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GLUNEXTCONTOUR(3G)                                                                        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 pre-vious previous
       vious 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       This command is obsolete and is provided for backward compatibility only.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(3G), gluNewTess(3G), gluTessCallback(3G), gluTessVertex(3G), gluTessBeginContour(3G)





                                                                                          GLUNEXTCONTOUR(3G)