first i set the environment to QSG_INFO=1 to enable opengl debugging. QLC+ shows me he is using version 2.1
next (and after googling) i added to qmlui/main.cpp before QApplication app(argc, argv); the lines:
--SNIP--
QApplication::setAttribute(Qt::AA_UseDesktopOpenGL);
QSurfaceFormat format;
format.setVersion(3, 3); // as requested by QLC+
format.setRenderableType(QSurfaceFormat::OpenGL);
format.setProfile(QSurfaceFormat::CoreProfile);
QSurfaceFormat::setDefaultFormat(format);
--SNIP--
OK, now QLC+ shows me the correct OpenGL version
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But now i get some stange messages by loading the 3D view:
QOpenGLShader::compile(Vertex): ERROR: 0:1: '' : version '110' is not supported
I take a look at the code and found the corresponding code in GeometryPassEffect.qml and now its getting strange....
in GeometryPassEffect.qml are code for OpenGL 2.0 and 3.1 and every time only the code for 2.0 will be used. i wonder how this works. the code looks clear to me.