Brushes not staying lined up after compile

Pocket

Half a Lambert is better than one.
aa
Nov 14, 2009
4,694
2,579
So I've got a really weird problem. I had just discovered that arches and cylinders always snap to the grid, which of course makes manipulating them a lot easier than I had thought, so I thought I'd try making a simple spiral staircase with a smooth underside. After a lot of messing around with vertex editing, I had something that looked perfectly fine in Hammer but, when I compiled, suddenly broke up into a jaggedy surface, thusly:

brokenstairs.jpg


And I'm like, WTF mate? All four corners of each step line up with the grid just fine, so it can't be that. (And yes, I did turn the steps into func_details, not that it's relevant.) And there's no unusual slowness to the compiling process or errors. So what is causing the compiler to choke on the coordinates of the steps so badly?
 

pitto

L3: Member
Feb 17, 2009
109
73
I think the problem is because each underside face of the step has four points, and these points are not co-planar (cannot make a flat plane through all four)

Really a spiral stair case would be best done using a model, however if you really want to use brushes you could try cutting each step along the diagonal so the underside faces are all triangles. Since there is always a flat plane through 3 points it should work, however I would expect that you could end up with odd lighting.
 

J4CK8

L11: Posh Member
Mar 4, 2009
820
243
Try alt+p. By the looks of it hammer will probably say that those solids are invalid, and if you click fix they will end up like they do ingame. I would suggest trying what Pitto said, but if it still fails, you may need to use a model, scrap the idea or just make do with what you get.
 

Pocket

Half a Lambert is better than one.
aa
Nov 14, 2009
4,694
2,579
I think the problem is because each underside face of the step has four points, and these points are not co-planar (cannot make a flat plane through all four)

Really a spiral stair case would be best done using a model, however if you really want to use brushes you could try cutting each step along the diagonal so the underside faces are all triangles. Since there is always a flat plane through 3 points it should work, however I would expect that you could end up with odd lighting.

I noticed that they say to do that, for like ramps and stuff, and couldn't figure out why; in Hammer the shading is vague enough that they looked perfectly solid so I didn't bother. I'll be trying that and it will probably work. Thanks!
 
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