View Full Version : How do YOU fix BSP holes?

14th Apr 2000, 01:14 PM
Might be kind of nice for the novice mappers here to hear how other in the community deal with (or avoid!) the bane of a mappers existence- BSP holes. I know how frustrating they can be and Im sure Im not alone in wanting to know the various techniquess for fixing them.

One technique that worked for me, is that the lighter your background or skybox, will show brightness through the holes. By making sure that terrain/buildings are totally touching the background, or inserting a darker brush barrier between the skybox and the brush with holes, if possible has seemed to help.

Another suggestion that I recieved, but that is to move the entire map to an unused area of the grid. Im unsure of the logic for this, and it only seems to work marginally well for me.

OK, what does everyone else do? If the topic does well, might be nice to turn it into a small tut to post on the site as well, so lets hear it.

RealMaps Site Coordinator
Want to be an Infiltrator? Get the goods at:

14th Apr 2000, 02:33 PM
i actually had to move my map on the grid--i had this weird dark spot that when you stepped into it you cratered. to get rid of bsp holes though, i just find a hole, play with the slider bar until it goes away and then look for another hole. works good so far...


14th Apr 2000, 03:27 PM
IMHO, when you have a real bsphole (not some glitters like CC described) you did something wrong. I agree that sometimes it goes away when using the slider, but I don't think that's the solution. And lost, what were you doing outside the grid ?

You can't do much about the glitters that seem to appear with complex brushes, maybe that's the reason why there are so many UT levels with a night setting.

14th Apr 2000, 03:52 PM
I've been able to get rid of the majority of BSP holes in my levels by reordering the offending brushes (right-clicking them and choosing "move to first" or "move to last"). Play with it a bit; it's not too hard to figure out.

The BSP optimization slider will fix the problem sometimes, but it usually screws up other things, so I have to strongly recommend against using it.

I've seen a lot of talk about how using a small grid size will create BSP holes or screw up other things, but it's never happened to me (and anyway, it's the only way you're going to be able to create a detailed level with a realistic scale). The only annoyance is that there's a bug in the vertex manipulation code when you're moving a vertex that has another vertex less than eight units or so from it.

14th Apr 2000, 06:31 PM
i never left the grid or turned it off, i had to select all actors and move it over a little bit. there was this weird black hole kind of thing...


14th Apr 2000, 07:07 PM
BSP holes, glitters & xmas tree effects...

The bain of my life... I think I spend 10% of my building time checking for these and fixing them.

Anyway we have to live with them, because it seems that no matter how accurately you build...

All the above stuff is useful... humm slider this can cripple your level, A pro once told me "Leave all the defaults alone"...

So defaults are left alone, I did try this one but found the hole just moved around or even made more.

Changing the brush order, indeed I have seen this work, but be careful with subtracts..

Many people will have different views on this topic but I can only say what I do...

I always turn vertex snapping off.
I always align my SOLIDS (blue) to the grid ie the brushes are always scale (1,1,1) and size in povers of 2,4,8,12,16,32,48,64,128 etc etc.

Semi-solids say pillars and roof eye-candy I tend to leave as is, ie no de-insecting necessary, overlap, etc.

Sometimes making a solid semi can help as long as you are careful, tricky this topic, works sometimes not others... I have had stairs as semi's before and they are fine, but again a different level and this doesn't work... So if you can avoid it leave all brushes you intend to walk on leave them as solid.

Oh yes... Semi's do not make bsp cuts...

For BSP holes go to the 3D zone view, this shows not only the zones but the bsp cuts.

Look for the hole and see which cuts are near the bsp hole, look at which brushes force the bsp engine to cut your level like it has, try moving the brush that you think causes it, reshape it even... Even add another brush in that area, that works also...

Sadly BSP holes tend to be trial and error to fix, but if you build well this lessens the problems you will get.

Hope some of that rambling helps..


15th Apr 2000, 08:20 AM
Ah, I dont get it, for DM-BootCamp I have a HUGE hole to fix, and I cant do IT! I sticked with da scale, but I NEED A SOLUTION!!! Bad!

SFA Clan Sniper

As long as I live!

Loyal to SFA!
As long as I live!

15th Apr 2000, 06:10 PM
Could you make small jpg images from the 3D view, so I could see your Zone view of the hole, plus the exact same view but in texture and pers views.

This can be done btw by giving the 3d view focus by clicking on it, then hit the <alt> PrintScreen keys, then load up your jpeg saving program and paste and save...

Sorry if you knew that already dude. If you don't have a good jpeg saving program use my FREE one... pimp pimp. /infopop/emoticons/icon_smile.gif

(Wrote it a few years ago, still good for viewing and saving images).


15th Apr 2000, 10:22 PM
Actually lost you've got a good point there. It you get holes, moving the ofending brush (or the entire map), even just a sqaure in another direction usually fixes it. I don't think it helps with the XMAS tree stuff, but for gaping holes it does help.

Evil Joe
16th Apr 2000, 05:11 PM
x-mas lights or rips are different then bsp holes. First thing to do when you encouter bsp cuts. (Don't ever use the slider what are you insane!) Click on optimal, 9 out of 10 that gets rid of them for me, if you get a lot of bsp cuts and this doesn't fix them, I strongly encourage you to reconsider the way you are mapping. Reordering is fine but should be close to a last ditch effort cause it screws with stuff sometimes; screws with stuff bad.

Instead of reordering (this is a method to use in place of reordering) right click on the poly and copy it to brush delete it and then add the brush that will order it to last for ya.

Here is an obvious one, remove the offending brush. And then reconstruct that brush but this time DO IT RIGHT. Editor didn't like the way it was built (or placed, in which case it should be moved like on the grid), if you have used some 2d editing, imports, or vertex editing (which I as a practice do not use cause in editor it isn't that great, its not true vertex editing and it usually causes more problems then it solves) chances are you messed something up in its construction.

If you've tried all of these and it hasn't worked for you... ouch is all I can say. Rethink your mapping. Remeber kids editor loves subtracts but hates adds. Make brushes by carving NOT stacking whenever possible. Oh and coffecan, it is generally never a good idea to have stuff touching the walls of your "level".