[Qt-interest] where do you initialize Opengl?

[Shi Yan]

hello guys,

i'm writing a simple 3D CAD tool. i'm using the Model-view pattern. i
have several qglwidgets representing different cameras viewing the
same scene and a singleton class, which i call a "Scene".

inside this "Scene" class, i define the geometry that needs to be
rendered and initialize GLSL shader language, etc.

the problem where should i call Scene.init() ?

one option is calling it within the initializeGL() function of a
qglwidgets. but there are many qglwidgets in my program. if i call
scene.init() inside initializeGL(), then the initialization will
execute several times.

however, if i call scene initialization somewhere else (for example in
the main function), it will fail, because the opengl context hasn't
been set up yet:

main()
{
    QApplication app(argc, argv);
    MainWindow mainWindow;
scene.init();
    mainWindow.showMaximized();
    return app.exec();
}


is there anyway to initialize opengl related settings right after QT
sets up the opengl?

i think QT should pop up a signal after setting up Opengl. this signal
should be emitted by a global object, say QGLContext.

and then, i can write a slot, once the opengl is ready, i call my
initialization function.

hope you can give me some advice.

is the Qt team reading this ?  what do you think about the
"Opengl-ready signal"?


thanks.