[ODE] Joint Question

[Remi Ricard]

Hi David,

> I'm trying to simulate a "pin joint".  In this scenario, one body has
> a hole through which another body spins:  this is shown below in an
> exquisite ASCII figure.
>            ___________
>           /   ____   /   /
>          /   /     /  /   /
>       ********/  /   /*****
>        /   -----  /   /
>       /---------/--/
> 
> The line of stars should rotate around the central axis running
> through its length.  The rectangular torus should not be transformed
> by this rotation.
> 
> I tried implementing this with a hinge joint, but there is no anchor
> point between the bodies.  The only joint type that does not require
> an anchor point is the slider joint, which allows a degree of
> translational freedom instead of rotational freedom.


I created a "Piston" joint. It is a joint like the ODE slider joint with
no restriction for the rotation along the sliding axis. (I don't 
remember if this joint is fully tested).

The problem is I'm going in vacation soon so I'm not able to create a 
patch (too much work before the vacation). What I can do if you are 
interested is to send you my joint.cpp file.

Remi