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** License Applicability. Except to the extent portions of this file are
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** made subject to an alternative license as permitted in the SGI Free
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** Software License B, Version 1.1 (the "License"), the contents of this
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** file are subject only to the provisions of the License. You may not use
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** this file except in compliance with the License. You may obtain a copy
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** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
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** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
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** http://oss.sgi.com/projects/FreeB
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** Note that, as provided in the License, the Software is distributed on an
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** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
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** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
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** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
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** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
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** Original Code. The Original Code is: OpenGL Sample Implementation,
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** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
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** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
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** Copyright in any portions created by third parties is as indicated
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** elsewhere herein. All Rights Reserved.
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** Additional Notice Provisions: The application programming interfaces
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** established by SGI in conjunction with the Original Code are The
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** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
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** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
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** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
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** Window System(R) (Version 1.3), released October 19, 1998. This software
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** was created using the OpenGL(R) version 1.2.1 Sample Implementation
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** published by SGI, but has not been independently verified as being
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** compliant with the OpenGL(R) version 1.2.1 Specification.
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** Author: Eric Veach, July 1994.
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** $Header: //depot/main/gfx/lib/glu/libtess/tessmono.h#5 $
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/* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region
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* (what else would it do??) The region must consist of a single
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* loop of half-edges (see mesh.h) oriented CCW. "Monotone" in this
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* case means that any vertical line intersects the interior of the
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* region in a single interval.
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* Tessellation consists of adding interior edges (actually pairs of
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* half-edges), to split the region into non-overlapping triangles.
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* __gl_meshTessellateInterior( mesh ) tessellates each region of
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* the mesh which is marked "inside" the polygon. Each such region
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* __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces
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* which are not marked "inside" the polygon. Since further mesh operations
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* on NULL faces are not allowed, the main purpose is to clean up the
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* mesh so that exterior loops are not represented in the data structure.
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* __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the
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* winding numbers on all edges so that regions marked "inside" the
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* polygon have a winding number of "value", and regions outside
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* have a winding number of 0.
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* If keepOnlyBoundary is TRUE, it also deletes all edges which do not
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* separate an interior region from an exterior one.
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int __gl_meshTessellateMonoRegion( GLUface *face );
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int __gl_meshTessellateInterior( GLUmesh *mesh );
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void __gl_meshDiscardExterior( GLUmesh *mesh );
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int __gl_meshSetWindingNumber( GLUmesh *mesh, int value,
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GLboolean keepOnlyBoundary );