Question Best approach for scaling collider

As part of the software I'm developing, I need to allow users to change the uniform scale of objects at runtime, and have the colliders be scaled/regenerated with the mesh (similarly to how this would work when scaling a gameobject in unity). I had a little try with this a while ago, and the collider seemed to scale with the rendermesh when it was a sphere, but not when set to a convex hull.

Only a few objects will be scaled at a time, so I'm not worried about having the collider scaling be fast.

Is there currently a way of doing this, ideally without using unsafe code? Thanks for any advice.

 

as far as i know when changing colliders you need to recreate the collider and the physics mass components
there is some way using unsafe code to change the collider size, but you are entering grey area

 

There is a regular way to do it, but it does involve a bit of "unsafe" code and it depends on the collider type. For some collider types (like BoxCollider) you just need to change the collider's geometry and update PhysicsMass: https://forum.unity.com/threads/resizing-colliders-at-runtime-and-in-jobs-with-burst.1056695/
ConvexCollider is harder, I'd recommend re-creating it from scaled points.

 

I'm thinking that it might be wise to delay this feature in my project until the very end in the hope that Unity adds a safe and performant way of doing it before release.

 

We will be looking into this in the coming releases. No concrete timelines yet, but it's high on our list.