ice-boy...if you had been paying attention to the entire thread, that was already stated. The sim treats quads like triangles. Just how it splits them though is up for debate ;o). I'm still not sure if it makes X tris (which I think it does treat it like X tris just by the looks of it) or diagonal tris (which I doubt).

BB also stated that it treats each quad like a membrane, splitting it up into tiny pieces, but I think he meant in the rendering and not necessarily the sim ;o).

Laurie