[ODE] rotating spheres (planets)

[Geoff Carlton]

What you are trying to do is well outside the scope of most of our 
applications for ode, and I think whether the pebble/spaceship would 
spin with the planet is going to be the least of your problems.

For a start, ode doesn't simulate drastic differences of mass 
particularly well, nor drastic differences in size.  If you wanted to 
simulate a planet as a physics body, how are you going to do it?  Using 
a simple sphere won't cut it if you really want a space ship interacting 
with it - what about mountains etc.  Perhaps you need a spherical 
terrain, which you would have to create yourself.  What geom do you need 
for a spaceship - a box, a sphere, a trimesh?  Do you need the planet as 
a physics body, reacting to forces?  How about lodding, can you simulate 
an entire system's worth of objects at once?  What about every other 
object on the planet you will want the spaceship to interact with?  Will 
the precision be up to the task of simulating everything from a solar 
system down to a pebble?

If you examine the mailing list you will see that this concept is far 
removed from pretty much anything else being done at the moment, but 
good luck to you if you want to give it a go yourself!  You'll probably 
find as you tinker around with ode you'll come up with more specific 
problems that are easier to answer.

Geoff