Tip for unwrapping large surfaces like walls, floors, and ceiling of room?

local306

Anyone here have recommendations for guides, tips, techniques, etc, for UVing a room? i.e.) floor, walls, and ceiling of a bedroom as an example.

I mostly work with props and characters, so going up to this size is kind of new to me. Obviously I know how to unwrap, but I'm looking for suggestions on how to be more intelligent with unwrapping to keep material count low as the end product is going to be deployed on mobile VR and reducing materials / draw calls is pretty key for optimization.

Most of the props designed for the room are around 2048 px / m texel density. Curious as to what's a good way (if possible) to maintain this standard for much larger geometry like the walls, floor, and ceiling of an average sized room. Like would you apply something similar to a trim sheet to your large surfaces, and then divide the mesh into respective units to fit onto a single UV tile?

Sage

You need to determine the texel density you want to use. Once you do that every meter should have a loop. This depends on your needs of course. The reason you put a cut in the wall is that there is where the texture will repeat. One thing I like to do is turn on the preserve UVs option and that makes making corners really easy and allows you to extend your meshes.

The reason I am showing you trim sheets is that you need to use seamless textures to texture your models to get decent resolution. The trim sheet is just a texture atlas that tiles usually in one direction.

https://www.youtube.com/watch?v=DipfrjCgYW8
https://www.youtube.com/watch?v=IziIY674NAw&t=935s
https://www.youtube.com/watch?v=ozi57FHucNI
https://www.youtube.com/watch?v=ozi57FHucNI

local306

Thanks @Sage.

Would you be able to explain what you meant with the Preserve UVs option you mentioned? Curious to learn what this is for whatever tool you might be using.

Sage

Here is a video I made. Hopefully, it helps clear things up.
https://www.youtube.com/watch?v=Jp_I608DIss

toxicsludge77

@Sage I'm curious as to why you would need loops every [x] meter. If your floor was 6 meters across and you use a (eg) 2k tiling texture that covers a 1 meter area, wouldn't you just unwrap the floor with the correct TD (in this case 2048 px / m) and the texture would tile 6 times?

Kanni3d

toxicsludge77 said:

@Sage I'm curious as to why you would need loops every [x] meter. If your floor was 6 meters across and you use a (eg) 2k tiling texture that covers a 1 meter area, wouldn't you just unwrap the floor with the correct TD (in this case 2048 px / m) and the texture would tile 6 times?

You could do it like that, but sometimes, especially in mobile, there are atlases of tileable textures, which sounds like an oxymoron, but is utilized to cut down 4 drawcalls/materials into one. Since you cannot tile, you'd have to cut your geometry to fit it into the quadrant with the desired tileable texture. That's my assumption as to why he'd place extra loops every metric.

toxicsludge77

@Kanni3d Ah yes, that makes sense. Thought I was missing something. 2048 px/m sounds like a crazy high TD for mobile though? VR I guess needs this kind of TD?

Sage

Here is a follow-up video to explain the cuts better. Kanni3d kind of explains part of the reason I  said you need to add cuts to the modules. Lightmap resolution, keeping consistent texel density among all the assets is part of the reason to have to make cuts in the model. It really depends on the pipeline the project has.

It's a little hard for me to explain this while I'm doing it, so I hope the video wasn't too confusing. In this video, I try to demonstrate the texel density problems you might run into when texturing large assets.

https://youtu.be/QllSrvOwsXQ

local306

Sage said:

Here is a video I made. Hopefully, it helps clear things up.
https://www.youtube.com/watch?v=Jp_I608DIss

Thanks @Sage for taking the time to put together that video.