glubeginpolygon(3g) [xfree86 man page]

GLUBEGINPOLYGON(3G)													       GLUBEGINPOLYGON(3G)

NAME

       gluBeginPolygon, gluEndPolygon - delimit a polygon description

C SPECIFICATION

       void gluBeginPolygon( GLUtesselator* tess )

       void gluEndPolygon( GLUtesselator* tess )

PARAMETERS

       tess  Specifies the tessellation object (created with gluNewTess).

DESCRIPTION

       gluBeginPolygon	and  gluEndPolygon  delimit  the definition of a nonconvex polygon.  To define such a polygon, first call gluBeginPolygon.
       Then define the contours of the polygon by calling gluTessVertex for each vertex and gluNextContour to start each  new  contour.   Finally,
       call gluEndPolygon to signal the end of the definition.	See the gluTessVertex and gluNextContour reference pages for more details.

       Once gluEndPolygon is called, the polygon is tessellated, and the resulting triangles are described through callbacks.  See gluTessCallback
       for descriptions of the callback functions.

NOTES

       This command is obsolete and is provided for backward compatibility only. Calls to gluBeginPolygon are mapped to  gluTessBeginPolygon  fol-
       lowed by gluTessBeginContour. Calls to gluEndPolygon are mapped to gluTessEndContour followed by gluTessEndPolygon.

EXAMPLE

       A quadrilateral with a triangular hole in it can be described like this:

       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

       gluNewTess(3G), gluNextContour(3G), gluTessCallback(3G), gluTessVertex(3G), gluTessBeginPolygon(3G), gluTessBeginContour(3G)

															       GLUBEGINPOLYGON(3G)

GLUTESSENDPOLYGON(3G)													     GLUTESSENDPOLYGON(3G)

NAME

       gluTessEndPolygon - delimit a polygon description

C SPECIFICATION

       void gluTessEndPolygon( GLUtesselator* tess )

PARAMETERS

       tess  Specifies the tessellation object (created with gluNewTess).

DESCRIPTION

       gluTessBeginPolygon  and  gluTessEndPolygon  delimit  the  definition  of  a  convex,  concave  or  self-intersecting  polygon. Within each
       gluTessBeginPolygon/gluTessEndPolygon pair, there must be one or more calls to gluTessBeginContour/gluTessEndContour.  Within each contour,
       there  are  zero  or  more  calls to gluTessVertex. The vertices specify a closed contour (the last vertex of each contour is automatically
       linked to the first). See the gluTessVertex, gluTessBeginContour and gluTessEndContour reference pages for more details.

       Once gluTessEndPolygon is called, the  polygon  is  tessellated,  and  the  resulting  triangles  are  described  through  callbacks.   See
       gluTessCallback for descriptions of the callback functions.

EXAMPLE

       A quadrilateral with a triangular hole in it can be described like this:

       gluTessBeginPolygon(tobj, NULL);
	gluTessBeginContour(tobj);
	  gluTessVertex(tobj, v1, v1);
	  gluTessVertex(tobj, v2, v2);
	  gluTessVertex(tobj, v3, v3);
	  gluTessVertex(tobj, v4, v4);
	gluTessEndContour(tobj);
	gluTessBeginContour(tobj);
	  gluTessVertex(tobj, v5, v5);
	  gluTessVertex(tobj, v6, v6);
	  gluTessVertex(tobj, v7, v7);
	gluTessEndContour(tobj); gluTessEndPolygon(tobj);
       In  the above example the pointers, v1 through v7, should point to different addresses, since the values stored at these addresses will not
       be read by the tesselator until gluTessEndPolygon is called.

SEE ALSO

       gluNewTess(3G),	  gluTessBeginContour(3G),     gluTessVertex(3G),     gluTessCallback(3G),     gluTessProperty(3G),	gluTessNormal(3G),
       gluTessBeginPolygon(3G)

															     GLUTESSENDPOLYGON(3G)