Use Floor Segments, not boxes.
Although this brings up something else, if the engine does ANYTHING right, simply covering the ceiling will do nothing... you, my freind, have a poly leak.
What Happened:
Polyleaks are hard to explain, basically, you are loading more map then you should be, and you can't tell why. I have found several times that polyleaks can occur from single mesh objects [the types used to place doors or windows].
I have also found that single sided floor segments are more likely to produce a poly leak then a double sided segment, however, double sided segments do seem to load both sides.
There is even the strange occurance when a part of the map is impropperly added in, and it zeroes FPS.
What has happened.
It would appear to me that your 'box' has separated that area of the map with the bad area...
Poly Leaks is not the correct term, I admit that, but I commonly use it to describe what I consiter one of the biggest problems in FPSC.
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