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GLUNEXTCONTOUR()					      GLUNEXTCONTOUR()

NAME
       gluNextContour -	mark the beginning of another contour

C SPECIFICATION
       void gluNextContour( GLUtesselator* tess,
			    GLenum type	)

       delim $$

PARAMETERS
       tess  Specifies the tessellation	object (created	with gluNewTess).

       type  Specifies the type	of the contour being defined. Valid values are
	     GLU_EXTERIOR, GLU_INTERIOR, GLU_UNKNOWN, GLU_CCW, and GLU_CW.

DESCRIPTION
       gluNextContour is used in describing polygons with  multiple  contours.
       After  the  first  contour  has	been  described	 through  a  series of
       gluTessVertex calls, a gluNextContour call indicates that the  previous
       contour	is  complete and that the next contour is about	to begin.  An-
       other series of gluTessVertex calls is then used	to  describe  the  new
       contour.	 This process can be repeated until all	contours have been de-
       scribed.

       type defines what type of contour follows.  The legal contour types are
       as follows:

       GLU_EXTERIOR	 An  exterior  contour defines an exterior boundary of
			 the polygon.

       GLU_INTERIOR	 An interior contour defines an	interior  boundary  of
			 the polygon (such as a	hole).

       GLU_UNKNOWN	 An  unknown contour is	analyzed by the	library	to de-
			 termine if it is interior or exterior.

       GLU_CCW,

       GLU_CW		 The first GLU_CCW or GLU_CW contour defined  is  con-
			 sidered  to  be exterior. All other contours are con-
			 sidered to be exterior	if they	are  oriented  in  the
			 same direction	(clockwise or counterclockwise)	as the
			 first contour,	and interior if	they are not.

       If one contour is of type GLU_CCW or GLU_CW, then all contours must  be
       of the same type	(if they are not, then all GLU_CCW and GLU_CW contours
       will be changed to GLU_UNKNOWN).

       Note that there is no real difference between the  GLU_CCW  and	GLU_CW
       contour types.

       Before  the first contour is described, gluNextContour can be called to
       define the type of the first contour.  If gluNextContour	is not	called
       before  the  first  contour, then the first contour is marked GLU_EXTE-
       RIOR.

       This command is obsolete	and is	provided  for  backward	 compatibility
       only.  Calls to gluNextContour are mapped to gluTessEndContour followed
       by gluTessBeginContour.

EXAMPLE
       A quadrilateral with a triangular hole in it can	be described  as  fol-
       lows:

       gluBeginPolygon(tobj);
	  gluTessVertex(tobj, v1, v1);
	  gluTessVertex(tobj, v2, v2);
	  gluTessVertex(tobj, v3, v3);
	  gluTessVertex(tobj, v4, v4); gluNextContour(tobj, GLU_INTERIOR);
	  gluTessVertex(tobj, v5, v5);
	  gluTessVertex(tobj, v6, v6);
	  gluTessVertex(tobj, v7, v7); gluEndPolygon(tobj);

SEE ALSO
       gluBeginPolygon,	gluNewTess, gluTessCallback, gluTessVertex, gluTessBe-
       ginContour

							      GLUNEXTCONTOUR()

NAME | C SPECIFICATION | PARAMETERS | DESCRIPTION | EXAMPLE | SEE ALSO

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