Search Unity

Should it be possible to edit a PhysicsMaterial asset at runtime and see the change live?

Discussion in 'Physics' started by Xarbrough, Sep 12, 2019.

  1. Xarbrough

    Xarbrough

    Joined:
    Dec 11, 2014
    Posts:
    1,188
    I have a PhysicsMaterial2D applied to a few colliders in my scene and tried to tweak the friction and bounciness values at runtime. However, I quickly noticed that the values are not reflected in the live simulation. Instead I needed to disable and re-enable all colliders or restart play mode to see the changes.

    I understand that this may be a limitation of communicating with the physics middleware, but it could also be a bug, so I wanted to ask in the forum.

    If this is intended behavior I would like to suggest to show a small info text on the PhysicsMaterial2D inspector when in play mode, e.g. "Changes made in play mode will only be applied when affected colliders are toggled.".
     
    Xarbrough, Sep 12, 2019
    #1

  2. MelvMay

    MelvMay

    Unity Technologies

    Joined:
    May 24, 2013
    Posts:
    11,459
    No, this isn't a live asset that is read each simulation step. If you change it you'll need to reassign it, no need to disable/enable the collider.

    It's a frustrating limitation that would require a significant change to Box2D to get this working. So far it's not been a high priority but I understand it's kind of annoying.

    In the meantime I'll look at updating the docs and making the behaviour more obvious.
     
    MelvMay, Sep 13, 2019
    #2
    Xarbrough likes this.