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Question Unity 6 changed physics engine?(Into PhysX) and now it's really buggy?

Discussion in 'Physics' started by ClosingTime, May 16, 2024.

  1. ClosingTime

    ClosingTime

    Joined:
    Nov 23, 2016
    Posts:
    278
    What used to work in Unity 2023, now is getting crazy in Unity 6.
    It seems like ragdolls behave really weird.
    Specifically, I am trying to have a situation where I use impulse force on a ragdoll to simulate a kick.

    However, the ragdoll doesn't seem to respect angle limitations on bones. In additions, bones seems to stretch out of the joints, and do crazy things.

    Is this a bug in the new Unity 6?

    Could it be that Unity 6 now force PhysX and that's how PhysX works?
     
  2. Ryiah

    Ryiah

    Joined:
    Oct 11, 2012
    Posts:
    21,937
    What do you mean "force"? It's always used PhysX for 3D.
     
    arkano22, spiney199 and Spy-Master like this.
  3. halley

    halley

    Joined:
    Aug 26, 2013
    Posts:
    2,661
    I did notice changes from 2022->2021, where the "automatic center of gravity" didn't quite behave the same. But I haven't seen similar changes from 2022->2023/6 in the limited testing I've done there.
     
  4. yant

    yant

    Unity Technologies

    Joined:
    Jul 24, 2013
    Posts:
    597
    Hey!

    There are some massive changes internally going into Unity 6 and beyond. Let me confirm it's still PhysX, like it used to be for years before. However, maybe, something was lost in the refactoring processes, I'll check with the team. Any chance you have a repro, or a reported bug#? Thanks.

    A
     
    laurentlavigne likes this.
  5. mgear

    mgear

    Joined:
    Aug 3, 2010
    Posts:
    9,566
  6. zezba9000

    zezba9000

    Joined:
    Sep 28, 2010
    Posts:
    1,004
    Physics is also totally broken for me as well.
    With AnticulationBody specifically.

    * Convex MeshColliders no longer work

    * Also maybe something wrong with "SetDriveForceLimit" or "ArticulationBody.transform" no longer updates transform in FixedUpdate


    I upgraded from Unity 2022.3 which was working perfectly.
     
  7. arkano22

    arkano22

    Joined:
    Sep 20, 2012
    Posts:
    2,063
    Physics are indeed broken in all sorts of ways in Unity 6: joints, rag dolls, articulations, and sometimes even basic rigidbody behavior have ceased to work properly.

    Will try and send bug reports for each specific issue.
     
  8. blockman8888

    blockman8888

    Joined:
    Jun 17, 2024
    Posts:
    26
    Reset physics button is gone in unity 6000.0.5 for the project settings also please get rid of this limitation as it should have been fixed for years now: Couldn't create a Convex Mesh from source mesh, within the maximum polygons limit (256). The partial hull will be used. Consider simplifying your mesh. Source mesh name:

    Also is real time fluid simulations physics can there be a revolutionary system that will allow for 10s of millions for particles that can collide with still super fast frame rates