If you take a look at a F1 Grand Prix, just before the race start, you see all the cars lined up on the grid. Steam coming out of the engines just deform the aspect of what''s behind it, because the air is veryu hot and turbulent. How can this be done with opengl ? Just because my english probably is too poor to represent what i mean, take a look at this screenshot, and tell me how could they do that ! I''m very curious. http://www.lo-mac.com/screens.php?id=395
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Something about that screenshot is hokey, but you can do the desired effect with refraction mapping, I think.