void GLAPIENTRY gluEndTrim( GLUnurbs* nurb )

PARAMETERS
       nurb  Specifies the NURBS object (created with gluNewNurbsRenderer).

DESCRIPTION
       Use  gluBeginTrim  to  mark  the  beginning  of  a  trimming  loop,  and
       gluEndTrim to mark the end of a trimming loop. A trimming loop is a  set
       of  oriented  curve segments (forming a closed curve) that define bound‐
       aries of a NURBS surface. You include these trimming loops in the  defi‐
       nition  of  a  NURBS  surface,  between  calls  to  gluBeginSurface  and
       gluEndSurface.

       The definition for a NURBS surface can contain many trimming loops.  For
       example,  if you wrote a definition for a NURBS surface that resembled a
       rectangle with a hole punched out,  the  definition  would  contain  two
       trimming  loops.  One loop would define the outer edge of the rectangle;
       the other would define the hole punched out of the rectangle. The  defi‐
       nitions  of  each  of  these  trimming  loops  would  be  bracketed by a
       gluBeginTrim/gluEndTrim pair.

       The definition of a single closed trimming loop can consist of  multiple
       curve  segments,  each  described  as  a  piecewise  linear  curve  (see
       gluPwlCurve) or as a single NURBS curve (see  gluNurbsCurve),  or  as  a
       combination of both in any order. The only library calls that can appear
       in a trimming loop definition (between the  calls  to  gluBeginTrim  and
       gluEndTrim) are gluPwlCurve and gluNurbsCurve.

       The area of the NURBS surface that is displayed is the region in the do‐
       main to the left of the trimming curve as the curve parameter increases.
       Thus, the retained region of the NURBS surface is inside a counterclock‐
       wise trimming loop and outside a clockwise trimming loop. For  the  rec‐
       tangle  mentioned  earlier,  the trimming loop for the outer edge of the
       rectangle  runs  counterclockwise,  while  the  trimming  loop  for  the
       punched-out hole runs clockwise.

       If  you  use  more  than one curve to define a single trimming loop, the
       curve segments must form a closed loop (that is, the  endpoint  of  each
       curve  must be the starting point of the next curve, and the endpoint of
       the final curve must be the starting point of the first curve).  If  the
       endpoints  of  the curve are sufficiently close together but not exactly
       coincident, they will be coerced to match.  If  the  endpoints  are  not
       sufficiently close, an error results (see gluNurbsCallback).

       If a trimming loop definition contains multiple curves, the direction of
       the curves must be consistent (that is, the inside must be to  the  left
       of  all  of  the curves). Nested trimming loops are legal as long as the
       curve orientations alternate correctly.  If trimming curves are self-in‐
       tersecting, or intersect one another, an error results.

       If no trimming information is given for a NURBS surface, the entire sur‐

                                                               GLUBEGINTRIM(3G)