Displacement Trouble

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Balloonsfor600

L1: Registered
Sep 7, 2009
45
18
OK. So I have the basic jist of how displacements work and what they are used for. I am working on my first map in Hammer and the first map that I plan on carrying through to actually releasing. If you care, it's a ctf map in a snow setting.

Now, last night I was doing some work with displacements. I did some cliffs around two edges of the maps and a nice sort of rock formation in the middle the other night. Whether they stay or not is debatable, but it was more for practice and I really liked how they came out and I had no issue with any leaks out into the void.

However, last night I decided to try and form the ground between the red and blue base. It's quite an expansive area, so I broke it into several smaller displacements before starting work. In some spots this was a necessity so that the terrain shaped around the buildings, not through them. I ended up with a lot of leaks into the void that were pretty noticeable and spent a couple of hours bumping the displacements into each other in order to hide these seams because for some reason the sew function would not work.

I really want to get my map into a playable alpha to test the layout. Technically, the displacements are fine now, but I am worried about making changes to these displacements later because I know that I am not to the point where I am satisfied and as I get into detailing the map, they will change in several spots.

This brings me to the question that has been bothering me all day. Should I keep the displacements as they are for now and possibly just delete them and start them over on my second pass of geometry? Should I try to reduce the amount of space that I use displacements by using some more intermittent buildings (planning on doing this to a degree anyhow)? Should I just leave it flat and do extensive architecture between the bases (another consideration I have)? Or should I keep with my present idea and just redo the displacements on the first pass of geometry by making some of the smaller ones into a single large displacement (what I am mainly considering)?

Are there any tips someone can give me that may just help me resolve this conundrum more easily?

I apologize for no screenies, but I am not at home where I can reach my map right now. I will post some later if you guys ask for them.

Thanks for the suggestions!
 

Bslashingu

L2: Junior Member
Jan 29, 2009
53
11
You don't need to bump the displacements together in order to seal the cracks in the displacements. If two brush's corners line up, you can use the sew button to seal the cracks automatically, it works for any number of displacements, just line everything up (use the vertex tool or clip tool if you have to), select the faces in the texture browser and click the sew button, then everything should align together.
 

Terr

Cranky Coder
aa
Jul 31, 2009
1,590
410
The key rule for displacements is that they have to be four-sided. And from that, if you want to use the "sew" feature with two of them they need to share an edge. (Or the smaller one shares an edge for exactly half the length of the larger one.) This is why you can make a rectangular solid and displace every single side--they always match up with each other.

You can also sew displacements to normal brushes, if the same edge-sharing rules are kept.

Displacements are also relatively cheap: Using them for rough ground isn't that much worse than having flat ground.

__________


For your ground issue, I'd step back and look at how you want to arrange your buildings, and try to figure out what patchwork of squares or deformed rectangles you can use to cover the ground outside the buildings. Then use the vertex tool to make sure all your displacements smoothly meet each other, which is easiest to do with :disp3d: turned off. You can also use :dispmask: to show the non-displacement sides (which are normally totally discarded during compiling.)
 

Terr

Cranky Coder
aa
Jul 31, 2009
1,590
410
BTW, here's a slapped-together example. The blue areas are buildings, the red lines separate displacements (which otherwise hug the walls). Each displacement is named with a letter.

dispexample.png


This may not be the best way to do it, but unless I made a mistake somewhere it should all sew together.

In C you can see we used the "T-junction" half-way point to sew. C and E won't find each other via "Select Adjacent", but they will sew if you have them both selected.

With K you can see one way of recovering from a sharp corner without making a triangle.
 

Balloonsfor600

L1: Registered
Sep 7, 2009
45
18
Thanks a lot for the quick responses. I think that I will leave it until I finish the rest of the geometry and run my alpha with some friends (and any volunteers from here) and then I will fix it up after I have tweaked the rest of the geometry. Thanks again for the suggestions. If anyone else has any displacement tips, I'd love to read them.
 

Balloonsfor600

L1: Registered
Sep 7, 2009
45
18
Sorry to rebump my thread, but I thought of another question. Should I sew the displacements together before or after I do the actual displacement?
 

Terr

Cranky Coder
aa
Jul 31, 2009
1,590
410
Sew whenever you want.

It doesn't "sew" things together in any permanent way. They aren't linked or joined or grouped. If it helps, pretend they named it "Smooth Adjacent Edges Of Selected Displacements". :)
 
Last edited:

Freyja

aa
Jul 31, 2009
2,994
5,813
It just connects them so they're seemless.

It also helps if you select all the displacements at once so when you're editing them you don't open up any holes.
 

Balloonsfor600

L1: Registered
Sep 7, 2009
45
18
Gotcha! Thanks again for the help. I wasn't 100% clear on how they worked despite several tutorials - thanks for the tips! All cleared up now... hopefully.