Oh yeah, each seperate brush is a surface, and each seperate mesh even if it shares the same brush with others is a unique surface.
so if you have a lanpost copied about your level with a single brush applied, each lampost becomes a surface.
if the lamp post has 2 brushes, metal for the post and a lamp texture that becomes 2 surfaces and doubles your surface count.
However if you combine all your lamposts into a single mesh with the one texture your back to 1 surface again.
Of course your lammposts are strewn about your level, and if one lanpost is visible all lanposts in that mesh will be drawn. So you have to judge for yourself how to split this up for maximum efficiency. If you keep the surface count fairly low you may get away with 80'000 polys drawn per frame and not have to worry about occluding polys so much.
you still have to juggle your collisions and linepicks though, as these are other CPU hogs that will reduce how many polys can be drawn if you don't design your engine intelligently. Usually low poly hidden collision is the best way to go and will give you a surprising ammount of flexibility if used right.
so if you have a lanpost copied about your level with a single brush applied, each lampost becomes a surface.
if the lamp post has 2 brushes, metal for the post and a lamp texture that becomes 2 surfaces and doubles your surface count.
However if you combine all your lamposts into a single mesh with the one texture your back to 1 surface again.
Of course your lammposts are strewn about your level, and if one lanpost is visible all lanposts in that mesh will be drawn. So you have to judge for yourself how to split this up for maximum efficiency. If you keep the surface count fairly low you may get away with 80'000 polys drawn per frame and not have to worry about occluding polys so much.
you still have to juggle your collisions and linepicks though, as these are other CPU hogs that will reduce how many polys can be drawn if you don't design your engine intelligently. Usually low poly hidden collision is the best way to go and will give you a surprising ammount of flexibility if used right.