[ODE] OT: Tumbling

[Martin C. Martin]

Russ Smith wrote:

>>When there's no net torque on an object, its angular momentum is 
>>conserved.
> 
> true.
> 
>>The axis it rotates about is constant.  But is it constant 
>>in body coordinates, or world coordinates?
> 
> the axis of rotation is not constant,

Thanks for the tip Russ.  I had assumed this was like the linear case, 
where it reduced to a purely kinematic question, but of course it isn't. 
  The angular momentum is constant is world coordinates, but the moment 
of inertia is constant in body coords, not world coords.

I read Baraff's tutorial, now I've figured it out.  Thanks.

- Martin