[ODE] how to glue bodies together ?

[Martin C. Martin]

>>I tried to use fixed joints but the results are unreliable (as it's
>>written in the latest doc). 

Looking at the latest doc, it doesn't say it's unreliable at all.  It 
says to avoid it, probably because it's slow, and the fixed joint may 
come apart a small amount, as any joint does.  Nate's suggestion of 
combining the bodies removes both those problems.

Can you explain what you mean by "unreliable"?

> Don't combine the bodies.  Instead, just use one body - combine the
> geoms, and combine the masses so it acts like both bodies.

This gets tricky when you have a object that you want to break apart or 
join together at some point.  While it's possible to create/destroy 
bodies and geoms when that happens, that's a PITA.  In some 
applications, the problems of using a fixed joint may be small.

Now that I think about it, maybe a function to "join" two bodies/geoms, 
and another one to split them, would be useful?

- Martin