       SippCameraCreate [position] [point] [upvector] [focal]
              Create  a new camera. Positon is the point to world
              coordinates of the camera. Point is a world corrdi-
              nates point that he camera is to look at.  Upvector
              is a vector defining the up  direction.   The  only
              constraint  on  this  vector is that it must not be
              parallel to the viewing direction.

              Focal the focal ratio of the "camera". This is  the
              ratio  between  the  distance from the viewpoint to
              the screen and half the  screen  height.   A  large
              focal factor will result in a wide angle view while
              a small factor will give a telescopic effect.

                                              screen
                                              |
                                              | s
                  viewpoint                   |
                      *-----------------------|
                                  d           |
                                              |
                                              |

                      focal = s / d

              If any of the parameters is omitted or has a  empty
              value,  then that parameter is defaulted.  A camera
              handle is returned.  If a camera  is  not  created,
              the default camera, STDCAMERA, is used.
