loffy told you to use CLIP texture, not NODROP… i dunno where you got that from, but nodrop is that no weapons are dropped when you die on it (i think)
but i dont know if that what loffy said is what you are looking for… im also looking for a similar effect… i want a brush to be solid on only one side.
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|__| only solid when you hit the brush from the red side, so you can go ALL THE WAY thru the brush if you come from up, down or left, but if you come from the right you are blocked…
i dunno how to do it… texturing only 1 face with clip didnt work, made the whole brush solid