1 /* 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: 9 ** 10 ** http://oss.sgi.com/projects/FreeB 11 ** 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. 17 ** 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. 23 ** 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. 33 ** 34 */ 35 /* 36 ** Author: Eric Veach, July 1994. 37 ** 38 ** $Date$ $Revision$ 39 ** $Header: //depot/main/gfx/lib/glu/libtess/tessmono.h#5 $ 40 */ 41 42 #ifndef __tessmono_h_ 43 #define __tessmono_h_ 44 45 /* __gl_meshTessellateMonoRegion( face ) tessellates a monotone region 46 * (what else would it do??) The region must consist of a single 47 * loop of half-edges (see mesh.h) oriented CCW. "Monotone" in this 48 * case means that any vertical line intersects the interior of the 49 * region in a single interval. 50 * 51 * Tessellation consists of adding interior edges (actually pairs of 52 * half-edges), to split the region into non-overlapping triangles. 53 * 54 * __gl_meshTessellateInterior( mesh ) tessellates each region of 55 * the mesh which is marked "inside" the polygon. Each such region 56 * must be monotone. 57 * 58 * __gl_meshDiscardExterior( mesh ) zaps (ie. sets to NULL) all faces 59 * which are not marked "inside" the polygon. Since further mesh operations 60 * on NULL faces are not allowed, the main purpose is to clean up the 61 * mesh so that exterior loops are not represented in the data structure. 62 * 63 * __gl_meshSetWindingNumber( mesh, value, keepOnlyBoundary ) resets the 64 * winding numbers on all edges so that regions marked "inside" the 65 * polygon have a winding number of "value", and regions outside 66 * have a winding number of 0. 67 * 68 * If keepOnlyBoundary is TRUE, it also deletes all edges which do not 69 * separate an interior region from an exterior one. 70 */ 71 72 int __gl_meshTessellateMonoRegion( GLUface *face ); 73 int __gl_meshTessellateInterior( GLUmesh *mesh ); 74 void __gl_meshDiscardExterior( GLUmesh *mesh ); 75 int __gl_meshSetWindingNumber( GLUmesh *mesh, int value, 76 GLboolean keepOnlyBoundary ); 77 78 #endif 79