"Hard Edge" on UV Seam.

FW911TTW

[FONT=&quot]Hi there.

I am having what seems to be a lighting issue with my house model in UE4. At the two corners of my building I have my UVs cut. On these seam lines is where the issue resides. The corners of the house are rounded with 5 subdivisions (I believe that is the correct terminology). The cuts would be on the center division.

Screenshots Out of UE 4:

---

My Normal Map+Normal Map with UVs:

---

Added bonus:

---

ALL the edges on the model are soft. Normals were unlocked. I Have tried putting a "neutral normal map blue" color on the borders of the normal map. No luck. I tried taking it into Substance painter and repainting the corners. It looked good in Substance, but then I brought it back into UE4 and the problem worsened. I had even tried breaking my link to my normal map and the problem is a lot less noticeable, but still there, and I have no normal detail with that "solution". I talked to both of my lab instructors and even the both of them came up empty handed with what we tried.

So far the only solutions I have come up with are Re-UVing the house so the corners are not the ones in the shot which means a lot of Photoshop work (shifting texture, normal, roughness and metal maps (And the problem would still be there, just not seen)), or simply Photoshopping the beauty shots to look right for when I submit this tomorrow. Even if that ends up being the case, I still want to know where this issue is coming from.

-FW911TTW[/FONT]

WarrenM

Try flipping the green channel on your normal map. You can do that in the properties of the normal map in UE4.

FW911TTW

WarrenM,

Nope. That didn't fix it. Even if it did then my roof tile's normals would be wrong.

Vailias

Suggestion: Bake out an object space map rather than tangent space, then convert it to UE3 tangent basis with handplane.
Also, if you're using a cage, try making it align more closely tot he high poly surface at those points in the mesh. Or reducing your ray distance if you're not using a cage.

There's definitely some incorrect vector information in your normal map at the edge. The final picture shows this remarkably well. Light is hitting from the "inside" of the wall based on your light vector, so those normals have to be pointing at least somewhat toward the light, which is definitely not what you want.

FW911TTW

Vaillas,

I tried that, but my house looks like a giant sponge now and the edges issue is still there, but before I brought it into handplane the colors in the object basis had a slight variation at the edges like they rounded, so it must have tried to do something, and then it lost progress when converted to a tangent basis. I also double checked the UVs to make sure they were on the right channel and not the light map and everything checked out.

Farfarer

It looks like you've just uniquely unwrapped the house, thrown a texture on it then run that through CrazyBump or something similar. You're not going to get a clean normal map that way and the seam won't go away unless you tone down the big details in the normal map (and even then, you won't get away with them entirely due to how you're making your normal map).

I'd really recommend looking into using tiling textures for the mesh - that's a really wasteful and inefficient method of doing this sort of stuff. It'll help seams like that too and you'll get a higher overall texel density with the same total texture size.

Ssjtroll

Yeah so I think that is light map bleed actually. Here is a awesome video. If you can follow this and when you snap those edges to the grid in lightmap channel hopefully that will give you more of the result you are looking for. https://www.youtube.com/watch?v=gEKjk049bUU&list=PLA59F1E61EB00AF17&index=22

Dklang

Farfarer wrote: »

I'd really recommend looking into using tiling textures for the mesh - that's a really wasteful and inefficient method of doing this sort of stuff. It'll help seams like that too and you'll get a higher overall texel density with the same total texture size.

are you saying tiling textures is wasteful or better?

passerby

he is saying you can accomplish the same thing with tiling textures, using less texture space but still haveing high res. Just takes some more creative UV mapping and re-use of existing texture space.

Farfarer

Dklang wrote: »

are you saying tiling textures is wasteful or better?

Yeah, that was poorly worded, sorry. I meant that doing one massive texture for the house is very inefficient.

A few well made tiling textures will not only be more efficient, but allow a higher (perceived) level of detail.

Dklang

so you guys are saying that each part of the house has its own texture file rather than squeezing all UVs for one texture file? I usually just use tilable textures but I cant add dirt or decals when doing that and the alternative gives me blurry texture. Also there is the question of lightmaps, shouldnt the whole house have 2 UVs and not each part of the house?

Farfarer

The lightmap IVs should be unique, yes.

But yeah, for everything else I'd use tiling textures and maybe a shader that blends between a couple of variants so you can add a bit more interest. Decals help, too, to break up the tiling.