Now, I know the main option would be roombounds, however they can be very tricky and time consuming to set up, so I'd love it if I can avoid that.
So my question is, is there a downside to using occlusion planes to cut up a level instead? I can place them between large rooms (outside of the rooms in the deadspace, obviously) so that the other areas aren't rendered. However, this almost seems to me like it would be very processor heavy, if with every step it's recalculating what the engine should and shouldn't cull. Is this assumption correct? Or am I assuming incorrectly? Will placing, like, 3-10 occlusion planes around a level between large areas actually reduce performance, or is that calculation very minor, and will the saved rendering more than make up for it?