1GLUBEGINPOLYGON(3G) OpenGL Manual GLUBEGINPOLYGON(3G)
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6 gluBeginPolygon - delimit a polygon description
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9 void gluBeginPolygon(GLUtesselator* tess);
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12 void gluEndPolygon(GLUtesselator* tess);
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15 tess
16 Specifies the tessellation object (created with gluNewTess()).
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19 gluBeginPolygon and gluEndPolygon() delimit the definition of a
20 nonconvex polygon. To define such a polygon, first call
21 gluBeginPolygon. Then define the contours of the polygon by calling
22 gluTessVertex() for each vertex and gluNextContour() to start each new
23 contour. Finally, call gluEndPolygon() to signal the end of the
24 definition. See the gluTessVertex() and gluNextContour() reference
25 pages for more details.
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27 Once gluEndPolygon() is called, the polygon is tessellated, and the
28 resulting triangles are described through callbacks. See
29 gluTessCallback() for descriptions of the callback functions.
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32 This command is obsolete and is provided for backward compatibility
33 only. Calls to gluBeginPolygon are mapped to gluTessBeginPolygon()
34 followed by gluTessBeginContour(). Calls to gluEndPolygon() are mapped
35 to gluTessEndContour() followed by gluTessEndPolygon().
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38 A quadrilateral with a triangular hole in it can be described like
39 this:
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41 gluBeginPolygon(tobj);
42 gluTessVertex(tobj, v1, v1);
43 gluTessVertex(tobj, v2, v2);
44 gluTessVertex(tobj, v3, v3);
45 gluTessVertex(tobj, v4, v4);
46 gluNextContour(tobj, GLU_INTERIOR);
47 gluTessVertex(tobj, v5, v5);
48 gluTessVertex(tobj, v6, v6);
49 gluTessVertex(tobj, v7, v7);
50 gluEndPolygon(tobj);
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55 gluNewTess(), gluNextContour(), gluTessBeginContour(),
56 gluTessBeginPolygon(), gluTessCallback(), gluTessVertex()
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59 Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed
60 under the SGI Free Software B License. For details, see
61 http://oss.sgi.com/projects/FreeB/.
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64 opengl.org
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68opengl.org 06/10/2014 GLUBEGINPOLYGON(3G)