[eigen] Patch for quaternion normalization and cross product for Vector4f

[Rohit Garg <rpg.314@xxxxxxxxx>]

Hi,

Please find attached a ptch which implements quaternion normalization
and cross products for Vector4f. Now obviously, it isn't defined for
4d vectors, but this one crosses it assuming it as a 3 component
vector. The w component can be anything but will be set to zero after
the product. As the patch mentions, It is mainly meant for those ppl
who use vector4f instead of vector3f to use vectorization. I think
this can be helpful to those as earlier cross product has to be done
using vec3f.

Quaternion normalization is obviously useful. and it is now vectorized.

The patches are somewhat incomplete in the sense that I am not
familiar with the C++ and the intrinsics bridge so much. I am just
beginning to understand the guts of eigen and templates are even more
confusing for me. You may have to write (small hopefully) pieces of
glue code. On the intrinsics side, it should be complete, however. So,
please indulge me for a while. I promise to send more complete patches
in the future.

Here's how it was generated.

~/eigen2@rpg-lab> svn update
At revision 937616.
~/eigen2@rpg-lab> svn diff > rpg_patch
~/eigen2@rpg-lab> ls
bench  cmake  CMakeLists.txt  COPYING  COPYING.LESSER
CTestConfig.cmake  demos  disabled  doc  Doxyfile  Eigen  Mainpage.dox
 rpg_patch  test  unsupported
~/eigen2@rpg-lab>

I hope that is the correct way to generate patches. If it isn't please
tell me what is.

Regards,

-- 
Rohit Garg

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

Senior Undergraduate
Department of Physics
Indian Institute of Technology
Bombay

Attachment: rpg_patch
Description: Binary data