[ODE] Using rays to generate a light/shadow map

[John Miles]

Even after you've solved your present difficulties, you still won't be able
to use ODE / OPCODE's rays for anything lighting-related.  They don't
collide reliably with triangle edges.

-- jm

> A peculiar turn of events:
>
> I did some deeper investigation and was able to determine that my code
> was at fault, in one way at least. It was generating incorrect x,y
> positions on the map for use in casting the rays. So, fine, I fixed it.
> Now, things get weird.
>
>