1 /* 2 * SGI FREE SOFTWARE LICENSE B (Version 2.0, Sept. 18, 2008) 3 * Copyright (C) 1991-2000 Silicon Graphics, Inc. All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice including the dates of first publication and 13 * either this permission notice or a reference to 14 * http://oss.sgi.com/projects/FreeB/ 15 * shall be included in all copies or substantial portions of the Software. 16 * 17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 20 * SILICON GRAPHICS, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 21 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF 22 * OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 * SOFTWARE. 24 * 25 * Except as contained in this notice, the name of Silicon Graphics, Inc. 26 * shall not be used in advertising or otherwise to promote the sale, use or 27 * other dealings in this Software without prior written authorization from 28 * Silicon Graphics, Inc. 29 */ 30 /* 31 ** Author: Eric Veach, July 1994. 32 ** 33 */ 34 35 #ifndef __sweep_h_ 36 #define __sweep_h_ 37 38 //#include "mesh.h" 39 40 /* __gl_computeInterior( tess ) computes the planar arrangement specified 41 * by the given contours, and further subdivides this arrangement 42 * into regions. Each region is marked "inside" if it belongs 43 * to the polygon, according to the rule given by tess->windingRule. 44 * Each interior region is guaranteed be monotone. 45 */ 46 int __gl_computeInterior( GLUtesselator *tess ); 47 48 49 /* The following is here *only* for access by debugging routines */ 50 51 //#include "dict.h" 52 53 /* For each pair of adjacent edges crossing the sweep line, there is 54 * an ActiveRegion to represent the region between them. The active 55 * regions are kept in sorted order in a dynamic dictionary. As the 56 * sweep line crosses each vertex, we update the affected regions. 57 */ 58 59 struct ActiveRegion { 60 GLUhalfEdge *eUp; /* upper edge, directed right to left */ 61 DictNode *nodeUp; /* dictionary node corresponding to eUp */ 62 int windingNumber; /* used to determine which regions are 63 * inside the polygon */ 64 GLboolean inside; /* is this region inside the polygon? */ 65 GLboolean sentinel; /* marks fake edges at t = +/-infinity */ 66 GLboolean dirty; /* marks regions where the upper or lower 67 * edge has changed, but we haven't checked 68 * whether they intersect yet */ 69 GLboolean fixUpperEdge; /* marks temporary edges introduced when 70 * we process a "right vertex" (one without 71 * any edges leaving to the right) */ 72 }; 73 74 #define RegionBelow(r) ((ActiveRegion *) dictKey(dictPred((r)->nodeUp))) 75 #define RegionAbove(r) ((ActiveRegion *) dictKey(dictSucc((r)->nodeUp))) 76 77 #endif 78