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GLUNEXTCONTOUR(3G)			  OpenGL Manual 		       GLUNEXTCONTOUR(3G)

NAME
       gluNextContour - mark the beginning of another contour

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

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. Another series of gluTessVertex() calls is then used to describe the new contour.
       This process can be repeated until all contours have been described.

       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 determine if it is interior or
	   exterior.

       GLU_CCW,

       GLU_CW
	   The first GLU_CCW or GLU_CW contour defined is considered to be exterior. All other
	   contours are considered 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_EXTERIOR.

       This command is obsolete and is provided for backward compatibility only.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 follows:

	   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(), gluTessBeginContour(), gluTessCallback(), gluTessVertex()

COPYRIGHT
       Copyright (C) 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI
       Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.

AUTHORS
       opengl.org

opengl.org				    06/10/2014			       GLUNEXTCONTOUR(3G)
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