rigid body physics in Blender (was Re: [Bf-committers] SOC idea)

[Willian Padovani Germano]

Hi Erwin,

Should have emailed you already about this. You probably know that 
integrating ODE in Blender has been in the plans for some time (and 
available in experiments via Python probably for longer than that).

I've made some quick tests a couple months ago, been reading ODE mailing 
list archives and the BULLET forum and now and then we discuss a little 
about it during irc meetings. Now I should have time to try to code it 
properly, using groups to define spaces, possibly adding a new type in 
Blender to represent joints, etc.

 From what I've gathered (specially from your posts to the mentioned 
list and forum), it seems it would be desirable to have both ODE and 
BULLET integrated in Blender, at least with BULLET as alternative for 
ODE's  collision detection (you released ODE with BULLET support some 
months ago, from what I recall). We can also have both as alternatives 
for dynamics, you're obviously the right person to opinate about that.

So, in short:

- Integrating rigid body dynamics in Blender directly is a current and 
"approved" project.
- There are coders interested, experimenting in C or Python with ODE.
- A C API for BULLET is a welcome addition, for sure.
- The details have not been decided yet: if rigid body should become an 
object constraint (Ton's informal suggestion), modifier or be independent.
- I'd like to know your opinions about the integration: ODE + BULLET?

As I said I'm interested and working on the ODE side and it's great to 
see you interested in working on physics in Blender, too. Unless you 
prefer to code it all yourself "in one go", I and probably others here 
would enjoy participating.

Finally, as Ton frequently points, properly integrating rigid body 
physics with particles,  softbodies, cloth, and the rest of the 
animation system is also an important goal.

This seems to be a good time to discuss / coordinate efforts, so others 
interested please say so, too.

Erwin Coumans wrote:
> In that case it would be useful to integrate Bullet collision detection 
> / physics more tightly into Blender (independent from the Game engine).
> With some performance improvements it would be very useful for 
> 'advanced' particles too. I can easily add a C-API to it (to avoid C++ 
> hassle).
> 
> I would like to do this, but need someone who helps pointing out the 
> hooks in Blender. Would it be a rigidbody 'modifier'?
> Erwin

--
Willian