BSP and max draw distance

haarp

Is it possible to get BSP to hide in the distance? You can select the BSP brush and give it a max distance but it doesn't work. Is my only option to turn it into a static mesh? If so, I'm having trouble with that, I'm creating a ruined building and even when selecting all of the brushes (the brushes that remove geometry) it only saves it as one big brush and takes no notice of the edited geometry.

alecchalmers

I've had a closer look at cull distance volumes and I can't work out why, but BSPs don't seem to be affected by draw distance, even when you set their individual draw distance and set it to override the cull distance volume. I can't get them to be affected at all. I'd be interested to see if you can solve this problem, as this must have been an option at some point, otherwise it wouldn't be in the properties.

alecchalmers

If you can't change the draw distance, it's possible you could control the visibility of the BSP's material in relation to the player/camera. If it turned invisible at a certain distance, this would have the same effect pretty much. You could also allow for softer transitions this way, instead of it popping in and out of view.

alfalfasprossen

dudes BSP aren't single meshes it is a form of how to partitionate a single mesh into small chunks that are displayed according to how a BSP-Tree works. All the BSP brushes form a single mesh. It is mainly a legacy from the old days, when BSP was used to build whole levels. Nowdays it is only used for blocking out and playtesting your initial concepts. Although of course nothing prevents you from building your whole level out of BSP, but it will perform very bad and will lead to geometry problems.
Actually the correct term for BSP-Brush would be CSG-Brush, as the operation to form one mesh out of those brushes is called Constructive Solid Geometry, but the Term BSP settled with the people instead.

If you need more info, google or ask wikipedia for the terms BSP (Binary Space Partitioning) and CSG (Constructive Solid Geometry), you should then understand why BSP is a bad decision for vast environments performance wise and if you want to dive into other problems, google BSP-hole just for fun


To conclude: you are supposed to use Static Meshes to build your levels. Max Draw Distance and stuff like that will not have an influence on BSP because it will be one single mesh in the end and the culling of parts of that mesh will be decided by another process than those that cull Static Meshes and alike.

alecchalmers

Thanks for clearing that up. I never use BSPs for anything other than blocking out because I was told to, but never told why, so I assumed that maybe it wasn't all that bad. Now I know, thanks alfalfasprossen