At E3 this weekend I saw a very cool effect in (grumble) Microsoft’s Mechwarrior. The effect was a zoomed in window in the center of the screen. This can be accomplished (I think) in OpenGL by using two calls to glViewport like such
glViewport(0,0,width,height); // Main Window
glViewport(350,250,450,350); // inner zoom window
However when I attempt to do something like this, fragments from the main window randomly overwrites the inner window… any ideas on what I can do to fix this? perhaps strategically placed glFlush calls? or PostRedisplay calls? Any help?