gluBeginPolygon.3gl (GLU versions 1.0 and 1.1)

Name

  gluBeginPolygon, gluEndPolygon - delimit a polygon description

C Specification

  void gluBeginPolygon(	GLUtriangulatorObj *tobj )



  void gluEndPolygon( GLUtriangulatorObj *tobj )

Parameters

  tobj	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.

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, gluNextContour, gluTessCallback, gluTessVertex

Introduction | Alphabetic | Specification

Last Edited: Fri, May 26, 1995

AFV