what egor says thou I disagree with this bit.
[R-DEV]e-Gor wrote:My personal recommendation would be to put the window frames in the collision mesh and the lod1 (remember the lod1 doesn't want to be too low poly, as this is seen close up when you have your graphics settings on low), and remove them for lod2. At the sorts of distances you're likely to get col2 used, it shouldn't be too much of a problem.
personally I would not do that, what I would do instead is keep lod0 like you have it now more or less, maybe optimize it a bit, then with lod1 I would remove the frame, and would then texture the inside face of the window like it was metal.
then for col0 I would use more or less the same system for as I did with lod1, have no frame and on the inside face of the window, give it a metal material.
This would mean that bullets would go though the very small frame but as its such a small frame, gameplay wise this means nothing, all you really loose is the effects. If you hit the side of the window near the frame you will get a metal effect like it hit the frame, providing you set up your materials etc.
EDIT: in fact I would not complety remove the frame for col0 and lod1, I would leave the middle bar in place and extend it to the edges, with giving it a metal met on the col as this will have a bit of a impact on gameplay thou the rest I would keep the same.
it is important that your cols are as low poly as possible.