Toggle IsSensor after body is added to physics system

[SSNTails]

I hope I am not being annoying and find it at least slightly entertaining the ways I'm trying to break Jolt. :)

When I set body.SetIsSensor(true) after it has already been added to the physics system (and some simulations have potentially already run), I get an assert failure at:

JoltPhysics/Jolt/Physics/Collision/CollisionDispatch.cpp

Line 23 in 0191c72

JPH_ASSERT(false, "Unsupported shape pair");

This is the code that causes the assert failure:
JPH::BodyLockWrite lock(mPhysicsSystem->GetBodyLockInterface(), object->collisionObjectID); if (lock.Succeeded()) { JPH::Body &body = lock.GetBody(); body.SetIsSensor(isSensor); }

Is this simply not supported? What would be the solution, to remove the body from the scene and re-insert it? I tried doing so (please try to not bang your desk against the desk at my crazy code), but it still results in the same assert error:

`
void CollisionHandler::SetAsSensor(WObj::WObj *object, bool isSensor)
{
if (object->collisionObjectID.IsInvalid())
return;

bool doSwap = false;
{
	JPH::BodyLockWrite lock(mPhysicsSystem->GetBodyLockInterface(), object->collisionObjectID);
	if (lock.Succeeded())
	{
		JPH::Body &body = lock.GetBody();

		if (body.IsSensor() != isSensor)
			doSwap = true;
	}
}

    // Gotta scope all of these locks properly so we don't get double-locking...
if (doSwap)
{
	JPH::BodyInterface &bi = mPhysicsSystem->GetBodyInterface();
	bi.RemoveBody(object->collisionObjectID);

	{
		JPH::BodyLockWrite lock(mPhysicsSystem->GetBodyLockInterface(), object->collisionObjectID);
		if (lock.Succeeded())
		{
			JPH::Body &body = lock.GetBody();

			body.SetIsSensor(isSensor);
		}
	}

	bi.AddBody(object->collisionObjectID, JPH::EActivation::Activate);
}

}
`

I am trying to change the IsSensor flag on a kinematic triangle mesh, btw. This appears to work fine when I use a convex hull instead. Bug or intentional?

[jrouwe]

Your error means that you are now trying to (probably) collide a mesh with a mesh which is not supported. Make sure that your mesh sensor is not in a layer that collides with other meshes.

[SSNTails]

D'oh, you are absolutely right, I should be creating my moving triangle meshes on a layer separate from the dynamic ones. 🤦‍♂️ While it can be frustrating sometimes, I appreciate all of the asserts you've added to the library to make sure people are doing things right.