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Feature Request better auto UVs

Discussion in 'Global Illumination' started by PutridEx, Apr 4, 2022.

  1. PutridEx

    PutridEx

    Joined:
    Feb 3, 2021
    Posts:
    1,136
    I feel I've blamed my bake quality for a long time on the lightmapper itself, but I'm starting to think it's the auto UVs causing the issues. There's always issues with auto UVs for me with unity's lightmapper.
    Bakery solved this issue, and I feel like it's auto UVs are much better which leads to a much much higher level of quality and honestly less struggles and frustration. I think this should be the priority for unity's GI team to handle.

    I could be wrong here, but if what I'm saying is right, this would make life a lot easier.
     
  2. AcidArrow

    AcidArrow

    Joined:
    May 20, 2010
    Posts:
    11,792
    I think the wise decision here would be to give up on generating lightmap UVs.

    1. The UV generation algorithm was "ok" 10 years ago. I think we can consider it bad now (and it has actually gotten worse with time).
    2. It still has cross-platform issues. Open the same project on a Mac (or a different brand CPU) and the UVs might generate a bit differently on import, making your Lightmaps invalid. (this was partially addressed by Alexey in the Unity 3-4.x days, but hasn't been touched since AFAIK and it's one of those things that need to be at 100% to not be an issue).
    3. If they start tweaking it, upgrading to a new Unity version will also invalidate your lightmaps. Unless of course they change how it works (and the generated UVs are stored somewhere so they don't have to be generated if you aren't baking new lightmaps), but I wouldn't hold my breath.
    4. For whatever reason, the lightmapping team has had other priorities for many years. It took them a couple of years to fix serious regressions in the way the islands are packed (and they still haven't fixed all of them...) (related link: https://forum.unity.com/threads/packing-continues-to-be-horrible-please-fix.453014/ )

    At this point, I can't imagine them addressing all the above in one fell swoop, and if they don't address them all, then the feature is not reliable enough to be worth using. Make your own UVs. I use Rizom UV, it's good.

    Only use UV generation for throwaway UVs while you are still changing things a lot. Once your levels start stabilizing a bit, make UVs manually.
     
    Last edited: Apr 5, 2022
    PutridEx likes this.
  3. rasmusn

    rasmusn

    Unity Technologies

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    Nov 23, 2017
    Posts:
    103