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Qt 5.9, OpenGL, mesa libraries - black screen

  • Hello everybody,

    I have finally successfully compiled a Qt app (C++) using OpenGL on a CentOS 7 machine. The application was originally developed for Windows.

    I have an OpenGL scene that is showing a black screen. It works if I compile the project with the Windows version of Qt in a Windows environment.

    All controls and functionalities are working except I cannot see the result on the OpenGL scene.

    I am using the Mesa libraries on a CentOS system:

    glxinfo | grep vendor
    server glx vendor string: SGI
    client glx vendor string: Mesa Project and SGI
    OpenGL vendor string: VMware, Inc.

    and I can see the that 3D acceleration is on:

    glxinfo | grep rendering
    direct rendering: Yes

    Any idea?

    Thank you for your help,


  • Lifetime Qt Champion

    Can you run glgears or any other openGL app ?

    Have you tried outside of virtual machine?

  • Hi mrjj,

    the glxgears works:

    [dcappiello@localhost ~]$ glxgears
    2423 frames in 5.0 seconds = 484.186 FPS
    2579 frames in 5.0 seconds = 515.722 FPS
    2718 frames in 5.0 seconds = 543.542 FPS
    2176 frames in 5.0 seconds = 435.088 FPS

  • Lifetime Qt Champion

    Ok so at least some openGL is available
    Maybe its the shader revision.

    Do you run it in Creator or outside ?

    Also does the
    OpenGL Window Example
    run ?

  • I am running my project inside the Creator.

    I can confirm that the OpenGL Window Example is not working, I am getting the following error:

    Project ERROR: Unknown module(s) in QT: axserver

    You are on something :)

  • Sorry, ignore my previous comment.

    I was running the OpenGL Example (ActiveQt).

    The project OpenGL Window Example Works.

    I can use it to compare with my project to see what is different.

    I will keep you posted.


  • Hi everybody,

    I found what the problem was. My application needs OpenGL 4. The problem is that I was running and testing my app on a VirtualBox machine that cannot use my computer graphic card. Unfortunately, I will need to install Qt and app on a proper CentOS 7 machine. MRJJ, thank you for your help. Dino

  • Lifetime Qt Champion

    The OpenGL drivers in the VirtualBox Guest Additions are limited to OpenGL 2.1. as far as i know.

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