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Upgrading to 2020.3 broke lightmaps

Discussion in 'Global Illumination' started by JohnnyFactor, Nov 20, 2021.

  1. JohnnyFactor

    JohnnyFactor

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    May 18, 2018
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    343
    I have a project that I upgraded from 2019.4 to 2020.3 and the baked lightmaps broke. It looks like the lightmap UVs are messed up but no changes were made to the project. Did something change with 2020.3? Can I get the old UVs back without rebaking everything?
     
    JohnnyFactor, Nov 20, 2021
    #1

  2. kristijonas_unity

    kristijonas_unity

    Unity Technologies

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    Feb 8, 2018
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    This is a known limitation of our current upgrade path. Unfortunately, when upgrading between major releases, chances are that your lightmaps will be corrupted, requiring you to rebake. This is something that we are planning to look into in the future. Sorry about any inconvenience.
     
    kristijonas_unity, Nov 22, 2021
    #2
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  3. AcidArrow

    AcidArrow

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    If you want to more reliably be able to upgrade without the UVs getting messed up, you need to generate your own lightmap UVs for each of your meshes. As a bonus you will have much nicer UVs, since Unity's generator is kinda bad, but it's a decent amount of work.
     
    AcidArrow, Nov 27, 2021
    #3
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  4. JohnnyFactor

    JohnnyFactor

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    Good advice. This project used a ton of clipart and at some point, I just got lazy and starting hitting the 'auto uv" button. Seems like it came back to bite me.
     
    JohnnyFactor, Nov 27, 2021
    #4

  5. UnityLighting

    UnityLighting

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    UnityLighting, Nov 30, 2021
    #5
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  6. pokerFace

    pokerFace

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    Mar 26, 2013
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    Sorry for bringing up an old topic.
    Please tell me, is there a way to manually somehow transfer the settings of the light maps from the old version to the new one, so as not to re-bake again?
     
    pokerFace, Dec 27, 2022
    #6

  7. AcidArrow

    AcidArrow

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    If the lightmaps broke because of the mesh generated UVs broke, then I don't think there is an easy way. If it broke because of the atlasing, then it's more easily redeemed.

    With both methods you'll be fighting against Unity though, so you might as well give up and rebake your lightmaps.
     
    AcidArrow, Dec 27, 2022
    #7