GitLab

Summary:
Create extrinsic parameters from eye point.
Create the rotation and translation from an eye point, look-at point and up vector.
see:
https://www.khronos.org/registry/OpenGL-Refpages/gl2.1/xhtml/gluLookAt.xml

It is arguably easier to initialise a camera position as a point in the world rather than an angle.
Pull Request resolved: https://github.com/facebookresearch/pytorch3d/pull/65

Reviewed By: bottler

Differential Revision: D20419652

Pulled By: nikhilaravi

fbshipit-source-id: 9caa1330860bb8bde1fb5c3864ed4cde836a5d19