Is it possible to tell Unity physics to ignore a collision at collision time?

I have some rigidbodies bouncing around and colliding with each other using standard Unity physics. However, in some cases (like if one rigidbody is moving fast enough), I would like for one rigidbody to destroy the rigidbody it collides with and then continue moving without bouncing, effectively ignoring the collision. The check for this case should only happen at the actual time of collision. I’m having some trouble figuring out how to do this efficiently.

I’ve tried putting the check in my OnCollisionEnter. If this check is true, then I Destroy the second rigidbody. I’ve also tried calling Physics.IgnoreCollision() at that point. However, in both cases, the first rigidbody still bounces (presumably because the physics collision happens before OnCollisionEnter is called).

Is there a way to make this work?

The only solution I’ve been able to come up with is by putting two colliders on each rigidbody - the current collider I already have, and then a second trigger collider just slightly larger than the first collider. Then, I could destroy the rigidbody OnTriggerEnter before the collision happens. But this all feels wrong and kinda hacky. It also seems like this would fail if the speed was fast enough.

It sounds like you might want to do this backwards - that is, use triggers for everything, and then, in the OnTriggerEnter(), decide if you want to resolve the collision or remove the object. The only issue is that you would have to resolve the collisions yourself. But depending on the shape of the objects being used, that might not be very complicated.

The only other thing I could think is to do the collider/trigger swap before any collision. For instance, if a rigidbody is moving above a certain speed, make it a trigger, and destroy any objects that enters it. That way, it effectively ignores collisions.

Hope that at least gave you some ideas to work with.