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Lightmap blotchesn in Unity 2018.2.10f1

Discussion in 'Global Illumination' started by millefoliumink, Oct 9, 2018.

  1. millefoliumink

    millefoliumink

    Joined:
    Aug 28, 2014
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    I have a very basic FBX corridor which is about 15m x 9m, I set generate lightmaps when importing the model in, and I'm lighting it with FBXs with an emission material applied.

    I have the settings below and have tried the default settings for lightmapping but I keep getting the same result.

    Not sure what I'm doing wrong, help please?

    https://imgur.com/a/fE5ulQg
     
    millefoliumink, Oct 9, 2018
    #1

  2. JenniferNordwall

    JenniferNordwall

    Unity Technologies

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    Sep 19, 2016
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    Hi

    Seems like you have a big noise problem in the scene and I will try to help you but I need some more information. What type of light sources are you using? The scene seems very basic and don't think that high resolution is needed. Maybe try 40 to begin with.

    You also said that you tried with default settings, how was the result then? Better or worse?

    I did a talk earlier this year https://www.gdcvault.com/browse/gdc-18/play/1024840 which brings up the settings of the Progressive lightmapper, and I suggest that you might have a look. Only 20 min and it will bring up noise, sample count and filtering.

    Cheers!

    Jennifer Nordwall,
    Lighting Team, Unity
     
    JenniferNordwall, Oct 9, 2018
    #2

  3. millefoliumink

    millefoliumink

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    Hi thanks for your reply. I've used the Progressive Lightmapper before on a far more complex project, the only difference this time is the newer version of Unity (previous was 2017) and nothing seems to be making a difference.

    The light sources are GameObjects with Emission on their Materials (Global Illumination set to Baked).

    Here is an example with one light source using Standard Unity shader with Emission and Progressive Lightmapping on Default settings:
    https://imgur.com/a/Pnx3tLI

    Here's an example using Unity primitives:
    https://imgur.com/a/h0gxAMT


    The issue doesn't appear to be my FBX model or import setting, as you can see the issue still persists :/
     
    Last edited: Oct 9, 2018
    millefoliumink, Oct 9, 2018
    #3

  4. JenniferNordwall

    JenniferNordwall

    Unity Technologies

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    Hi

    So in the talk I do mention some issues we have with sampling tiny emissives. We sample them using the indirect samples (random on a hemisphere), which have low probability of hitting that small emissive surface. So my first suggestion would be to use small area lights instead (would be much faster since they will use the direct samples). Alternatively you could increase your indirect samples and try some different indirect filtering settings, or switch to Enlighten.

    This issue is something that we are working on, but I cannot give you an ETA.
     
    Last edited: Oct 9, 2018
    JenniferNordwall, Oct 9, 2018
    #4

  5. millefoliumink

    millefoliumink

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    Hi, could you clarify if this is a 2018 specific problem and how tiny you mean by tiny? I lightmapped this way in 2017 with no problems.

    Enlighten produces it's own problems, size does not appear to influence the quality of outcome in regards to blotches, image below

    https://imgur.com/C9z58XL

    Also I'm not using an Area Light, I am using an Emissive Material. Filtering Settings don't influence any chance in Progressive or Enlighten, the result is just as blotchy.
     
    millefoliumink, Oct 9, 2018
    #5

  6. JenniferNordwall

    JenniferNordwall

    Unity Technologies

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    Sep 19, 2016
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    Hi

    Can you please try to use an area light instead? And filtering settings is not a thing in Enlighten, since it is built on different tech.

    What you have is a lot of noise on a very non complex scene. Did you have a look at my talk about the different settings in Progressive, and maybe somehow can tweak filtering and sample count to get the noise down?

    And where you able to light this scene, in this exact same way in 2017 without this issue? If you, you should file a regression bug.
     
    JenniferNordwall, Oct 10, 2018
    #6

  7. Pancar

    Pancar

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    Pancar, Oct 16, 2018
    #7

  8. AcidArrow

    AcidArrow

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    Reduce lightmap resolution a lot and increase indirect samples a lot.
     
    AcidArrow, Oct 27, 2018
    #8