PK_ERROR_code_t PK_FACE_delete_from_sheet_body
(
--- received arguments ---
PK_FACE_t       face          --- face
)


This function removes a face from sheet


Specific Errors:
    PK_ERROR_bad_wire       deleting face would result in an invalid wire body
    PK_ERROR_not_sheet      given body is not a sheet
    PK_ERROR_fragment       deleting face would disconnect the sheet



This routine deletes a face from a sheet body. The given face must be
a face of a sheet body, with or without a surface attached. Removal of
the face must not break the sheet into two or more parts.

If the body has more than one face, it remains a sheet body; edges and
vertices belonging to the face, but which are shared with no other
face, will be deleted along with it.

If the face is the only face of the sheet body, the result will be
either a wire or minimal body; none of the body's edges and vertices
will be deleted by the operation. The edges and vertices must form a
valid wire or minimal body, i.e. they must be connected (in a single
loop or a pair of bi-wire loops) and no vertex may be used by more
than two edges.