100% of game engines require to have any and all geometry triangulated prior to it it being inserted as a game asset. This goes from simple objects like a box to the 80,000 poly cars we see in games on the Next Gen Consoles.
As far as I have read the reason for triangulation is to do with the speed of the processors math calculations. CPU and GPUs can calculate tris faster than quads.
I dont think there is any other reason behind it to be honest, its all to do with realtime calculations of the geometry by the GPU and/or CPU.
Chris (formerly R@nSiD)
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