I am building a physics simulation engine and editor in Windows. I want to build the editor part using Qt and I want to run the engine using SDL with OpenGL.
My firs
Rendering onto opengl from QT is trivial (and works very well) No direct experience of SDL but there is an example app here about mixing them. http://www.devolution.com/pipermail/sdl/2003-January/051805.html
There is a good article about mixing QT widgewts directly with the opengl here http://doc.trolltech.com/qq/qq26-openglcanvas.html a bit beyond what you strictly need but rather clever!