[eigen] Re: Rigid transformations in eigen: use of dual quaternions

[Rohit Garg <rpg.314@xxxxxxxxx>]

Any particular reason why eigen does not support expressions like
s1*q1+s2*q2 where s1 and s2 are scalrs and q1 and q2 are quaternions?

Here is a tiny patch for quaternion.h to add them,

I would have committed it to my branch and pointed you to it, but I am
having trouble with hg behind proxy once more. So please commit this
(I mean to eigen mainline  unstable branch!).

On Sat, Sep 12, 2009 at 6:17 PM, Rohit Garg <rpg.314@xxxxxxxxx> wrote:
> Hi,
>
> a) What is the internal representation of affine transformations
> (excluding scaling) in eigen?
>
> b) I am right now rolling my own dual quaternion class, but if eigen
> provides dual quaternions (say as RigidTransform class, to exclude
> scaling) then it would be very useful indeed.
>
> c) Dual quaternions have many advantages, in that they allow artifact
> free skining, rigid transform interpolation, are resistant to
> numerical defects (just like quaternions). Was their use considered
> and discarded?
>
> d) The recently introduced EIGEN_TRANSFORM_PLUGIN, what does it do?
>
> e) Interpolation is the key thing here. We need it and we are having
> to do it ourselves. But we'd like to have the code rolled into eigen,
> so that it plays nice with the rest of the geometry api and allows
> convenient extraction of matrices (to upload as uniforms to shaders).
>
> --
> Rohit Garg
>
> http://rpg-314.blogspot.com/
>
> Senior Undergraduate
> Department of Physics
> Indian Institute of Technology
> Bombay
>



-- 
Rohit Garg

http://rpg-314.blogspot.com/

Senior Undergraduate
Department of Physics
Indian Institute of Technology
Bombay

Attachment: quat_patch
Description: Binary data