Collisions and overlaps

BeginPlay gotchas §

If you have an overlapping component which needs to trigger BeginOverlap, it might not work on actors which are spawned on the same frame as the component’s BeginPlay fires.

For some reason GetOverlappingComponents will not return the spawned actor.

Workaround: Set a timer for the next tick and run the logic there.

Hit events §

Send hit events is called SetNotifyRigidBodyCollisions in C++.

//you can set the value like this
MyPrimitive->SetNotifyRigidBodyCollisions(true/false);
 
//you can read the value like so
MyPrimitive->GetBodyInstance()->bNotifyRigidBodyCollision

This affects hit events from collisions during physics simulation. Hit events can trigger with this off from things like sweeping movement or character movement component collisions.

Other collision gotchas §

Overlaps with GetOverlappingActors do not trigger if the actor doing the overlap check has “Use complex as simple” set as its collision option.