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 * splitarcs.c++ 37 * 38 */ 39 40 //#include "glimports.h" 41 //#include "myassert.h" 42 //#include "mysetjmp.h" 43 //#include "mystdio.h" 44 #include "subdivider.h" 45 #include "arcsorter.h" 46 //#include "arc.h" 47 //#include "bin.h" 48 49 /* local preprocessor definitions */ 50 #define MAXARCS 10 51 52 /*---------------------------------------------------------------------------- 53 * Subdivider::split - split trim regions in source bin by line (param == value). 54 *---------------------------------------------------------------------------- 55 */ 56 57 void 58 Subdivider::split( Bin& bin, Bin& left, Bin& right, int param, REAL value ) 59 { 60 Bin intersections, unknown; 61 62 partition( bin, left, intersections, right, unknown, param, value ); 63 64 int count = intersections.numarcs(); 65 if( count % 2 ) { 66 #ifndef NDEBUG 67 left.show( "left" ); 68 intersections.show( "intersections" ); 69 right.show( "right" ); 70 #endif 71 ::mylongjmp( jumpbuffer, 29 ); 72 } 73 74 Arc_ptr arclist[MAXARCS], *list; 75 if( count >= MAXARCS ) { 76 list = new Arc_ptr[count]; 77 } else { 78 list = arclist; 79 } 80 81 Arc_ptr jarc, *last, *lptr; 82 for( last = list; (jarc=intersections.removearc()) != NULL; last++ ) 83 *last = jarc; 84 85 if( param == 0 ) { /* sort into increasing t order */ 86 ArcSdirSorter sorter(*this); 87 sorter.qsort( list, count ); 88 89 //::qsort ((void *)list, count, sizeof(Arc_ptr), (cmpfunc)compare_s); 90 for( lptr=list; lptr<last; lptr+=2 ) 91 check_s ( lptr[0], lptr[1] ); 92 for( lptr=list; lptr<last; lptr+=2 ) 93 join_s ( left, right, lptr[0], lptr[1] ); 94 for( lptr=list; lptr != last; lptr++ ) { 95 if( ((*lptr)->head()[0] <= value) && ((*lptr)->tail()[0] <= value) ) 96 left.addarc( *lptr ); 97 else 98 right.addarc( *lptr ); 99 } 100 } else { /* sort into decreasing s order */ 101 ArcTdirSorter sorter(*this); 102 sorter.qsort( list, count ); 103 //::qsort ((void *)list, count, sizeof(Arc_ptr), (cmpfunc)compare_t); 104 for( lptr=list; lptr<last; lptr+=2 ) 105 check_t ( lptr[0], lptr[1] ); 106 for( lptr=list; lptr<last; lptr+=2 ) 107 join_t ( left, right, lptr[0], lptr[1] ); 108 for( lptr=list; lptr != last; lptr++ ) { 109 if( ((*lptr)->head()[1] <= value) && ((*lptr)->tail()[1] <= value) ) 110 left.addarc( *lptr ); 111 else 112 right.addarc( *lptr ); 113 } 114 } 115 116 if( list != arclist ) delete[] list; 117 unknown.adopt(); 118 } 119 120 121 void 122 Subdivider::check_s( Arc_ptr jarc1, Arc_ptr jarc2 ) 123 { 124 assert( jarc1->check( ) != 0 ); 125 assert( jarc2->check( ) != 0 ); 126 assert( jarc1->next->check( ) != 0 ); 127 assert( jarc2->next->check( ) != 0 ); 128 assert( jarc1 != jarc2 ); 129 130 /* XXX - if these assertions fail, it is due to user error or 131 undersampling */ 132 if( ! ( jarc1->tail()[0] < (jarc1)->head()[0] ) ) { 133 #ifndef NDEBUG 134 _glu_dprintf( "s difference %f\n", (jarc1)->tail()[0] - (jarc1)->head()[0] ); 135 #endif 136 ::mylongjmp( jumpbuffer, 28 ); 137 } 138 139 if( ! ( jarc2->tail()[0] > (jarc2)->head()[0] ) ) { 140 #ifndef NDEBUG 141 _glu_dprintf( "s difference %f\n", (jarc2)->tail()[0] - (jarc2)->head()[0] ); 142 #endif 143 ::mylongjmp( jumpbuffer, 28 ); 144 } 145 } 146 147 inline void 148 Subdivider::link( Arc_ptr jarc1, Arc_ptr jarc2, Arc_ptr up, Arc_ptr down ) 149 { 150 up->nuid = down->nuid = 0; // XXX 151 152 up->next = jarc2; 153 down->next = jarc1; 154 up->prev = jarc1->prev; 155 down->prev = jarc2->prev; 156 157 down->next->prev = down; 158 up->next->prev = up; 159 down->prev->next = down; 160 up->prev->next = up; 161 } 162 163 inline void 164 Subdivider::simple_link( Arc_ptr jarc1, Arc_ptr jarc2 ) 165 { 166 Arc_ptr tmp = jarc2->prev; 167 jarc2->prev = jarc1->prev; 168 jarc1->prev = tmp; 169 jarc2->prev->next = jarc2; 170 jarc1->prev->next = jarc1; 171 } 172 173 174 /*---------------------------------------------------------------------------- 175 * join - add a pair of oppositely directed jordan arcs between two arcs 176 *---------------------------------------------------------------------------- 177 */ 178 179 void 180 Subdivider::join_s( Bin& left, Bin& right, Arc_ptr jarc1, Arc_ptr jarc2 ) 181 { 182 assert( jarc1->check( ) != 0); 183 assert( jarc2->check( ) != 0); 184 assert( jarc1 != jarc2 ); 185 186 if( ! jarc1->getitail() ) 187 jarc1 = jarc1->next; 188 189 if( ! jarc2->getitail() ) 190 jarc2 = jarc2->next; 191 192 REAL s = jarc1->tail()[0]; 193 REAL t1 = jarc1->tail()[1]; 194 REAL t2 = jarc2->tail()[1]; 195 196 if( t1 == t2 ) { 197 simple_link( jarc1, jarc2 ); 198 } else { 199 Arc_ptr newright = new(arcpool) Arc( arc_right, 0 ); 200 Arc_ptr newleft = new(arcpool) Arc( arc_left, 0 ); 201 assert( t1 < t2 ); 202 if( isBezierArcType() ) { 203 arctessellator.bezier( newright, s, s, t1, t2 ); 204 arctessellator.bezier( newleft, s, s, t2, t1 ); 205 } else { 206 arctessellator.pwl_right( newright, s, t1, t2, stepsizes[0] ); 207 arctessellator.pwl_left( newleft, s, t2, t1, stepsizes[2] ); 208 } 209 link( jarc1, jarc2, newright, newleft ); 210 left.addarc( newright ); 211 right.addarc( newleft ); 212 } 213 214 assert( jarc1->check( ) != 0 ); 215 assert( jarc2->check( ) != 0 ); 216 assert( jarc1->next->check( ) != 0); 217 assert( jarc2->next->check( ) != 0); 218 } 219 220 void 221 Subdivider::check_t( Arc_ptr jarc1, Arc_ptr jarc2 ) 222 { 223 assert( jarc1->check( ) != 0 ); 224 assert( jarc2->check( ) != 0 ); 225 assert( jarc1->next->check( ) != 0 ); 226 assert( jarc2->next->check( ) != 0 ); 227 assert( jarc1 != jarc2 ); 228 229 /* XXX - if these assertions fail, it is due to user error or 230 undersampling */ 231 if( ! ( jarc1->tail()[1] < (jarc1)->head()[1] ) ) { 232 #ifndef NDEBUG 233 _glu_dprintf( "t difference %f\n", jarc1->tail()[1] - (jarc1)->head()[1] ); 234 #endif 235 ::mylongjmp( jumpbuffer, 28 ); 236 } 237 238 if( ! ( jarc2->tail()[1] > (jarc2)->head()[1] ) ) { 239 #ifndef NDEBUG 240 _glu_dprintf( "t difference %f\n", jarc2->tail()[1] - (jarc2)->head()[1] ); 241 #endif 242 ::mylongjmp( jumpbuffer, 28 ); 243 } 244 } 245 246 /*---------------------------------------------------------------------------- 247 * join_t - add a pair of oppositely directed jordan arcs between two arcs 248 *---------------------------------------------------------------------------- 249 */ 250 251 void 252 Subdivider::join_t( Bin& bottom, Bin& top, Arc_ptr jarc1, Arc_ptr jarc2 ) 253 { 254 assert( jarc1->check( ) != 0 ); 255 assert( jarc2->check( ) != 0 ); 256 assert( jarc1->next->check( ) != 0 ); 257 assert( jarc2->next->check( ) != 0 ); 258 assert( jarc1 != jarc2 ); 259 260 if( ! jarc1->getitail() ) 261 jarc1 = jarc1->next; 262 263 if( ! jarc2->getitail() ) 264 jarc2 = jarc2->next; 265 266 REAL s1 = jarc1->tail()[0]; 267 REAL s2 = jarc2->tail()[0]; 268 REAL t = jarc1->tail()[1]; 269 270 if( s1 == s2 ) { 271 simple_link( jarc1, jarc2 ); 272 } else { 273 Arc_ptr newtop = new(arcpool) Arc( arc_top, 0 ); 274 Arc_ptr newbot = new(arcpool) Arc( arc_bottom, 0 ); 275 assert( s1 > s2 ); 276 if( isBezierArcType() ) { 277 arctessellator.bezier( newtop, s1, s2, t, t ); 278 arctessellator.bezier( newbot, s2, s1, t, t ); 279 } else { 280 arctessellator.pwl_top( newtop, t, s1, s2, stepsizes[1] ); 281 arctessellator.pwl_bottom( newbot, t, s2, s1, stepsizes[3] ); 282 } 283 link( jarc1, jarc2, newtop, newbot ); 284 bottom.addarc( newtop ); 285 top.addarc( newbot ); 286 } 287 288 assert( jarc1->check( ) != 0 ); 289 assert( jarc2->check( ) != 0 ); 290 assert( jarc1->next->check( ) != 0 ); 291 assert( jarc2->next->check( ) != 0 ); 292 } 293 294