BEPUphysics

Reporting a bug,

I set the terrain collisionrules.group to a specific collisiongroup. In the event collision callback, the other.Entity.collisionRules.group (this is the terrain) is null.

With which event type did it happen, and what sort of actions were being performed at the time of the error?

EventHandlerInitialCollisionDetected

I was just reading it's Entity.collisionRules.group to compare.

I setup the Terrain with a collisionRule group

Terrain terrain_;
terrain_.collisionRules.group = collisionGroup; //this s a new CollisionGroup I pass in, non null)
Space.add (terrain_);

I am unable to replicate the error; is it rare or erratic? A repro case would help.

Ahh. I got the reason. I wasn't testing the Entity.collisionRule directly but the Entity.tag collisionRule. For the terrain, the tag is tied to a dummy Entity that has noPair.

My bad, apologies.