Bug in qtdatavisual3d Abstract3DRenderer?

[Tom asso]

I'm running Qt 5.13.0 on Ubuntu 16.04.
Many of the data visualization apps from the qtcreator Examples page fail with this message:

OpenGL version is too low, at least 2.1 is required

Yet glxinfo indicates that my Ubuntu machine has OpenGL version 4.5:

glxinfo | grep "OpenGL version"
OpenGL version string: 4.5 Mesa 18.0.5

This message is generated by Abstract3DRenderer::Abstract3DRenderer (), defined in datavisualization/engine/abstract3drenderer.cpp, which includes this:

        m_funcs_2_1 = QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_2_1>();
        if (m_funcs_2_1)
            m_funcs_2_1->initializeOpenGLFunctions();

        // Restore original message handler
        qInstallMessageHandler(handler);

        if (!m_funcs_2_1)
            qFatal("OpenGL version is too low, at least 2.1 is required");

If my system has OpenGL 4.5 installed, why does QOpenGLContext::versionFunctions() fail for version 2.1 functions? Why does Abstract3DRenderer insist on 2.1 functions if version 4.5 functions are available?

Thanks

[Tom asso]

So is qtdatavis3d's Abstract3DRenderer just not compatible with desktop OpenGL versions higher than 2.1? If so that is pretty limiting!

I've written a short test to verify that QOpenGLContext::versionFunctions() returns nullptr for QOpenGLFunctions_2_1, but returns an object for QOpenGLFunctions_4_5_Core on my Ubuntu machine (which has OpenGL 4.5 installed).