xref: /petsc/src/dm/impls/moab/dmmbutil.cxx (revision 5b6bfdb9644f185dbf5e5a09b808ec241507e1e7)
1 #include <petsc/private/dmmbimpl.h> /*I  "petscdmmoab.h"   I*/
2 #include <petsc/private/vecimpl.h>
3 
4 #include <petscdmmoab.h>
5 #include <MBTagConventions.hpp>
6 #include <moab/ReadUtilIface.hpp>
7 #include <moab/MergeMesh.hpp>
8 #include <moab/CN.hpp>
9 
10 typedef struct {
11   // options
12   PetscInt  A, B, C, M, N, K, dim;
13   PetscInt  blockSizeVertexXYZ[3];              // Number of element blocks per partition
14   PetscInt  blockSizeElementXYZ[3];
15   PetscReal xyzbounds[6]; // the physical size of the domain
16   bool      newMergeMethod, keep_skins, simplex, adjEnts;
17 
18   // compute params
19   PetscReal dx, dy, dz;
20   PetscInt  NX, NY, NZ, nex, ney, nez;
21   PetscInt  q, xstride, ystride, zstride;
22   PetscBool usrxyzgrid, usrprocgrid, usrrefgrid;
23   PetscInt  fraction, remainder, cumfraction;
24   PetscLogEvent generateMesh, generateElements, generateVertices, parResolve;
25 
26 } DMMoabMeshGeneratorCtx;
27 
28 
29 PetscInt DMMoab_SetTensorElementConnectivity_Private(DMMoabMeshGeneratorCtx& genCtx, PetscInt offset, PetscInt corner, std::vector<PetscInt>& subent_conn, moab::EntityHandle *connectivity)
30 {
31   switch (genCtx.dim) {
32   case 1:
33     subent_conn.resize(2);
34     moab::CN::SubEntityVertexIndices(moab::MBEDGE, 1, 0, subent_conn.data());
35     connectivity[offset + subent_conn[0]] = corner;
36     connectivity[offset + subent_conn[1]] = corner + 1;
37     break;
38   case 2:
39     subent_conn.resize(4);
40     moab::CN::SubEntityVertexIndices(moab::MBQUAD, 2, 0, subent_conn.data());
41     connectivity[offset + subent_conn[0]] = corner;
42     connectivity[offset + subent_conn[1]] = corner + 1;
43     connectivity[offset + subent_conn[2]] = corner + 1 + genCtx.ystride;
44     connectivity[offset + subent_conn[3]] = corner + genCtx.ystride;
45     break;
46   case 3:
47   default:
48     subent_conn.resize(8);
49     moab::CN::SubEntityVertexIndices(moab::MBHEX, 3, 0, subent_conn.data());
50     connectivity[offset + subent_conn[0]] = corner;
51     connectivity[offset + subent_conn[1]] = corner + 1;
52     connectivity[offset + subent_conn[2]] = corner + 1 + genCtx.ystride;
53     connectivity[offset + subent_conn[3]] = corner + genCtx.ystride;
54     connectivity[offset + subent_conn[4]] = corner + genCtx.zstride;
55     connectivity[offset + subent_conn[5]] = corner + 1 + genCtx.zstride;
56     connectivity[offset + subent_conn[6]] = corner + 1 + genCtx.ystride + genCtx.zstride;
57     connectivity[offset + subent_conn[7]] = corner + genCtx.ystride + genCtx.zstride;
58     break;
59   }
60   return subent_conn.size();
61 }
62 
63 
64 PetscInt DMMoab_SetSimplexElementConnectivity_Private(DMMoabMeshGeneratorCtx& genCtx, PetscInt subelem, PetscInt offset, PetscInt corner, std::vector<PetscInt>& subent_conn, moab::EntityHandle *connectivity)
65 {
66   PetscInt A, B, C, D, E, F, G, H, M;
67   const PetscInt trigen_opts = 1; /* 1 - Aligned diagonally to right, 2 - Aligned diagonally to left, 3 - 4 elements per quad */
68   A = corner;
69   B = corner + 1;
70   switch (genCtx.dim) {
71   case 1:
72     subent_conn.resize(2);  /* only linear EDGE supported now */
73     moab::CN::SubEntityVertexIndices(moab::MBEDGE, 1, 0, subent_conn.data());
74     connectivity[offset + subent_conn[0]] = A;
75     connectivity[offset + subent_conn[1]] = B;
76     break;
77   case 2:
78     C = corner + 1 + genCtx.ystride;
79     D = corner +     genCtx.ystride;
80     M = corner + 0.5; /* technically -- need to modify vertex generation */
81     subent_conn.resize(3);  /* only linear TRI supported */
82     moab::CN::SubEntityVertexIndices(moab::MBTRI, 2, 0, subent_conn.data());
83     if (trigen_opts == 1) {
84       if (subelem) { /* 0 1 2 of a QUAD */
85         connectivity[offset + subent_conn[0]] = B;
86         connectivity[offset + subent_conn[1]] = C;
87         connectivity[offset + subent_conn[2]] = A;
88       }
89       else {        /* 2 3 0 of a QUAD */
90         connectivity[offset + subent_conn[0]] = D;
91         connectivity[offset + subent_conn[1]] = A;
92         connectivity[offset + subent_conn[2]] = C;
93       }
94     }
95     else if (trigen_opts == 2) {
96       if (subelem) { /* 0 1 2 of a QUAD */
97         connectivity[offset + subent_conn[0]] = A;
98         connectivity[offset + subent_conn[1]] = B;
99         connectivity[offset + subent_conn[2]] = D;
100       }
101       else {        /* 2 3 0 of a QUAD */
102         connectivity[offset + subent_conn[0]] = C;
103         connectivity[offset + subent_conn[1]] = D;
104         connectivity[offset + subent_conn[2]] = B;
105       }
106     }
107     else {
108       switch (subelem) { /* 0 1 2 of a QUAD */
109       case 0:
110         connectivity[offset + subent_conn[0]] = A;
111         connectivity[offset + subent_conn[1]] = B;
112         connectivity[offset + subent_conn[2]] = M;
113         break;
114       case 1:
115         connectivity[offset + subent_conn[0]] = B;
116         connectivity[offset + subent_conn[1]] = C;
117         connectivity[offset + subent_conn[2]] = M;
118         break;
119       case 2:
120         connectivity[offset + subent_conn[0]] = C;
121         connectivity[offset + subent_conn[1]] = D;
122         connectivity[offset + subent_conn[2]] = M;
123         break;
124       case 3:
125         connectivity[offset + subent_conn[0]] = D;
126         connectivity[offset + subent_conn[1]] = A;
127         connectivity[offset + subent_conn[2]] = M;
128         break;
129       }
130     }
131     break;
132   case 3:
133   default:
134     C = corner + 1 + genCtx.ystride;
135     D = corner +     genCtx.ystride;
136     E = corner +                      genCtx.zstride;
137     F = corner + 1 +                  genCtx.zstride;
138     G = corner + 1 + genCtx.ystride + genCtx.zstride;
139     H = corner +     genCtx.ystride + genCtx.zstride;
140     subent_conn.resize(4);  /* only linear TET supported */
141     moab::CN::SubEntityVertexIndices(moab::MBTET, 3, 0, subent_conn.data());
142     switch (subelem) {
143     case 0: /* 4 3 7 6 of a HEX */
144       connectivity[offset + subent_conn[0]] = E;
145       connectivity[offset + subent_conn[1]] = D;
146       connectivity[offset + subent_conn[2]] = H;
147       connectivity[offset + subent_conn[3]] = G;
148       break;
149     case 1: /* 0 1 2 5 of a HEX */
150       connectivity[offset + subent_conn[0]] = A;
151       connectivity[offset + subent_conn[1]] = B;
152       connectivity[offset + subent_conn[2]] = C;
153       connectivity[offset + subent_conn[3]] = F;
154       break;
155     case 2: /* 0 3 4 5 of a HEX */
156       connectivity[offset + subent_conn[0]] = A;
157       connectivity[offset + subent_conn[1]] = D;
158       connectivity[offset + subent_conn[2]] = E;
159       connectivity[offset + subent_conn[3]] = F;
160       break;
161     case 3: /* 2 6 3 5 of a HEX */
162       connectivity[offset + subent_conn[0]] = C;
163       connectivity[offset + subent_conn[1]] = G;
164       connectivity[offset + subent_conn[2]] = D;
165       connectivity[offset + subent_conn[3]] = F;
166       break;
167     case 4: /* 0 2 3 5 of a HEX */
168       connectivity[offset + subent_conn[0]] = A;
169       connectivity[offset + subent_conn[1]] = C;
170       connectivity[offset + subent_conn[2]] = D;
171       connectivity[offset + subent_conn[3]] = F;
172       break;
173     case 5: /* 3 6 4 5 of a HEX */
174       connectivity[offset + subent_conn[0]] = D;
175       connectivity[offset + subent_conn[1]] = G;
176       connectivity[offset + subent_conn[2]] = E;
177       connectivity[offset + subent_conn[3]] = F;
178       break;
179     }
180     break;
181   }
182   return subent_conn.size();
183 }
184 
185 
186 std::pair<PetscInt, PetscInt> DMMoab_SetElementConnectivity_Private(DMMoabMeshGeneratorCtx& genCtx, PetscInt offset, PetscInt corner, moab::EntityHandle *connectivity)
187 {
188   PetscInt vcount = 0;
189   PetscInt simplices_per_tensor[4] = {0, 1, 2, 6};
190   std::vector<PetscInt> subent_conn;  /* only linear edge, tri, tet supported now */
191   subent_conn.reserve(27);
192   PetscInt m, subelem;
193   if (genCtx.simplex) {
194     subelem = simplices_per_tensor[genCtx.dim];
195     for (m = 0; m < subelem; m++) {
196       vcount = DMMoab_SetSimplexElementConnectivity_Private(genCtx, m, offset, corner, subent_conn, connectivity);
197       offset += vcount;
198     }
199   }
200   else {
201     subelem = 1;
202     vcount = DMMoab_SetTensorElementConnectivity_Private(genCtx, offset, corner, subent_conn, connectivity);
203   }
204   return std::pair<PetscInt, PetscInt>(vcount * subelem, subelem);
205 }
206 
207 
208 PetscErrorCode DMMoab_GenerateVertices_Private(moab::Interface *mbImpl, moab::ReadUtilIface *iface, DMMoabMeshGeneratorCtx& genCtx, PetscInt m, PetscInt n, PetscInt k,
209     PetscInt a, PetscInt b, PetscInt c, moab::Tag& global_id_tag, moab::EntityHandle& startv, moab::Range& uverts)
210 {
211   PetscInt x, y, z, ix, nnodes;
212   PetscErrorCode ierr;
213   PetscInt ii, jj, kk;
214   std::vector<PetscReal*> arrays;
215   PetscInt* gids;
216   moab::ErrorCode merr;
217 
218   PetscFunctionBegin;
219   /* we will generate (q*block+1)^3 vertices, and block^3 hexas; q is 1 for linear, 2 for quadratic
220    * the global id of the vertices will come from m, n, k, a, b, c
221    * x will vary from  m*A*q*block + a*q*block to m*A*q*block+(a+1)*q*block etc.
222    */
223   nnodes = genCtx.blockSizeVertexXYZ[0] * (genCtx.dim > 1 ? genCtx.blockSizeVertexXYZ[1] * (genCtx.dim > 2 ? genCtx.blockSizeVertexXYZ[2] : 1) : 1);
224   ierr = PetscMalloc1(nnodes, &gids);CHKERRQ(ierr);
225 
226   merr = iface->get_node_coords(3, nnodes, 0, startv, arrays);MBERR("Can't get node coords.", merr);
227 
228   /* will start with the lower corner: */
229   /* x = ( m * genCtx.A + a ) * genCtx.q * genCtx.blockSizeElementXYZ[0]; */
230   /* y = ( n * genCtx.B + b ) * genCtx.q * genCtx.blockSizeElementXYZ[1]; */
231   /* z = ( k * genCtx.C + c ) * genCtx.q * genCtx.blockSizeElementXYZ[2]; */
232 
233   x = ( m * genCtx.A + a ) * genCtx.q;
234   y = ( n * genCtx.B + b ) * genCtx.q;
235   z = ( k * genCtx.C + c ) * genCtx.q;
236   PetscInfo3(NULL, "Starting offset for coordinates := %d, %d, %d\n", x, y, z);
237   ix = 0;
238   moab::Range verts(startv, startv + nnodes - 1);
239   for (kk = 0; kk < (genCtx.dim > 2 ? genCtx.blockSizeVertexXYZ[2] : 1); kk++) {
240     for (jj = 0; jj < (genCtx.dim > 1 ? genCtx.blockSizeVertexXYZ[1] : 1); jj++) {
241       for (ii = 0; ii < genCtx.blockSizeVertexXYZ[0]; ii++, ix++) {
242         /* set coordinates for the vertices */
243         arrays[0][ix] = (x + ii) * genCtx.dx + genCtx.xyzbounds[0];
244         arrays[1][ix] = (y + jj) * genCtx.dy + genCtx.xyzbounds[2];
245         arrays[2][ix] = (z + kk) * genCtx.dz + genCtx.xyzbounds[4];
246         PetscInfo3(NULL, "Creating vertex with coordinates := %f, %f, %f\n", arrays[0][ix], arrays[1][ix], arrays[2][ix]);
247 
248         /* If we want to set some tags on the vertices -> use the following entity handle definition:
249            moab::EntityHandle v = startv + ix;
250         */
251         /* compute the global ID for vertex */
252         gids[ix] = 1 + (x + ii) + (y + jj) * genCtx.NX + (z + kk) * (genCtx.NX * genCtx.NY);
253       }
254     }
255   }
256   /* set global ID data on vertices */
257   mbImpl->tag_set_data(global_id_tag, verts, &gids[0]);
258   verts.swap(uverts);
259   ierr = PetscFree(gids);CHKERRQ(ierr);
260   PetscFunctionReturn(0);
261 }
262 
263 PetscErrorCode DMMoab_GenerateElements_Private(moab::Interface* mbImpl, moab::ReadUtilIface* iface, DMMoabMeshGeneratorCtx& genCtx, PetscInt m, PetscInt n, PetscInt k,
264     PetscInt a, PetscInt b, PetscInt c, moab::Tag& global_id_tag, moab::EntityHandle startv, moab::Range& cells)
265 {
266   moab::ErrorCode merr;
267   PetscInt ix, ie, xe, ye, ze;
268   PetscInt ii, jj, kk, nvperelem;
269   PetscInt simplices_per_tensor[4] = {0, 1, 2, 6};
270   PetscInt ntensorelems = genCtx.blockSizeElementXYZ[0] * (genCtx.dim > 1 ? genCtx.blockSizeElementXYZ[1] * (genCtx.dim > 2 ? genCtx.blockSizeElementXYZ[2] : 1) : 1); /*pow(genCtx.blockSizeElement,genCtx.dim);*/
271   PetscInt nelems = ntensorelems;
272   moab::EntityHandle starte; /* connectivity */
273   moab::EntityHandle* conn;
274 
275   PetscFunctionBegin;
276   switch (genCtx.dim) {
277   case 1:
278     nvperelem = 2;
279     merr = iface->get_element_connect(nelems, 2, moab::MBEDGE, 0, starte, conn);MBERR("Can't get EDGE2 element connectivity.", merr);
280     break;
281   case 2:
282     if (genCtx.simplex) {
283       nvperelem = 3;
284       nelems = ntensorelems * simplices_per_tensor[genCtx.dim];
285       merr = iface->get_element_connect(nelems, 3, moab::MBTRI, 0, starte, conn);MBERR("Can't get TRI3 element connectivity.", merr);
286     }
287     else {
288       nvperelem = 4;
289       merr = iface->get_element_connect(nelems, 4, moab::MBQUAD, 0, starte, conn);MBERR("Can't get QUAD4 element connectivity.", merr);
290     }
291     break;
292   case 3:
293   default:
294     if (genCtx.simplex) {
295       nvperelem = 4;
296       nelems = ntensorelems * simplices_per_tensor[genCtx.dim];
297       merr = iface->get_element_connect(nelems, 4, moab::MBTET, 0, starte, conn);MBERR("Can't get TET4 element connectivity.", merr);
298     }
299     else {
300       nvperelem = 8;
301       merr = iface->get_element_connect(nelems, 8, moab::MBHEX, 0, starte, conn);MBERR("Can't get HEX8 element connectivity.", merr);
302     }
303     break;
304   }
305 
306   ix = ie = 0; /* index now in the elements, for global ids */
307 
308   /* create a temporary range to store local element handles */
309   moab::Range tmp(starte, starte + nelems - 1);
310   std::vector<PetscInt> gids(nelems);
311 
312   /* identify the elements at the lower corner, for their global ids */
313   xe = m * genCtx.A * genCtx.blockSizeElementXYZ[0] + a * genCtx.blockSizeElementXYZ[0];
314   ye = (genCtx.dim > 1 ? n * genCtx.B * genCtx.blockSizeElementXYZ[1] + b * genCtx.blockSizeElementXYZ[1] : 0);
315   ze = (genCtx.dim > 2 ? k * genCtx.C * genCtx.blockSizeElementXYZ[2] + c * genCtx.blockSizeElementXYZ[2] : 0);
316 
317   /* create owned elements requested by genCtx */
318   for (kk = 0; kk < (genCtx.dim > 2 ? genCtx.blockSizeElementXYZ[2] : 1); kk++) {
319     for (jj = 0; jj < (genCtx.dim > 1 ? genCtx.blockSizeElementXYZ[1] : 1); jj++) {
320       for (ii = 0; ii < genCtx.blockSizeElementXYZ[0]; ii++) {
321 
322         moab::EntityHandle corner = startv + genCtx.q * ii + genCtx.q * jj * genCtx.ystride + genCtx.q * kk * genCtx.zstride;
323 
324         std::pair<PetscInt, PetscInt> entoffset = DMMoab_SetElementConnectivity_Private(genCtx, ix, corner, conn);
325 
326         for (PetscInt j = 0; j < entoffset.second; j++) {
327           /* The entity handle for the particular element -> if we want to set some tags is
328              moab::EntityHandle eh = starte + ie + j;
329           */
330           gids[ie + j] = 1 + ((xe + ii) + (ye + jj) * genCtx.nex + (ze + kk) * (genCtx.nex * genCtx.ney));
331           /* gids[ie+j] = ie + j + ((xe + ii) + (ye + jj) * genCtx.nex + (ze + kk) * (genCtx.nex * genCtx.ney)); */
332           /* gids[ie+j] = 1 + ie; */
333           /* ie++; */
334         }
335 
336         ix += entoffset.first;
337         ie += entoffset.second;
338       }
339     }
340   }
341   if (genCtx.adjEnts) { /* we need to update adjacencies now, because some elements are new */
342     merr = iface->update_adjacencies(starte, nelems, nvperelem, conn);MBERR("Can't update adjacencies", merr);
343   }
344   tmp.swap(cells);
345   merr = mbImpl->tag_set_data(global_id_tag, cells, &gids[0]);MBERR("Can't set global ids to elements.", merr);
346   PetscFunctionReturn(0);
347 }
348 
349 PetscErrorCode DMMBUtil_InitializeOptions(DMMoabMeshGeneratorCtx& genCtx, PetscInt dim, PetscBool simplex, PetscInt rank, PetscInt nprocs, const PetscReal* bounds, PetscInt nelems)
350 {
351   PetscFunctionBegin;
352   /* Initialize all genCtx data */
353   genCtx.dim = dim;
354   genCtx.simplex = simplex;
355   genCtx.newMergeMethod = genCtx.keep_skins = genCtx.adjEnts = true;
356   /* determine other global quantities for the mesh used for nodes increments */
357   genCtx.q = 1;
358   genCtx.fraction = genCtx.remainder = genCtx.cumfraction = 0;
359 
360   if (!genCtx.usrxyzgrid) { /* not overridden by genCtx - assume nele equally and that genCtx wants a uniform cube mesh */
361 
362     genCtx.fraction = nelems / nprocs; /* partition only by the largest dimension */
363     genCtx.remainder = nelems % nprocs; /* remainder after partition which gets evenly distributed by round-robin */
364     genCtx.cumfraction = (rank > 0 ? (genCtx.fraction) * (rank) + (rank - 1 < genCtx.remainder ? rank : genCtx.remainder ) : 0);
365     if (rank < genCtx.remainder)    /* This process gets "fraction+1" elements */
366       genCtx.fraction++;
367 
368     PetscInfo3(NULL, "Fraction = %D, Remainder = %D, Cumulative fraction = %D\n", genCtx.fraction, genCtx.remainder, genCtx.cumfraction);
369     switch (genCtx.dim) {
370     case 1:
371       genCtx.blockSizeElementXYZ[0] = genCtx.fraction;
372       genCtx.blockSizeElementXYZ[1] = 1;
373       genCtx.blockSizeElementXYZ[2] = 1;
374       break;
375     case 2:
376       genCtx.blockSizeElementXYZ[0] = nelems;
377       genCtx.blockSizeElementXYZ[1] = genCtx.fraction;
378       genCtx.blockSizeElementXYZ[2] = 1;
379       break;
380     case 3:
381     default:
382       genCtx.blockSizeElementXYZ[0] = nelems;
383       genCtx.blockSizeElementXYZ[1] = nelems;
384       genCtx.blockSizeElementXYZ[2] = genCtx.fraction;
385       break;
386     }
387   }
388 
389   /* partition only by the largest dimension */
390   /* Total number of local elements := genCtx.blockSizeElementXYZ[0]*(genCtx.dim>1? genCtx.blockSizeElementXYZ[1]*(genCtx.dim>2 ? genCtx.blockSizeElementXYZ[2]:1) :1); */
391   if (bounds) {
392     for (PetscInt i = 0; i < 6; i++)
393       genCtx.xyzbounds[i] = bounds[i];
394   }
395   else {
396     genCtx.xyzbounds[0] = genCtx.xyzbounds[2] = genCtx.xyzbounds[4] = 0.0;
397     genCtx.xyzbounds[1] = genCtx.xyzbounds[3] = genCtx.xyzbounds[5] = 1.0;
398   }
399 
400   if (!genCtx.usrprocgrid) {
401     switch (genCtx.dim) {
402     case 1:
403       genCtx.M = nprocs;
404       genCtx.N = genCtx.K = 1;
405       break;
406     case 2:
407       genCtx.N = nprocs;
408       genCtx.M = genCtx.K = 1;
409       break;
410     default:
411       genCtx.K = nprocs;
412       genCtx.M = genCtx.N = 1;
413       break;
414     }
415   }
416 
417   if (!genCtx.usrrefgrid) {
418     genCtx.A = genCtx.B = genCtx.C = 1;
419   }
420 
421   /* more default values */
422   genCtx.nex = genCtx.ney = genCtx.nez = 0;
423   genCtx.xstride = genCtx.ystride = genCtx.zstride = 0;
424   genCtx.NX = genCtx.NY = genCtx.NZ = 0;
425   genCtx.nex = genCtx.ney = genCtx.nez = 0;
426   genCtx.blockSizeVertexXYZ[0] = genCtx.blockSizeVertexXYZ[1] = genCtx.blockSizeVertexXYZ[2] = 1;
427 
428   switch (genCtx.dim) {
429   case 3:
430     genCtx.blockSizeVertexXYZ[0] = genCtx.q * genCtx.blockSizeElementXYZ[0] + 1;
431     genCtx.blockSizeVertexXYZ[1] = genCtx.q * genCtx.blockSizeElementXYZ[1] + 1;
432     genCtx.blockSizeVertexXYZ[2] = genCtx.q * genCtx.blockSizeElementXYZ[2] + 1;
433 
434     genCtx.nex = genCtx.M * genCtx.A * genCtx.blockSizeElementXYZ[0];   /* number of elements in x direction, used for global id on element */
435     genCtx.dx = (genCtx.xyzbounds[1] - genCtx.xyzbounds[0]) / (nelems * genCtx.q); /* distance between 2 nodes in x direction */
436     genCtx.NX = (genCtx.q * genCtx.nex + 1);
437     genCtx.xstride = 1;
438     genCtx.ney = genCtx.N * genCtx.B * genCtx.blockSizeElementXYZ[1];  /* number of elements in y direction  .... */
439     genCtx.dy = (genCtx.xyzbounds[3] - genCtx.xyzbounds[2]) / (nelems * genCtx.q); /* distance between 2 nodes in y direction */
440     genCtx.NY = (genCtx.q * genCtx.ney + 1);
441     genCtx.ystride = genCtx.blockSizeVertexXYZ[0];
442     genCtx.nez = genCtx.K * genCtx.C * genCtx.blockSizeElementXYZ[2];  /* number of elements in z direction  .... */
443     genCtx.dz = (genCtx.xyzbounds[5] - genCtx.xyzbounds[4]) / (nelems * genCtx.q); /* distance between 2 nodes in z direction */
444     genCtx.NZ = (genCtx.q * genCtx.nez + 1);
445     genCtx.zstride = genCtx.blockSizeVertexXYZ[0] * genCtx.blockSizeVertexXYZ[1];
446     break;
447   case 2:
448     genCtx.blockSizeVertexXYZ[0] = genCtx.q * genCtx.blockSizeElementXYZ[0] + 1;
449     genCtx.blockSizeVertexXYZ[1] = genCtx.q * genCtx.blockSizeElementXYZ[1] + 1;
450     genCtx.blockSizeVertexXYZ[2] = 0;
451 
452     genCtx.nex = genCtx.M * genCtx.A * genCtx.blockSizeElementXYZ[0];   /* number of elements in x direction, used for global id on element */
453     genCtx.dx = (genCtx.xyzbounds[1] - genCtx.xyzbounds[0]) / (genCtx.nex * genCtx.q); /* distance between 2 nodes in x direction */
454     genCtx.NX = (genCtx.q * genCtx.nex + 1);
455     genCtx.xstride = 1;
456     genCtx.ney = genCtx.N * genCtx.B * genCtx.blockSizeElementXYZ[1];  /* number of elements in y direction  .... */
457     genCtx.dy = (genCtx.xyzbounds[3] - genCtx.xyzbounds[2]) / (nelems * genCtx.q); /* distance between 2 nodes in y direction */
458     genCtx.NY = (genCtx.q * genCtx.ney + 1);
459     genCtx.ystride = genCtx.blockSizeVertexXYZ[0];
460     break;
461   case 1:
462     genCtx.blockSizeVertexXYZ[1] = genCtx.blockSizeVertexXYZ[2] = 0;
463     genCtx.blockSizeVertexXYZ[0] = genCtx.q * genCtx.blockSizeElementXYZ[0] + 1;
464 
465     genCtx.nex = genCtx.M * genCtx.A * genCtx.blockSizeElementXYZ[0];   /* number of elements in x direction, used for global id on element */
466     genCtx.dx = (genCtx.xyzbounds[1] - genCtx.xyzbounds[0]) / (nelems * genCtx.q); /* distance between 2 nodes in x direction */
467     genCtx.NX = (genCtx.q * genCtx.nex + 1);
468     genCtx.xstride = 1;
469     break;
470   }
471 
472   /* Lets check for some valid input */
473   if (genCtx.dim < 1 || genCtx.dim > 3) SETERRQ1(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Invalid topological dimension specified: %d.\n", genCtx.dim);
474   if (genCtx.M * genCtx.N * genCtx.K != nprocs) SETERRQ4(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Invalid [m, n, k] data: %d, %d, %d. Product must be equal to global size = %d.\n", genCtx.M, genCtx.N, genCtx.K, nprocs);
475   /* validate the bounds data */
476   if (genCtx.xyzbounds[0] >= genCtx.xyzbounds[1]) SETERRQ2(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "X-dim: Left boundary cannot be greater than right. [%G >= %G]\n", genCtx.xyzbounds[0], genCtx.xyzbounds[1]);
477   if (genCtx.dim > 1 && (genCtx.xyzbounds[2] >= genCtx.xyzbounds[3])) SETERRQ2(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Y-dim: Left boundary cannot be greater than right. [%G >= %G]\n", genCtx.xyzbounds[2], genCtx.xyzbounds[3]);
478   if (genCtx.dim > 2 && (genCtx.xyzbounds[4] >= genCtx.xyzbounds[5])) SETERRQ2(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Z-dim: Left boundary cannot be greater than right. [%G >= %G]\n", genCtx.xyzbounds[4], genCtx.xyzbounds[5]);
479 
480   PetscInfo3(NULL, "Local elements:= %d, %d, %d\n", genCtx.blockSizeElementXYZ[0], genCtx.blockSizeElementXYZ[1], genCtx.blockSizeElementXYZ[2]);
481   PetscInfo3(NULL, "Local vertices:= %d, %d, %d\n", genCtx.blockSizeVertexXYZ[0], genCtx.blockSizeVertexXYZ[1], genCtx.blockSizeVertexXYZ[2]);
482   PetscInfo3(NULL, "Local blocks/processors := %d, %d, %d\n", genCtx.A, genCtx.B, genCtx.C);
483   PetscInfo3(NULL, "Local processors := %d, %d, %d\n", genCtx.M, genCtx.N, genCtx.K);
484   PetscInfo3(NULL, "Local nexyz:= %d, %d, %d\n", genCtx.nex, genCtx.ney, genCtx.nez);
485   PetscInfo3(NULL, "Local delxyz:= %g, %g, %g\n", genCtx.dx, genCtx.dy, genCtx.dz);
486   PetscInfo3(NULL, "Local strides:= %d, %d, %d\n", genCtx.xstride, genCtx.ystride, genCtx.zstride);
487   PetscFunctionReturn(0);
488 }
489 
490 /*@
491   DMMoabCreateBoxMesh - Creates a mesh on the tensor product (box) of intervals with genCtx specified bounds.
492 
493   Collective on MPI_Comm
494 
495   Input Parameters:
496 + comm - The communicator for the DM object
497 . dim - The spatial dimension
498 . bounds - The bounds of the box specified with [x-left, x-right, y-bottom, y-top, z-bottom, z-top] depending on the spatial dimension
499 . nele - The number of discrete elements in each direction
500 . user_nghost - The number of ghosted layers needed in the partitioned mesh
501 
502   Output Parameter:
503 . dm  - The DM object
504 
505   Level: beginner
506 
507 .keywords: DM, create
508 .seealso: DMSetType(), DMCreate(), DMMoabLoadFromFile()
509 @*/
510 PetscErrorCode DMMoabCreateBoxMesh(MPI_Comm comm, PetscInt dim, PetscBool useSimplex, const PetscReal* bounds, PetscInt nele, PetscInt nghost, DM *dm)
511 {
512   PetscErrorCode         ierr;
513   moab::ErrorCode        merr;
514   PetscInt               a, b, c, n, global_size, global_rank;
515   DM_Moab               *dmmoab;
516   moab::Interface       *mbImpl;
517 #ifdef MOAB_HAVE_MPI
518   moab::ParallelComm    *pcomm;
519 #endif
520   moab::ReadUtilIface   *readMeshIface;
521   moab::Range            verts, cells, edges, faces, adj, dim3, dim2;
522   DMMoabMeshGeneratorCtx genCtx;
523   const PetscInt         npts = nele + 1;    /* Number of points in every dimension */
524 
525   moab::Tag              global_id_tag, part_tag, geom_tag, mat_tag, dir_tag, neu_tag;
526   moab::Range            ownedvtx, ownedelms, localvtxs, localelms;
527   moab::EntityHandle     regionset;
528   PetscInt               ml = 0, nl = 0, kl = 0;
529 
530   PetscFunctionBegin;
531   if (dim < 1 || dim > 3) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Invalid dimension argument for mesh: dim=[1,3].\n");
532 
533   ierr = PetscLogEventRegister("GenerateMesh", DM_CLASSID,   &genCtx.generateMesh);CHKERRQ(ierr);
534   ierr = PetscLogEventRegister("AddVertices", DM_CLASSID,   &genCtx.generateVertices);CHKERRQ(ierr);
535   ierr = PetscLogEventRegister("AddElements", DM_CLASSID,   &genCtx.generateElements);CHKERRQ(ierr);
536   ierr = PetscLogEventRegister("ParResolve", DM_CLASSID,   &genCtx.parResolve);CHKERRQ(ierr);
537   ierr = PetscLogEventBegin(genCtx.generateMesh, 0, 0, 0, 0);CHKERRQ(ierr);
538   ierr = MPI_Comm_size(comm, &global_size);CHKERRQ(ierr);
539   /* total number of vertices in all dimensions */
540   n = pow(npts, dim);
541 
542   /* do some error checking */
543   if (n < 2) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Number of points must be >= 2.\n");
544   if (global_size > n) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Number of processors must be less than or equal to number of elements.\n");
545   if (nghost < 0) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Number of ghost layers cannot be negative.\n");
546 
547   /* Create the basic DMMoab object and keep the default parameters created by DM impls */
548   ierr = DMMoabCreateMoab(comm, NULL, NULL, NULL, dm);CHKERRQ(ierr);
549 
550   /* get all the necessary handles from the private DM object */
551   dmmoab = (DM_Moab*)(*dm)->data;
552   mbImpl = dmmoab->mbiface;
553 #ifdef MOAB_HAVE_MPI
554   pcomm = dmmoab->pcomm;
555   global_rank = pcomm->rank();
556 #else
557   global_rank = 0;
558   global_size = 1;
559 #endif
560   global_id_tag = dmmoab->ltog_tag;
561   dmmoab->dim = dim;
562   dmmoab->nghostrings = nghost;
563   dmmoab->refct = 1;
564 
565   /* create a file set to associate all entities in current mesh */
566   merr = mbImpl->create_meshset(moab::MESHSET_SET, dmmoab->fileset);MBERR("Creating file set failed", merr);
567 
568   /* No errors yet; proceed with building the mesh */
569   merr = mbImpl->query_interface(readMeshIface);MBERRNM(merr);
570 
571   genCtx.M = genCtx.N = genCtx.K = 1;
572   genCtx.A = genCtx.B = genCtx.C = 1;
573 
574   ierr = PetscOptionsBegin(comm, "", "DMMoab Creation Options", "DMMOAB");CHKERRQ(ierr);
575   /* Handle DMMoab spatial resolution */
576   PetscOptionsInt("-dmb_grid_x", "Number of grid points in x direction", "DMMoabSetSizes", genCtx.blockSizeElementXYZ[0], &genCtx.blockSizeElementXYZ[0], &genCtx.usrxyzgrid);
577   if (dim > 1) {PetscOptionsInt("-dmb_grid_y", "Number of grid points in y direction", "DMMoabSetSizes", genCtx.blockSizeElementXYZ[1], &genCtx.blockSizeElementXYZ[1], &genCtx.usrxyzgrid);}
578   if (dim > 2) {PetscOptionsInt("-dmb_grid_z", "Number of grid points in z direction", "DMMoabSetSizes", genCtx.blockSizeElementXYZ[2], &genCtx.blockSizeElementXYZ[2], &genCtx.usrxyzgrid);}
579 
580   /* Handle DMMoab parallel distibution */
581   PetscOptionsInt("-dmb_processors_x", "Number of processors in x direction", "DMMoabSetNumProcs", genCtx.M, &genCtx.M, &genCtx.usrprocgrid);
582   if (dim > 1) {PetscOptionsInt("-dmb_processors_y", "Number of processors in y direction", "DMMoabSetNumProcs", genCtx.N, &genCtx.N, &genCtx.usrprocgrid);}
583   if (dim > 2) {PetscOptionsInt("-dmb_processors_z", "Number of processors in z direction", "DMMoabSetNumProcs", genCtx.K, &genCtx.K, &genCtx.usrprocgrid);}
584 
585   /* Handle DMMoab block refinement */
586   PetscOptionsInt("-dmb_refine_x", "Number of refinement blocks in x direction", "DMMoabSetRefinement", genCtx.A, &genCtx.A, &genCtx.usrrefgrid);
587   if (dim > 1) {PetscOptionsInt("-dmb_refine_y", "Number of refinement blocks in y direction", "DMMoabSetRefinement", genCtx.B, &genCtx.B, &genCtx.usrrefgrid);}
588   if (dim > 2) {PetscOptionsInt("-dmb_refine_z", "Number of refinement blocks in z direction", "DMMoabSetRefinement", genCtx.C, &genCtx.C, &genCtx.usrrefgrid);}
589   PetscOptionsEnd();
590 
591   ierr = DMMBUtil_InitializeOptions(genCtx, dim, useSimplex, global_rank, global_size, bounds, nele);CHKERRQ(ierr);
592 
593   //if(nele<nprocs) SETERRQ2(PETSC_COMM_WORLD,PETSC_ERR_ARG_OUTOFRANGE,"The dimensional discretization size should be greater or equal to number of processors: %D < %D",nele,nprocs);
594 
595   if (genCtx.adjEnts) genCtx.keep_skins = true; /* do not delete anything - consumes more memory */
596 
597   /* determine m, n, k for processor rank */
598   ml = nl = kl = 0;
599   switch (genCtx.dim) {
600   case 1:
601     ml = (genCtx.cumfraction);
602     break;
603   case 2:
604     nl = (genCtx.cumfraction);
605     break;
606   default:
607     kl = (genCtx.cumfraction) / genCtx.q / genCtx.blockSizeElementXYZ[2] / genCtx.C; //genCtx.K
608     break;
609   }
610 
611   /*
612    * so there are a total of M * A * blockSizeElement elements in x direction (so M * A * blockSizeElement + 1 verts in x direction)
613    * so there are a total of N * B * blockSizeElement elements in y direction (so N * B * blockSizeElement + 1 verts in y direction)
614    * so there are a total of K * C * blockSizeElement elements in z direction (so K * C * blockSizeElement + 1 verts in z direction)
615 
616    * there are ( M * A blockSizeElement )      *  ( N * B * blockSizeElement)      * (K * C * blockSizeElement )    hexas
617    * there are ( M * A * blockSizeElement + 1) *  ( N * B * blockSizeElement + 1 ) * (K * C * blockSizeElement + 1) vertices
618    * x is the first dimension that varies
619    */
620 
621   /* generate the block at (a, b, c); it will represent a partition , it will get a partition tag */
622   PetscInt dum_id = -1;
623   merr = mbImpl->tag_get_handle("GLOBAL_ID", 1, moab::MB_TYPE_INTEGER, global_id_tag);MBERR("Getting Global_ID Tag handle failed", merr);
624 
625   merr = mbImpl->tag_get_handle(MATERIAL_SET_TAG_NAME, 1, moab::MB_TYPE_INTEGER, mat_tag);MBERR("Getting Material set Tag handle failed", merr);
626   merr = mbImpl->tag_get_handle(DIRICHLET_SET_TAG_NAME, 1, moab::MB_TYPE_INTEGER, dir_tag);MBERR("Getting Dirichlet set Tag handle failed", merr);
627   merr = mbImpl->tag_get_handle(NEUMANN_SET_TAG_NAME, 1, moab::MB_TYPE_INTEGER, neu_tag);MBERR("Getting Neumann set Tag handle failed", merr);
628 
629   merr = mbImpl->tag_get_handle("PARALLEL_PARTITION", 1, moab::MB_TYPE_INTEGER, part_tag, moab::MB_TAG_CREAT | moab::MB_TAG_SPARSE, &dum_id);MBERR("Getting Partition Tag handle failed", merr);
630 
631   /* lets create some sets */
632   merr = mbImpl->tag_get_handle(GEOM_DIMENSION_TAG_NAME, 1, moab::MB_TYPE_INTEGER, geom_tag, moab::MB_TAG_CREAT | moab::MB_TAG_SPARSE, &dum_id);MBERRNM(merr);
633   merr = mbImpl->create_meshset(moab::MESHSET_SET, regionset);MBERRNM(merr);
634   ierr = PetscLogEventEnd(genCtx.generateMesh, 0, 0, 0, 0);CHKERRQ(ierr);
635 
636   for (a = 0; a < (genCtx.dim > 0 ? genCtx.A : genCtx.A); a++) {
637     for (b = 0; b < (genCtx.dim > 1 ? genCtx.B : 1); b++) {
638       for (c = 0; c < (genCtx.dim > 2 ? genCtx.C : 1); c++) {
639 
640         moab::EntityHandle startv;
641 
642         ierr = PetscLogEventBegin(genCtx.generateVertices, 0, 0, 0, 0);CHKERRQ(ierr);
643         ierr = DMMoab_GenerateVertices_Private(mbImpl, readMeshIface, genCtx, ml, nl, kl, a, b, c, global_id_tag, startv, verts);CHKERRQ(ierr);
644         ierr = PetscLogEventEnd(genCtx.generateVertices, 0, 0, 0, 0);CHKERRQ(ierr);
645 
646         ierr = PetscLogEventBegin(genCtx.generateElements, 0, 0, 0, 0);CHKERRQ(ierr);
647         ierr = DMMoab_GenerateElements_Private(mbImpl, readMeshIface, genCtx, ml, nl, kl, a, b, c, global_id_tag, startv, cells);CHKERRQ(ierr);
648         ierr = PetscLogEventEnd(genCtx.generateElements, 0, 0, 0, 0);CHKERRQ(ierr);
649 
650         PetscInt part_num = 0;
651         switch (genCtx.dim) {
652         case 3:
653           part_num += (c + kl * genCtx.C) * (genCtx.M * genCtx.A * genCtx.N * genCtx.B);
654         case 2:
655           part_num += (b + nl * genCtx.B) * (genCtx.M * genCtx.A);
656         case 1:
657           part_num += (a + ml * genCtx.A);
658           break;
659         }
660 
661         moab::EntityHandle part_set;
662         merr = mbImpl->create_meshset(moab::MESHSET_SET, part_set);MBERR("Can't create mesh set.", merr);
663 
664         merr = mbImpl->add_entities(part_set, verts);MBERR("Can't add vertices to set.", merr);
665         merr = mbImpl->add_entities(part_set, cells);MBERR("Can't add entities to set.", merr);
666         merr = mbImpl->add_entities(regionset, cells);MBERR("Can't add entities to set.", merr);
667 
668         /* if needed, add all edges and faces */
669         if (genCtx.adjEnts)
670         {
671           if (genCtx.dim > 1) {
672             merr = mbImpl->get_adjacencies(cells, 1, true, edges, moab::Interface::UNION);MBERR("Can't get edges", merr);
673             merr = mbImpl->add_entities(part_set, edges);MBERR("Can't add edges to partition set.", merr);
674           }
675           if (genCtx.dim > 2) {
676             merr = mbImpl->get_adjacencies(cells, 2, true, faces, moab::Interface::UNION);MBERR("Can't get faces", merr);
677             merr = mbImpl->add_entities(part_set, faces);MBERR("Can't add faces to partition set.", merr);
678           }
679           edges.clear();
680           faces.clear();
681         }
682         verts.clear(); cells.clear();
683 
684         merr = mbImpl->tag_set_data(part_tag, &part_set, 1, &part_num);MBERR("Can't set part tag on set", merr);
685         if (dmmoab->fileset) {
686           merr = mbImpl->add_parent_child(dmmoab->fileset, part_set);MBERR("Can't add part set to file set.", merr);
687           merr = mbImpl->unite_meshset(dmmoab->fileset, part_set);MBERRNM(merr);
688         }
689         merr = mbImpl->add_entities(dmmoab->fileset, &part_set, 1);MBERRNM(merr);
690       }
691     }
692   }
693 
694   merr = mbImpl->add_parent_child(dmmoab->fileset, regionset);MBERRNM(merr);
695 
696   /* Only in parallel: resolve shared entities between processors and exchange ghost layers */
697   if (global_size > 1) {
698 
699     ierr = PetscLogEventBegin(genCtx.parResolve, 0, 0, 0, 0);CHKERRQ(ierr);
700 
701     merr = mbImpl->get_entities_by_dimension(dmmoab->fileset, genCtx.dim, cells);MBERR("Can't get all d-dimensional elements.", merr);
702     merr = mbImpl->get_entities_by_dimension(dmmoab->fileset, 0, verts);MBERR("Can't get all vertices.", merr);
703 
704     if (genCtx.A * genCtx.B * genCtx.C != 1) { //  merge needed
705       moab::MergeMesh mm(mbImpl);
706       if (genCtx.newMergeMethod) {
707         merr = mm.merge_using_integer_tag(verts, global_id_tag);MBERR("Can't merge with GLOBAL_ID tag", merr);
708       }
709       else {
710         merr = mm.merge_entities(cells, 0.0001);MBERR("Can't merge with coordinates", merr);
711       }
712     }
713 
714 #ifdef MOAB_HAVE_MPI
715     /* check the handles */
716     merr = pcomm->check_all_shared_handles();MBERRV(mbImpl, merr);
717 
718     /* resolve the shared entities by exchanging information to adjacent processors */
719     merr = pcomm->resolve_shared_ents(dmmoab->fileset, cells, dim, dim - 1, NULL, &global_id_tag);MBERRV(mbImpl, merr);
720     if (dmmoab->fileset) {
721       merr = pcomm->exchange_ghost_cells(dim, 0, nghost, dim, true, false, &dmmoab->fileset);MBERRV(mbImpl, merr);
722     }
723     else {
724       merr = pcomm->exchange_ghost_cells(dim, 0, nghost, dim, true, false);MBERRV(mbImpl, merr);
725     }
726 
727     /* Reassign global IDs on all entities. */
728     merr = pcomm->assign_global_ids(dmmoab->fileset, dim, 1, false, true, false);MBERRNM(merr);
729 #endif
730 
731     ierr = PetscLogEventEnd(genCtx.parResolve, 0, 0, 0, 0);CHKERRQ(ierr);
732   }
733 
734   if (!genCtx.keep_skins) { // default is to delete the 1- and 2-dimensional entities
735     // delete all quads and edges
736     moab::Range toDelete;
737     if (genCtx.dim > 1) {
738       merr = mbImpl->get_entities_by_dimension(dmmoab->fileset, 1, toDelete);MBERR("Can't get edges", merr);
739     }
740 
741     if (genCtx.dim > 2) {
742       merr = mbImpl->get_entities_by_dimension(dmmoab->fileset, 2, toDelete);MBERR("Can't get faces", merr);
743     }
744 
745 #ifdef MOAB_HAVE_MPI
746     merr = dmmoab->pcomm->delete_entities(toDelete) ;MBERR("Can't delete entities", merr);
747 #endif
748   }
749 
750   /* set geometric dimension tag for regions */
751   merr = mbImpl->tag_set_data(geom_tag, &regionset, 1, &dmmoab->dim);MBERRNM(merr);
752   /* set default material ID for regions */
753   int default_material = 1;
754   merr = mbImpl->tag_set_data(mat_tag, &regionset, 1, &default_material);MBERRNM(merr);
755   /*
756     int default_dbc = 0;
757     merr = mbImpl->tag_set_data(dir_tag, &vertexset, 1, &default_dbc);MBERRNM(merr);
758   */
759   PetscFunctionReturn(0);
760 }
761 
762 
763 PetscErrorCode DMMoab_GetReadOptions_Private(PetscBool by_rank, PetscInt numproc, PetscInt dim, PetscInt nghost, MoabReadMode mode, PetscInt dbglevel, const char* dm_opts, const char* extra_opts, const char** read_opts)
764 {
765   char           *ropts;
766   char           ropts_par[PETSC_MAX_PATH_LEN], ropts_pargh[PETSC_MAX_PATH_LEN];
767   char           ropts_dbg[PETSC_MAX_PATH_LEN];
768   PetscErrorCode ierr;
769 
770   PetscFunctionBegin;
771   ierr = PetscMalloc1(PETSC_MAX_PATH_LEN, &ropts);CHKERRQ(ierr);
772   ierr = PetscMemzero(&ropts_par, PETSC_MAX_PATH_LEN);CHKERRQ(ierr);
773   ierr = PetscMemzero(&ropts_pargh, PETSC_MAX_PATH_LEN);CHKERRQ(ierr);
774   ierr = PetscMemzero(&ropts_dbg, PETSC_MAX_PATH_LEN);CHKERRQ(ierr);
775 
776   /* do parallel read unless using only one processor */
777   if (numproc > 1) {
778     // ierr = PetscSNPrintf(ropts_par, PETSC_MAX_PATH_LEN, "PARALLEL=%s;PARTITION=PARALLEL_PARTITION;PARTITION_DISTRIBUTE;PARALLEL_RESOLVE_SHARED_ENTS;PARALLEL_GHOSTS=%d.0.1%s;",MoabReadModes[mode],dim,(by_rank ? ";PARTITION_BY_RANK":""));CHKERRQ(ierr);
779     ierr = PetscSNPrintf(ropts_par, PETSC_MAX_PATH_LEN, "PARALLEL=%s;PARTITION=PARALLEL_PARTITION;PARTITION_DISTRIBUTE;PARALLEL_RESOLVE_SHARED_ENTS;%s", MoabReadModes[mode], (by_rank ? "PARTITION_BY_RANK;" : ""));CHKERRQ(ierr);
780     if (nghost) {
781       ierr = PetscSNPrintf(ropts_pargh, PETSC_MAX_PATH_LEN, "PARALLEL_GHOSTS=%d.0.%d;", dim, nghost);CHKERRQ(ierr);
782     }
783   }
784 
785   if (dbglevel) {
786     if (numproc > 1) {
787       ierr = PetscSNPrintf(ropts_dbg, PETSC_MAX_PATH_LEN, "CPUTIME;DEBUG_IO=%d;DEBUG_PIO=%d;", dbglevel, dbglevel);CHKERRQ(ierr);
788     }
789     else {
790       ierr = PetscSNPrintf(ropts_dbg, PETSC_MAX_PATH_LEN, "CPUTIME;DEBUG_IO=%d;", dbglevel);CHKERRQ(ierr);
791     }
792   }
793 
794   ierr = PetscSNPrintf(ropts, PETSC_MAX_PATH_LEN, "%s%s%s%s%s", ropts_par, (nghost ? ropts_pargh : ""), ropts_dbg, (extra_opts ? extra_opts : ""), (dm_opts ? dm_opts : ""));CHKERRQ(ierr);
795   *read_opts = ropts;
796   PetscFunctionReturn(0);
797 }
798 
799 
800 /*@
801   DMMoabLoadFromFile - Creates a DM object by loading the mesh from a user specified file.
802 
803   Collective on MPI_Comm
804 
805   Input Parameters:
806 + comm - The communicator for the DM object
807 . dim - The spatial dimension
808 . filename - The name of the mesh file to be loaded
809 . usrreadopts - The options string to read a MOAB mesh.
810   Reference (Parallel Mesh Initialization: http://www.mcs.anl.gov/~fathom/moab-docs/html/contents.html#fivetwo)
811 
812   Output Parameter:
813 . dm  - The DM object
814 
815   Level: beginner
816 
817 .keywords: DM, create
818 
819 .seealso: DMSetType(), DMCreate(), DMMoabCreateBoxMesh()
820 @*/
821 PetscErrorCode DMMoabLoadFromFile(MPI_Comm comm, PetscInt dim, PetscInt nghost, const char* filename, const char* usrreadopts, DM *dm)
822 {
823   moab::ErrorCode     merr;
824   PetscInt            nprocs;
825   DM_Moab            *dmmoab;
826   moab::Interface    *mbiface;
827 #ifdef MOAB_HAVE_MPI
828   moab::ParallelComm *pcomm;
829 #endif
830   moab::Range         verts, elems;
831   const char         *readopts;
832   PetscErrorCode      ierr;
833 
834   PetscFunctionBegin;
835   PetscValidPointer(dm, 6);
836 
837   /* Create the basic DMMoab object and keep the default parameters created by DM impls */
838   ierr = DMMoabCreateMoab(comm, NULL, NULL, NULL, dm);CHKERRQ(ierr);
839 
840   /* get all the necessary handles from the private DM object */
841   dmmoab = (DM_Moab*)(*dm)->data;
842   mbiface = dmmoab->mbiface;
843 #ifdef MOAB_HAVE_MPI
844   pcomm = dmmoab->pcomm;
845   nprocs = pcomm->size();
846 #else
847   nprocs = 1;
848 #endif
849   /* TODO: Decipher dimension based on the loaded mesh instead of getting from user */
850   dmmoab->dim = dim;
851   dmmoab->nghostrings = nghost;
852   dmmoab->refct = 1;
853 
854   /* create a file set to associate all entities in current mesh */
855   merr = dmmoab->mbiface->create_meshset(moab::MESHSET_SET, dmmoab->fileset);MBERR("Creating file set failed", merr);
856 
857   /* add mesh loading options specific to the DM */
858   ierr = DMMoab_GetReadOptions_Private(dmmoab->partition_by_rank, nprocs, dim, nghost, dmmoab->read_mode,
859                                        dmmoab->rw_dbglevel, dmmoab->extra_read_options, usrreadopts, &readopts);CHKERRQ(ierr);
860 
861   PetscInfo2(*dm, "Reading file %s with options: %s\n", filename, readopts);
862 
863   /* Load the mesh from a file. */
864   if (dmmoab->fileset) {
865     merr = mbiface->load_file(filename, &dmmoab->fileset, readopts);MBERRVM(mbiface, "Reading MOAB file failed.", merr);
866   }
867   else {
868     merr = mbiface->load_file(filename, 0, readopts);MBERRVM(mbiface, "Reading MOAB file failed.", merr);
869   }
870 
871 #ifdef MOAB_HAVE_MPI
872   /* Reassign global IDs on all entities. */
873   /* merr = pcomm->assign_global_ids(dmmoab->fileset, dim, 1, true, true, true);MBERRNM(merr); */
874 #endif
875 
876   /* load the local vertices */
877   merr = mbiface->get_entities_by_type(dmmoab->fileset, moab::MBVERTEX, verts, true);MBERRNM(merr);
878   /* load the local elements */
879   merr = mbiface->get_entities_by_dimension(dmmoab->fileset, dim, elems, true);MBERRNM(merr);
880 
881 #ifdef MOAB_HAVE_MPI
882   /* Everything is set up, now just do a tag exchange to update tags
883      on all of the ghost vertexes */
884   merr = pcomm->exchange_tags(dmmoab->ltog_tag, verts);MBERRV(mbiface, merr);
885   merr = pcomm->exchange_tags(dmmoab->ltog_tag, elems);MBERRV(mbiface, merr);
886   merr = pcomm->collective_sync_partition();MBERR("Collective sync failed", merr);
887 #endif
888 
889   PetscInfo3(*dm, "MOAB file '%s' was successfully loaded. Found %D vertices and %D elements.\n", filename, verts.size(), elems.size());
890   ierr = PetscFree(readopts);CHKERRQ(ierr);
891   PetscFunctionReturn(0);
892 }
893 
894 
895 /*@
896   DMMoabRenumberMeshEntities - Order and number all entities (vertices->elements) to be contiguously ordered
897   in parallel
898 
899   Collective on MPI_Comm
900 
901   Input Parameters:
902 + dm  - The DM object
903 
904   Level: advanced
905 
906 .keywords: DM, reorder
907 
908 .seealso: DMSetUp(), DMCreate()
909 @*/
910 PetscErrorCode DMMoabRenumberMeshEntities(DM dm)
911 {
912   moab::Range         verts;
913 
914   PetscFunctionBegin;
915   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
916 
917 #ifdef MOAB_HAVE_MPI
918   /* Insert new points */
919   moab::ErrorCode     merr;
920   merr = ((DM_Moab*) dm->data)->pcomm->assign_global_ids(((DM_Moab*) dm->data)->fileset, 3, 0, false, true, false);MBERRNM(merr);
921 #endif
922   PetscFunctionReturn(0);
923 }
924 
925