Search Unity

Collider limit in PhysX 3.3

Discussion in 'Physics' started by TheJ, Apr 16, 2015.

  1. TheJ

    TheJ

    Joined:
    Apr 15, 2015
    Posts:
    2
    I spoke to Unity about the physics problems we’re seeing, where the physics system stops working after a large number of colliders. They spoke to nvidia and it turns out there’s an undocumented limitation of 262k colliders in PhysX 3.3. This is apparently fixed in PhysX 3.4, but Unity has no plans to make that upgrade.
     
    TheJ, Apr 16, 2015
    #1

  2. yant

    yant

    Unity Technologies

    Joined:
    Jul 24, 2013
    Posts:
    596
    Hello,

    I think you've been provided with the answers on the other thread, but let me just add my 2c:

    - Unity 4 had a limitation of 64K for colliders in scene
    - Unity 5 raises this up to 260K (+300% improvement)
    - Unity 5 comes with PhysX 3.3, which is the latest PhysX up to date
    - PhysX 3.4 is not out yet
    - We're considering a backport of that fix from PhysX 3.4 to PhysX 3.3, just to make it available sooner than we update to 3.4

    Should you have any further questions don't hesitate to ask.

    Hope this helps.

    Anthony
     
    yant, Apr 16, 2015
    #2
    BTables and hippocoder like this.

  3. artur_hartikainen

    artur_hartikainen

    Joined:
    Apr 10, 2017
    Posts:
    3
    Hello,

    So what is current situation with colliders in Unity? Is it still limited to 260K?
     
    artur_hartikainen, Mar 10, 2018
    #3

  4. Alex33333333

    Alex33333333

    Joined:
    Jan 3, 2017
    Posts:
    11
    Hi! Is there any warning or some action from unity when collider limit is reached? I had spawned 700k cubes with colliders and everything seemed to be working good. I had tested it on 5.6.1p3 and 5.2.1f1. Is this restriction applies to box colliders or mesh colliders or maybe colliders with unique mesh?
     
    Alex33333333, Mar 10, 2018
    #4

  5. jwvanderbeck

    jwvanderbeck

    Joined:
    Dec 4, 2014
    Posts:
    825
    Unity 2017.3 still running into the 262k limit on colliders :( This really throws a wrench in the design of our editor tools which use those colliders.
     
    jwvanderbeck, Mar 16, 2018
    #5

  6. yant

    yant

    Unity Technologies

    Joined:
    Jul 24, 2013
    Posts:
    596
    So this limit is mostly visible when running queries. E.g. a sphere cast will miss some of the colliders because the spatial search tree can only accommodate up to 260k colliders. As I said before, this limitation is removed in PhysX 3.4 that will hopefully be rolled out after 18.2 later this year. Hope this helps.
     
    yant, Mar 26, 2018
    #6
    Antypodish likes this.

  7. jwvanderbeck

    jwvanderbeck

    Joined:
    Dec 4, 2014
    Posts:
    825
    Actually after the limit is reached, it appears we are unable to even create the components anymore.

    After 18.2? So you mean 18.3 at the earliest, or end of this year? Ouch.

    We might have to invest in writing our own scenegraph :(
     
    jwvanderbeck, Mar 26, 2018
    #7

  8. RisingMos

    RisingMos

    Joined:
    Aug 28, 2015
    Posts:
    17
    I wish we would start to see it in 18.2 as an experimental feature. Or at least have an separate build for it.
     
    RisingMos, Apr 2, 2018
    #8

  9. yant

    yant

    Unity Technologies

    Joined:
    Jul 24, 2013
    Posts:
    596
    yant, May 23, 2018
    #9