UV shell grouping

[trevor.adams]

(Copied from original User Voice forum)

"Group stacked UV shells so that they can be packed using 'layout' as one stack. This would be excellent of real time/game UV's. A further extension to this would be to offset the stacked shells to a separate UV tile ( -1, +1 etc) for baking purposes. An even bigger extension to this could be that the stacked UV shells  (as long as they are exactly the same as the initial UV count) can be manipulated like an instance of the initial UV shell in the group."

[sublist]

This is so important for Game UV Layouts!

A better packing algorythm would be much appreciated as well!

[trevor.adams]

@sublist, can you post a separate idea for the ways in which you'd like to see UV Layout's algorithm improved upon?  Or do these ideas listed here already cover what you're asking for?

[sublist]

Hello.

No that is not covered by the other topics.

I'm talking about the packing algorithm. So just the math behind this feature. 😉

[mickeal_alex]

Keep overlapping uvs is very important for games, when doing a Layout command it doesn't keep the overlapped uv's on top of each other and doesn't treat them like one uv object. The option to stack similar uv's doesn't give you enough control, some uv's that are similar you may not want to keep overlapped for example for AO where one uv has a shadow and the other doesn't.

[ValentinN84]

The group stacked UVs part looks to me like it's the same request as this:

https://forums.autodesk.com/t5/maya-ideas/option-to-preserve-overlapping-uv-shells-during-uv-layout/...

I subscribe to the idea that this should be implemented. Rizom Labs' Unfold 3d (which I guess Autodesk licenses for Maya) did implement this feature in their 2018 version.

Also great in that version is the ability to group UV shells into smaller smaller layouts. For example this allows for more logical UV layouts where each object's UV shells are kept together in the final layout.

As for the offsetting flipped UVs, Maya 2018's UV Editor has the option of selecting flipped UVs. It's in the UV Editor menu: Select -> Back-Facing. These can be manually offset.

There's also the case where the overlapped UV shells are not necessarily mirrored so then the problem then becomes "which shell should be used for baking". I don't think this can have a simple automatic answer and that for this case the user should select the desired UV shell and then Shift+Drag Select over it to select every other overlapped shell bu the desired one and offset these manually.

[mickeal_alex]

I don't recall having the ability to stack overlapping uv's when doing a layout operation and by overlapping i don't mean every uv but the ones i already prepared. The way i uv's map object for videogames is i basically do a automatic map, cut along hard edges for normal map and then try and overlap similar faces than have the same shape and that has the same ao when it will be baked. When i have set up the object and i have already overlapped uv's when i do a Layout whatever settings i use the uvs that are overlapped aren't treated as one uv and as far as i know the latest version of Maya doesn't have this ability.

[reva2101]

I join, this is a very necessary functionality!

[teroblepuns]

Left on read for 6 years... I need this feature so much rn, it would save so much time