[Solved] What function brushes do NOT generate visleafs? ^Title I'm making a map wherein there's a massive glass wall that separates one section of the map from the other (not practical for a normal map, but I'm just testing some ideas). When you hit a button, the glass wall turns opaque (or, rather, gets switched with a different wall with a different texture). I've managed to get this part to work, but I was hoping to cut a lot of holes in it (10+ holes for sniping spots, etc). From what I understand, portals generate at every edge of a brush, and I was hoping to avoid this as the compile time is already quite long (for all I know, all of those holes could make it take hours to compile). Also, I can't set it to a func_detail as I see no way to enable and disable it (or name it to begin with). So, what brushes can I use to make this work, and generate no visleafs?