1991-2006 Silicon Graphics, Inc.

gluBeginPolygon

3G

gluBeginPolygon

delimit a polygon description

# C Specification

                    void gluBeginPolygon
                    GLUtesselator* tess

## C Specification

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This command is obsolete and is provided for backward compatibility only.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

followed 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

,

gluNextContour

,

gluTessBeginContour

,

gluTessBeginPolygon

,

gluTessCallback

,

gluTessVertex

## Copyright

Copyright 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/.