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 1.0 (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/tess.h#6 $ 40 */ 41 42 #ifndef __tess_h_ 43 #define __tess_h_ 44 45 #include "glu.h" 46 #include <setjmp.h> 47 #include "mesh.h" 48 #include "dict.h" 49 #include "priorityq.h" 50 51 /* The begin/end calls must be properly nested. We keep track of 52 * the current state to enforce the ordering. 53 */ 54 enum TessState { T_DORMANT, T_IN_POLYGON, T_IN_CONTOUR }; 55 56 /* We cache vertex data for single-contour polygons so that we can 57 * try a quick-and-dirty decomposition first. 58 */ 59 #define TESS_MAX_CACHE 100 60 61 typedef struct CachedVertex { 62 GLdouble coords[3]; 63 void *data; 64 } CachedVertex; 65 66 struct GLUtesselator { 67 68 /*** state needed for collecting the input data ***/ 69 70 enum TessState state; /* what begin/end calls have we seen? */ 71 72 GLUhalfEdge *lastEdge; /* lastEdge->Org is the most recent vertex */ 73 GLUmesh *mesh; /* stores the input contours, and eventually 74 the tessellation itself */ 75 76 void (GLAPI *callError)( GLenum errnum ); 77 78 /*** state needed for projecting onto the sweep plane ***/ 79 80 GLdouble normal[3]; /* user-specified normal (if provided) */ 81 GLdouble sUnit[3]; /* unit vector in s-direction (debugging) */ 82 GLdouble tUnit[3]; /* unit vector in t-direction (debugging) */ 83 84 /*** state needed for the line sweep ***/ 85 86 GLdouble relTolerance; /* tolerance for merging features */ 87 GLenum windingRule; /* rule for determining polygon interior */ 88 GLboolean fatalError; /* fatal error: needed combine callback */ 89 90 Dict *dict; /* edge dictionary for sweep line */ 91 PriorityQ *pq; /* priority queue of vertex events */ 92 GLUvertex *event; /* current sweep event being processed */ 93 94 void (GLAPI *callCombine)( GLdouble coords[3], void *data[4], 95 GLfloat weight[4], void **outData ); 96 97 /*** state needed for rendering callbacks (see render.c) ***/ 98 99 GLboolean flagBoundary; /* mark boundary edges (use EdgeFlag) */ 100 GLboolean boundaryOnly; /* Extract contours, not triangles */ 101 GLUface *lonelyTriList; 102 /* list of triangles which could not be rendered as strips or fans */ 103 104 void (GLAPI *callBegin)( GLenum type ); 105 void (GLAPI *callEdgeFlag)( GLboolean boundaryEdge ); 106 void (GLAPI *callVertex)( void *data ); 107 void (GLAPI *callEnd)( void ); 108 void (GLAPI *callMesh)( GLUmesh *mesh ); 109 110 111 /*** state needed to cache single-contour polygons for renderCache() */ 112 113 GLboolean emptyCache; /* empty cache on next vertex() call */ 114 int cacheCount; /* number of cached vertices */ 115 CachedVertex cache[TESS_MAX_CACHE]; /* the vertex data */ 116 117 /*** rendering callbacks that also pass polygon data ***/ 118 void (GLAPI *callBeginData)( GLenum type, void *polygonData ); 119 void (GLAPI *callEdgeFlagData)( GLboolean boundaryEdge, 120 void *polygonData ); 121 void (GLAPI *callVertexData)( void *data, void *polygonData ); 122 void (GLAPI *callEndData)( void *polygonData ); 123 void (GLAPI *callErrorData)( GLenum errnum, void *polygonData ); 124 void (GLAPI *callCombineData)( GLdouble coords[3], void *data[4], 125 GLfloat weight[4], void **outData, 126 void *polygonData ); 127 128 jmp_buf env; /* place to jump to when memAllocs fail */ 129 130 void *polygonData; /* client data for current polygon */ 131 }; 132 133 void GLAPI __gl_noBeginData( GLenum type, void *polygonData ); 134 void GLAPI __gl_noEdgeFlagData( GLboolean boundaryEdge, void *polygonData ); 135 void GLAPI __gl_noVertexData( void *data, void *polygonData ); 136 void GLAPI __gl_noEndData( void *polygonData ); 137 void GLAPI __gl_noErrorData( GLenum errnum, void *polygonData ); 138 void GLAPI __gl_noCombineData( GLdouble coords[3], void *data[4], 139 GLfloat weight[4], void **outData, 140 void *polygonData ); 141 142 #define CALL_BEGIN_OR_BEGIN_DATA(a) \ 143 if (tess->callBeginData != &__gl_noBeginData) \ 144 (*tess->callBeginData)((a),tess->polygonData); \ 145 else (*tess->callBegin)((a)); 146 147 #define CALL_VERTEX_OR_VERTEX_DATA(a) \ 148 if (tess->callVertexData != &__gl_noVertexData) \ 149 (*tess->callVertexData)((a),tess->polygonData); \ 150 else (*tess->callVertex)((a)); 151 152 #define CALL_EDGE_FLAG_OR_EDGE_FLAG_DATA(a) \ 153 if (tess->callEdgeFlagData != &__gl_noEdgeFlagData) \ 154 (*tess->callEdgeFlagData)((a),tess->polygonData); \ 155 else (*tess->callEdgeFlag)((a)); 156 157 #define CALL_END_OR_END_DATA() \ 158 if (tess->callEndData != &__gl_noEndData) \ 159 (*tess->callEndData)(tess->polygonData); \ 160 else (*tess->callEnd)(); 161 162 #define CALL_COMBINE_OR_COMBINE_DATA(a,b,c,d) \ 163 if (tess->callCombineData != &__gl_noCombineData) \ 164 (*tess->callCombineData)((a),(b),(c),(d),tess->polygonData); \ 165 else (*tess->callCombine)((a),(b),(c),(d)); 166 167 #define CALL_ERROR_OR_ERROR_DATA(a) \ 168 if (tess->callErrorData != &__gl_noErrorData) \ 169 (*tess->callErrorData)((a),tess->polygonData); \ 170 else (*tess->callError)((a)); 171 172 #endif 173