OURVSU ( surf, profil, point, direct, sense, nsings, parms, ifail )
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  Output surface of revolution

Receives:
  KI_tag_surface           *surf           --- spun surface to output

Returns:
  KI_tag_curve             *profil         --- curve revolved
  KI_vec_position           point          --- point on revolution axis
  KI_vec_axis               direct         --- direction of revolution axis
  KI_cod_logical           *sense          --- surface sense
 <KI_int_nitems>           *nsings         --- number of singularities
 <KI_tag_list_dbl>         *parms          --- parameter range on profile
  KI_cod_error             *ifail          --- error code

Specific errors:
  KI_unsuitable_entity      Entity is not a surface of revolution

Description:

  The details of a surface of revolution (type TYSUSU) are returned.

  The return argument 'nsings' is the number of singularities present on
  the surface and can be 0, 1, or 2. If 'nsings' is 1 or 2 then a list
  of two doubles is also returned which is the parameter range of the
  part of the profile curve which was used to create the surface.