1GLUTESSBEGINPOLYGON(3G)                                GLUTESSBEGINPOLYGON(3G)
2
3
4

NAME

6       gluTessBeginPolygon - delimit a polygon description
7
8

C SPECIFICATION

10       void gluTessBeginPolygon( GLUtesselator* tess,
11                                 GLvoid* data )
12
13

PARAMETERS

15       tess  Specifies the tessellation object (created with gluNewTess).
16
17       data  Specifies a pointer to user polygon data.
18

DESCRIPTION

20       gluTessBeginPolygon  and  gluTessEndPolygon delimit the definition of a
21       convex,   concave   or   self-intersecting   polygon.    Within    each
22       gluTessBeginPolygon/gluTessEndPolygon  pair,  there must be one or more
23       calls to gluTessBeginContour/gluTessEndContour.  Within  each  contour,
24       there  are  zero or more calls to gluTessVertex. The vertices specify a
25       closed contour (the last vertex of each contour is automatically linked
26       to   the   first).  See  the  gluTessVertex,  gluTessBeginContour,  and
27       gluTessEndContour reference pages for more details.
28
29       data is a pointer to a user-defined data structure. If the  appropriate
30       callback(s)  are  specified (see gluTessCallback), then this pointer is
31       returned to the callback function(s). Thus, it is a convenient  way  to
32       store per-polygon information.
33
34       Once  gluTessEndPolygon  is called, the polygon is tessellated, and the
35       resulting   triangles   are   described   through    callbacks.     See
36       gluTessCallback for descriptions of the callback functions.
37

EXAMPLE

39       A  quadrilateral  with a triangular hole in it can be described as fol‐
40       lows:
41
42       gluTessBeginPolygon(tobj, NULL);
43        gluTessBeginContour(tobj);
44          gluTessVertex(tobj, v1, v1);
45          gluTessVertex(tobj, v2, v2);
46          gluTessVertex(tobj, v3, v3);
47          gluTessVertex(tobj, v4, v4);
48        gluTessEndContour(tobj);
49        gluTessBeginContour(tobj);
50          gluTessVertex(tobj, v5, v5);
51          gluTessVertex(tobj, v6, v6);
52          gluTessVertex(tobj, v7, v7);
53        gluTessEndContour(tobj); gluTessEndPolygon(tobj);
54
55

SEE ALSO

57       gluNewTess(3G),       gluTessBeginContour(3G),       gluTessVertex(3G),
58       gluTessCallback(3G),       gluTessProperty(3G),      gluTessNormal(3G),
59       gluTessEndPolygon(3G)
60
61
62
63                                                       GLUTESSBEGINPOLYGON(3G)
Impressum