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/*
** License Applicability. Except to the extent portions of this file are
** made subject to an alternative license as permitted in the SGI Free
** Software License B, Version 1.1 (the "License"), the contents of this
** file are subject only to the provisions of the License. You may not use
** this file except in compliance with the License. You may obtain a copy
** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
**
** http://oss.sgi.com/projects/FreeB
**
** Note that, as provided in the License, the Software is distributed on an
** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
**
** Original Code. The Original Code is: OpenGL Sample Implementation,
** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
** Copyright in any portions created by third parties is as indicated
** elsewhere herein. All Rights Reserved.
**
** Additional Notice Provisions: The application programming interfaces
** established by SGI in conjunction with the Original Code are The
** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
** Window System(R) (Version 1.3), released October 19, 1998. This software
** was created using the OpenGL(R) version 1.2.1 Sample Implementation
** published by SGI, but has not been independently verified as being
** compliant with the OpenGL(R) version 1.2.1 Specification.
**
*/
/*
** Author: Eric Veach, July 1994.
**
*/
#ifndef __sweep_h_
#define __sweep_h_
#include "mesh.h"
/* __gl_computeInterior( tess ) computes the planar arrangement specified
* by the given contours, and further subdivides this arrangement
* into regions. Each region is marked "inside" if it belongs
* to the polygon, according to the rule given by tess->windingRule.
* Each interior region is guaranteed be monotone.
*/
int __gl_computeInterior( GLUtesselator *tess );
/* The following is here *only* for access by debugging routines */
#include "dict.h"
/* For each pair of adjacent edges crossing the sweep line, there is
* an ActiveRegion to represent the region between them. The active
* regions are kept in sorted order in a dynamic dictionary. As the
* sweep line crosses each vertex, we update the affected regions.
*/
struct ActiveRegion {
GLUhalfEdge *eUp; /* upper edge, directed right to left */
DictNode *nodeUp; /* dictionary node corresponding to eUp */
int windingNumber; /* used to determine which regions are
* inside the polygon */
GLboolean inside; /* is this region inside the polygon? */
GLboolean sentinel; /* marks fake edges at t = +/-infinity */
GLboolean dirty; /* marks regions where the upper or lower
* edge has changed, but we haven't checked
* whether they intersect yet */
GLboolean fixUpperEdge; /* marks temporary edges introduced when
* we process a "right vertex" (one without
* any edges leaving to the right) */
};
#define RegionBelow(r) ((ActiveRegion *) dictKey(dictPred((r)->nodeUp)))
#define RegionAbove(r) ((ActiveRegion *) dictKey(dictSucc((r)->nodeUp)))
#endif
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