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Black spots with Precomputed Realtime GI

Discussion in 'Editor & General Support' started by newmonuments, Aug 21, 2015.

  1. newmonuments

    newmonuments

    Joined:
    Oct 21, 2014
    Posts:
    15
    Certain elements in my scene have black spots associated with the realtime precomputed GI. How do I fix this?

    Here is the background info:
    1. When I bake lighting, these do not appear. They always appear with precomputed gi
    2. I have custom created lightmaps for all effected objects in Maya and "preserve UVs" is checked.
    3. These black patches are not shadows, as there ARE shadows that look quite different and behave properly as the direction of light moves around (the black spots also move as the lighting moves around, but it is clearly not like a shadow).
    4. Increasing precompute resolution helps to a certain point, and then it doesn't. Increasing cluster resolution to 1 helps some.

    I am posting images of the artifacts and my lighting settings as well as the lightmap settings for the columns (which you can see affected by the black splotches in the image)
    light problem.JPG
    light problem 2.JPG light settings 1.JPG column lightmap settings.JPG
     
  2. Carpe-Denius

    Carpe-Denius

    Joined:
    May 17, 2013
    Posts:
    842
    Looks like overlapping uv2. Try unity generated uv2 and see if the spots disappear.
     
  3. newmonuments

    newmonuments

    Joined:
    Oct 21, 2014
    Posts:
    15
    I tried setting it to Unity generated UV2 in import settings, and the black splotches become more prevalent.

    All verticies of the UV2 are snapped to the grid in Maya, so I can't seen why there would be problems with the UV2. Additionally, the baked lightmap doesn't have this problem, so why would it appear with the precomputed GI?

    Any thoughts?
     
  4. newmonuments

    newmonuments

    Joined:
    Oct 21, 2014
    Posts:
    15
    So I've unchecked static on the columns, which seems to help. Since it only does realtime light and not precomputed realtime (with bounces) it doesn't use the messed up lightmaps (which work perfectly for bakes, just not precomputed...).

    I'm still having issues with items that I can't uncheck "static" on for other reasons.
    See the bottom corner of the wall here, and the light fixtures. Note that Ambient light, and baked light are combining with precomputed so that the artifacts are less noticeable. When it's only on precomputed with no bakes and no ambient, the artifacts are totally black.
    black patch.JPG black patch 2.JPG

    black patch.JPG
     
  5. newmonuments

    newmonuments

    Joined:
    Oct 21, 2014
    Posts:
    15
    Anyone? This is a catastrophic problem for realtime lighting...
     
  6. Carpe-Denius

    Carpe-Denius

    Joined:
    May 17, 2013
    Posts:
    842
    Could you upload your scene somewhere?
     
  7. newmonuments

    newmonuments

    Joined:
    Oct 21, 2014
    Posts:
    15
    Ok, so it looks like switching to Directional from directional spec gets rid of the black patches.... but I want specular info, so what should I do?

    In the meantime I'm preparing a simplified version of the scene to upload.
     
  8. angeliapayne

    angeliapayne

    Joined:
    Jul 13, 2012
    Posts:
    30
    BUMP. I am having this same issue with Directional Realtime GI....Regardless of whether or not I check Preserve UV's, increase the irradiance budget and quality, or adjust any other of the lightmap settings for my affected objects.
    NewMonuments - have you learned anything new on this issue?

    Why are some faces black after running Precompute GI?????? Can I edit this at all??? Unity 5.3.2p3.