Hi everyone,
This thread is probably in the wrong place, and I failed to find one that deals with this exact problem that I’m having but gotta start somewhere :).
This is actually a recurring issue, so I’ll try to describe it as simply as I can.
I made a pillar out of one brush object (box), lets say it has about 6 different splits that were then shaped using the pen tool.
When this pillar is placed against another brush object (box), unmodified, a portion of this object (where the pillar is covering it) becomes invisible; as if that one portion of it had a “deductive” visibility option (or whatever is opposite of additive).
I can’t imagine this issue not been mentioned before, so if anyone can point me in any direction - thank you in advance.
-Tom
I moved your thread to content creation.
Could you probably post a picture of your problem? 
That’s how BSP works, when you put brushes together it creates new geometry without the part that intersects.
fighter5347,
Aye, here is a butchered brush next to a generic box, you can see the gap where the background is showing through.
darthviper107, I sure hope this is not how geometry objects are supposed to work in UE, cause that’s just someone bad idea of a joke.
Hi tbob418,
Can you post this to **AnswerHub **in the Bug Reports section? This way we can assign this to one of the support staff to look into. I’m fairly certain this is a known issue though which has been reported.
If you convert the BSP to static mesh I believe it will resolve the issue, but it won’t be editable any longer like BSP though.
Hi Tim,
I posted about it in the Bug Report, we’ll see what happens.
Converting to a static mesh does work, but also, as you said, it’s obviously no longer editable; which is not necessarily an issue when/if you know you are done with editing…
Thanks
It shouldn’t be missing polygons like that, it should just get rid of the part that’s not visible, so that’s probably a bug.
This was already reported with UE-12157.
Thanks.