2 ** License Applicability. Except to the extent portions of this file are
3 ** made subject to an alternative license as permitted in the SGI Free
4 ** Software License B, Version 1.1 (the "License"), the contents of this
5 ** file are subject only to the provisions of the License. You may not use
6 ** this file except in compliance with the License. You may obtain a copy
7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
10 ** http://oss.sgi.com/projects/FreeB
12 ** Note that, as provided in the License, the Software is distributed on an
13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
21 ** Copyright in any portions created by third parties is as indicated
22 ** elsewhere herein. All Rights Reserved.
24 ** Additional Notice Provisions: The application programming interfaces
25 ** established by SGI in conjunction with the Original Code are The
26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
31 ** published by SGI, but has not been independently verified as being
32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
36 ** Author: Eric Veach, July 1994.
38 ** $Date: 2001/03/17 00:25:41 $ $Revision: 1.1 $
39 ** $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 $
47 /* __gl_computeInterior( tess ) computes the planar arrangement specified
48 * by the given contours, and further subdivides this arrangement
49 * into regions. Each region is marked "inside" if it belongs
50 * to the polygon, according to the rule given by tess->windingRule.
51 * Each interior region is guaranteed be monotone.
53 int __gl_computeInterior( GLUtesselator
*tess
);
56 /* The following is here *only* for access by debugging routines */
60 /* For each pair of adjacent edges crossing the sweep line, there is
61 * an ActiveRegion to represent the region between them. The active
62 * regions are kept in sorted order in a dynamic dictionary. As the
63 * sweep line crosses each vertex, we update the affected regions.
67 GLUhalfEdge
*eUp
; /* upper edge, directed right to left */
68 DictNode
*nodeUp
; /* dictionary node corresponding to eUp */
69 int windingNumber
; /* used to determine which regions are
70 * inside the polygon */
71 GLboolean inside
; /* is this region inside the polygon? */
72 GLboolean sentinel
; /* marks fake edges at t = +/-infinity */
73 GLboolean dirty
; /* marks regions where the upper or lower
74 * edge has changed, but we haven't checked
75 * whether they intersect yet */
76 GLboolean fixUpperEdge
; /* marks temporary edges introduced when
77 * we process a "right vertex" (one without
78 * any edges leaving to the right) */
81 #define RegionBelow(r) ((ActiveRegion *) dictKey(dictPred((r)->nodeUp)))
82 #define RegionAbove(r) ((ActiveRegion *) dictKey(dictSucc((r)->nodeUp)))