| 1 | /*<html><pre>  -<a                             href="qh-poly.htm" | 
| 2 | >-------------------------------</a><a name="TOP">-</a> | 
| 3 |  | 
| 4 | poly.c | 
| 5 | implements polygons and simplices | 
| 6 |  | 
| 7 | see qh-poly.htm, poly.h and qhull.h | 
| 8 |  | 
| 9 | infrequent code is in poly2.c | 
| 10 | (all but top 50 and their callers 12/3/95) | 
| 11 |  | 
| 12 | copyright (c) 1993-2003, The Geometry Center | 
| 13 | */ | 
| 14 |  | 
| 15 | #include "QuickHull/qhull_a.h" | 
| 16 |  | 
| 17 | /*======== functions in alphabetical order ==========*/ | 
| 18 |  | 
| 19 | /*-<a                             href="qh-poly.htm#TOC" | 
| 20 | >-------------------------------</a><a name="appendfacet">-</a> | 
| 21 |  | 
| 22 | qh_appendfacet( facet ) | 
| 23 | appends facet to end of qh.facet_list, | 
| 24 |  | 
| 25 | returns: | 
| 26 | updates qh.newfacet_list, facet_next, facet_list | 
| 27 | increments qh.numfacets | 
| 28 |  | 
| 29 | notes: | 
| 30 | assumes qh.facet_list/facet_tail is defined (createsimplex) | 
| 31 |  | 
| 32 | see: | 
| 33 | qh_removefacet() | 
| 34 |  | 
| 35 | */ | 
| 36 | void qh_appendfacet(facetT *facet) { | 
| 37 | facetT *tail= qh facet_tail; | 
| 38 |  | 
| 39 | if (tail == qh newfacet_list) | 
| 40 | qh newfacet_list= facet; | 
| 41 | if (tail == qh facet_next) | 
| 42 | qh facet_next= facet; | 
| 43 | facet->previous= tail->previous; | 
| 44 | facet->next= tail; | 
| 45 | if (tail->previous) | 
| 46 | tail->previous->next= facet; | 
| 47 | else | 
| 48 | qh facet_list= facet; | 
| 49 | tail->previous= facet; | 
| 50 | qh num_facets++; | 
| 51 | trace4((qh ferr, "qh_appendfacet: append f%d to facet_list\n", facet->id)); | 
| 52 | } /* appendfacet */ | 
| 53 |  | 
| 54 |  | 
| 55 | /*-<a                             href="qh-poly.htm#TOC" | 
| 56 | >-------------------------------</a><a name="appendvertex">-</a> | 
| 57 |  | 
| 58 | qh_appendvertex( vertex ) | 
| 59 | appends vertex to end of qh.vertex_list, | 
| 60 |  | 
| 61 | returns: | 
| 62 | sets vertex->newlist | 
| 63 | updates qh.vertex_list, newvertex_list | 
| 64 | increments qh.num_vertices | 
| 65 |  | 
| 66 | notes: | 
| 67 | assumes qh.vertex_list/vertex_tail is defined (createsimplex) | 
| 68 |  | 
| 69 | */ | 
| 70 | void qh_appendvertex (vertexT *vertex) { | 
| 71 | vertexT *tail= qh vertex_tail; | 
| 72 |  | 
| 73 | if (tail == qh newvertex_list) | 
| 74 | qh newvertex_list= vertex; | 
| 75 | vertex->newlist= True; | 
| 76 | vertex->previous= tail->previous; | 
| 77 | vertex->next= tail; | 
| 78 | if (tail->previous) | 
| 79 | tail->previous->next= vertex; | 
| 80 | else | 
| 81 | qh vertex_list= vertex; | 
| 82 | tail->previous= vertex; | 
| 83 | qh num_vertices++; | 
| 84 | trace4((qh ferr, "qh_appendvertex: append v%d to vertex_list\n", vertex->id)); | 
| 85 | } /* appendvertex */ | 
| 86 |  | 
| 87 |  | 
| 88 | /*-<a                             href="qh-poly.htm#TOC" | 
| 89 | >-------------------------------</a><a name="attachnewfacets">-</a> | 
| 90 |  | 
| 91 | qh_attachnewfacets( ) | 
| 92 | attach horizon facets to new facets in qh.newfacet_list | 
| 93 | newfacets have neighbor and ridge links to horizon but not vice versa | 
| 94 | only needed for qh.ONLYgood | 
| 95 |  | 
| 96 | returns: | 
| 97 | set qh.NEWfacets | 
| 98 | horizon facets linked to new facets | 
| 99 | ridges changed from visible facets to new facets | 
| 100 | simplicial ridges deleted | 
| 101 | qh.visible_list, no ridges valid | 
| 102 | facet->f.replace is a newfacet (if any) | 
| 103 |  | 
| 104 | design: | 
| 105 | delete interior ridges and neighbor sets by | 
| 106 | for each visible, non-simplicial facet | 
| 107 | for each ridge | 
| 108 | if last visit or if neighbor is simplicial | 
| 109 | if horizon neighbor | 
| 110 | delete ridge for horizon's ridge set | 
| 111 | delete ridge | 
| 112 | erase neighbor set | 
| 113 | attach horizon facets and new facets by | 
| 114 | for all new facets | 
| 115 | if corresponding horizon facet is simplicial | 
| 116 | locate corresponding visible facet {may be more than one} | 
| 117 | link visible facet to new facet | 
| 118 | replace visible facet with new facet in horizon | 
| 119 | else it's non-simplicial | 
| 120 | for all visible neighbors of the horizon facet | 
| 121 | link visible neighbor to new facet | 
| 122 | delete visible neighbor from horizon facet | 
| 123 | append new facet to horizon's neighbors | 
| 124 | the first ridge of the new facet is the horizon ridge | 
| 125 | link the new facet into the horizon ridge | 
| 126 | */ | 
| 127 | void qh_attachnewfacets (void ) { | 
| 128 | facetT *newfacet= NULL, *neighbor, **neighborp, *horizon, *visible; | 
| 129 | ridgeT *ridge, **ridgep; | 
| 130 |  | 
| 131 | qh NEWfacets= True; | 
| 132 | trace3((qh ferr, "qh_attachnewfacets: delete interior ridges\n")); | 
| 133 | qh visit_id++; | 
| 134 | FORALLvisible_facets { | 
| 135 | visible->visitid= qh visit_id; | 
| 136 | if (visible->ridges) { | 
| 137 | FOREACHridge_(visible->ridges) { | 
| 138 | neighbor= otherfacet_(ridge, visible); | 
| 139 | if (neighbor->visitid == qh visit_id | 
| 140 | || (!neighbor->visible && neighbor->simplicial)) { | 
| 141 | if (!neighbor->visible)  /* delete ridge for simplicial horizon */ | 
| 142 | qh_setdel (neighbor->ridges, ridge); | 
| 143 | qh_setfree (&(ridge->vertices)); /* delete on 2nd visit */ | 
| 144 | qh_memfree (ridge, sizeof(ridgeT)); | 
| 145 | } | 
| 146 | } | 
| 147 | SETfirst_(visible->ridges)= NULL; | 
| 148 | } | 
| 149 | SETfirst_(visible->neighbors)= NULL; | 
| 150 | } | 
| 151 | trace1((qh ferr, "qh_attachnewfacets: attach horizon facets to new facets\n")); | 
| 152 | FORALLnew_facets { | 
| 153 | horizon= SETfirstt_(newfacet->neighbors, facetT); | 
| 154 | if (horizon->simplicial) { | 
| 155 | visible= NULL; | 
| 156 | FOREACHneighbor_(horizon) {   /* may have more than one horizon ridge */ | 
| 157 | if (neighbor->visible) { | 
| 158 | if (visible) { | 
| 159 | if (qh_setequal_skip (newfacet->vertices, 0, horizon->vertices, | 
| 160 | SETindex_(horizon->neighbors, neighbor))) { | 
| 161 | visible= neighbor; | 
| 162 | break; | 
| 163 | } | 
| 164 | }else | 
| 165 | visible= neighbor; | 
| 166 | } | 
| 167 | } | 
| 168 | if (visible) { | 
| 169 | visible->f.replace= newfacet; | 
| 170 | qh_setreplace (horizon->neighbors, visible, newfacet); | 
| 171 | }else { | 
| 172 | fprintf (qh ferr, "qhull internal error (qh_attachnewfacets): couldn't find visible facet for horizon f%d of newfacet f%d\n", | 
| 173 | horizon->id, newfacet->id); | 
| 174 | qh_errexit2 (qh_ERRqhull, horizon, newfacet); | 
| 175 | } | 
| 176 | }else { /* non-simplicial, with a ridge for newfacet */ | 
| 177 | FOREACHneighbor_(horizon) {    /* may hold for many new facets */ | 
| 178 | if (neighbor->visible) { | 
| 179 | neighbor->f.replace= newfacet; | 
| 180 | qh_setdelnth (horizon->neighbors, | 
| 181 | SETindex_(horizon->neighbors, neighbor)); | 
| 182 | neighborp--; /* repeat */ | 
| 183 | } | 
| 184 | } | 
| 185 | qh_setappend (&horizon->neighbors, newfacet); | 
| 186 | ridge= SETfirstt_(newfacet->ridges, ridgeT); | 
| 187 | if (ridge->top == horizon) | 
| 188 | ridge->bottom= newfacet; | 
| 189 | else | 
| 190 | ridge->top= newfacet; | 
| 191 | } | 
| 192 | } /* newfacets */ | 
| 193 | if (qh PRINTstatistics) { | 
| 194 | FORALLvisible_facets { | 
| 195 | if (!visible->f.replace) | 
| 196 | zinc_(Zinsidevisible); | 
| 197 | } | 
| 198 | } | 
| 199 | } /* attachnewfacets */ | 
| 200 |  | 
| 201 | /*-<a                             href="qh-poly.htm#TOC" | 
| 202 | >-------------------------------</a><a name="checkflipped">-</a> | 
| 203 |  | 
| 204 | qh_checkflipped( facet, dist, allerror ) | 
| 205 | checks facet orientation to interior point | 
| 206 |  | 
| 207 | if allerror set, | 
| 208 | tests against qh.DISTround | 
| 209 | else | 
| 210 | tests against 0 since tested against DISTround before | 
| 211 |  | 
| 212 | returns: | 
| 213 | False if it flipped orientation (sets facet->flipped) | 
| 214 | distance if non-NULL | 
| 215 | */ | 
| 216 | boolT qh_checkflipped (facetT *facet, realT *distp, boolT allerror) { | 
| 217 | realT dist; | 
| 218 |  | 
| 219 | if (facet->flipped && !distp) | 
| 220 | return False; | 
| 221 | zzinc_(Zdistcheck); | 
| 222 | qh_distplane(qh interior_point, facet, &dist); | 
| 223 | if (distp) | 
| 224 | *distp= dist; | 
| 225 | if ((allerror && dist > -qh DISTround)|| (!allerror && dist >= 0.0)) { | 
| 226 | facet->flipped= True; | 
| 227 | zzinc_(Zflippedfacets); | 
| 228 | trace0((qh ferr, "qh_checkflipped: facet f%d is flipped, distance= %6.12g during p%d\n", facet->id, dist, qh furthest_id)); | 
| 229 | qh_precision ("flipped facet"); | 
| 230 | return False; | 
| 231 | } | 
| 232 | return True; | 
| 233 | } /* checkflipped */ | 
| 234 |  | 
| 235 | /*-<a                             href="qh-poly.htm#TOC" | 
| 236 | >-------------------------------</a><a name="delfacet">-</a> | 
| 237 |  | 
| 238 | qh_delfacet( facet ) | 
| 239 | removes facet from facet_list and frees up its memory | 
| 240 |  | 
| 241 | notes: | 
| 242 | assumes vertices and ridges already freed | 
| 243 | */ | 
| 244 | void qh_delfacet(facetT *facet) { | 
| 245 | void **freelistp; /* used !qh_NOmem */ | 
| 246 |  | 
| 247 | trace4((qh ferr, "qh_delfacet: delete f%d\n", facet->id)); | 
| 248 | if (facet == qh tracefacet) | 
| 249 | qh tracefacet= NULL; | 
| 250 | if (facet == qh GOODclosest) | 
| 251 | qh GOODclosest= NULL; | 
| 252 | qh_removefacet(facet); | 
| 253 | if (!facet->tricoplanar || facet->keepcentrum) { | 
| 254 | qh_memfree_(facet->normal, qh normal_size, freelistp); | 
| 255 | if (qh CENTERtype == qh_ASvoronoi) {   /* uses macro calls */ | 
| 256 | qh_memfree_(facet->center, qh center_size, freelistp); | 
| 257 | }else /* AScentrum */ { | 
| 258 | qh_memfree_(facet->center, qh normal_size, freelistp); | 
| 259 | } | 
| 260 | } | 
| 261 | qh_setfree(&(facet->neighbors)); | 
| 262 | if (facet->ridges) | 
| 263 | qh_setfree(&(facet->ridges)); | 
| 264 | qh_setfree(&(facet->vertices)); | 
| 265 | if (facet->outsideset) | 
| 266 | qh_setfree(&(facet->outsideset)); | 
| 267 | if (facet->coplanarset) | 
| 268 | qh_setfree(&(facet->coplanarset)); | 
| 269 | qh_memfree_(facet, sizeof(facetT), freelistp); | 
| 270 | } /* delfacet */ | 
| 271 |  | 
| 272 |  | 
| 273 | /*-<a                             href="qh-poly.htm#TOC" | 
| 274 | >-------------------------------</a><a name="deletevisible">-</a> | 
| 275 |  | 
| 276 | qh_deletevisible() | 
| 277 | delete visible facets and vertices | 
| 278 |  | 
| 279 | returns: | 
| 280 | deletes each facet and removes from facetlist | 
| 281 | at exit, qh.visible_list empty (== qh.newfacet_list) | 
| 282 |  | 
| 283 | notes: | 
| 284 | ridges already deleted | 
| 285 | horizon facets do not reference facets on qh.visible_list | 
| 286 | new facets in qh.newfacet_list | 
| 287 | uses   qh.visit_id; | 
| 288 | */ | 
| 289 | void qh_deletevisible (void /*qh visible_list*/) { | 
| 290 | facetT *visible, *nextfacet; | 
| 291 | vertexT *vertex, **vertexp; | 
| 292 | int numvisible= 0, numdel= qh_setsize(qh del_vertices); | 
| 293 |  | 
| 294 | trace1((qh ferr, "qh_deletevisible: delete %d visible facets and %d vertices\n", qh num_visible, numdel)); | 
| 295 | for (visible= qh visible_list; visible && visible->visible; | 
| 296 | visible= nextfacet) { /* deleting current */ | 
| 297 | nextfacet= visible->next; | 
| 298 | numvisible++; | 
| 299 | qh_delfacet(visible); | 
| 300 | } | 
| 301 | if (numvisible != qh num_visible) { | 
| 302 | fprintf (qh ferr, "qhull internal error (qh_deletevisible): qh num_visible %d is not number of visible facets %d\n", | 
| 303 | qh num_visible, numvisible); | 
| 304 | qh_errexit (qh_ERRqhull, NULL, NULL); | 
| 305 | } | 
| 306 | qh num_visible= 0; | 
| 307 | zadd_(Zvisfacettot, numvisible); | 
| 308 | zmax_(Zvisfacetmax, numvisible); | 
| 309 | zzadd_(Zdelvertextot, numdel); | 
| 310 | zmax_(Zdelvertexmax, numdel); | 
| 311 | FOREACHvertex_(qh del_vertices) | 
| 312 | qh_delvertex (vertex); | 
| 313 | qh_settruncate (qh del_vertices, 0); | 
| 314 | } /* deletevisible */ | 
| 315 |  | 
| 316 | /*-<a                             href="qh-poly.htm#TOC" | 
| 317 | >-------------------------------</a><a name="facetintersect">-</a> | 
| 318 |  | 
| 319 | qh_facetintersect( facetA, facetB, skipa, skipB, prepend ) | 
| 320 | return vertices for intersection of two simplicial facets | 
| 321 | may include 1 prepended entry (if more, need to settemppush) | 
| 322 |  | 
| 323 | returns: | 
| 324 | returns set of qh.hull_dim-1 + prepend vertices | 
| 325 | returns skipped index for each test and checks for exactly one | 
| 326 |  | 
| 327 | notes: | 
| 328 | does not need settemp since set in quick memory | 
| 329 |  | 
| 330 | see also: | 
| 331 | qh_vertexintersect and qh_vertexintersect_new | 
| 332 | please use qh_setnew_delnthsorted to get nth ridge (no skip information) | 
| 333 |  | 
| 334 | design: | 
| 335 | locate skipped vertex by scanning facet A's neighbors | 
| 336 | locate skipped vertex by scanning facet B's neighbors | 
| 337 | intersect the vertex sets | 
| 338 | */ | 
| 339 | setT *qh_facetintersect (facetT *facetA, facetT *facetB, | 
| 340 | int *skipA,int *skipB, int prepend) { | 
| 341 | setT *intersect; | 
| 342 | int dim= qh hull_dim, i, j; | 
| 343 | facetT **neighborsA, **neighborsB; | 
| 344 |  | 
| 345 | neighborsA= SETaddr_(facetA->neighbors, facetT); | 
| 346 | neighborsB= SETaddr_(facetB->neighbors, facetT); | 
| 347 | i= j= 0; | 
| 348 | if (facetB == *neighborsA++) | 
| 349 | *skipA= 0; | 
| 350 | else if (facetB == *neighborsA++) | 
| 351 | *skipA= 1; | 
| 352 | else if (facetB == *neighborsA++) | 
| 353 | *skipA= 2; | 
| 354 | else { | 
| 355 | for (i= 3; i < dim; i++) { | 
| 356 | if (facetB == *neighborsA++) { | 
| 357 | *skipA= i; | 
| 358 | break; | 
| 359 | } | 
| 360 | } | 
| 361 | } | 
| 362 | if (facetA == *neighborsB++) | 
| 363 | *skipB= 0; | 
| 364 | else if (facetA == *neighborsB++) | 
| 365 | *skipB= 1; | 
| 366 | else if (facetA == *neighborsB++) | 
| 367 | *skipB= 2; | 
| 368 | else { | 
| 369 | for (j= 3; j < dim; j++) { | 
| 370 | if (facetA == *neighborsB++) { | 
| 371 | *skipB= j; | 
| 372 | break; | 
| 373 | } | 
| 374 | } | 
| 375 | } | 
| 376 | if (i >= dim || j >= dim) { | 
| 377 | fprintf (qh ferr, "qhull internal error (qh_facetintersect): f%d or f%d not in others neighbors\n", | 
| 378 | facetA->id, facetB->id); | 
| 379 | qh_errexit2 (qh_ERRqhull, facetA, facetB); | 
| 380 | } | 
| 381 | intersect= qh_setnew_delnthsorted (facetA->vertices, qh hull_dim, *skipA, prepend); | 
| 382 | trace4((qh ferr, "qh_facetintersect: f%d skip %d matches f%d skip %d\n", facetA->id, *skipA, facetB->id, *skipB)); | 
| 383 | return(intersect); | 
| 384 | } /* facetintersect */ | 
| 385 |  | 
| 386 | /*-<a                             href="qh-poly.htm#TOC" | 
| 387 | >-------------------------------</a><a name="gethash">-</a> | 
| 388 |  | 
| 389 | qh_gethash( hashsize, set, size, firstindex, skipelem ) | 
| 390 | return hashvalue for a set with firstindex and skipelem | 
| 391 |  | 
| 392 | notes: | 
| 393 | assumes at least firstindex+1 elements | 
| 394 | assumes skipelem is NULL, in set, or part of hash | 
| 395 |  | 
| 396 | hashes memory addresses which may change over different runs of the same data | 
| 397 | using sum for hash does badly in high d | 
| 398 | */ | 
| 399 | unsigned qh_gethash (int hashsize, setT *set, int size, int firstindex, void *skipelem) { | 
| 400 | void **elemp= SETelemaddr_(set, firstindex, void); | 
| 401 | ptr_intT hash = 0, elem; | 
| 402 | int i; | 
| 403 |  | 
| 404 | switch (size-firstindex) { | 
| 405 | case 1: | 
| 406 | hash= (ptr_intT)(*elemp) - (ptr_intT) skipelem; | 
| 407 | break; | 
| 408 | case 2: | 
| 409 | hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] - (ptr_intT) skipelem; | 
| 410 | break; | 
| 411 | case 3: | 
| 412 | hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] | 
| 413 | - (ptr_intT) skipelem; | 
| 414 | break; | 
| 415 | case 4: | 
| 416 | hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] | 
| 417 | + (ptr_intT)elemp[3] - (ptr_intT) skipelem; | 
| 418 | break; | 
| 419 | case 5: | 
| 420 | hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] | 
| 421 | + (ptr_intT)elemp[3] + (ptr_intT)elemp[4] - (ptr_intT) skipelem; | 
| 422 | break; | 
| 423 | case 6: | 
| 424 | hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] | 
| 425 | + (ptr_intT)elemp[3] + (ptr_intT)elemp[4]+ (ptr_intT)elemp[5] | 
| 426 | - (ptr_intT) skipelem; | 
| 427 | break; | 
| 428 | default: | 
| 429 | hash= 0; | 
| 430 | i= 3; | 
| 431 | do {     /* this is about 10% in 10-d */ | 
| 432 | if ((elem= (ptr_intT)*elemp++) != (ptr_intT)skipelem) { | 
| 433 | hash ^= (elem << i) + (elem >> (32-i)); | 
| 434 | i += 3; | 
| 435 | if (i >= 32) | 
| 436 | i -= 32; | 
| 437 | } | 
| 438 | }while(*elemp); | 
| 439 | break; | 
| 440 | } | 
| 441 | hash %= (ptr_intT) hashsize; | 
| 442 | /* hash= 0; for debugging purposes */ | 
| 443 | return hash; | 
| 444 | } /* gethash */ | 
| 445 |  | 
| 446 | /*-<a                             href="qh-poly.htm#TOC" | 
| 447 | >-------------------------------</a><a name="makenewfacet">-</a> | 
| 448 |  | 
| 449 | qh_makenewfacet( vertices, toporient, horizon ) | 
| 450 | creates a toporient? facet from vertices | 
| 451 |  | 
| 452 | returns: | 
| 453 | returns newfacet | 
| 454 | adds newfacet to qh.facet_list | 
| 455 | newfacet->vertices= vertices | 
| 456 | if horizon | 
| 457 | newfacet->neighbor= horizon, but not vice versa | 
| 458 | newvertex_list updated with vertices | 
| 459 | */ | 
| 460 | facetT *qh_makenewfacet(setT *vertices, boolT toporient,facetT *horizon) { | 
| 461 | facetT *newfacet; | 
| 462 | vertexT *vertex, **vertexp; | 
| 463 |  | 
| 464 | FOREACHvertex_(vertices) { | 
| 465 | if (!vertex->newlist) { | 
| 466 | qh_removevertex (vertex); | 
| 467 | qh_appendvertex (vertex); | 
| 468 | } | 
| 469 | } | 
| 470 | newfacet= qh_newfacet(); | 
| 471 | newfacet->vertices= vertices; | 
| 472 | newfacet->toporient= toporient; | 
| 473 | if (horizon) | 
| 474 | qh_setappend(&(newfacet->neighbors), horizon); | 
| 475 | qh_appendfacet(newfacet); | 
| 476 | return(newfacet); | 
| 477 | } /* makenewfacet */ | 
| 478 |  | 
| 479 |  | 
| 480 | /*-<a                             href="qh-poly.htm#TOC" | 
| 481 | >-------------------------------</a><a name="makenewplanes">-</a> | 
| 482 |  | 
| 483 | qh_makenewplanes() | 
| 484 | make new hyperplanes for facets on qh.newfacet_list | 
| 485 |  | 
| 486 | returns: | 
| 487 | all facets have hyperplanes or are marked for   merging | 
| 488 | doesn't create hyperplane if horizon is coplanar (will merge) | 
| 489 | updates qh.min_vertex if qh.JOGGLEmax | 
| 490 |  | 
| 491 | notes: | 
| 492 | facet->f.samecycle is defined for facet->mergehorizon facets | 
| 493 | */ | 
| 494 | void qh_makenewplanes (void /* newfacet_list */) { | 
| 495 | facetT *newfacet; | 
| 496 |  | 
| 497 | FORALLnew_facets { | 
| 498 | if (!newfacet->mergehorizon) | 
| 499 | qh_setfacetplane (newfacet); | 
| 500 | } | 
| 501 | if (qh JOGGLEmax < REALmax/2) | 
| 502 | minimize_(qh min_vertex, -wwval_(Wnewvertexmax)); | 
| 503 | } /* makenewplanes */ | 
| 504 |  | 
| 505 | /*-<a                             href="qh-poly.htm#TOC" | 
| 506 | >-------------------------------</a><a name="makenew_nonsimplicial">-</a> | 
| 507 |  | 
| 508 | qh_makenew_nonsimplicial( visible, apex, numnew ) | 
| 509 | make new facets for ridges of a visible facet | 
| 510 |  | 
| 511 | returns: | 
| 512 | first newfacet, bumps numnew as needed | 
| 513 | attaches new facets if !qh.ONLYgood | 
| 514 | marks ridge neighbors for simplicial visible | 
| 515 | if (qh.ONLYgood) | 
| 516 | ridges on newfacet, horizon, and visible | 
| 517 | else | 
| 518 | ridge and neighbors between newfacet and   horizon | 
| 519 | visible facet's ridges are deleted | 
| 520 |  | 
| 521 | notes: | 
| 522 | qh.visit_id if visible has already been processed | 
| 523 | sets neighbor->seen for building f.samecycle | 
| 524 | assumes all 'seen' flags initially false | 
| 525 |  | 
| 526 | design: | 
| 527 | for each ridge of visible facet | 
| 528 | get neighbor of visible facet | 
| 529 | if neighbor was already processed | 
| 530 | delete the ridge (will delete all visible facets later) | 
| 531 | if neighbor is a horizon facet | 
| 532 | create a new facet | 
| 533 | if neighbor coplanar | 
| 534 | adds newfacet to f.samecycle for later merging | 
| 535 | else | 
| 536 | updates neighbor's neighbor set | 
| 537 | (checks for non-simplicial facet with multiple ridges to visible facet) | 
| 538 | updates neighbor's ridge set | 
| 539 | (checks for simplicial neighbor to non-simplicial visible facet) | 
| 540 | (deletes ridge if neighbor is simplicial) | 
| 541 |  | 
| 542 | */ | 
| 543 | #ifndef qh_NOmerge | 
| 544 | facetT *qh_makenew_nonsimplicial (facetT *visible, vertexT *apex, int *numnew) { | 
| 545 | void **freelistp; /* used !qh_NOmem */ | 
| 546 | ridgeT *ridge, **ridgep; | 
| 547 | facetT *neighbor, *newfacet= NULL, *samecycle; | 
| 548 | setT *vertices; | 
| 549 | boolT toporient; | 
| 550 | int ridgeid; | 
| 551 |  | 
| 552 | FOREACHridge_(visible->ridges) { | 
| 553 | ridgeid= ridge->id; | 
| 554 | neighbor= otherfacet_(ridge, visible); | 
| 555 | if (neighbor->visible) { | 
| 556 | if (!qh ONLYgood) { | 
| 557 | if (neighbor->visitid == qh visit_id) { | 
| 558 | qh_setfree (&(ridge->vertices));  /* delete on 2nd visit */ | 
| 559 | qh_memfree_(ridge, sizeof(ridgeT), freelistp); | 
| 560 | } | 
| 561 | } | 
| 562 | }else {  /* neighbor is an horizon facet */ | 
| 563 | toporient= (ridge->top == visible); | 
| 564 | vertices= qh_setnew (qh hull_dim); /* makes sure this is quick */ | 
| 565 | qh_setappend (&vertices, apex); | 
| 566 | qh_setappend_set (&vertices, ridge->vertices); | 
| 567 | newfacet= qh_makenewfacet(vertices, toporient, neighbor); | 
| 568 | (*numnew)++; | 
| 569 | if (neighbor->coplanar) { | 
| 570 | newfacet->mergehorizon= True; | 
| 571 | if (!neighbor->seen) { | 
| 572 | newfacet->f.samecycle= newfacet; | 
| 573 | neighbor->f.newcycle= newfacet; | 
| 574 | }else { | 
| 575 | samecycle= neighbor->f.newcycle; | 
| 576 | newfacet->f.samecycle= samecycle->f.samecycle; | 
| 577 | samecycle->f.samecycle= newfacet; | 
| 578 | } | 
| 579 | } | 
| 580 | if (qh ONLYgood) { | 
| 581 | if (!neighbor->simplicial) | 
| 582 | qh_setappend(&(newfacet->ridges), ridge); | 
| 583 | }else {  /* qh_attachnewfacets */ | 
| 584 | if (neighbor->seen) { | 
| 585 | if (neighbor->simplicial) { | 
| 586 | fprintf (qh ferr, "qhull internal error (qh_makenew_nonsimplicial): simplicial f%d sharing two ridges with f%d\n", | 
| 587 | neighbor->id, visible->id); | 
| 588 | qh_errexit2 (qh_ERRqhull, neighbor, visible); | 
| 589 | } | 
| 590 | qh_setappend (&(neighbor->neighbors), newfacet); | 
| 591 | }else | 
| 592 | qh_setreplace (neighbor->neighbors, visible, newfacet); | 
| 593 | if (neighbor->simplicial) { | 
| 594 | qh_setdel (neighbor->ridges, ridge); | 
| 595 | qh_setfree (&(ridge->vertices)); | 
| 596 | qh_memfree (ridge, sizeof(ridgeT)); | 
| 597 | }else { | 
| 598 | qh_setappend(&(newfacet->ridges), ridge); | 
| 599 | if (toporient) | 
| 600 | ridge->top= newfacet; | 
| 601 | else | 
| 602 | ridge->bottom= newfacet; | 
| 603 | } | 
| 604 | trace4((qh ferr, "qh_makenew_nonsimplicial: created facet f%d from v%d and r%d of horizon f%d\n", newfacet->id, apex->id, ridgeid, neighbor->id)); | 
| 605 | } | 
| 606 | } | 
| 607 | neighbor->seen= True; | 
| 608 | } /* for each ridge */ | 
| 609 | if (!qh ONLYgood) | 
| 610 | SETfirst_(visible->ridges)= NULL; | 
| 611 | return newfacet; | 
| 612 | } /* makenew_nonsimplicial */ | 
| 613 | #else /* qh_NOmerge */ | 
| 614 | facetT *qh_makenew_nonsimplicial (facetT *visible, vertexT *apex, int *numnew) { | 
| 615 | return NULL; | 
| 616 | } | 
| 617 | #endif /* qh_NOmerge */ | 
| 618 |  | 
| 619 | /*-<a                             href="qh-poly.htm#TOC" | 
| 620 | >-------------------------------</a><a name="makenew_simplicial">-</a> | 
| 621 |  | 
| 622 | qh_makenew_simplicial( visible, apex, numnew ) | 
| 623 | make new facets for simplicial visible facet and apex | 
| 624 |  | 
| 625 | returns: | 
| 626 | attaches new facets if (!qh.ONLYgood) | 
| 627 | neighbors between newfacet and horizon | 
| 628 |  | 
| 629 | notes: | 
| 630 | nop if neighbor->seen or neighbor->visible (see qh_makenew_nonsimplicial) | 
| 631 |  | 
| 632 | design: | 
| 633 | locate neighboring horizon facet for visible facet | 
| 634 | determine vertices and orientation | 
| 635 | create new facet | 
| 636 | if coplanar, | 
| 637 | add new facet to f.samecycle | 
| 638 | update horizon facet's neighbor list | 
| 639 | */ | 
| 640 | facetT *qh_makenew_simplicial (facetT *visible, vertexT *apex, int *numnew) { | 
| 641 | facetT *neighbor, **neighborp, *newfacet= NULL; | 
| 642 | setT *vertices; | 
| 643 | boolT flip, toporient; | 
| 644 | int horizonskip, visibleskip; | 
| 645 |  | 
| 646 | FOREACHneighbor_(visible) { | 
| 647 | if (!neighbor->seen && !neighbor->visible) { | 
| 648 | vertices= qh_facetintersect(neighbor,visible, &horizonskip, &visibleskip, 1); | 
| 649 | SETfirst_(vertices)= apex; | 
| 650 | flip= ((horizonskip & 0x1) ^ (visibleskip & 0x1)); | 
| 651 | if (neighbor->toporient) | 
| 652 | toporient= horizonskip & 0x1; | 
| 653 | else | 
| 654 | toporient= (horizonskip & 0x1) ^ 0x1; | 
| 655 | newfacet= qh_makenewfacet(vertices, toporient, neighbor); | 
| 656 | (*numnew)++; | 
| 657 | if (neighbor->coplanar && (qh PREmerge || qh MERGEexact)) { | 
| 658 | #ifndef qh_NOmerge | 
| 659 | newfacet->f.samecycle= newfacet; | 
| 660 | newfacet->mergehorizon= True; | 
| 661 | #endif | 
| 662 | } | 
| 663 | if (!qh ONLYgood) | 
| 664 | SETelem_(neighbor->neighbors, horizonskip)= newfacet; | 
| 665 | trace4((qh ferr, "qh_makenew_simplicial: create facet f%d top %d from v%d and horizon f%d skip %d top %d and visible f%d skip %d, flip? %d\n", newfacet->id, toporient, apex->id, neighbor->id, horizonskip, neighbor->toporient, visible->id, visibleskip, flip)); | 
| 666 | } | 
| 667 | } | 
| 668 | return newfacet; | 
| 669 | } /* makenew_simplicial */ | 
| 670 |  | 
| 671 | /*-<a                             href="qh-poly.htm#TOC" | 
| 672 | >-------------------------------</a><a name="matchneighbor">-</a> | 
| 673 |  | 
| 674 | qh_matchneighbor( newfacet, newskip, hashsize, hashcount ) | 
| 675 | either match subridge of newfacet with neighbor or add to hash_table | 
| 676 |  | 
| 677 | returns: | 
| 678 | duplicate ridges are unmatched and marked by qh_DUPLICATEridge | 
| 679 |  | 
| 680 | notes: | 
| 681 | ridge is newfacet->vertices w/o newskip vertex | 
| 682 | do not allocate memory (need to free hash_table cleanly) | 
| 683 | uses linear hash chains | 
| 684 |  | 
| 685 | see also: | 
| 686 | qh_matchduplicates | 
| 687 |  | 
| 688 | design: | 
| 689 | for each possible matching facet in qh.hash_table | 
| 690 | if vertices match | 
| 691 | set ismatch, if facets have opposite orientation | 
| 692 | if ismatch and matching facet doesn't have a match | 
| 693 | match the facets by updating their neighbor sets | 
| 694 | else | 
| 695 | indicate a duplicate ridge | 
| 696 | set facet hyperplane for later testing | 
| 697 | add facet to hashtable | 
| 698 | unless the other facet was already a duplicate ridge | 
| 699 | mark both facets with a duplicate ridge | 
| 700 | add other facet (if defined) to hash table | 
| 701 | */ | 
| 702 | void qh_matchneighbor (facetT *newfacet, int newskip, int hashsize, int *hashcount) { | 
| 703 | boolT newfound= False;   /* True, if new facet is already in hash chain */ | 
| 704 | boolT same, ismatch; | 
| 705 | int hash, scan; | 
| 706 | facetT *facet, *matchfacet; | 
| 707 | int skip, matchskip; | 
| 708 |  | 
| 709 | hash= (int)qh_gethash (hashsize, newfacet->vertices, qh hull_dim, 1, | 
| 710 | SETelem_(newfacet->vertices, newskip)); | 
| 711 | trace4((qh ferr, "qh_matchneighbor: newfacet f%d skip %d hash %d hashcount %d\n", newfacet->id, newskip, hash, *hashcount)); | 
| 712 | zinc_(Zhashlookup); | 
| 713 | for (scan= hash; (facet= SETelemt_(qh hash_table, scan, facetT)); | 
| 714 | scan= (++scan >= hashsize ? 0 : scan)) { | 
| 715 | if (facet == newfacet) { | 
| 716 | newfound= True; | 
| 717 | continue; | 
| 718 | } | 
| 719 | zinc_(Zhashtests); | 
| 720 | if (qh_matchvertices (1, newfacet->vertices, newskip, facet->vertices, &skip, &same)) { | 
| 721 | if (SETelem_(newfacet->vertices, newskip) == | 
| 722 | SETelem_(facet->vertices, skip)) { | 
| 723 | qh_precision ("two facets with the same vertices"); | 
| 724 | fprintf (qh ferr, "qhull precision error: Vertex sets are the same for f%d and f%d.  Can not force output.\n", | 
| 725 | facet->id, newfacet->id); | 
| 726 | qh_errexit2 (qh_ERRprec, facet, newfacet); | 
| 727 | } | 
| 728 | ismatch= (same == (newfacet->toporient ^ facet->toporient)); | 
| 729 | matchfacet= SETelemt_(facet->neighbors, skip, facetT); | 
| 730 | if (ismatch && !matchfacet) { | 
| 731 | SETelem_(facet->neighbors, skip)= newfacet; | 
| 732 | SETelem_(newfacet->neighbors, newskip)= facet; | 
| 733 | (*hashcount)--; | 
| 734 | trace4((qh ferr, "qh_matchneighbor: f%d skip %d matched with new f%d skip %d\n", facet->id, skip, newfacet->id, newskip)); | 
| 735 | return; | 
| 736 | } | 
| 737 | if (!qh PREmerge && !qh MERGEexact) { | 
| 738 | qh_precision ("a ridge with more than two neighbors"); | 
| 739 | fprintf (qh ferr, "qhull precision error: facets f%d, f%d and f%d meet at a ridge with more than 2 neighbors.  Can not continue.\n", | 
| 740 | facet->id, newfacet->id, getid_(matchfacet)); | 
| 741 | qh_errexit2 (qh_ERRprec, facet, newfacet); | 
| 742 | } | 
| 743 | SETelem_(newfacet->neighbors, newskip)= qh_DUPLICATEridge; | 
| 744 | newfacet->dupridge= True; | 
| 745 | if (!newfacet->normal) | 
| 746 | qh_setfacetplane (newfacet); | 
| 747 | qh_addhash (newfacet, qh hash_table, hashsize, hash); | 
| 748 | (*hashcount)++; | 
| 749 | if (!facet->normal) | 
| 750 | qh_setfacetplane (facet); | 
| 751 | if (matchfacet != qh_DUPLICATEridge) { | 
| 752 | SETelem_(facet->neighbors, skip)= qh_DUPLICATEridge; | 
| 753 | facet->dupridge= True; | 
| 754 | if (!facet->normal) | 
| 755 | qh_setfacetplane (facet); | 
| 756 | if (matchfacet) { | 
| 757 | matchskip= qh_setindex (matchfacet->neighbors, facet); | 
| 758 | SETelem_(matchfacet->neighbors, matchskip)= qh_DUPLICATEridge; | 
| 759 | matchfacet->dupridge= True; | 
| 760 | if (!matchfacet->normal) | 
| 761 | qh_setfacetplane (matchfacet); | 
| 762 | qh_addhash (matchfacet, qh hash_table, hashsize, hash); | 
| 763 | *hashcount += 2; | 
| 764 | } | 
| 765 | } | 
| 766 | trace4((qh ferr, "qh_matchneighbor: new f%d skip %d duplicates ridge for f%d skip %d matching f%d ismatch %d at hash %d\n", newfacet->id, newskip, facet->id, skip, (matchfacet == qh_DUPLICATEridge ? -2 : getid_(matchfacet)), ismatch, hash)); | 
| 767 | return; /* end of duplicate ridge */ | 
| 768 | } | 
| 769 | } | 
| 770 | if (!newfound) | 
| 771 | SETelem_(qh hash_table, scan)= newfacet;  /* same as qh_addhash */ | 
| 772 | (*hashcount)++; | 
| 773 | trace4((qh ferr, "qh_matchneighbor: no match for f%d skip %d at hash %d\n", newfacet->id, newskip, hash)); | 
| 774 | } /* matchneighbor */ | 
| 775 |  | 
| 776 |  | 
| 777 | /*-<a                             href="qh-poly.htm#TOC" | 
| 778 | >-------------------------------</a><a name="matchnewfacets">-</a> | 
| 779 |  | 
| 780 | qh_matchnewfacets() | 
| 781 | match newfacets in qh.newfacet_list to their newfacet neighbors | 
| 782 |  | 
| 783 | returns: | 
| 784 | qh.newfacet_list with full neighbor sets | 
| 785 | get vertices with nth neighbor by deleting nth vertex | 
| 786 | if qh.PREmerge/MERGEexact or qh.FORCEoutput | 
| 787 | sets facet->flippped if flipped normal (also prevents point partitioning) | 
| 788 | if duplicate ridges and qh.PREmerge/MERGEexact | 
| 789 | sets facet->dupridge | 
| 790 | missing neighbor links identifies extra ridges to be merging (qh_MERGEridge) | 
| 791 |  | 
| 792 | notes: | 
| 793 | newfacets already have neighbor[0] (horizon facet) | 
| 794 | assumes qh.hash_table is NULL | 
| 795 | vertex->neighbors has not been updated yet | 
| 796 | do not allocate memory after qh.hash_table (need to free it cleanly) | 
| 797 |  | 
| 798 | design: | 
| 799 | delete neighbor sets for all new facets | 
| 800 | initialize a hash table | 
| 801 | for all new facets | 
| 802 | match facet with neighbors | 
| 803 | if unmatched facets (due to duplicate ridges) | 
| 804 | for each new facet with a duplicate ridge | 
| 805 | match it with a facet | 
| 806 | check for flipped facets | 
| 807 | */ | 
| 808 | void qh_matchnewfacets (void /* qh newfacet_list */) { | 
| 809 | int numnew=0, hashcount=0, newskip; | 
| 810 | facetT *newfacet, *neighbor; | 
| 811 | int dim= qh hull_dim, hashsize, neighbor_i, neighbor_n; | 
| 812 | setT *neighbors; | 
| 813 | #ifndef qh_NOtrace | 
| 814 | int facet_i, facet_n, numfree= 0; | 
| 815 | facetT *facet; | 
| 816 | #endif | 
| 817 |  | 
| 818 | trace1((qh ferr, "qh_matchnewfacets: match neighbors for new facets.\n")); | 
| 819 | FORALLnew_facets { | 
| 820 | numnew++; | 
| 821 | {  /* inline qh_setzero (newfacet->neighbors, 1, qh hull_dim); */ | 
| 822 | neighbors= newfacet->neighbors; | 
| 823 | neighbors->e[neighbors->maxsize].i= dim+1; /*may be overwritten*/ | 
| 824 | memset ((char *)SETelemaddr_(neighbors, 1, void), 0, dim * SETelemsize); | 
| 825 | } | 
| 826 | } | 
| 827 | qh_newhashtable (numnew*(qh hull_dim-1)); /* twice what is normally needed, | 
| 828 | but every ridge could be DUPLICATEridge */ | 
| 829 | hashsize= qh_setsize (qh hash_table); | 
| 830 | FORALLnew_facets { | 
| 831 | for (newskip=1; newskip<qh hull_dim; newskip++) /* furthest/horizon already matched */ | 
| 832 | qh_matchneighbor (newfacet, newskip, hashsize, &hashcount); | 
| 833 | #if 0 | 
| 834 | /* use the following to trap hashcount errors */ | 
| 835 | { | 
| 836 | int count= 0, k; | 
| 837 | facetT *facet, *neighbor; | 
| 838 |  | 
| 839 | count= 0; | 
| 840 | FORALLfacet_(qh newfacet_list) {  /* newfacet already in use */ | 
| 841 | for (k=1; k < qh hull_dim; k++) { | 
| 842 | neighbor= SETelemt_(facet->neighbors, k, facetT); | 
| 843 | if (!neighbor || neighbor == qh_DUPLICATEridge) | 
| 844 | count++; | 
| 845 | } | 
| 846 | if (facet == newfacet) | 
| 847 | break; | 
| 848 | } | 
| 849 | if (count != hashcount) { | 
| 850 | fprintf (qh ferr, "qh_matchnewfacets: after adding facet %d, hashcount %d != count %d\n", | 
| 851 | newfacet->id, hashcount, count); | 
| 852 | qh_errexit (qh_ERRqhull, newfacet, NULL); | 
| 853 | } | 
| 854 | } | 
| 855 | #endif  /* end of trap code */ | 
| 856 | } | 
| 857 | if (hashcount) { | 
| 858 | FORALLnew_facets { | 
| 859 | if (newfacet->dupridge) { | 
| 860 | FOREACHneighbor_i_(newfacet) { | 
| 861 | if (neighbor == qh_DUPLICATEridge) { | 
| 862 | qh_matchduplicates (newfacet, neighbor_i, hashsize, &hashcount); | 
| 863 | /* this may report MERGEfacet */ | 
| 864 | } | 
| 865 | } | 
| 866 | } | 
| 867 | } | 
| 868 | } | 
| 869 | if (hashcount) { | 
| 870 | fprintf (qh ferr, "qhull internal error (qh_matchnewfacets): %d neighbors did not match up\n", | 
| 871 | hashcount); | 
| 872 | qh_printhashtable (qh ferr); | 
| 873 | qh_errexit (qh_ERRqhull, NULL, NULL); | 
| 874 | } | 
| 875 | #ifndef qh_NOtrace | 
| 876 | if (qh IStracing >= 2) { | 
| 877 | FOREACHfacet_i_(qh hash_table) { | 
| 878 | if (!facet) | 
| 879 | numfree++; | 
| 880 | } | 
| 881 | fprintf (qh ferr, "qh_matchnewfacets: %d new facets, %d unused hash entries .  hashsize %d\n", | 
| 882 | numnew, numfree, qh_setsize (qh hash_table)); | 
| 883 | } | 
| 884 | #endif /* !qh_NOtrace */ | 
| 885 | qh_setfree (&qh hash_table); | 
| 886 | if (qh PREmerge || qh MERGEexact) { | 
| 887 | if (qh IStracing >= 4) | 
| 888 | qh_printfacetlist (qh newfacet_list, NULL, qh_ALL); | 
| 889 | FORALLnew_facets { | 
| 890 | if (newfacet->normal) | 
| 891 | qh_checkflipped (newfacet, NULL, qh_ALL); | 
| 892 | } | 
| 893 | }else if (qh FORCEoutput) | 
| 894 | qh_checkflipped_all (qh newfacet_list);  /* prints warnings for flipped */ | 
| 895 | } /* matchnewfacets */ | 
| 896 |  | 
| 897 |  | 
| 898 | /*-<a                             href="qh-poly.htm#TOC" | 
| 899 | >-------------------------------</a><a name="matchvertices">-</a> | 
| 900 |  | 
| 901 | qh_matchvertices( firstindex, verticesA, skipA, verticesB, skipB, same ) | 
| 902 | tests whether vertices match with a single skip | 
| 903 | starts match at firstindex since all new facets have a common vertex | 
| 904 |  | 
| 905 | returns: | 
| 906 | true if matched vertices | 
| 907 | skip index for each set | 
| 908 | sets same iff vertices have the same orientation | 
| 909 |  | 
| 910 | notes: | 
| 911 | assumes skipA is in A and both sets are the same size | 
| 912 |  | 
| 913 | design: | 
| 914 | set up pointers | 
| 915 | scan both sets checking for a match | 
| 916 | test orientation | 
| 917 | */ | 
| 918 | boolT qh_matchvertices (int firstindex, setT *verticesA, int skipA, | 
| 919 | setT *verticesB, int *skipB, boolT *same) { | 
| 920 | vertexT **elemAp, **elemBp, **skipBp=NULL, **skipAp; | 
| 921 |  | 
| 922 | elemAp= SETelemaddr_(verticesA, firstindex, vertexT); | 
| 923 | elemBp= SETelemaddr_(verticesB, firstindex, vertexT); | 
| 924 | skipAp= SETelemaddr_(verticesA, skipA, vertexT); | 
| 925 | do if (elemAp != skipAp) { | 
| 926 | while (*elemAp != *elemBp++) { | 
| 927 | if (skipBp) | 
| 928 | return False; | 
| 929 | skipBp= elemBp;  /* one extra like FOREACH */ | 
| 930 | } | 
| 931 | }while(*(++elemAp)); | 
| 932 | if (!skipBp) | 
| 933 | skipBp= ++elemBp; | 
| 934 | *skipB= SETindex_(verticesB, skipB); | 
| 935 | *same= !(((ptr_intT)skipA & 0x1) ^ ((ptr_intT)*skipB & 0x1)); | 
| 936 | trace4((qh ferr, "qh_matchvertices: matched by skip %d (v%d) and skip %d (v%d) same? %d\n", skipA, (*skipAp)->id, *skipB, (*(skipBp-1))->id, *same)); | 
| 937 | return (True); | 
| 938 | } /* matchvertices */ | 
| 939 |  | 
| 940 | /*-<a                             href="qh-poly.htm#TOC" | 
| 941 | >-------------------------------</a><a name="newfacet">-</a> | 
| 942 |  | 
| 943 | qh_newfacet() | 
| 944 | return a new facet | 
| 945 |  | 
| 946 | returns: | 
| 947 | all fields initialized or cleared   (NULL) | 
| 948 | preallocates neighbors set | 
| 949 | */ | 
| 950 | facetT *qh_newfacet(void) { | 
| 951 | facetT *facet; | 
| 952 | void **freelistp; /* used !qh_NOmem */ | 
| 953 |  | 
| 954 | qh_memalloc_(sizeof(facetT), freelistp, facet, facetT); | 
| 955 | memset ((char *)facet, 0, sizeof(facetT)); | 
| 956 | if (qh facet_id == qh tracefacet_id) | 
| 957 | qh tracefacet= facet; | 
| 958 | facet->id= qh facet_id++; | 
| 959 | facet->neighbors= qh_setnew(qh hull_dim); | 
| 960 | #if !qh_COMPUTEfurthest | 
| 961 | facet->furthestdist= 0.0; | 
| 962 | #endif | 
| 963 | #if qh_MAXoutside | 
| 964 | if (qh FORCEoutput && qh APPROXhull) | 
| 965 | facet->maxoutside= qh MINoutside; | 
| 966 | else | 
| 967 | facet->maxoutside= qh DISTround; | 
| 968 | #endif | 
| 969 | facet->simplicial= True; | 
| 970 | facet->good= True; | 
| 971 | facet->newfacet= True; | 
| 972 | trace4((qh ferr, "qh_newfacet: created facet f%d\n", facet->id)); | 
| 973 | return (facet); | 
| 974 | } /* newfacet */ | 
| 975 |  | 
| 976 |  | 
| 977 | /*-<a                             href="qh-poly.htm#TOC" | 
| 978 | >-------------------------------</a><a name="newridge">-</a> | 
| 979 |  | 
| 980 | qh_newridge() | 
| 981 | return a new ridge | 
| 982 | */ | 
| 983 | ridgeT *qh_newridge(void) { | 
| 984 | ridgeT *ridge; | 
| 985 | void **freelistp;   /* used !qh_NOmem */ | 
| 986 |  | 
| 987 | qh_memalloc_(sizeof(ridgeT), freelistp, ridge, ridgeT); | 
| 988 | memset ((char *)ridge, 0, sizeof(ridgeT)); | 
| 989 | zinc_(Ztotridges); | 
| 990 | if (qh ridge_id == 0xFFFFFF) { | 
| 991 | fprintf(qh ferr, "\ | 
| 992 | qhull warning: more than %d ridges.  ID field overflows and two ridges\n\ | 
| 993 | may have the same identifier.  Otherwise output ok.\n", 0xFFFFFF); | 
| 994 | } | 
| 995 | ridge->id= qh ridge_id++; | 
| 996 | trace4((qh ferr, "qh_newridge: created ridge r%d\n", ridge->id)); | 
| 997 | return (ridge); | 
| 998 | } /* newridge */ | 
| 999 |  | 
| 1000 |  | 
| 1001 | /*-<a                             href="qh-poly.htm#TOC" | 
| 1002 | >-------------------------------</a><a name="pointid">-</a> | 
| 1003 |  | 
| 1004 | qh_pointid(  ) | 
| 1005 | return id for a point, | 
| 1006 | returns -3 if null, -2 if interior, or -1 if not known | 
| 1007 |  | 
| 1008 | alternative code: | 
| 1009 | unsigned long id; | 
| 1010 | id= ((unsigned long)point - (unsigned long)qh.first_point)/qh.normal_size; | 
| 1011 |  | 
| 1012 | notes: | 
| 1013 | if point not in point array | 
| 1014 | the code does a comparison of unrelated pointers. | 
| 1015 | */ | 
| 1016 | int qh_pointid (pointT *point) { | 
| 1017 | long offset, id; | 
| 1018 |  | 
| 1019 | if (!point) | 
| 1020 | id= -3; | 
| 1021 | else if (point == qh interior_point) | 
| 1022 | id= -2; | 
| 1023 | else if (point >= qh first_point | 
| 1024 | && point < qh first_point + qh num_points * qh hull_dim) { | 
| 1025 | offset= point - qh first_point; | 
| 1026 | id= offset / qh hull_dim; | 
| 1027 | }else if ((id= qh_setindex (qh other_points, point)) != -1) | 
| 1028 | id += qh num_points; | 
| 1029 | else | 
| 1030 | id= -1; | 
| 1031 | return (int) id; | 
| 1032 | } /* pointid */ | 
| 1033 |  | 
| 1034 | /*-<a                             href="qh-poly.htm#TOC" | 
| 1035 | >-------------------------------</a><a name="removefacet">-</a> | 
| 1036 |  | 
| 1037 | qh_removefacet( facet ) | 
| 1038 | unlinks facet from qh.facet_list, | 
| 1039 |  | 
| 1040 | returns: | 
| 1041 | updates qh.facet_list .newfacet_list .facet_next visible_list | 
| 1042 | decrements qh.num_facets | 
| 1043 |  | 
| 1044 | see: | 
| 1045 | qh_appendfacet | 
| 1046 | */ | 
| 1047 | void qh_removefacet(facetT *facet) { | 
| 1048 | facetT *next= facet->next, *previous= facet->previous; | 
| 1049 |  | 
| 1050 | if (facet == qh newfacet_list) | 
| 1051 | qh newfacet_list= next; | 
| 1052 | if (facet == qh facet_next) | 
| 1053 | qh facet_next= next; | 
| 1054 | if (facet == qh visible_list) | 
| 1055 | qh visible_list= next; | 
| 1056 | if (previous) { | 
| 1057 | previous->next= next; | 
| 1058 | next->previous= previous; | 
| 1059 | }else {  /* 1st facet in qh facet_list */ | 
| 1060 | qh facet_list= next; | 
| 1061 | qh facet_list->previous= NULL; | 
| 1062 | } | 
| 1063 | qh num_facets--; | 
| 1064 | trace4((qh ferr, "qh_removefacet: remove f%d from facet_list\n", facet->id)); | 
| 1065 | } /* removefacet */ | 
| 1066 |  | 
| 1067 |  | 
| 1068 | /*-<a                             href="qh-poly.htm#TOC" | 
| 1069 | >-------------------------------</a><a name="removevertex">-</a> | 
| 1070 |  | 
| 1071 | qh_removevertex( vertex ) | 
| 1072 | unlinks vertex from qh.vertex_list, | 
| 1073 |  | 
| 1074 | returns: | 
| 1075 | updates qh.vertex_list .newvertex_list | 
| 1076 | decrements qh.num_vertices | 
| 1077 | */ | 
| 1078 | void qh_removevertex(vertexT *vertex) { | 
| 1079 | vertexT *next= vertex->next, *previous= vertex->previous; | 
| 1080 |  | 
| 1081 | if (vertex == qh newvertex_list) | 
| 1082 | qh newvertex_list= next; | 
| 1083 | if (previous) { | 
| 1084 | previous->next= next; | 
| 1085 | next->previous= previous; | 
| 1086 | }else {  /* 1st vertex in qh vertex_list */ | 
| 1087 | qh vertex_list= vertex->next; | 
| 1088 | qh vertex_list->previous= NULL; | 
| 1089 | } | 
| 1090 | qh num_vertices--; | 
| 1091 | trace4((qh ferr, "qh_removevertex: remove v%d from vertex_list\n", vertex->id)); | 
| 1092 | } /* removevertex */ | 
| 1093 |  | 
| 1094 |  | 
| 1095 | /*-<a                             href="qh-poly.htm#TOC" | 
| 1096 | >-------------------------------</a><a name="updatevertices">-</a> | 
| 1097 |  | 
| 1098 | qh_updatevertices() | 
| 1099 | update vertex neighbors and delete interior vertices | 
| 1100 |  | 
| 1101 | returns: | 
| 1102 | if qh.VERTEXneighbors, updates neighbors for each vertex | 
| 1103 | if qh.newvertex_list, | 
| 1104 | removes visible neighbors  from vertex neighbors | 
| 1105 | if qh.newfacet_list | 
| 1106 | adds new facets to vertex neighbors | 
| 1107 | if qh.visible_list | 
| 1108 | interior vertices added to qh.del_vertices for later partitioning | 
| 1109 |  | 
| 1110 | design: | 
| 1111 | if qh.VERTEXneighbors | 
| 1112 | deletes references to visible facets from vertex neighbors | 
| 1113 | appends new facets to the neighbor list for each vertex | 
| 1114 | checks all vertices of visible facets | 
| 1115 | removes visible facets from neighbor lists | 
| 1116 | marks unused vertices for deletion | 
| 1117 | */ | 
| 1118 | void qh_updatevertices (void /*qh newvertex_list, newfacet_list, visible_list*/) { | 
| 1119 | facetT *newfacet= NULL, *neighbor, **neighborp, *visible; | 
| 1120 | vertexT *vertex, **vertexp; | 
| 1121 |  | 
| 1122 | trace3((qh ferr, "qh_updatevertices: delete interior vertices and update vertex->neighbors\n")); | 
| 1123 | if (qh VERTEXneighbors) { | 
| 1124 | FORALLvertex_(qh newvertex_list) { | 
| 1125 | FOREACHneighbor_(vertex) { | 
| 1126 | if (neighbor->visible) | 
| 1127 | SETref_(neighbor)= NULL; | 
| 1128 | } | 
| 1129 | qh_setcompact (vertex->neighbors); | 
| 1130 | } | 
| 1131 | FORALLnew_facets { | 
| 1132 | FOREACHvertex_(newfacet->vertices) | 
| 1133 | qh_setappend (&vertex->neighbors, newfacet); | 
| 1134 | } | 
| 1135 | FORALLvisible_facets { | 
| 1136 | FOREACHvertex_(visible->vertices) { | 
| 1137 | if (!vertex->newlist && !vertex->deleted) { | 
| 1138 | FOREACHneighbor_(vertex) { /* this can happen under merging */ | 
| 1139 | if (!neighbor->visible) | 
| 1140 | break; | 
| 1141 | } | 
| 1142 | if (neighbor) | 
| 1143 | qh_setdel (vertex->neighbors, visible); | 
| 1144 | else { | 
| 1145 | vertex->deleted= True; | 
| 1146 | qh_setappend (&qh del_vertices, vertex); | 
| 1147 | trace2((qh ferr, "qh_updatevertices: delete vertex p%d (v%d) in f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); | 
| 1148 | } | 
| 1149 | } | 
| 1150 | } | 
| 1151 | } | 
| 1152 | }else {  /* !VERTEXneighbors */ | 
| 1153 | FORALLvisible_facets { | 
| 1154 | FOREACHvertex_(visible->vertices) { | 
| 1155 | if (!vertex->newlist && !vertex->deleted) { | 
| 1156 | vertex->deleted= True; | 
| 1157 | qh_setappend (&qh del_vertices, vertex); | 
| 1158 | trace2((qh ferr, "qh_updatevertices: delete vertex p%d (v%d) in f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); | 
| 1159 | } | 
| 1160 | } | 
| 1161 | } | 
| 1162 | } | 
| 1163 | } /* updatevertices */ | 
| 1164 |  | 
| 1165 |  | 
| 1166 |  |