[vtkusers] Mixing OpenGL code with VTK

[Sebastien Auclair]

Hi folks !

THE QUESTION :  Is is possible to use a VTK render window to display OpenGL
command ? (Mixing both approachs  ?)

CONTEXT :
    We have this soltware that was using OpenGL to draw shapes. (In a
QGLWidget QT rendering windows)

    We would like to use VTK for some special drawing features but we don't
want to loose the previous OpenGL code. We've replaced QGLWidget with
vtkQGLRenderWindow but we can't make the two work together.

If it is possible, what would the correct calling order be for stuff like
vtkRender::Render() VS glFlush() etc...

Thanks in advance !