/*
--------------------------------- poly.c implements polygons and simplices see qh-poly.htm, poly.h and libqhull.h infrequent code is in poly2.c (all but top 50 and their callers 12/3/95) Copyright (c) 1993-2020 The Geometry Center. $Id: //main/2019/qhull/src/libqhull/poly.c#7 $$Change: 2953 $ $DateTime: 2020/05/21 22:05:32 $$Author: bbarber $ */ #include "qhull_a.h" /*======== functions in alphabetical order ==========*/ /*--------------------------------- qh_appendfacet( facet ) appends facet to end of qh.facet_list, returns: updates qh.newfacet_list, facet_next, facet_list increments qh.numfacets notes: assumes qh.facet_list/facet_tail is defined (createsimplex) see: qh_removefacet() */ void qh_appendfacet(facetT *facet) { facetT *tail= qh facet_tail; if (tail == qh newfacet_list) { qh newfacet_list= facet; if (tail == qh visible_list) /* visible_list is at or before newfacet_list */ qh visible_list= facet; } if (tail == qh facet_next) qh facet_next= facet; facet->previous= tail->previous; facet->next= tail; if (tail->previous) tail->previous->next= facet; else qh facet_list= facet; tail->previous= facet; qh num_facets++; trace4((qh ferr, 4044, "qh_appendfacet: append f%d to facet_list\n", facet->id)); } /* appendfacet */ /*--------------------------------- qh_appendvertex( vertex ) appends vertex to end of qh.vertex_list, returns: sets vertex->newfacet updates qh.vertex_list, newvertex_list increments qh.num_vertices notes: assumes qh.vertex_list/vertex_tail is defined (createsimplex) */ void qh_appendvertex(vertexT *vertex) { vertexT *tail= qh vertex_tail; if (tail == qh newvertex_list) qh newvertex_list= vertex; vertex->newfacet= True; vertex->previous= tail->previous; vertex->next= tail; if (tail->previous) tail->previous->next= vertex; else qh vertex_list= vertex; tail->previous= vertex; qh num_vertices++; trace4((qh ferr, 4045, "qh_appendvertex: append v%d to qh.newvertex_list and set v.newfacet\n", vertex->id)); } /* appendvertex */ /*--------------------------------- qh_attachnewfacets( ) attach horizon facets to new facets in qh.newfacet_list newfacets have neighbor and ridge links to horizon but not vice versa returns: clears qh.NEWtentative set qh.NEWfacets horizon facets linked to new facets ridges changed from visible facets to new facets simplicial ridges deleted qh.visible_list, no ridges valid facet->f.replace is a newfacet (if any) notes: used for qh.NEWtentative, otherwise see qh_makenew_nonsimplicial and qh_makenew_simplicial qh_delridge_merge not needed (as tested by qh_checkdelridge) design: delete interior ridges and neighbor sets by for each visible, non-simplicial facet for each ridge if last visit or if neighbor is simplicial if horizon neighbor delete ridge for horizon's ridge set delete ridge erase neighbor set attach horizon facets and new facets by for all new facets if corresponding horizon facet is simplicial locate corresponding visible facet {may be more than one} link visible facet to new facet replace visible facet with new facet in horizon else it is non-simplicial for all visible neighbors of the horizon facet link visible neighbor to new facet delete visible neighbor from horizon facet append new facet to horizon's neighbors the first ridge of the new facet is the horizon ridge link the new facet into the horizon ridge */ void qh_attachnewfacets(void /* qh.visible_list, qh.newfacet_list */) { facetT *newfacet= NULL, *neighbor, **neighborp, *horizon, *visible; ridgeT *ridge, **ridgep; trace3((qh ferr, 3012, "qh_attachnewfacets: delete interior ridges\n")); if (qh CHECKfrequently) { qh_checkdelridge(); } qh visit_id++; FORALLvisible_facets { visible->visitid= qh visit_id; if (visible->ridges) { FOREACHridge_(visible->ridges) { neighbor= otherfacet_(ridge, visible); if (neighbor->visitid == qh visit_id || (!neighbor->visible && neighbor->simplicial)) { if (!neighbor->visible) /* delete ridge for simplicial horizon */ qh_setdel(neighbor->ridges, ridge); qh_delridge(ridge); /* delete on second visit */ } } } } trace1((qh ferr, 1017, "qh_attachnewfacets: attach horizon facets to new facets\n")); FORALLnew_facets { horizon= SETfirstt_(newfacet->neighbors, facetT); if (horizon->simplicial) { visible= NULL; FOREACHneighbor_(horizon) { /* may have more than one horizon ridge */ if (neighbor->visible) { if (visible) { if (qh_setequal_skip(newfacet->vertices, 0, horizon->vertices, SETindex_(horizon->neighbors, neighbor))) { visible= neighbor; break; } }else visible= neighbor; } } if (visible) { visible->f.replace= newfacet; qh_setreplace(horizon->neighbors, visible, newfacet); }else { qh_fprintf(qh ferr, 6102, "qhull internal error (qh_attachnewfacets): could not find visible facet for horizon f%d of newfacet f%d\n", horizon->id, newfacet->id); qh_errexit2(qh_ERRqhull, horizon, newfacet); } }else { /* non-simplicial, with a ridge for newfacet */ FOREACHneighbor_(horizon) { /* may hold for many new facets */ if (neighbor->visible) { neighbor->f.replace= newfacet; qh_setdelnth(horizon->neighbors, SETindex_(horizon->neighbors, neighbor)); neighborp--; /* repeat */ } } qh_setappend(&horizon->neighbors, newfacet); ridge= SETfirstt_(newfacet->ridges, ridgeT); if (ridge->top == horizon) { ridge->bottom= newfacet; ridge->simplicialbot= True; }else { ridge->top= newfacet; ridge->simplicialtop= True; } } } /* newfacets */ trace4((qh ferr, 4094, "qh_attachnewfacets: clear f.ridges and f.neighbors for visible facets, may become invalid before qh_deletevisible\n")); FORALLvisible_facets { if (visible->ridges) SETfirst_(visible->ridges)= NULL; SETfirst_(visible->neighbors)= NULL; } qh NEWtentative= False; qh NEWfacets= True; if (qh PRINTstatistics) { FORALLvisible_facets { if (!visible->f.replace) zinc_(Zinsidevisible); } } } /* attachnewfacets */ /*--------------------------------- qh_checkflipped( facet, dist, allerror ) checks facet orientation to interior point if allerror set, tests against -qh.DISTround else tests against 0.0 since tested against -qh.DISTround before returns: False if it flipped orientation (sets facet->flipped) distance if non-NULL notes: called by qh_setfacetplane, qh_initialhull, and qh_checkflipped_all */ boolT qh_checkflipped(facetT *facet, realT *distp, boolT allerror) { realT dist; if (facet->flipped && !distp) return False; zzinc_(Zdistcheck); qh_distplane(qh interior_point, facet, &dist); if (distp) *distp= dist; if ((allerror && dist >= -qh DISTround) || (!allerror && dist > 0.0)) { facet->flipped= True; trace0((qh ferr, 19, "qh_checkflipped: facet f%d flipped, allerror? %d, distance= %6.12g during p%d\n", facet->id, allerror, dist, qh furthest_id)); if (qh num_facets > qh hull_dim+1) { /* qh_initialhull reverses orientation if !qh_checkflipped */ zzinc_(Zflippedfacets); qh_joggle_restart("flipped facet"); } return False; } return True; } /* checkflipped */ /*--------------------------------- qh_delfacet( facet ) removes facet from facet_list and frees up its memory notes: assumes vertices and ridges already freed or referenced elsewhere */ void qh_delfacet(facetT *facet) { void **freelistp; /* used if !qh_NOmem by qh_memfree_() */ trace3((qh ferr, 3057, "qh_delfacet: delete f%d\n", facet->id)); if (qh CHECKfrequently || qh VERIFYoutput) { if (!qh NOerrexit) { qh_checkdelfacet(facet, qh facet_mergeset); qh_checkdelfacet(facet, qh degen_mergeset); qh_checkdelfacet(facet, qh vertex_mergeset); } } if (facet == qh tracefacet) qh tracefacet= NULL; if (facet == qh GOODclosest) qh GOODclosest= NULL; qh_removefacet(facet); if (!facet->tricoplanar || facet->keepcentrum) { qh_memfree_(facet->normal, qh normal_size, freelistp); if (qh CENTERtype == qh_ASvoronoi) { /* braces for macro calls */ qh_memfree_(facet->center, qh center_size, freelistp); }else /* AScentrum */ { qh_memfree_(facet->center, qh normal_size, freelistp); } } qh_setfree(&(facet->neighbors)); if (facet->ridges) qh_setfree(&(facet->ridges)); qh_setfree(&(facet->vertices)); if (facet->outsideset) qh_setfree(&(facet->outsideset)); if (facet->coplanarset) qh_setfree(&(facet->coplanarset)); qh_memfree_(facet, (int)sizeof(facetT), freelistp); } /* delfacet */ /*--------------------------------- qh_deletevisible() delete visible facets and vertices returns: deletes each facet and removes from facetlist deletes vertices on qh.del_vertices and ridges in qh.del_ridges at exit, qh.visible_list empty (== qh.newfacet_list) notes: called by qh_all_vertexmerges, qh_addpoint, and qh_qhull ridges already deleted or moved elsewhere deleted vertices on qh.del_vertices horizon facets do not reference facets on qh.visible_list new facets in qh.newfacet_list uses qh.visit_id; */ void qh_deletevisible(void /* qh.visible_list */) { facetT *visible, *nextfacet; vertexT *vertex, **vertexp; int numvisible= 0, numdel= qh_setsize(qh del_vertices); trace1((qh ferr, 1018, "qh_deletevisible: delete %d visible facets and %d vertices\n", qh num_visible, numdel)); for (visible=qh visible_list; visible && visible->visible; visible= nextfacet) { /* deleting current */ nextfacet= visible->next; numvisible++; qh_delfacet(visible); /* f.ridges deleted or moved elsewhere, deleted f.vertices on qh.del_vertices */ } if (numvisible != qh num_visible) { qh_fprintf(qh ferr, 6103, "qhull internal error (qh_deletevisible): qh num_visible %d is not number of visible facets %d\n", qh num_visible, numvisible); qh_errexit(qh_ERRqhull, NULL, NULL); } qh num_visible= 0; zadd_(Zvisfacettot, numvisible); zmax_(Zvisfacetmax, numvisible); zzadd_(Zdelvertextot, numdel); zmax_(Zdelvertexmax, numdel); FOREACHvertex_(qh del_vertices) qh_delvertex(vertex); qh_settruncate(qh del_vertices, 0); } /* deletevisible */ /*--------------------------------- qh_facetintersect( facetA, facetB, skipa, skipB, prepend ) return vertices for intersection of two simplicial facets may include 1 prepended entry (if more, need to settemppush) returns: returns set of qh.hull_dim-1 + prepend vertices returns skipped index for each test and checks for exactly one notes: does not need settemp since set in quick memory see also: qh_vertexintersect and qh_vertexintersect_new use qh_setnew_delnthsorted to get nth ridge (no skip information) design: locate skipped vertex by scanning facet A's neighbors locate skipped vertex by scanning facet B's neighbors intersect the vertex sets */ setT *qh_facetintersect(facetT *facetA, facetT *facetB, int *skipA,int *skipB, int prepend) { setT *intersect; int dim= qh hull_dim, i, j; facetT **neighborsA, **neighborsB; neighborsA= SETaddr_(facetA->neighbors, facetT); neighborsB= SETaddr_(facetB->neighbors, facetT); i= j= 0; if (facetB == *neighborsA++) *skipA= 0; else if (facetB == *neighborsA++) *skipA= 1; else if (facetB == *neighborsA++) *skipA= 2; else { for (i=3; i < dim; i++) { if (facetB == *neighborsA++) { *skipA= i; break; } } } if (facetA == *neighborsB++) *skipB= 0; else if (facetA == *neighborsB++) *skipB= 1; else if (facetA == *neighborsB++) *skipB= 2; else { for (j=3; j < dim; j++) { if (facetA == *neighborsB++) { *skipB= j; break; } } } if (i >= dim || j >= dim) { qh_fprintf(qh ferr, 6104, "qhull internal error (qh_facetintersect): f%d or f%d not in other's neighbors\n", facetA->id, facetB->id); qh_errexit2(qh_ERRqhull, facetA, facetB); } intersect= qh_setnew_delnthsorted(facetA->vertices, qh hull_dim, *skipA, prepend); trace4((qh ferr, 4047, "qh_facetintersect: f%d skip %d matches f%d skip %d\n", facetA->id, *skipA, facetB->id, *skipB)); return(intersect); } /* facetintersect */ /*--------------------------------- qh_gethash( hashsize, set, size, firstindex, skipelem ) return hashvalue for a set with firstindex and skipelem notes: returned hash is in [0,hashsize) assumes at least firstindex+1 elements assumes skipelem is NULL, in set, or part of hash hashes memory addresses which may change over different runs of the same data using sum for hash does badly in high d */ int qh_gethash(int hashsize, setT *set, int size, int firstindex, void *skipelem) { void **elemp= SETelemaddr_(set, firstindex, void); ptr_intT hash= 0, elem; unsigned int uresult; int i; #ifdef _MSC_VER /* Microsoft Visual C++ -- warn about 64-bit issues */ #pragma warning( push) /* WARN64 -- ptr_intT holds a 64-bit pointer */ #pragma warning( disable : 4311) /* 'type cast': pointer truncation from 'void*' to 'ptr_intT' */ #endif switch (size-firstindex) { case 1: hash= (ptr_intT)(*elemp) - (ptr_intT) skipelem; break; case 2: hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] - (ptr_intT) skipelem; break; case 3: hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] - (ptr_intT) skipelem; break; case 4: hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] + (ptr_intT)elemp[3] - (ptr_intT) skipelem; break; case 5: hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] + (ptr_intT)elemp[3] + (ptr_intT)elemp[4] - (ptr_intT) skipelem; break; case 6: hash= (ptr_intT)(*elemp) + (ptr_intT)elemp[1] + (ptr_intT)elemp[2] + (ptr_intT)elemp[3] + (ptr_intT)elemp[4]+ (ptr_intT)elemp[5] - (ptr_intT) skipelem; break; default: hash= 0; i= 3; do { /* this is about 10% in 10-d */ if ((elem= (ptr_intT)*elemp++) != (ptr_intT)skipelem) { hash ^= (elem << i) + (elem >> (32-i)); i += 3; if (i >= 32) i -= 32; } }while (*elemp); break; } if (hashsize<0) { qh_fprintf(qh ferr, 6202, "qhull internal error: negative hashsize %d passed to qh_gethash [poly.c]\n", hashsize); qh_errexit2(qh_ERRqhull, NULL, NULL); } uresult= (unsigned int)hash; uresult %= (unsigned int)hashsize; /* result= 0; for debugging */ return (int)uresult; #ifdef _MSC_VER #pragma warning( pop) #endif } /* gethash */ /*--------------------------------- qh_getreplacement( visible ) get replacement for visible facet returns: valid facet from visible.replace (may be chained) */ facetT *qh_getreplacement(facetT *visible) { unsigned int count= 0; facetT *result= visible; while (result && result->visible) { result= result->f.replace; if (count++ > qh facet_id) qh_infiniteloop(visible); } return result; } /*--------------------------------- qh_makenewfacet( vertices, toporient, horizon ) creates a toporient? facet from vertices returns: returns newfacet adds newfacet to qh.facet_list newfacet->vertices= vertices if horizon newfacet->neighbor= horizon, but not vice versa newvertex_list updated with vertices */ facetT *qh_makenewfacet(setT *vertices, boolT toporient, facetT *horizon) { facetT *newfacet; vertexT *vertex, **vertexp; FOREACHvertex_(vertices) { if (!vertex->newfacet) { qh_removevertex(vertex); qh_appendvertex(vertex); } } newfacet= qh_newfacet(); newfacet->vertices= vertices; if (toporient) newfacet->toporient= True; if (horizon) qh_setappend(&(newfacet->neighbors), horizon); qh_appendfacet(newfacet); return(newfacet); } /* makenewfacet */ /*--------------------------------- qh_makenewplanes() make new hyperplanes for facets on qh.newfacet_list returns: all facets have hyperplanes or are marked for merging doesn't create hyperplane if horizon is coplanar (will merge) updates qh.min_vertex if qh.JOGGLEmax notes: facet->f.samecycle is defined for facet->mergehorizon facets */ void qh_makenewplanes(void /* qh.newfacet_list */) { facetT *newfacet; trace4((qh ferr, 4074, "qh_makenewplanes: make new hyperplanes for facets on qh.newfacet_list f%d\n", qh newfacet_list->id)); FORALLnew_facets { if (!newfacet->mergehorizon) qh_setfacetplane(newfacet); /* updates Wnewvertexmax */ } if (qh JOGGLEmax < REALmax/2) minimize_(qh min_vertex, -wwval_(Wnewvertexmax)); } /* makenewplanes */ #ifndef qh_NOmerge /*--------------------------------- qh_makenew_nonsimplicial( visible, apex, numnew ) make new facets for ridges of a visible facet returns: first newfacet, bumps numnew as needed attaches new facets if !qh NEWtentative marks ridge neighbors for simplicial visible if (qh.NEWtentative) ridges on newfacet, horizon, and visible else ridge and neighbors between newfacet and horizon visible facet's ridges are deleted visible facet's f.neighbors is empty notes: called by qh_makenewfacets and qh_triangulatefacet qh.visit_id if visible has already been processed sets neighbor->seen for building f.samecycle assumes all 'seen' flags initially false qh_delridge_merge not needed (as tested by qh_checkdelridge in qh_makenewfacets) design: for each ridge of visible facet get neighbor of visible facet if neighbor was already processed delete the ridge (will delete all visible facets later) if neighbor is a horizon facet create a new facet if neighbor coplanar adds newfacet to f.samecycle for later merging else updates neighbor's neighbor set (checks for non-simplicial facet with multiple ridges to visible facet) updates neighbor's ridge set (checks for simplicial neighbor to non-simplicial visible facet) (deletes ridge if neighbor is simplicial) */ facetT *qh_makenew_nonsimplicial(facetT *visible, vertexT *apex, int *numnew) { void **freelistp; /* used if !qh_NOmem by qh_memfree_() */ ridgeT *ridge, **ridgep; facetT *neighbor, *newfacet= NULL, *samecycle; setT *vertices; boolT toporient; unsigned int ridgeid; FOREACHridge_(visible->ridges) { ridgeid= ridge->id; neighbor= otherfacet_(ridge, visible); if (neighbor->visible) { if (!qh NEWtentative) { if (neighbor->visitid == qh visit_id) { if (qh traceridge == ridge) qh traceridge= NULL; qh_setfree(&(ridge->vertices)); /* delete on 2nd visit */ qh_memfree_(ridge, (int)sizeof(ridgeT), freelistp); } } }else { /* neighbor is an horizon facet */ toporient= (ridge->top == visible); vertices= qh_setnew(qh hull_dim); /* makes sure this is quick */ qh_setappend(&vertices, apex); qh_setappend_set(&vertices, ridge->vertices); newfacet= qh_makenewfacet(vertices, toporient, neighbor); (*numnew)++; if (neighbor->coplanarhorizon) { newfacet->mergehorizon= True; if (!neighbor->seen) { newfacet->f.samecycle= newfacet; neighbor->f.newcycle= newfacet; }else { samecycle= neighbor->f.newcycle; newfacet->f.samecycle= samecycle->f.samecycle; samecycle->f.samecycle= newfacet; } } if (qh NEWtentative) { if (!neighbor->simplicial) qh_setappend(&(newfacet->ridges), ridge); }else { /* qh_attachnewfacets */ if (neighbor->seen) { if (neighbor->simplicial) { qh_fprintf(qh ferr, 6105, "qhull internal error (qh_makenew_nonsimplicial): simplicial f%d sharing two ridges with f%d\n", neighbor->id, visible->id); qh_errexit2(qh_ERRqhull, neighbor, visible); } qh_setappend(&(neighbor->neighbors), newfacet); }else qh_setreplace(neighbor->neighbors, visible, newfacet); if (neighbor->simplicial) { qh_setdel(neighbor->ridges, ridge); qh_delridge(ridge); }else { qh_setappend(&(newfacet->ridges), ridge); if (toporient) { ridge->top= newfacet; ridge->simplicialtop= True; }else { ridge->bottom= newfacet; ridge->simplicialbot= True; } } } trace4((qh ferr, 4048, "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)); } neighbor->seen= True; } /* for each ridge */ return newfacet; } /* makenew_nonsimplicial */ #else /* qh_NOmerge */ facetT *qh_makenew_nonsimplicial(facetT *visible, vertexT *apex, int *numnew) { QHULL_UNUSED(visible) QHULL_UNUSED(apex) QHULL_UNUSED(numnew) return NULL; } #endif /* qh_NOmerge */ /*--------------------------------- qh_makenew_simplicial( visible, apex, numnew ) make new facets for simplicial visible facet and apex returns: attaches new facets if !qh.NEWtentative neighbors between newfacet and horizon notes: nop if neighbor->seen or neighbor->visible(see qh_makenew_nonsimplicial) design: locate neighboring horizon facet for visible facet determine vertices and orientation create new facet if coplanar, add new facet to f.samecycle update horizon facet's neighbor list */ facetT *qh_makenew_simplicial(facetT *visible, vertexT *apex, int *numnew) { facetT *neighbor, **neighborp, *newfacet= NULL; setT *vertices; boolT flip, toporient; int horizonskip= 0, visibleskip= 0; FOREACHneighbor_(visible) { if (!neighbor->seen && !neighbor->visible) { vertices= qh_facetintersect(neighbor,visible, &horizonskip, &visibleskip, 1); SETfirst_(vertices)= apex; flip= ((horizonskip & 0x1) ^ (visibleskip & 0x1)); if (neighbor->toporient) toporient= horizonskip & 0x1; else toporient= (horizonskip & 0x1) ^ 0x1; newfacet= qh_makenewfacet(vertices, toporient, neighbor); (*numnew)++; if (neighbor->coplanarhorizon && (qh PREmerge || qh MERGEexact)) { #ifndef qh_NOmerge newfacet->f.samecycle= newfacet; newfacet->mergehorizon= True; #endif } if (!qh NEWtentative) SETelem_(neighbor->neighbors, horizonskip)= newfacet; trace4((qh ferr, 4049, "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)); } } return newfacet; } /* makenew_simplicial */ /*--------------------------------- qh_matchneighbor( newfacet, newskip, hashsize, hashcount ) either match subridge of newfacet with neighbor or add to hash_table returns: matched ridges of newfacet, except for duplicate ridges duplicate ridges marked by qh_DUPLICATEridge for qh_matchdupridge notes: called by qh_matchnewfacets assumes newfacet is simplicial ridge is newfacet->vertices w/o newskip vertex do not allocate memory (need to free hash_table cleanly) uses linear hash chains see qh_matchdupridge (poly2.c) design: for each possible matching facet in qh.hash_table if vertices match set ismatch, if facets have opposite orientation if ismatch and matching facet doesn't have a match match the facets by updating their neighbor sets else note: dupridge detected when a match 'f&d skip %d' has already been seen need to mark all of the dupridges for qh_matchdupridge indicate a duplicate ridge by qh_DUPLICATEridge and f.dupridge add facet to hashtable unless the other facet was already a duplicate ridge mark both facets with a duplicate ridge add other facet (if defined) to hash table state at "indicate a duplicate ridge": newfacet@newskip= the argument facet= the hashed facet@skip that has the same vertices as newfacet@newskip same= true if matched vertices have the same orientation matchfacet= neighbor at facet@skip matchfacet=qh_DUPLICATEridge, matchfacet was previously detected as a dupridge of facet@skip ismatch if 'vertex orientation (same) matches facet/newfacet orientation (toporient) unknown facet will match later details at "indicate a duplicate ridge": if !ismatch and matchfacet, dupridge is between hashed facet@skip/matchfacet@matchskip and arg newfacet@newskip/unknown set newfacet@newskip, facet@skip, and matchfacet@matchskip to qh_DUPLICATEridge add newfacet and matchfacet to hash_table if ismatch and matchfacet, same as !ismatch and matchfacet -- it matches facet instead of matchfacet if !ismatch and !matchfacet dupridge between hashed facet@skip/unknown and arg newfacet@newskip/unknown set newfacet@newskip and facet@skip to qh_DUPLICATEridge add newfacet to hash_table if ismatch and matchfacet==qh_DUPLICATEridge dupridge with already duplicated hashed facet@skip and arg newfacet@newskip/unknown set newfacet@newskip to qh_DUPLICATEridge add newfacet to hash_table facet's hyperplane already set */ void qh_matchneighbor(facetT *newfacet, int newskip, int hashsize, int *hashcount) { boolT newfound= False; /* True, if new facet is already in hash chain */ boolT same, ismatch; int hash, scan; facetT *facet, *matchfacet; int skip, matchskip; hash= qh_gethash(hashsize, newfacet->vertices, qh hull_dim, 1, SETelem_(newfacet->vertices, newskip)); trace4((qh ferr, 4050, "qh_matchneighbor: newfacet f%d skip %d hash %d hashcount %d\n", newfacet->id, newskip, hash, *hashcount)); zinc_(Zhashlookup); for (scan=hash; (facet= SETelemt_(qh hash_table, scan, facetT)); scan= (++scan >= hashsize ? 0 : scan)) { if (facet == newfacet) { newfound= True; continue; } zinc_(Zhashtests); if (qh_matchvertices(1, newfacet->vertices, newskip, facet->vertices, &skip, &same)) { if (SETelem_(newfacet->vertices, newskip) == SETelem_(facet->vertices, skip)) { qh_joggle_restart("two new facets with the same vertices"); /* duplicated for multiple skips, not easily avoided */ qh_fprintf(qh ferr, 7084, "qhull topology warning (qh_matchneighbor): will merge vertices to undo new facets -- f%d and f%d have the same vertices (skip %d, skip %d) and same horizon ridges to f%d and f%d\n", facet->id, newfacet->id, skip, newskip, SETfirstt_(facet->neighbors, facetT)->id, SETfirstt_(newfacet->neighbors, facetT)->id); /* will rename a vertex (QH3053). The fault was duplicate ridges (same vertices) in different facets due to a previous rename. Expensive to detect beforehand */ } ismatch= (same == (boolT)((newfacet->toporient ^ facet->toporient))); matchfacet= SETelemt_(facet->neighbors, skip, facetT); if (ismatch && !matchfacet) { SETelem_(facet->neighbors, skip)= newfacet; SETelem_(newfacet->neighbors, newskip)= facet; (*hashcount)--; trace4((qh ferr, 4051, "qh_matchneighbor: f%d skip %d matched with new f%d skip %d\n", facet->id, skip, newfacet->id, newskip)); return; } if (!qh PREmerge && !qh MERGEexact) { qh_joggle_restart("a ridge with more than two neighbors"); qh_fprintf(qh ferr, 6107, "qhull topology error: facets f%d, f%d and f%d meet at a ridge with more than 2 neighbors. Can not continue due to no qh.PREmerge and no 'Qx' (MERGEexact)\n", facet->id, newfacet->id, getid_(matchfacet)); qh_errexit2(qh_ERRtopology, facet, newfacet); } SETelem_(newfacet->neighbors, newskip)= qh_DUPLICATEridge; newfacet->dupridge= True; qh_addhash(newfacet, qh hash_table, hashsize, hash); (*hashcount)++; if (matchfacet != qh_DUPLICATEridge) { SETelem_(facet->neighbors, skip)= qh_DUPLICATEridge; facet->dupridge= True; if (matchfacet) { matchskip= qh_setindex(matchfacet->neighbors, facet); if (matchskip<0) { qh_fprintf(qh ferr, 6260, "qhull topology error (qh_matchneighbor): matchfacet f%d is in f%d neighbors but not vice versa. Can not continue.\n", matchfacet->id, facet->id); qh_errexit2(qh_ERRtopology, matchfacet, facet); } SETelem_(matchfacet->neighbors, matchskip)= qh_DUPLICATEridge; /* matchskip>=0 by QH6260 */ matchfacet->dupridge= True; qh_addhash(matchfacet, qh hash_table, hashsize, hash); *hashcount += 2; } } trace4((qh ferr, 4052, "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)); return; /* end of duplicate ridge */ } } if (!newfound) SETelem_(qh hash_table, scan)= newfacet; /* same as qh_addhash */ (*hashcount)++; trace4((qh ferr, 4053, "qh_matchneighbor: no match for f%d skip %d at hash %d\n", newfacet->id, newskip, hash)); } /* matchneighbor */ /*--------------------------------- qh_matchnewfacets( ) match new facets in qh.newfacet_list to their newfacet neighbors all facets are simplicial returns: if dupridges and merging returns maxdupdist (>=0.0) from vertex to opposite facet sets facet->dupridge missing neighbor links identify dupridges to be merged (qh_DUPLICATEridge) else qh.newfacet_list with full neighbor sets vertices for the nth neighbor match all but the nth vertex if not merging and qh.FORCEoutput for facets with normals (i.e., with dupridges) sets facet->flippped for flipped normals, also prevents point partitioning notes: called by qh_buildcone* and qh_triangulate_facet neighbor[0] of new facets is the horizon facet if NEWtentative, new facets not attached to the horizon assumes qh.hash_table is NULL vertex->neighbors has not been updated yet do not allocate memory after qh.hash_table (need to free it cleanly) design: truncate neighbor sets to horizon facet for all new facets initialize a hash table for all new facets match facet with neighbors if unmatched facets (due to duplicate ridges) for each new facet with a duplicate ridge try to match facets with the same coplanar horizon if not all matched for each new facet with a duplicate ridge match it with a coplanar facet, or identify a pinched vertex if not merging and qh.FORCEoutput check for flipped facets */ coordT qh_matchnewfacets(void /* qh.newfacet_list */) { int numnew=0, hashcount=0, newskip; facetT *newfacet, *neighbor; coordT maxdupdist= 0.0, maxdist2; int dim= qh hull_dim, hashsize, neighbor_i, neighbor_n; setT *neighbors; #ifndef qh_NOtrace int facet_i, facet_n, numunused= 0; facetT *facet; #endif trace1((qh ferr, 1019, "qh_matchnewfacets: match neighbors for new facets.\n")); FORALLnew_facets { numnew++; { /* inline qh_setzero(newfacet->neighbors, 1, qh hull_dim); */ neighbors= newfacet->neighbors; neighbors->e[neighbors->maxsize].i= dim+1; /*may be overwritten*/ memset((char *)SETelemaddr_(neighbors, 1, void), 0, (size_t)(dim * SETelemsize)); } } qh_newhashtable(numnew*(qh hull_dim-1)); /* twice what is normally needed, but every ridge could be DUPLICATEridge */ hashsize= qh_setsize(qh hash_table); FORALLnew_facets { if (!newfacet->simplicial) { qh_fprintf(qh ferr, 6377, "qhull internal error (qh_matchnewfacets): expecting simplicial facets on qh.newfacet_list f%d for qh_matchneighbors, qh_matchneighbor, and qh_matchdupridge. Got non-simplicial f%d\n", qh newfacet_list->id, newfacet->id); qh_errexit2(qh_ERRqhull, newfacet, qh newfacet_list); } for (newskip=1; newskip0 because hull_dim>1 and numnew>0 */ qh_matchneighbor(newfacet, newskip, hashsize, &hashcount); #if 0 /* use the following to trap hashcount errors */ { int count= 0, k; facetT *facet, *neighbor; count= 0; FORALLfacet_(qh newfacet_list) { /* newfacet already in use */ for (k=1; k < qh hull_dim; k++) { neighbor= SETelemt_(facet->neighbors, k, facetT); if (!neighbor || neighbor == qh_DUPLICATEridge) count++; } if (facet == newfacet) break; } if (count != hashcount) { qh_fprintf(qh ferr, 6266, "qhull error (qh_matchnewfacets): after adding facet %d, hashcount %d != count %d\n", newfacet->id, hashcount, count); qh_errexit(qh_ERRdebug, newfacet, NULL); } } #endif /* end of trap code */ } /* end FORALLnew_facets */ if (hashcount) { /* all neighbors matched, except for qh_DUPLICATEridge neighbors */ qh_joggle_restart("ridge with multiple neighbors"); if (hashcount) { FORALLnew_facets { if (newfacet->dupridge) { FOREACHneighbor_i_(newfacet) { if (neighbor == qh_DUPLICATEridge) { maxdist2= qh_matchdupridge(newfacet, neighbor_i, hashsize, &hashcount); maximize_(maxdupdist, maxdist2); } } } } } } if (hashcount) { qh_fprintf(qh ferr, 6108, "qhull internal error (qh_matchnewfacets): %d neighbors did not match up\n", hashcount); qh_printhashtable(qh ferr); qh_errexit(qh_ERRqhull, NULL, NULL); } #ifndef qh_NOtrace if (qh IStracing >= 3) { FOREACHfacet_i_(qh hash_table) { if (!facet) numunused++; } qh_fprintf(qh ferr, 3063, "qh_matchnewfacets: maxdupdist %2.2g, new facets %d, unused hash entries %d, hashsize %d\n", maxdupdist, numnew, numunused, qh_setsize(qh hash_table)); } #endif /* !qh_NOtrace */ qh_setfree(&qh hash_table); if (qh PREmerge || qh MERGEexact) { if (qh IStracing >= 4) qh_printfacetlist(qh newfacet_list, NULL, qh_ALL); } return maxdupdist; } /* matchnewfacets */ /*--------------------------------- qh_matchvertices( firstindex, verticesA, skipA, verticesB, skipB, same ) tests whether vertices match with a single skip starts match at firstindex since all new facets have a common vertex returns: true if matched vertices skip index for skipB sets same iff vertices have the same orientation notes: called by qh_matchneighbor and qh_matchdupridge assumes skipA is in A and both sets are the same size design: set up pointers scan both sets checking for a match test orientation */ boolT qh_matchvertices(int firstindex, setT *verticesA, int skipA, setT *verticesB, int *skipB, boolT *same) { vertexT **elemAp, **elemBp, **skipBp=NULL, **skipAp; elemAp= SETelemaddr_(verticesA, firstindex, vertexT); elemBp= SETelemaddr_(verticesB, firstindex, vertexT); skipAp= SETelemaddr_(verticesA, skipA, vertexT); do if (elemAp != skipAp) { while (*elemAp != *elemBp++) { if (skipBp) return False; skipBp= elemBp; /* one extra like FOREACH */ } }while (*(++elemAp)); if (!skipBp) skipBp= ++elemBp; *skipB= SETindex_(verticesB, skipB); /* i.e., skipBp - verticesB verticesA and verticesB are the same size, otherwise trace4 may segfault */ *same= !((skipA & 0x1) ^ (*skipB & 0x1)); /* result is 0 or 1 */ trace4((qh ferr, 4054, "qh_matchvertices: matched by skip %d(v%d) and skip %d(v%d) same? %d\n", skipA, (*skipAp)->id, *skipB, (*(skipBp-1))->id, *same)); return(True); } /* matchvertices */ /*--------------------------------- qh_newfacet( ) return a new facet returns: all fields initialized or cleared (NULL) preallocates neighbors set */ facetT *qh_newfacet(void) { facetT *facet; void **freelistp; /* used if !qh_NOmem by qh_memalloc_() */ qh_memalloc_((int)sizeof(facetT), freelistp, facet, facetT); memset((char *)facet, (size_t)0, sizeof(facetT)); if (qh facet_id == qh tracefacet_id) qh tracefacet= facet; facet->id= qh facet_id++; facet->neighbors= qh_setnew(qh hull_dim); #if !qh_COMPUTEfurthest facet->furthestdist= 0.0; #endif #if qh_MAXoutside if (qh FORCEoutput && qh APPROXhull) facet->maxoutside= qh MINoutside; else facet->maxoutside= qh DISTround; /* same value as test for QH7082 */ #endif facet->simplicial= True; facet->good= True; facet->newfacet= True; trace4((qh ferr, 4055, "qh_newfacet: created facet f%d\n", facet->id)); return(facet); } /* newfacet */ /*--------------------------------- qh_newridge() return a new ridge notes: caller sets qh.traceridge */ ridgeT *qh_newridge(void) { ridgeT *ridge; void **freelistp; /* used if !qh_NOmem by qh_memalloc_() */ qh_memalloc_((int)sizeof(ridgeT), freelistp, ridge, ridgeT); memset((char *)ridge, (size_t)0, sizeof(ridgeT)); zinc_(Ztotridges); if (qh ridge_id == UINT_MAX) { qh_fprintf(qh ferr, 7074, "qhull warning: more than 2^32 ridges. Qhull results are OK. Since the ridge ID wraps around to 0, two ridges may have the same identifier.\n"); } ridge->id= qh ridge_id++; trace4((qh ferr, 4056, "qh_newridge: created ridge r%d\n", ridge->id)); return(ridge); } /* newridge */ /*--------------------------------- qh_pointid( point ) return id for a point, returns qh_IDnone(-3) if null, qh_IDinterior(-2) if interior, or qh_IDunknown(-1) if not known alternative code if point is in qh.first_point... unsigned long id; id= ((unsigned long)point - (unsigned long)qh.first_point)/qh.normal_size; notes: Valid points are non-negative WARN64 -- id truncated to 32-bits, at most 2G points NOerrors returned (QhullPoint::id) if point not in point array the code does a comparison of unrelated pointers. */ int qh_pointid(pointT *point) { ptr_intT offset, id; if (!point) return qh_IDnone; else if (point == qh interior_point) return qh_IDinterior; else if (point >= qh first_point && point < qh first_point + qh num_points * qh hull_dim) { offset= (ptr_intT)(point - qh first_point); id= offset / qh hull_dim; }else if ((id= qh_setindex(qh other_points, point)) != -1) id += qh num_points; else return qh_IDunknown; return (int)id; } /* pointid */ /*--------------------------------- qh_removefacet( facet ) unlinks facet from qh.facet_list, returns: updates qh.facet_list .newfacet_list .facet_next visible_list decrements qh.num_facets see: qh_appendfacet */ void qh_removefacet(facetT *facet) { facetT *next= facet->next, *previous= facet->previous; /* next is always defined */ if (facet == qh newfacet_list) qh newfacet_list= next; if (facet == qh facet_next) qh facet_next= next; if (facet == qh visible_list) qh visible_list= next; if (previous) { previous->next= next; next->previous= previous; }else { /* 1st facet in qh facet_list */ qh facet_list= next; qh facet_list->previous= NULL; } qh num_facets--; trace4((qh ferr, 4057, "qh_removefacet: removed f%d from facet_list, newfacet_list, and visible_list\n", facet->id)); } /* removefacet */ /*--------------------------------- qh_removevertex( vertex ) unlinks vertex from qh.vertex_list, returns: updates qh.vertex_list .newvertex_list decrements qh.num_vertices */ void qh_removevertex(vertexT *vertex) { vertexT *next= vertex->next, *previous= vertex->previous; /* next is always defined */ trace4((qh ferr, 4058, "qh_removevertex: remove v%d from qh.vertex_list\n", vertex->id)); if (vertex == qh newvertex_list) qh newvertex_list= next; if (previous) { previous->next= next; next->previous= previous; }else { /* 1st vertex in qh vertex_list */ qh vertex_list= next; qh vertex_list->previous= NULL; } qh num_vertices--; } /* removevertex */ /*--------------------------------- qh_update_vertexneighbors( ) update vertex neighbors and delete interior vertices returns: if qh.VERTEXneighbors, if qh.newvertex_list, removes visible neighbors from vertex neighbors if qh.newfacet_list adds new facets to vertex neighbors if qh.visible_list interior vertices added to qh.del_vertices for later partitioning as coplanar points if not qh.VERTEXneighbors (not merging) interior vertices of visible facets added to qh.del_vertices for later partitioning as coplanar points notes [jan'19] split off qh_update_vertexneighbors_cone. Optimize the remaining cases in a future release called by qh_triangulate_facet after triangulating a non-simplicial facet, followed by reset_lists called by qh_triangulate after triangulating null and mirror facets called by qh_all_vertexmerges after calling qh_merge_pinchedvertices design: if qh.VERTEXneighbors for each vertex on newvertex_list (i.e., new vertices and vertices of new facets) delete visible facets from vertex neighbors for each new facet on newfacet_list for each vertex of facet append facet to vertex neighbors for each visible facet on qh.visible_list for each vertex of facet if the vertex is not on a new facet and not itself deleted if the vertex has a not-visible neighbor (due to merging) remove the visible facet from the vertex's neighbors otherwise add the vertex to qh.del_vertices for later deletion if not qh.VERTEXneighbors (not merging) for each vertex of a visible facet if the vertex is not on a new facet and not itself deleted add the vertex to qh.del_vertices for later deletion */ void qh_update_vertexneighbors(void /* qh.newvertex_list, newfacet_list, visible_list */) { facetT *newfacet= NULL, *neighbor, **neighborp, *visible; vertexT *vertex, **vertexp; int neighborcount= 0; if (qh VERTEXneighbors) { trace3((qh ferr, 3013, "qh_update_vertexneighbors: update v.neighbors for qh.newvertex_list (v%d) and qh.newfacet_list (f%d)\n", getid_(qh newvertex_list), getid_(qh newfacet_list))); FORALLvertex_(qh newvertex_list) { neighborcount= 0; FOREACHneighbor_(vertex) { if (neighbor->visible) { neighborcount++; SETref_(neighbor)= NULL; } } if (neighborcount) { trace4((qh ferr, 4046, "qh_update_vertexneighbors: delete %d of %d vertex neighbors for v%d. Removes to-be-deleted, visible facets\n", neighborcount, qh_setsize(vertex->neighbors), vertex->id)); qh_setcompact(vertex->neighbors); } } FORALLnew_facets { if (qh first_newfacet && newfacet->id >= qh first_newfacet) { FOREACHvertex_(newfacet->vertices) qh_setappend(&vertex->neighbors, newfacet); }else { /* called after qh_merge_pinchedvertices. In 7-D, many more neighbors than new facets. qh_setin is expensive */ FOREACHvertex_(newfacet->vertices) qh_setunique(&vertex->neighbors, newfacet); } } trace3((qh ferr, 3058, "qh_update_vertexneighbors: delete interior vertices for qh.visible_list (f%d)\n", getid_(qh visible_list))); FORALLvisible_facets { FOREACHvertex_(visible->vertices) { if (!vertex->newfacet && !vertex->deleted) { FOREACHneighbor_(vertex) { /* this can happen under merging */ if (!neighbor->visible) break; } if (neighbor) qh_setdel(vertex->neighbors, visible); else { vertex->deleted= True; qh_setappend(&qh del_vertices, vertex); trace2((qh ferr, 2041, "qh_update_vertexneighbors: delete interior vertex p%d(v%d) of visible f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); } } } } }else { /* !VERTEXneighbors */ trace3((qh ferr, 3058, "qh_update_vertexneighbors: delete old vertices for qh.visible_list (f%d)\n", getid_(qh visible_list))); FORALLvisible_facets { FOREACHvertex_(visible->vertices) { if (!vertex->newfacet && !vertex->deleted) { vertex->deleted= True; qh_setappend(&qh del_vertices, vertex); trace2((qh ferr, 2042, "qh_update_vertexneighbors: will delete interior vertex p%d(v%d) of visible f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); } } } } } /* update_vertexneighbors */ /*--------------------------------- qh_update_vertexneighbors_cone( ) update vertex neighbors for a cone of new facets and delete interior vertices returns: if qh.VERTEXneighbors, if qh.newvertex_list, removes visible neighbors from vertex neighbors if qh.newfacet_list adds new facets to vertex neighbors if qh.visible_list interior vertices added to qh.del_vertices for later partitioning as coplanar points if not qh.VERTEXneighbors (not merging) interior vertices of visible facets added to qh.del_vertices for later partitioning as coplanar points notes called by qh_addpoint after create cone and before premerge design: if qh.VERTEXneighbors for each vertex on newvertex_list (i.e., new vertices and vertices of new facets) delete visible facets from vertex neighbors for each new facet on newfacet_list for each vertex of facet append facet to vertex neighbors for each visible facet on qh.visible_list for each vertex of facet if the vertex is not on a new facet and not itself deleted if the vertex has a not-visible neighbor (due to merging) remove the visible facet from the vertex's neighbors otherwise add the vertex to qh.del_vertices for later deletion if not qh.VERTEXneighbors (not merging) for each vertex of a visible facet if the vertex is not on a new facet and not itself deleted add the vertex to qh.del_vertices for later deletion */ void qh_update_vertexneighbors_cone(void /* qh.newvertex_list, newfacet_list, visible_list */) { facetT *newfacet= NULL, *neighbor, **neighborp, *visible; vertexT *vertex, **vertexp; int delcount= 0; if (qh VERTEXneighbors) { trace3((qh ferr, 3059, "qh_update_vertexneighbors_cone: update v.neighbors for qh.newvertex_list (v%d) and qh.newfacet_list (f%d)\n", getid_(qh newvertex_list), getid_(qh newfacet_list))); FORALLvertex_(qh newvertex_list) { delcount= 0; FOREACHneighbor_(vertex) { if (neighbor->visible) { /* alternative design is a loop over visible facets, but needs qh_setdel() */ delcount++; qh_setdelnth(vertex->neighbors, SETindex_(vertex->neighbors, neighbor)); neighborp--; /* repeat */ } } if (delcount) { trace4((qh ferr, 4021, "qh_update_vertexneighbors_cone: deleted %d visible vertexneighbors of v%d\n", delcount, vertex->id)); } } FORALLnew_facets { FOREACHvertex_(newfacet->vertices) qh_setappend(&vertex->neighbors, newfacet); } trace3((qh ferr, 3065, "qh_update_vertexneighbors_cone: delete interior vertices, if any, for qh.visible_list (f%d)\n", getid_(qh visible_list))); FORALLvisible_facets { FOREACHvertex_(visible->vertices) { if (!vertex->newfacet && !vertex->deleted) { FOREACHneighbor_(vertex) { /* this can happen under merging, qh_checkfacet QH4025 */ if (!neighbor->visible) break; } if (neighbor) qh_setdel(vertex->neighbors, visible); else { vertex->deleted= True; qh_setappend(&qh del_vertices, vertex); trace2((qh ferr, 2102, "qh_update_vertexneighbors_cone: will delete interior vertex p%d(v%d) of visible f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); } } } } }else { /* !VERTEXneighbors */ trace3((qh ferr, 3066, "qh_update_vertexneighbors_cone: delete interior vertices for qh.visible_list (f%d)\n", getid_(qh visible_list))); FORALLvisible_facets { FOREACHvertex_(visible->vertices) { if (!vertex->newfacet && !vertex->deleted) { vertex->deleted= True; qh_setappend(&qh del_vertices, vertex); trace2((qh ferr, 2059, "qh_update_vertexneighbors_cone: will delete interior vertex p%d(v%d) of visible f%d\n", qh_pointid(vertex->point), vertex->id, visible->id)); } } } } } /* update_vertexneighbors_cone */