[ODE] Geomgroups vs composite

[skjold@cistron.nl]

> Here's a patch that fixes a few things relative to your
> version of test_boxstack.cpp

Thanks! Yep, I use a release build of ODE, so I never noticed that position and orientation was being queried illegally for planes.


> 
> [*] This does seem to suggest that there should be a supported
> way of asking whether a given geom type is placeable, rather than
> 'knowing' about the nonplaceable set ahead of time.  Russ?  I'd
> be willing to submit an interface for this, it seems pretty trivial.

If I remember correctly, I saw a similar request in the mailing list archive (must be from februari or januari, I think). So, chances are that this change is on its way :)

Also I'd like to request (again - just to be sure :P) the possibility of setting/getting userdata on spaces. I would be willing to make that change in ODE, but since I'm still rather new to this I don't have the necessary insight into ODE internals yet, and I don't use cvs yet either. Anyway, I figure that spaces will be used to contain the geoms for articulated bodies (or composites, or any other logical group of geoms), so it would make sense to set that custom userdata pointer for each space to the app-specific data it represents. I hope this makes sense, that I'm not thinking in the wrong direction :P