Hello, I’m a beginner with modeling, UVs and all. I’ve created a simple wall mesh to use in UE4, however, the seam is visible between these 2 walls placed next to each other. How can I make it seamless? Thank you.
If the texture itself is tiling, your mesh needs to cover up the whole UV Space if you want to place it multiple times next to each other.
But then I wouldn’t have space for the remaining UV islands. As far as I know I shouldn’t have UVs overlapping, right?
UVs can and should overlap when you are working with tiling textures.
Okay, so it shouldn’t cause any issues. Thanks a lot for the help guys!
One last stupid question, how would I make it so that the stone bricks “continue” on the wall’s corner, so it tiles on every side? Would I have to place the UV islands in a particular order?
It’s impossible to have a box with different length sides title perfectly, but you can get rid of seams on some of the corners by lining up the front and the the matching side and have it go past the 1,1 square, or have it start tiling on the opposite side.
Alright, thank you!
Actually, even without using full uv space you can get tiling and no seams given that the uv island is rectangular. The only limitation is that it works with specific tiling numbers depending on the uv island itself. For example, lets say you used exactly 1/4 of the uv space for your particular face. If you tile with 4 (and 16, 64 etc) and also pan you can “fit” your tiling texture inside the island.
But better way is like others said using the whole space (if your aspect is not 1:1 than stretch along but correct it with giving different x and y tiling coefficients in the engine). The problem is, it overlaps and you can not get unique look for other sides also you may need a second non overlapping uv for static lighting if you use any.
Thanks for the help. I’ve also come across a second issue: I need this texture to tile across this entire mesh, but it seems impossible to do so, at least seamlessly. Is there any way around it?
This shape requires at least one seam but as I wrote before, if you make the final uv island rectangular, it’s not an issue. What you can do is, either place a seam to one of the edges and use angle based or conformal mapping and then straighten up the final uv island. Or as another method, you can use appropriate projections on corresponding faces and then stitch the islands together. What you need is at the end, a single rectangular uv island for entire mesh. I think there will be stretches at some places but they won’t be problem. By the way, in the photo sides look very stretched. You should first get proper uv’s and then work on them to get final proper island if you want to do the stitching method.
I tried to follow the stitching method, so first I did a “flatten by polygon angle” which gave me some good separate UV shells that I then tried to stitch together, however I seem unable to achieve a good result. I’m sure I misunderstood you or did something incorrectly:
If I try instead to place a single seam and then do a “quick peel” (the only way I know of unwrapping from a seam), I get this:
What am I doing wrong?
I think, you understood me correctly. Stitching is sometimes hard to achieve good results even with simpler topology. There is always stretching. That’s seems the case for you. Actually, I don’t use that workflow mostly. You may want to start with least amount of islands maybe? I mean you have around 7 islands but maybe aim to generate less number of islands by doing less projections on more faces(this increases stretches a bit more in islands). This may ease your work. Second image seems very wrong but I am not a max user I don’t know its unwrapping algorithm etc. so I don’t know what is going on there. UV island should have been “almost” rectangular. I’m saying this by looking your mesh. There may be other ways in your software to do better unwrapping. I can recommend another solution but it’s hacky. You can skip stitching, you can make mask for every island and in Unreal Engine you can define variables for UV scaling + translation + rotation for every island with their masks. And by doing manual time consuming fine tuning, you can have seamless material but I think it is not a decent solution and very useful generally.
Basically you want to unwrap that arch like it is a cylinder or pipe. One seam along the “tube” and two seams at either end where the cap would be. You might want to add a slit in the middle of the top if there is any directional detail to the textures, but that depends on the texture and isn’t necessary.
I could not see caps at the ends, I may have missed them. If so, surely there needs to be seems for them also.