfaceFormat::depthSize property (I've no idea what the default is).

    If your z-buffer precision is as good as it can be, glPolygonOffset and/or controlling draw-order are next lines of defence against z-fighting.

    I seem to remember the old forum allowed image upload; but maybe I'm thinking of the Jira (bugtracker). The markdown formatting here would let you link to a URL hosted elsewhere though (and maybe include it inline).