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Groups not working

Discussion in 'DOTS Physics' started by snacktime, Jul 21, 2021.

  1. snacktime

    snacktime

    Joined:
    Apr 15, 2013
    Posts:
    3,305
    Really odd colliders that return true for CollisionFilter.IsCollisionEnabled won't collide. Layers have values but are not set to collide, colliders have the same >0 group index.

    Except they do collide when using Havok.

    Doesn't seem to matter how I create the collider, conversion or manual.

    I am using sub scenes, and the colliders are by default prefabs from the sub scenes. I tested with just replacing the colliders on instantiation with manually created ones to see if that made any difference but it didn't.

    Sort of at a loss, what seems likely to cause this?
     
    Last edited: Jul 21, 2021
  2. snacktime

    snacktime

    Joined:
    Apr 15, 2013
    Posts:
    3,305
    Seems to me like group unions might be a possible issue during broadphase filter combining? I don't have a completely clear picture of possible parent/child nodes and where all the combined filters for those are used. Like is it possible for a parent to have children that have different group indexes? If so wouldn't that just set all the children to 0?

    It does seem like it's the combined filter being wrong that is the issue. Especially since it always works in havok, and what else could it even be?
     
  3. papopov

    papopov

    Joined:
    Jun 29, 2020
    Posts:
    21
    Hey, which version of Unity/Havok physics are you using?
    Also, could you share with us the troublesome CollisionFilter values that don't work for you?
     
  4. snacktime

    snacktime

    Joined:
    Apr 15, 2013
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    2020.3 LTS and 0.6.0-preview3.

    Filter I described, same group index > 0. I verified all possible combinations that IsCollisioEnabled handles just to rule out scenarios like maybe havoc was colliding with any positive group index combination. But havoc worked correctly in all cases.

    Just to be clear this is Unity.Physics not working correctly.
     
  5. steveeHavok

    steveeHavok

    Joined:
    Mar 19, 2019
    Posts:
    480
    Just to make things clear and easy, do you have an example scene showing the problem?
    There have been a few changes to the composite collision filters, and there are a number of other elements that could contribute to the issue. I'd really like to be on the same page when discussing the problem.
     
  6. snacktime

    snacktime

    Joined:
    Apr 15, 2013
    Posts:
    3,305
    I did but don't anymore. I abandoned the group approach for other reasons entirely.
     
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