Re: [eigen] Eigen and rigid body simulation

[Mathieu Gautier <mathieu.gautier@xxxxxx>]

> If that happened, would you still want to have this stuff in Eigen or
> would your rather use KDL for that? Since you were able to reformulate
> above everything in terms of Lie algebra and without any mechanics, it
> seems like this is now really interesting to have in Eigen,
> independently of the particular use case you had in mind, but I also
> don't want to do it if its main author (you) is going to not use it in
> the future because KDL does it!

I think that these elements have to be in Eigen. Actually, I'm speaking 
with Maxime Tournier who had an interesting implementation of such 
elements. Basically, he has some classes describing Lie groups and Lie 
algebras and their operations. They are specialized for certain type :

struct Lie<Quaternion> 		  <- rotation3D
struct Lie<Matrix<Scalar, 1, 7> > <- 3d direct isometries (maybe Matrix 
is not a good choice)

This approach is interesting, since it describes the group structure.

so, the definition I proposed may change to better reflect the 
geometrical aspect of these elements.

--
Mathieu