(1) Do areaportal brushes also double as visleaf hints? Seems like they ought to, since pretty much every areaportal represents a doorway or window of some kind, but I'm getting some places where it's dividing up the visleaf on one side based on the hole's vectors. (2) I was planning to add draw distance to all my props that's high enough that it only fades when it's around some sort of corner anyway. But since being around the corner almost always puts the props into a different visleaf anyway, is this actually going to help anything? Is draw distance only for making props fade out while they're still technically in your field of vision? (3) I have a set of silos in two rows, touching. There is also a building touching the set on one side. Between them, you can't see around them, but the silos have to be a func_detail. How do I go about blocking visibility? Allow me to demonstrate with a visual aid. The people in the red area can't see into the green area, and vice versa, but they need to be able to see everything in their own color area.