Querying OpenGL version / getting OpenGL > 2.x in Qt3D, OS X 10.11

Marburg

All,

I'm working on my first Qt3D app --- and first significant OpenGL project -- under Qt 5.7, OS X 10.11, XCode 7.3.1. By starting with some code from Qt3DExtras (and lots of mistakes) I've been able to construct a working scenegraph. My code (based margely on the QPhongMaterial class) uses the APIFilter to select between GL2 and GL3 vertex and fragment shader snippets.

I want to go strictly OpenGL >3, but it sure seems like I'm consistently loading the OpenGL2 shaders (e.g., if I introduce a bug to the GL2 code, I get an error message, if I put a bug in the GL3 code, no error message). This seems strange to me as OS X should have GL 4.x.

I don't even know where to start debugging. With Qt3D as an abstraction layer on top of OpenGL, I don't know how to get to the OpenGL context to read strings, etc.

Neosw

Hi,

When you create the view have you selected a version of OpenGl > 3 ?
In Qt3DWindow constructor, qt team defined the surface with the following code:

...
    setSurfaceType(QSurface::OpenGLSurface);

    resize(1024, 768);

    QSurfaceFormat format;
#ifdef QT_OPENGL_ES_2
    format.setRenderableType(QSurfaceFormat::OpenGLES);
#else
    if (QOpenGLContext::openGLModuleType() == QOpenGLContext::LibGL) {
        format.setVersion(4, 3);
        format.setProfile(QSurfaceFormat::CoreProfile);
    }
#endif
    format.setDepthBufferSize(24);
    format.setSamples(4);
    format.setStencilBufferSize(8);
    setFormat(format);
    create();
...

If you want check if you can load a OpenGL 3 shader, comment the line where you add the shader in the QEffect:

   // _phongEffect->addTechnique(_phongAlphaGL2Technique);

You can also check if you have add the good number of version on the top of you shader file.

Marburg

I was able to get this working by explicitly setting the default QSurfaceFormat at the top of main():

    // Set default OpenGL version
    QSurfaceFormat format;
    format.setMajorVersion(3);
    format.setMinorVersion(3);
    format.setProfile( QSurfaceFormat::CoreProfile );
    QSurfaceFormat::setDefaultFormat( format );

It's interesting the code from the Qt3DWindow constructor doesn't seem to be effective (?).