I have a simulation and know the inertia tensor of all the rigid bodys simulated with it.

So I have two questions:

1.: Can I set the inertia tensor Bullet uses for calculations?

2.: What exactly does "getInvInertiaTensorWorld" return i.e. is the tensor rotated like the rigid body is,

does the "Inv" mean the Matrix is inverted and how does Bullet determine it in the first place?