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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.
+**
+** $Date: 2001/03/17 00:25:41 $ $Revision: 1.1 $
+** $Header: /home/krh/git/sync/mesa-cvs-repo/Mesa/src/glu/sgi/libtess/sweep.h,v 1.1 2001/03/17 00:25:41 brianp Exp $
+*/
+
+#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