[ODE] Using rays as sensors

[Megan Fox]

Please look at the documentation - specifically, what you're doing
when you set the ray's direction.  This sets the BODY'S direction as
well.  To set the direction of the ray independently from the
direction of the body, attach a dGeomTransform inbetween the body and
the ray.

-Megan Fox

> But as soon as I do my first Worldstep, my ray's direction as changed.
> If i do a dGeomRayGet... the direction is (0,0,1) >> the ray that was set to
> look in a direction in the (X,Y) plan is now looking up.
> The direction as changed, but not the position.
> 
> So, what the hell is wrong ?
> For me a ray is a geom like others so I dont want to have to set the direction
> at each frame. It shouldnt change (in the local axis).