Actual source code: plexorient.c

  1: #include <petsc/private/dmpleximpl.h>
  2: #include <petscsf.h>
  3: #include <petsc/private/hashsetij.h>

  5: /*@
  6:   DMPlexOrientPoint - Act with the given orientation on the cone points of this mesh point, and update its use in the mesh.

  8:   Not Collective

 10:   Input Parameters:
 11: + dm - The `DM`
 12: . p  - The mesh point
 13: - o  - The orientation

 15:   Level: intermediate

 17: .seealso: [](ch_unstructured), `DM`, `DMPLEX`, `DMPlexOrient()`, `DMPlexGetCone()`, `DMPlexGetConeOrientation()`, `DMPlexInterpolate()`, `DMPlexGetChart()`
 18: @*/
 19: PetscErrorCode DMPlexOrientPoint(DM dm, PetscInt p, PetscInt o)
 20: {
 21:   DMPolytopeType  ct;
 22:   const PetscInt *arr, *cone, *ornt, *support;
 23:   PetscInt       *newcone, *newornt;
 24:   PetscInt        coneSize, c, supportSize, s;

 26:   PetscFunctionBegin;
 28:   PetscCall(DMPlexGetCellType(dm, p, &ct));
 29:   arr = DMPolytopeTypeGetArrangement(ct, o);
 30:   if (!arr) PetscFunctionReturn(PETSC_SUCCESS);
 31:   PetscCall(DMPlexGetConeSize(dm, p, &coneSize));
 32:   PetscCall(DMPlexGetCone(dm, p, &cone));
 33:   PetscCall(DMPlexGetConeOrientation(dm, p, &ornt));
 34:   PetscCall(DMGetWorkArray(dm, coneSize, MPIU_INT, &newcone));
 35:   PetscCall(DMGetWorkArray(dm, coneSize, MPIU_INT, &newornt));
 36:   for (c = 0; c < coneSize; ++c) {
 37:     DMPolytopeType ft;
 38:     PetscInt       nO;

 40:     PetscCall(DMPlexGetCellType(dm, cone[c], &ft));
 41:     nO         = DMPolytopeTypeGetNumArrangements(ft) / 2;
 42:     newcone[c] = cone[arr[c * 2 + 0]];
 43:     newornt[c] = DMPolytopeTypeComposeOrientation(ft, arr[c * 2 + 1], ornt[arr[c * 2 + 0]]);
 44:     PetscCheck(!newornt[c] || !(newornt[c] >= nO || newornt[c] < -nO), PETSC_COMM_SELF, PETSC_ERR_PLIB, "Invalid orientation %" PetscInt_FMT " not in [%" PetscInt_FMT ",%" PetscInt_FMT ") for %s %" PetscInt_FMT, newornt[c], -nO, nO, DMPolytopeTypes[ft], cone[c]);
 45:   }
 46:   PetscCall(DMPlexSetCone(dm, p, newcone));
 47:   PetscCall(DMPlexSetConeOrientation(dm, p, newornt));
 48:   PetscCall(DMRestoreWorkArray(dm, coneSize, MPIU_INT, &newcone));
 49:   PetscCall(DMRestoreWorkArray(dm, coneSize, MPIU_INT, &newornt));
 50:   /* Update orientation of this point in the support points */
 51:   PetscCall(DMPlexGetSupportSize(dm, p, &supportSize));
 52:   PetscCall(DMPlexGetSupport(dm, p, &support));
 53:   for (s = 0; s < supportSize; ++s) {
 54:     PetscCall(DMPlexGetConeSize(dm, support[s], &coneSize));
 55:     PetscCall(DMPlexGetCone(dm, support[s], &cone));
 56:     PetscCall(DMPlexGetConeOrientation(dm, support[s], &ornt));
 57:     for (c = 0; c < coneSize; ++c) {
 58:       PetscInt po;

 60:       if (cone[c] != p) continue;
 61:       /* ornt[c] * 0 = target = po * o so that po = ornt[c] * o^{-1} */
 62:       po = DMPolytopeTypeComposeOrientationInv(ct, ornt[c], o);
 63:       PetscCall(DMPlexInsertConeOrientation(dm, support[s], c, po));
 64:     }
 65:   }
 66:   PetscFunctionReturn(PETSC_SUCCESS);
 67: }

 69: static PetscInt GetPointIndex(PetscInt point, PetscInt pStart, PetscInt pEnd, const PetscInt points[])
 70: {
 71:   if (points) {
 72:     PetscInt loc;

 74:     PetscCallAbort(PETSC_COMM_SELF, PetscFindInt(point, pEnd - pStart, points, &loc));
 75:     if (loc >= 0) return loc;
 76:   } else {
 77:     if (point >= pStart && point < pEnd) return point - pStart;
 78:   }
 79:   return -1;
 80: }

 82: /*
 83:   - Checks face match
 84:     - Flips non-matching
 85:   - Inserts faces of support cells in FIFO
 86: */
 87: static PetscErrorCode DMPlexCheckFace_Internal(DM dm, PetscInt *faceFIFO, PetscInt *fTop, PetscInt *fBottom, IS cellIS, IS faceIS, PetscBT seenCells, PetscBT flippedCells, PetscBT seenFaces)
 88: {
 89:   const PetscInt *supp, *coneA, *coneB, *coneOA, *coneOB;
 90:   PetscInt        suppSize, Ns = 0, coneSizeA, coneSizeB, posA = -1, posB = -1;
 91:   PetscInt        face, dim, indC[3], indS[3], seenA, flippedA, seenB, flippedB, mismatch;
 92:   const PetscInt *cells, *faces;
 93:   PetscInt        cStart, cEnd, fStart, fEnd;

 95:   PetscFunctionBegin;
 96:   face = faceFIFO[(*fTop)++];
 97:   PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
 98:   PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
 99:   PetscCall(DMPlexGetPointDepth(dm, cells ? cells[cStart] : cStart, &dim));
100:   PetscCall(DMPlexGetSupportSize(dm, face, &suppSize));
101:   PetscCall(DMPlexGetSupport(dm, face, &supp));
102:   // Filter the support
103:   for (PetscInt s = 0; s < suppSize; ++s) {
104:     // Filter support
105:     indC[Ns] = GetPointIndex(supp[s], cStart, cEnd, cells);
106:     indS[Ns] = s;
107:     if (indC[Ns] >= 0) ++Ns;
108:   }
109:   if (Ns < 2) PetscFunctionReturn(PETSC_SUCCESS);
110:   PetscCheck(Ns == 2, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Faces should separate only two cells, not %" PetscInt_FMT, Ns);
111:   PetscCheck(indC[0] >= 0 && indC[1] >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Support cells %" PetscInt_FMT " (%" PetscInt_FMT ") and %" PetscInt_FMT " (%" PetscInt_FMT ") are not both valid", supp[0], indC[0], supp[1], indC[1]);
112:   seenA    = PetscBTLookup(seenCells, indC[0]);
113:   flippedA = PetscBTLookup(flippedCells, indC[0]) ? 1 : 0;
114:   seenB    = PetscBTLookup(seenCells, indC[1]);
115:   flippedB = PetscBTLookup(flippedCells, indC[1]) ? 1 : 0;

117:   PetscCall(DMPlexGetConeSize(dm, supp[indS[0]], &coneSizeA));
118:   PetscCall(DMPlexGetConeSize(dm, supp[indS[1]], &coneSizeB));
119:   PetscCall(DMPlexGetCone(dm, supp[indS[0]], &coneA));
120:   PetscCall(DMPlexGetCone(dm, supp[indS[1]], &coneB));
121:   PetscCall(DMPlexGetConeOrientation(dm, supp[indS[0]], &coneOA));
122:   PetscCall(DMPlexGetConeOrientation(dm, supp[indS[1]], &coneOB));
123:   for (PetscInt c = 0; c < coneSizeA; ++c) {
124:     const PetscInt indF = GetPointIndex(coneA[c], fStart, fEnd, faces);

126:     // Filter cone
127:     if (indF < 0) continue;
128:     if (!PetscBTLookup(seenFaces, indF)) {
129:       faceFIFO[(*fBottom)++] = coneA[c];
130:       PetscCall(PetscBTSet(seenFaces, indF));
131:     }
132:     if (coneA[c] == face) posA = c;
133:     PetscCheck(*fBottom <= fEnd - fStart, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Face %" PetscInt_FMT " was pushed exceeding capacity %" PetscInt_FMT " > %" PetscInt_FMT, coneA[c], *fBottom, fEnd - fStart);
134:   }
135:   PetscCheck(posA >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " could not be located in cell %" PetscInt_FMT, face, supp[indS[0]]);
136:   for (PetscInt c = 0; c < coneSizeB; ++c) {
137:     const PetscInt indF = GetPointIndex(coneB[c], fStart, fEnd, faces);

139:     // Filter cone
140:     if (indF < 0) continue;
141:     if (!PetscBTLookup(seenFaces, indF)) {
142:       faceFIFO[(*fBottom)++] = coneB[c];
143:       PetscCall(PetscBTSet(seenFaces, indF));
144:     }
145:     if (coneB[c] == face) posB = c;
146:     PetscCheck(*fBottom <= fEnd - fStart, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Face %" PetscInt_FMT " was pushed exceeding capacity %" PetscInt_FMT " > %" PetscInt_FMT, coneA[c], *fBottom, fEnd - fStart);
147:   }
148:   PetscCheck(posB >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " could not be located in cell %" PetscInt_FMT, face, supp[indS[1]]);

150:   if (dim == 1) {
151:     mismatch = posA == posB;
152:   } else {
153:     mismatch = coneOA[posA] == coneOB[posB];
154:   }

156:   if (mismatch ^ (flippedA ^ flippedB)) {
157:     PetscCheck(!seenA || !seenB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Previously seen cells %" PetscInt_FMT " and %" PetscInt_FMT " do not match: Fault mesh is non-orientable", supp[indS[0]], supp[indS[1]]);
158:     if (!seenA && !flippedA) PetscCall(PetscBTSet(flippedCells, indC[0]));
159:     else {
160:       PetscCheck(!seenB && !flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Inconsistent mesh orientation: Fault mesh is non-orientable");
161:       PetscCall(PetscBTSet(flippedCells, indC[1]));
162:     }
163:   } else PetscCheck(!mismatch || !flippedA || !flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Attempt to flip already flipped cell: Fault mesh is non-orientable");
164:   PetscCall(PetscBTSet(seenCells, indC[0]));
165:   PetscCall(PetscBTSet(seenCells, indC[1]));
166:   PetscFunctionReturn(PETSC_SUCCESS);
167: }

169: static PetscErrorCode DMPlexCheckFace_Old_Internal(DM dm, PetscInt *faceFIFO, PetscInt *fTop, PetscInt *fBottom, PetscInt cStart, PetscInt fStart, PetscInt fEnd, PetscBT seenCells, PetscBT flippedCells, PetscBT seenFaces)
170: {
171:   const PetscInt *support, *coneA, *coneB, *coneOA, *coneOB;
172:   PetscInt        supportSize, coneSizeA, coneSizeB, posA = -1, posB = -1;
173:   PetscInt        face, dim, seenA, flippedA, seenB, flippedB, mismatch, c;

175:   PetscFunctionBegin;
176:   face = faceFIFO[(*fTop)++];
177:   PetscCall(DMGetDimension(dm, &dim));
178:   PetscCall(DMPlexGetSupportSize(dm, face, &supportSize));
179:   PetscCall(DMPlexGetSupport(dm, face, &support));
180:   if (supportSize < 2) PetscFunctionReturn(PETSC_SUCCESS);
181:   PetscCheck(supportSize == 2, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Faces should separate only two cells, not %" PetscInt_FMT, supportSize);
182:   seenA    = PetscBTLookup(seenCells, support[0] - cStart);
183:   flippedA = PetscBTLookup(flippedCells, support[0] - cStart) ? 1 : 0;
184:   seenB    = PetscBTLookup(seenCells, support[1] - cStart);
185:   flippedB = PetscBTLookup(flippedCells, support[1] - cStart) ? 1 : 0;

187:   PetscCall(DMPlexGetConeSize(dm, support[0], &coneSizeA));
188:   PetscCall(DMPlexGetConeSize(dm, support[1], &coneSizeB));
189:   PetscCall(DMPlexGetCone(dm, support[0], &coneA));
190:   PetscCall(DMPlexGetCone(dm, support[1], &coneB));
191:   PetscCall(DMPlexGetConeOrientation(dm, support[0], &coneOA));
192:   PetscCall(DMPlexGetConeOrientation(dm, support[1], &coneOB));
193:   for (c = 0; c < coneSizeA; ++c) {
194:     if (!PetscBTLookup(seenFaces, coneA[c] - fStart)) {
195:       faceFIFO[(*fBottom)++] = coneA[c];
196:       PetscCall(PetscBTSet(seenFaces, coneA[c] - fStart));
197:     }
198:     if (coneA[c] == face) posA = c;
199:     PetscCheck(*fBottom <= fEnd - fStart, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Face %" PetscInt_FMT " was pushed exceeding capacity %" PetscInt_FMT " > %" PetscInt_FMT, coneA[c], *fBottom, fEnd - fStart);
200:   }
201:   PetscCheck(posA >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " could not be located in cell %" PetscInt_FMT, face, support[0]);
202:   for (c = 0; c < coneSizeB; ++c) {
203:     if (!PetscBTLookup(seenFaces, coneB[c] - fStart)) {
204:       faceFIFO[(*fBottom)++] = coneB[c];
205:       PetscCall(PetscBTSet(seenFaces, coneB[c] - fStart));
206:     }
207:     if (coneB[c] == face) posB = c;
208:     PetscCheck(*fBottom <= fEnd - fStart, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Face %" PetscInt_FMT " was pushed exceeding capacity %" PetscInt_FMT " > %" PetscInt_FMT, coneA[c], *fBottom, fEnd - fStart);
209:   }
210:   PetscCheck(posB >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " could not be located in cell %" PetscInt_FMT, face, support[1]);

212:   if (dim == 1) {
213:     mismatch = posA == posB;
214:   } else {
215:     mismatch = coneOA[posA] == coneOB[posB];
216:   }

218:   if (mismatch ^ (flippedA ^ flippedB)) {
219:     PetscCheck(!seenA || !seenB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Previously seen cells %" PetscInt_FMT " and %" PetscInt_FMT " do not match: Fault mesh is non-orientable", support[0], support[1]);
220:     if (!seenA && !flippedA) {
221:       PetscCall(PetscBTSet(flippedCells, support[0] - cStart));
222:     } else if (!seenB && !flippedB) {
223:       PetscCall(PetscBTSet(flippedCells, support[1] - cStart));
224:     } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Inconsistent mesh orientation: Fault mesh is non-orientable");
225:   } else PetscCheck(!mismatch || !flippedA || !flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Attempt to flip already flipped cell: Fault mesh is non-orientable");
226:   PetscCall(PetscBTSet(seenCells, support[0] - cStart));
227:   PetscCall(PetscBTSet(seenCells, support[1] - cStart));
228:   PetscFunctionReturn(PETSC_SUCCESS);
229: }

231: /*
232:   DMPlexOrient_Serial - Compute valid orientation for local connected components

234:   Not collective

236:   Input Parameters:
237:   + dm         - The `DM`
238:   - cellHeight - The height of k-cells to be oriented

240:   Output Parameters:
241:   + Ncomp        - The number of connected component
242:   . cellComp     - The connected component for each local cell
243:   . faceComp     - The connected component for each local face
244:   - flippedCells - Marked cells should be inverted

246:   Level: developer

248: .seealso: `DMPlexOrient()`
249: */
250: static PetscErrorCode DMPlexOrient_Serial(DM dm, IS cellIS, IS faceIS, PetscInt *Ncomp, PetscInt cellComp[], PetscInt faceComp[], PetscBT flippedCells)
251: {
252:   PetscBT         seenCells, seenFaces;
253:   PetscInt       *faceFIFO;
254:   const PetscInt *cells = NULL, *faces = NULL;
255:   PetscInt        cStart = 0, cEnd = 0, fStart = 0, fEnd = 0;

257:   PetscFunctionBegin;
258:   /* Truth Table
259:      mismatch    flips   do action   mismatch   flipA ^ flipB   action
260:          F       0 flips     no         F             F           F
261:          F       1 flip      yes        F             T           T
262:          F       2 flips     no         T             F           T
263:          T       0 flips     yes        T             T           F
264:          T       1 flip      no
265:          T       2 flips     yes
266:   */
267:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
268:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
269:   PetscCall(PetscBTCreate(cEnd - cStart, &seenCells));
270:   PetscCall(PetscBTMemzero(cEnd - cStart, seenCells));
271:   PetscCall(PetscBTCreate(fEnd - fStart, &seenFaces));
272:   PetscCall(PetscBTMemzero(fEnd - fStart, seenFaces));
273:   PetscCall(PetscMalloc1(fEnd - fStart, &faceFIFO));
274:   *Ncomp = 0;
275:   for (PetscInt c = 0; c < cEnd - cStart; ++c) cellComp[c] = -1;
276:   do {
277:     PetscInt cc, fTop, fBottom;

279:     // Look for first unmarked cell
280:     for (cc = cStart; cc < cEnd; ++cc)
281:       if (cellComp[cc - cStart] < 0) break;
282:     if (cc >= cEnd) break;
283:     // Initialize FIFO with first cell in component
284:     {
285:       const PetscInt  cell = cells ? cells[cc] : cc;
286:       const PetscInt *cone;
287:       PetscInt        coneSize;

289:       fTop = fBottom = 0;
290:       PetscCall(DMPlexGetConeSize(dm, cell, &coneSize));
291:       PetscCall(DMPlexGetCone(dm, cell, &cone));
292:       for (PetscInt c = 0; c < coneSize; ++c) {
293:         const PetscInt idx = GetPointIndex(cone[c], fStart, fEnd, faces);

295:         // Cell faces are guaranteed to be in the face set
296:         PetscCheck(idx >= 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " of cell %" PetscInt_FMT " is not present in the label", cone[c], cell);
297:         faceFIFO[fBottom++] = cone[c];
298:         PetscCall(PetscBTSet(seenFaces, idx));
299:       }
300:       PetscCall(PetscBTSet(seenCells, cc - cStart));
301:     }
302:     // Consider each face in FIFO
303:     while (fTop < fBottom) PetscCall(DMPlexCheckFace_Internal(dm, faceFIFO, &fTop, &fBottom, cellIS, faceIS, seenCells, flippedCells, seenFaces));
304:     // Set component for cells and faces
305:     for (PetscInt c = 0; c < cEnd - cStart; ++c) {
306:       if (PetscBTLookup(seenCells, c)) cellComp[c] = *Ncomp;
307:     }
308:     for (PetscInt f = 0; f < fEnd - fStart; ++f) {
309:       if (PetscBTLookup(seenFaces, f)) faceComp[f] = *Ncomp;
310:     }
311:     // Wipe seenCells and seenFaces for next component
312:     PetscCall(PetscBTMemzero(fEnd - fStart, seenFaces));
313:     PetscCall(PetscBTMemzero(cEnd - cStart, seenCells));
314:     ++(*Ncomp);
315:   } while (1);
316:   PetscCall(PetscBTDestroy(&seenCells));
317:   PetscCall(PetscBTDestroy(&seenFaces));
318:   PetscCall(PetscFree(faceFIFO));
319:   for (PetscInt c = 0; c < cEnd - cStart; ++c)
320:     PetscCheck(0 <= cellComp[c] && cellComp[c] < *Ncomp, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid component %" PetscInt_FMT " for cell %" PetscInt_FMT " (%" PetscInt_FMT ")", cellComp[c], cells ? cells[c] : c, c);
321:   for (PetscInt f = 0; f < fEnd - fStart; ++f)
322:     PetscCheck(0 <= faceComp[f] && faceComp[f] < *Ncomp, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid component %" PetscInt_FMT " for face %" PetscInt_FMT " (%" PetscInt_FMT ")", faceComp[f], faces ? faces[f] : f, f);
323:   PetscFunctionReturn(PETSC_SUCCESS);
324: }

326: /*@
327:   DMPlexOrient - Give a consistent orientation to the input mesh

329:   Input Parameter:
330: . dm - The `DM`

332:   Note:
333:   The orientation data for the `DM` are change in-place.

335:   This routine will fail for non-orientable surfaces, such as the Moebius strip.

337:   Level: advanced

339: .seealso: [](ch_unstructured), `DM`, `DMPLEX`, `DMCreate()`
340: @*/
341: PetscErrorCode DMPlexOrient(DM dm)
342: {
343: #if 0
344:   IS cellIS, faceIS;

346:   PetscFunctionBegin;
347:   PetscCall(DMPlexGetAllCells_Internal(dm, &cellIS));
348:   PetscCall(DMPlexGetAllFaces_Internal(dm, &faceIS));
349:   PetscCall(DMPlexOrientCells_Internal(dm, cellIS, faceIS));
350:   PetscCall(ISDestroy(&cellIS));
351:   PetscCall(ISDestroy(&faceIS));
352:   PetscFunctionReturn(PETSC_SUCCESS);
353: #else
354:   MPI_Comm           comm;
355:   PetscSF            sf;
356:   const PetscInt    *lpoints;
357:   const PetscSFNode *rpoints;
358:   PetscSFNode       *rorntComp = NULL, *lorntComp = NULL;
359:   PetscInt          *numNeighbors, **neighbors, *locSupport = NULL;
360:   PetscSFNode       *nrankComp;
361:   PetscBool         *match, *flipped;
362:   PetscBT            seenCells, flippedCells, seenFaces;
363:   PetscInt          *faceFIFO, fTop, fBottom, *cellComp, *faceComp;
364:   PetscInt           numLeaves, numRoots, dim, h, cStart, cEnd, c, cell, fStart, fEnd, face, off, totNeighbors = 0;
365:   PetscMPIInt        rank, size, numComponents, comp = 0;
366:   PetscBool          flg, flg2;
367:   PetscViewer        viewer = NULL, selfviewer = NULL;

369:   PetscFunctionBegin;
370:   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
371:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
372:   PetscCallMPI(MPI_Comm_size(comm, &size));
373:   PetscCall(PetscOptionsHasName(((PetscObject)dm)->options, ((PetscObject)dm)->prefix, "-orientation_view", &flg));
374:   PetscCall(PetscOptionsHasName(((PetscObject)dm)->options, ((PetscObject)dm)->prefix, "-orientation_view_synchronized", &flg2));
375:   PetscCall(DMGetPointSF(dm, &sf));
376:   PetscCall(PetscSFGetGraph(sf, &numRoots, &numLeaves, &lpoints, &rpoints));
377:   /* Truth Table
378:      mismatch    flips   do action   mismatch   flipA ^ flipB   action
379:          F       0 flips     no         F             F           F
380:          F       1 flip      yes        F             T           T
381:          F       2 flips     no         T             F           T
382:          T       0 flips     yes        T             T           F
383:          T       1 flip      no
384:          T       2 flips     yes
385:   */
386:   PetscCall(DMGetDimension(dm, &dim));
387:   PetscCall(DMPlexGetVTKCellHeight(dm, &h));
388:   PetscCall(DMPlexGetHeightStratum(dm, h, &cStart, &cEnd));
389:   PetscCall(DMPlexGetHeightStratum(dm, h + 1, &fStart, &fEnd));
390:   PetscCall(PetscBTCreate(cEnd - cStart, &seenCells));
391:   PetscCall(PetscBTMemzero(cEnd - cStart, seenCells));
392:   PetscCall(PetscBTCreate(cEnd - cStart, &flippedCells));
393:   PetscCall(PetscBTMemzero(cEnd - cStart, flippedCells));
394:   PetscCall(PetscBTCreate(fEnd - fStart, &seenFaces));
395:   PetscCall(PetscBTMemzero(fEnd - fStart, seenFaces));
396:   PetscCall(PetscCalloc3(fEnd - fStart, &faceFIFO, cEnd - cStart, &cellComp, fEnd - fStart, &faceComp));
397:   /*
398:    OLD STYLE
399:    - Add an integer array over cells and faces (component) for connected component number
400:    Foreach component
401:      - Mark the initial cell as seen
402:      - Process component as usual
403:      - Set component for all seenCells
404:      - Wipe seenCells and seenFaces (flippedCells can stay)
405:    - Generate parallel adjacency for component using SF and seenFaces
406:    - Collect numComponents adj data from each proc to 0
407:    - Build same serial graph
408:    - Use same solver
409:    - Use Scatterv to send back flipped flags for each component
410:    - Negate flippedCells by component

412:    NEW STYLE
413:    - Create the adj on each process
414:    - Bootstrap to complete graph on proc 0
415:   */
416:   /* Loop over components */
417:   for (cell = cStart; cell < cEnd; ++cell) cellComp[cell - cStart] = -1;
418:   do {
419:     /* Look for first unmarked cell */
420:     for (cell = cStart; cell < cEnd; ++cell)
421:       if (cellComp[cell - cStart] < 0) break;
422:     if (cell >= cEnd) break;
423:     /* Initialize FIFO with first cell in component */
424:     {
425:       const PetscInt *cone;
426:       PetscInt        coneSize;

428:       fTop = fBottom = 0;
429:       PetscCall(DMPlexGetConeSize(dm, cell, &coneSize));
430:       PetscCall(DMPlexGetCone(dm, cell, &cone));
431:       for (c = 0; c < coneSize; ++c) {
432:         faceFIFO[fBottom++] = cone[c];
433:         PetscCall(PetscBTSet(seenFaces, cone[c] - fStart));
434:       }
435:       PetscCall(PetscBTSet(seenCells, cell - cStart));
436:     }
437:     /* Consider each face in FIFO */
438:     while (fTop < fBottom) PetscCall(DMPlexCheckFace_Old_Internal(dm, faceFIFO, &fTop, &fBottom, cStart, fStart, fEnd, seenCells, flippedCells, seenFaces));
439:     /* Set component for cells and faces */
440:     for (cell = 0; cell < cEnd - cStart; ++cell) {
441:       if (PetscBTLookup(seenCells, cell)) cellComp[cell] = comp;
442:     }
443:     for (face = 0; face < fEnd - fStart; ++face) {
444:       if (PetscBTLookup(seenFaces, face)) faceComp[face] = comp;
445:     }
446:     /* Wipe seenCells and seenFaces for next component */
447:     PetscCall(PetscBTMemzero(fEnd - fStart, seenFaces));
448:     PetscCall(PetscBTMemzero(cEnd - cStart, seenCells));
449:     ++comp;
450:   } while (1);
451:   numComponents = comp;
452:   if (flg) {
453:     PetscViewer v;

455:     PetscCall(PetscViewerASCIIGetStdout(comm, &v));
456:     PetscCall(PetscViewerASCIIPushSynchronized(v));
457:     PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]BT for serial flipped cells:\n", rank));
458:     PetscCall(PetscBTView(cEnd - cStart, flippedCells, v));
459:     PetscCall(PetscViewerFlush(v));
460:     PetscCall(PetscViewerASCIIPopSynchronized(v));
461:   }
462:   /* Now all subdomains are oriented, but we need a consistent parallel orientation */
463:   if (numLeaves >= 0) {
464:     PetscInt maxSupportSize, neighbor;

466:     /* Store orientations of boundary faces*/
467:     PetscCall(DMPlexGetMaxSizes(dm, NULL, &maxSupportSize));
468:     PetscCall(PetscCalloc3(numRoots, &rorntComp, numRoots, &lorntComp, maxSupportSize, &locSupport));
469:     for (face = fStart; face < fEnd; ++face) {
470:       const PetscInt *cone, *support, *ornt;
471:       PetscInt        coneSize, supportSize, Ns = 0, s, l;

473:       PetscCall(DMPlexGetSupportSize(dm, face, &supportSize));
474:       /* Ignore overlapping cells */
475:       PetscCall(DMPlexGetSupport(dm, face, &support));
476:       for (s = 0; s < supportSize; ++s) {
477:         if (lpoints) PetscCall(PetscFindInt(support[s], numLeaves, lpoints, &l));
478:         else {
479:           if (support[s] >= 0 && support[s] < numLeaves) l = support[s];
480:           else l = -1;
481:         }
482:         if (l >= 0) continue;
483:         locSupport[Ns++] = support[s];
484:       }
485:       if (Ns != 1) continue;
486:       neighbor = locSupport[0];
487:       PetscCall(DMPlexGetCone(dm, neighbor, &cone));
488:       PetscCall(DMPlexGetConeSize(dm, neighbor, &coneSize));
489:       PetscCall(DMPlexGetConeOrientation(dm, neighbor, &ornt));
490:       for (c = 0; c < coneSize; ++c)
491:         if (cone[c] == face) break;
492:       if (dim == 1) {
493:         /* Use cone position instead, shifted to -1 or 1 */
494:         if (PetscBTLookup(flippedCells, neighbor - cStart)) rorntComp[face].rank = 1 - c * 2;
495:         else rorntComp[face].rank = c * 2 - 1;
496:       } else {
497:         if (PetscBTLookup(flippedCells, neighbor - cStart)) rorntComp[face].rank = ornt[c] < 0 ? -1 : 1;
498:         else rorntComp[face].rank = ornt[c] < 0 ? 1 : -1;
499:       }
500:       rorntComp[face].index = faceComp[face - fStart];
501:     }
502:     /* Communicate boundary edge orientations */
503:     PetscCall(PetscSFBcastBegin(sf, MPIU_SF_NODE, rorntComp, lorntComp, MPI_REPLACE));
504:     PetscCall(PetscSFBcastEnd(sf, MPIU_SF_NODE, rorntComp, lorntComp, MPI_REPLACE));
505:   }
506:   /* Get process adjacency */
507:   PetscCall(PetscMalloc2(numComponents, &numNeighbors, numComponents, &neighbors));
508:   viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)dm));
509:   if (flg2) PetscCall(PetscViewerASCIIPushSynchronized(viewer));
510:   PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
511:   for (comp = 0; comp < numComponents; ++comp) {
512:     PetscInt n;

514:     numNeighbors[comp] = 0;
515:     PetscCall(PetscMalloc1(PetscMax(numLeaves, 0), &neighbors[comp]));
516:     /* I know this is p^2 time in general, but for bounded degree its alright */
517:     for (PetscInt l = 0; l < numLeaves; ++l) {
518:       const PetscInt face = lpoints ? lpoints[l] : l;

520:       /* Find a representative face (edge) separating pairs of procs */
521:       if ((face >= fStart) && (face < fEnd) && (faceComp[face - fStart] == comp) && rorntComp[face].rank) {
522:         const PetscInt rrank = rpoints[l].rank;
523:         const PetscInt rcomp = lorntComp[face].index;

525:         for (n = 0; n < numNeighbors[comp]; ++n)
526:           if ((rrank == rpoints[neighbors[comp][n]].rank) && (rcomp == lorntComp[lpoints[neighbors[comp][n]]].index)) break;
527:         if (n >= numNeighbors[comp]) {
528:           PetscInt supportSize;

530:           PetscCall(DMPlexGetSupportSize(dm, face, &supportSize));
531:           // We can have internal faces in the SF if we have cells in the SF
532:           if (supportSize > 1) continue;
533:           if (flg)
534:             PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]: component %d, Found representative leaf %" PetscInt_FMT " (face %" PetscInt_FMT ") connecting to face %" PetscInt_FMT " on (%" PetscInt_FMT ", %" PetscInt_FMT ") with orientation %" PetscInt_FMT "\n", rank, comp, l, face,
535:                                              rpoints[l].index, rrank, rcomp, lorntComp[face].rank));
536:           neighbors[comp][numNeighbors[comp]++] = l;
537:         }
538:       }
539:     }
540:     totNeighbors += numNeighbors[comp];
541:   }
542:   PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
543:   if (flg2) PetscCall(PetscViewerASCIIPopSynchronized(viewer));
544:   PetscCall(PetscMalloc2(totNeighbors, &nrankComp, totNeighbors, &match));
545:   for (comp = 0, off = 0; comp < numComponents; ++comp) {
546:     PetscInt n;

548:     for (n = 0; n < numNeighbors[comp]; ++n, ++off) {
549:       const PetscInt face = lpoints ? lpoints[neighbors[comp][n]] : neighbors[comp][n];
550:       const PetscInt o    = rorntComp[face].rank * lorntComp[face].rank;

552:       if (o < 0) match[off] = PETSC_TRUE;
553:       else if (o > 0) match[off] = PETSC_FALSE;
554:       else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid face %" PetscInt_FMT " (%" PetscInt_FMT ", %" PetscInt_FMT ") neighbor: %" PetscInt_FMT " comp: %d", face, rorntComp[face].rank, lorntComp[face].rank, neighbors[comp][n], comp);
555:       nrankComp[off].rank  = rpoints[neighbors[comp][n]].rank;
556:       nrankComp[off].index = lorntComp[lpoints ? lpoints[neighbors[comp][n]] : neighbors[comp][n]].index;
557:     }
558:     PetscCall(PetscFree(neighbors[comp]));
559:   }
560:   /* Collect the graph on 0 */
561:   if (numLeaves >= 0) {
562:     Mat          G;
563:     PetscBT      seenProcs, flippedProcs;
564:     PetscInt    *procFIFO, pTop, pBottom;
565:     PetscInt    *N          = NULL, *Noff;
566:     PetscSFNode *adj        = NULL;
567:     PetscBool   *val        = NULL;
568:     PetscMPIInt *recvcounts = NULL, *displs = NULL, *Nc, p, o, itotNeighbors;
569:     PetscMPIInt  size = 0;

571:     PetscCall(PetscCalloc1(numComponents, &flipped));
572:     if (rank == 0) PetscCallMPI(MPI_Comm_size(comm, &size));
573:     PetscCall(PetscCalloc4(size, &recvcounts, size + 1, &displs, size, &Nc, size + 1, &Noff));
574:     PetscCallMPI(MPI_Gather(&numComponents, 1, MPI_INT, Nc, 1, MPI_INT, 0, comm));
575:     for (p = 0; p < size; ++p) displs[p + 1] = displs[p] + Nc[p];
576:     if (rank == 0) PetscCall(PetscMalloc1(displs[size], &N));
577:     PetscCallMPI(MPI_Gatherv(numNeighbors, numComponents, MPIU_INT, N, Nc, displs, MPIU_INT, 0, comm));
578:     for (p = 0, o = 0; p < size; ++p) {
579:       recvcounts[p] = 0;
580:       for (c = 0; c < Nc[p]; ++c, ++o) recvcounts[p] += N[o];
581:       displs[p + 1] = displs[p] + recvcounts[p];
582:     }
583:     if (rank == 0) PetscCall(PetscMalloc2(displs[size], &adj, displs[size], &val));
584:     PetscCall(PetscMPIIntCast(totNeighbors, &itotNeighbors));
585:     PetscCallMPI(MPI_Gatherv(nrankComp, itotNeighbors, MPIU_SF_NODE, adj, recvcounts, displs, MPIU_SF_NODE, 0, comm));
586:     PetscCallMPI(MPI_Gatherv(match, itotNeighbors, MPI_C_BOOL, val, recvcounts, displs, MPI_C_BOOL, 0, comm));
587:     PetscCall(PetscFree2(numNeighbors, neighbors));
588:     if (rank == 0) {
589:       for (p = 1; p <= size; ++p) Noff[p] = Noff[p - 1] + Nc[p - 1];
590:       if (flg) {
591:         PetscInt n;

593:         for (p = 0, off = 0; p < size; ++p) {
594:           for (c = 0; c < Nc[p]; ++c) {
595:             PetscCall(PetscPrintf(PETSC_COMM_SELF, "Proc %d Comp %" PetscInt_FMT ":\n", p, c));
596:             for (n = 0; n < N[Noff[p] + c]; ++n, ++off) PetscCall(PetscPrintf(PETSC_COMM_SELF, "  edge (%" PetscInt_FMT ", %" PetscInt_FMT ") (%s):\n", adj[off].rank, adj[off].index, PetscBools[val[off]]));
597:           }
598:         }
599:       }
600:       /* Symmetrize the graph */
601:       PetscCall(MatCreate(PETSC_COMM_SELF, &G));
602:       PetscCall(MatSetSizes(G, Noff[size], Noff[size], Noff[size], Noff[size]));
603:       PetscCall(MatSetUp(G));
604:       for (p = 0, off = 0; p < size; ++p) {
605:         for (c = 0; c < Nc[p]; ++c) {
606:           const PetscInt r = Noff[p] + c;

608:           for (PetscInt n = 0; n < N[r]; ++n, ++off) {
609:             const PetscInt    q = Noff[adj[off].rank] + adj[off].index;
610:             const PetscScalar o = val[off] ? 1.0 : 0.0;

612:             PetscCall(MatSetValues(G, 1, &r, 1, &q, &o, INSERT_VALUES));
613:             PetscCall(MatSetValues(G, 1, &q, 1, &r, &o, INSERT_VALUES));
614:           }
615:         }
616:       }
617:       PetscCall(MatAssemblyBegin(G, MAT_FINAL_ASSEMBLY));
618:       PetscCall(MatAssemblyEnd(G, MAT_FINAL_ASSEMBLY));

620:       PetscCall(PetscBTCreate(Noff[size], &seenProcs));
621:       PetscCall(PetscBTMemzero(Noff[size], seenProcs));
622:       PetscCall(PetscBTCreate(Noff[size], &flippedProcs));
623:       PetscCall(PetscBTMemzero(Noff[size], flippedProcs));
624:       PetscCall(PetscMalloc1(Noff[size], &procFIFO));
625:       pTop = pBottom = 0;
626:       for (p = 0; p < Noff[size]; ++p) {
627:         if (PetscBTLookup(seenProcs, p)) continue;
628:         /* Initialize FIFO with next proc */
629:         procFIFO[pBottom++] = p;
630:         PetscCall(PetscBTSet(seenProcs, p));
631:         /* Consider each proc in FIFO */
632:         while (pTop < pBottom) {
633:           const PetscScalar *ornt;
634:           const PetscInt    *neighbors;
635:           PetscInt           proc, nproc, seen, flippedA, flippedB, mismatch, numNeighbors, n;

637:           proc     = procFIFO[pTop++];
638:           flippedA = PetscBTLookup(flippedProcs, proc) ? 1 : 0;
639:           PetscCall(MatGetRow(G, proc, &numNeighbors, &neighbors, &ornt));
640:           /* Loop over neighboring procs */
641:           for (n = 0; n < numNeighbors; ++n) {
642:             nproc    = neighbors[n];
643:             mismatch = PetscRealPart(ornt[n]) > 0.5 ? 0 : 1;
644:             seen     = PetscBTLookup(seenProcs, nproc);
645:             flippedB = PetscBTLookup(flippedProcs, nproc) ? 1 : 0;

647:             if (mismatch ^ (flippedA ^ flippedB)) {
648:               PetscCheck(!seen, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Previously seen procs %" PetscInt_FMT " and %" PetscInt_FMT " do not match: Fault mesh is non-orientable", proc, nproc);
649:               PetscCheck(!flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Inconsistent mesh orientation: Fault mesh is non-orientable");
650:               PetscCall(PetscBTSet(flippedProcs, nproc));
651:             } else PetscCheck(!mismatch || !flippedA || !flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Attempt to flip already flipped cell: Fault mesh is non-orientable");
652:             if (!seen) {
653:               procFIFO[pBottom++] = nproc;
654:               PetscCall(PetscBTSet(seenProcs, nproc));
655:             }
656:           }
657:         }
658:       }
659:       PetscCall(PetscFree(procFIFO));
660:       PetscCall(MatDestroy(&G));
661:       PetscCall(PetscFree2(adj, val));
662:       PetscCall(PetscBTDestroy(&seenProcs));
663:     }
664:     /* Scatter flip flags */
665:     {
666:       PetscBool *flips = NULL;

668:       if (rank == 0) {
669:         PetscCall(PetscMalloc1(Noff[size], &flips));
670:         for (p = 0; p < Noff[size]; ++p) {
671:           flips[p] = PetscBTLookup(flippedProcs, p) ? PETSC_TRUE : PETSC_FALSE;
672:           if (flg && flips[p]) PetscCall(PetscPrintf(comm, "Flipping Proc+Comp %d:\n", p));
673:         }
674:         for (p = 0; p < size; ++p) displs[p + 1] = displs[p] + Nc[p];
675:       }
676:       PetscCallMPI(MPI_Scatterv(flips, Nc, displs, MPI_C_BOOL, flipped, numComponents, MPI_C_BOOL, 0, comm));
677:       PetscCall(PetscFree(flips));
678:     }
679:     if (rank == 0) PetscCall(PetscBTDestroy(&flippedProcs));
680:     PetscCall(PetscFree(N));
681:     PetscCall(PetscFree4(recvcounts, displs, Nc, Noff));
682:     PetscCall(PetscFree2(nrankComp, match));

684:     /* Decide whether to flip cells in each component */
685:     for (c = 0; c < cEnd - cStart; ++c) {
686:       if (flipped[cellComp[c]]) PetscCall(PetscBTNegate(flippedCells, c));
687:     }
688:     PetscCall(PetscFree(flipped));
689:   }
690:   if (flg) {
691:     PetscViewer v;

693:     PetscCall(PetscViewerASCIIGetStdout(comm, &v));
694:     PetscCall(PetscViewerASCIIPushSynchronized(v));
695:     PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]BT for parallel flipped cells:\n", rank));
696:     PetscCall(PetscBTView(cEnd - cStart, flippedCells, v));
697:     PetscCall(PetscViewerFlush(v));
698:     PetscCall(PetscViewerASCIIPopSynchronized(v));
699:   }
700:   /* Reverse flipped cells in the mesh */
701:   for (c = cStart; c < cEnd; ++c) {
702:     if (PetscBTLookup(flippedCells, c - cStart)) PetscCall(DMPlexOrientPoint(dm, c, -1));
703:   }
704:   PetscCall(PetscBTDestroy(&seenCells));
705:   PetscCall(PetscBTDestroy(&flippedCells));
706:   PetscCall(PetscBTDestroy(&seenFaces));
707:   PetscCall(PetscFree2(numNeighbors, neighbors));
708:   PetscCall(PetscFree3(rorntComp, lorntComp, locSupport));
709:   PetscCall(PetscFree3(faceFIFO, cellComp, faceComp));
710:   PetscFunctionReturn(PETSC_SUCCESS);
711: #endif
712: }

714: static PetscErrorCode CreateCellAndFaceIS_Private(DM dm, DMLabel label, IS *cellIS, IS *faceIS)
715: {
716:   IS              valueIS;
717:   const PetscInt *values;
718:   PetscInt        Nv, depth = 0;

720:   PetscFunctionBegin;
721:   PetscCall(DMLabelGetValueIS(label, &valueIS));
722:   PetscCall(ISGetLocalSize(valueIS, &Nv));
723:   PetscCall(ISGetIndices(valueIS, &values));
724:   for (PetscInt v = 0; v < Nv; ++v) {
725:     const PetscInt val = values[v] < 0 || values[v] >= 100 ? 0 : values[v];
726:     PetscInt       n;

728:     PetscCall(DMLabelGetStratumSize(label, val, &n));
729:     if (!n) continue;
730:     depth = PetscMax(val, depth);
731:   }
732:   PetscCall(ISDestroy(&valueIS));
733:   PetscCheck(depth >= 1 || !Nv, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Depth for interface must be at least 1, not %" PetscInt_FMT, depth);
734:   PetscCall(DMLabelGetStratumIS(label, depth, cellIS));
735:   PetscCall(DMLabelGetStratumIS(label, depth - 1, faceIS));
736:   if (!*cellIS) PetscCall(ISCreateStride(PETSC_COMM_SELF, 0, 0, 1, cellIS));
737:   if (!*faceIS) PetscCall(ISCreateStride(PETSC_COMM_SELF, 0, 0, 1, faceIS));
738:   PetscFunctionReturn(PETSC_SUCCESS);
739: }

741: PetscErrorCode DMPlexOrientLabel(DM dm, DMLabel label)
742: {
743:   IS cellIS, faceIS;

745:   PetscFunctionBegin;
746:   PetscCall(CreateCellAndFaceIS_Private(dm, label, &cellIS, &faceIS));
747:   PetscCall(DMPlexOrientCells_Internal(dm, cellIS, faceIS));
748:   PetscCall(ISDestroy(&cellIS));
749:   PetscCall(ISDestroy(&faceIS));
750:   PetscFunctionReturn(PETSC_SUCCESS);
751: }

753: typedef struct {
754:   PetscInt comp; // connected component number
755:   PetscInt cell; // cell determining face orientation
756:   PetscInt ornt; // face orientation
757: } SharedFace;

759: static PetscErrorCode DMPlexOrientCreateSharedFaces_Internal(DM dm, IS cellIS, IS faceIS, PetscInt Ncomp, const PetscInt faceComp[], PetscBT cellFlip, SharedFace **localFace, SharedFace **remoteFace)
760: {
761:   const PetscInt     debug = ((DM_Plex *)dm->data)->printOrient;
762:   const PetscInt    *cells = NULL, *faces = NULL;
763:   PetscInt           cStart = 0, cEnd = 0, fStart = 0, fEnd = 0;
764:   PetscSF            sf;
765:   const PetscInt    *lpoints, *rootdegree;
766:   const PetscSFNode *rpoints;
767:   PetscInt           Nr, Nl;
768:   PetscInt           depth, fdepth;
769:   PetscBool          faceIsVertex = PETSC_FALSE;
770:   MPI_Datatype       MPIU_3INT;
771:   PetscViewer        viewer = NULL, selfviewer = NULL;
772:   PetscMPIInt        rank;

774:   PetscFunctionBegin;
775:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank));
776:   PetscCall(DMPlexGetDepth(dm, &depth));
777:   PetscCall(DMGetPointSF(dm, &sf));
778:   PetscCall(PetscSFGetGraph(sf, &Nr, &Nl, &lpoints, &rpoints));
779:   PetscCall(PetscSFComputeDegreeBegin(sf, &rootdegree));
780:   PetscCall(PetscSFComputeDegreeEnd(sf, &rootdegree));
781:   PetscCall(PetscMalloc2(Nr, localFace, Nr, remoteFace));
782:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
783:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
784:   PetscCall(DMPlexGetPointDepth(dm, faces ? faces[fStart] : fStart, &fdepth));
785:   if (!fdepth) faceIsVertex = PETSC_TRUE;
786:   for (PetscInt r = 0; r < Nr; ++r) {
787:     (*localFace)[r].comp  = -1;
788:     (*remoteFace)[r].comp = -1;
789:   }
790:   // Get information for shared faces
791:   if (debug) {
792:     viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)dm));
793:     PetscCall(PetscViewerASCIIPushSynchronized(viewer));
794:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
795:   }
796:   for (PetscInt f = fStart; f < fEnd; ++f) {
797:     const PetscInt  face = faces ? faces[f] : f;
798:     const PetscInt *supp, *cone, *ornt;
799:     PetscInt        lf, sS, cS, cind = -1, c;

801:     (*localFace)[face].comp = -1;
802:     (*localFace)[face].cell = -1;
803:     (*localFace)[face].ornt = 0;
804:     PetscCall(PetscFindInt(face, Nl, lpoints, &lf));
805:     if (!rootdegree[face] && lf < 0) continue;
806:     PetscCall(DMPlexGetSupportSize(dm, face, &sS));
807:     PetscCall(DMPlexGetSupport(dm, face, &supp));
808:     for (PetscInt s = 0; s < sS; ++s) {
809:       PetscInt pdepth, l;

811:       // Filter support
812:       cind = GetPointIndex(supp[s], cStart, cEnd, cells);
813:       if (cind < 0) continue;
814:       // Ignore overlapping cells, but not for embedded manifolds
815:       PetscCall(DMPlexGetPointDepth(dm, supp[s], &pdepth));
816:       PetscCall(PetscFindInt(supp[s], Nl, lpoints, &l));
817:       if (pdepth == depth && l >= 0) continue;
818:       (*localFace)[face].cell = supp[s];
819:       break;
820:     }
821:     (*localFace)[face].comp = faceComp[f - fStart];
822:     // Cannot determine orientation without a cell
823:     if (cind < 0) continue;
824:     PetscCheck(0 <= faceComp[f - fStart] && faceComp[f - fStart] < Ncomp, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid component %" PetscInt_FMT " for face %" PetscInt_FMT " (%" PetscInt_FMT ")", faceComp[f - fStart], face, f);
825:     PetscCall(DMPlexGetOrientedCone(dm, (*localFace)[face].cell, &cone, &ornt));
826:     PetscCall(DMPlexGetConeSize(dm, (*localFace)[face].cell, &cS));
827:     for (c = 0; c < cS; ++c)
828:       if (cone[c] == face) break;
829:     PetscCheck(c < cS, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " not found in cone of cell %" PetscInt_FMT, face, (*localFace)[face].cell);
830:     if (faceIsVertex) {
831:       // Use cone position, shifted to -1 or 1
832:       if (PetscBTLookup(cellFlip, cind)) (*localFace)[face].ornt = 1 - c * 2;
833:       else (*localFace)[face].ornt = c * 2 - 1;
834:     } else {
835:       // Use orientation sense
836:       if (PetscBTLookup(cellFlip, cind)) (*localFace)[face].ornt = ornt[c] < 0 ? -1 : 1;
837:       else (*localFace)[face].ornt = ornt[c] < 0 ? 1 : -1;
838:     }
839:     PetscCall(DMPlexRestoreOrientedCone(dm, (*localFace)[face].cell, &cone, &ornt));
840:     if (debug)
841:       PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]: Local shared face %" PetscInt_FMT " component %" PetscInt_FMT " cell %" PetscInt_FMT " orientation %" PetscInt_FMT "\n", rank, face, (*localFace)[face].comp, (*localFace)[face].cell,
842:                                        (*localFace)[face].ornt));
843:   }
844:   if (debug) {
845:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
846:     PetscCall(PetscViewerASCIIPopSynchronized(viewer));
847:   }
848:   // Get information from owners
849:   PetscCallMPI(MPI_Type_contiguous(3, MPIU_INT, &MPIU_3INT));
850:   PetscCallMPI(MPI_Type_commit(&MPIU_3INT));
851:   PetscCall(PetscSFBcastBegin(sf, MPIU_3INT, *localFace, *remoteFace, MPI_REPLACE));
852:   PetscCall(PetscSFBcastEnd(sf, MPIU_3INT, *localFace, *remoteFace, MPI_REPLACE));
853:   PetscCallMPI(MPI_Type_free(&MPIU_3INT));
854:   PetscFunctionReturn(PETSC_SUCCESS);
855: }

857: typedef struct {
858:   PetscInt lface; // local shared face
859:   PetscInt lcell; // local cell determining face orientation
860:   PetscInt lornt; // local face orientation
861:   PetscInt rrank; // remote rank
862:   PetscInt rcomp; // remote connected component
863:   PetscInt rface; // remote shared face
864:   PetscInt rcell; // remote cell determining face orientation
865:   PetscInt rornt; // remote face orientation
866: } Neighbor;

868: static PetscErrorCode DMPlexOrientCreateNeighbors_Internal(DM dm, IS cellIS, IS faceIS, PetscInt Ncomp, const PetscInt faceComp[], const SharedFace localFace[], const SharedFace remoteFace[], PetscInt **Nneigh, Neighbor ***neighbors)
869: {
870:   const PetscInt     debug = ((DM_Plex *)dm->data)->printOrient;
871:   const PetscInt    *cells = NULL, *faces = NULL;
872:   PetscInt           cStart = 0, cEnd = 0, fStart = 0, fEnd = 0;
873:   PetscSF            sf;
874:   const PetscInt    *lpoints;
875:   const PetscSFNode *rpoints;
876:   PetscInt           Nl;
877:   PetscHSetIJ       *ht;
878:   PetscInt          *counts;
879:   PetscViewer        viewer = NULL, selfviewer = NULL;
880:   PetscMPIInt        rank;

882:   PetscFunctionBegin;
883:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank));
884:   if (debug) {
885:     viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)dm));
886:     PetscCall(PetscViewerASCIIPushSynchronized(viewer));
887:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
888:   }
889:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
890:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
891:   PetscCall(DMGetPointSF(dm, &sf));
892:   PetscCall(PetscSFGetGraph(sf, NULL, &Nl, &lpoints, &rpoints));
893:   PetscCall(PetscCalloc2(Ncomp, &ht, Ncomp, &counts));
894:   for (PetscInt c = 0; c < Ncomp; ++c) PetscCall(PetscHSetIJCreate(&ht[c]));
895:   PetscCall(PetscCalloc2(Ncomp, Nneigh, Ncomp, neighbors));
896:   // Count the number of unique connections between process/component
897:   for (PetscInt f = fStart; f < fEnd; ++f) {
898:     const PetscInt face = faces ? faces[f] : f;
899:     PetscHashIJKey key;
900:     PetscInt       l;

902:     PetscCall(PetscFindInt(face, Nl, lpoints, &l));
903:     if (l < 0) continue;
904:     // Remote face is not part of the label
905:     if (remoteFace[face].comp < 0) continue;
906:     // Remote face is isolated from any surface cell, so cannot get orientation
907:     if (!remoteFace[face].ornt) continue;
908:     key.i = rpoints[l].rank;
909:     key.j = remoteFace[face].comp;
910:     PetscCheck(0 <= remoteFace[face].comp, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid component %" PetscInt_FMT " on remote face %" PetscInt_FMT " from rank %" PetscInt_FMT " for local face %" PetscInt_FMT, remoteFace[face].comp, rpoints[l].index,
911:                rpoints[l].rank, face);
912:     PetscCall(PetscHSetIJAdd(ht[faceComp[f - fStart]], key));
913:   }
914:   // Get the sizes from each hash
915:   for (PetscInt c = 0; c < Ncomp; ++c) {
916:     PetscCall(PetscHSetIJGetSize(ht[c], &(*Nneigh)[c]));
917:     PetscCall(PetscMalloc1((*Nneigh)[c], &(*neighbors)[c]));
918:     PetscCall(PetscHSetIJClear(ht[c]));
919:     if (debug) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]: component %" PetscInt_FMT ", Found %" PetscInt_FMT " connections\n", rank, c, (*Nneigh)[c]));
920:   }
921:   // Gather the neighbor information
922:   for (PetscInt f = fStart; f < fEnd; ++f) {
923:     const PetscInt face = faces ? faces[f] : f;
924:     const PetscInt comp = faceComp[f - fStart];
925:     const PetscInt ind  = counts[comp];
926:     PetscHashIJKey key;
927:     PetscBool      missing;
928:     PetscInt       l;

930:     PetscCheck(0 <= comp && comp < Ncomp, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid component %" PetscInt_FMT, comp);
931:     PetscCall(PetscFindInt(face, Nl, lpoints, &l));
932:     if (l < 0) continue;
933:     if (remoteFace[face].comp < 0) continue;
934:     if (!remoteFace[face].ornt) continue;
935:     key.i = rpoints[l].rank;
936:     key.j = remoteFace[face].comp;
937:     PetscCall(PetscHSetIJQueryAdd(ht[comp], key, &missing));
938:     if (!missing) continue;
939:     PetscCheck(localFace[face].ornt != 0, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid local face %" PetscInt_FMT " orientation: %" PetscInt_FMT, face, localFace[face].ornt);
940:     (*neighbors)[comp][ind].lface = face;
941:     (*neighbors)[comp][ind].lcell = localFace[face].cell;
942:     (*neighbors)[comp][ind].lornt = localFace[face].ornt;
943:     (*neighbors)[comp][ind].rrank = rpoints[l].rank;
944:     (*neighbors)[comp][ind].rcomp = remoteFace[face].comp;
945:     (*neighbors)[comp][ind].rface = rpoints[l].index;
946:     (*neighbors)[comp][ind].rcell = remoteFace[face].cell;
947:     (*neighbors)[comp][ind].rornt = remoteFace[face].ornt;
948:     if (debug)
949:       PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]: component %" PetscInt_FMT ", Found representative %" PetscInt_FMT " leaf %" PetscInt_FMT " (face %" PetscInt_FMT ") connecting to face %" PetscInt_FMT " on (%" PetscInt_FMT ", %" PetscInt_FMT ", %" PetscInt_FMT ") with orientation %" PetscInt_FMT "\n", rank,
950:                                        remoteFace[face].comp, ind, l, face, (*neighbors)[comp][ind].rface, (*neighbors)[comp][ind].rrank, (*neighbors)[comp][ind].rcomp, (*neighbors)[comp][ind].rcell, (*neighbors)[comp][ind].rornt));
951:     ++counts[comp];
952:   }
953:   // Cleanup
954:   if (debug) {
955:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
956:     PetscCall(PetscViewerASCIIPopSynchronized(viewer));
957:   }
958:   for (PetscInt c = 0; c < Ncomp; ++c) {
959:     PetscCheck(counts[c] == (*Nneigh)[c], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Neigh count for component %" PetscInt_FMT ": %" PetscInt_FMT " != %" PetscInt_FMT " allocated size", c, counts[c], (*Nneigh)[c]);
960:     PetscCall(PetscHSetIJDestroy(&ht[c]));
961:   }
962:   PetscCall(PetscFree2(ht, counts));
963:   PetscFunctionReturn(PETSC_SUCCESS);
964: }

966: static PetscErrorCode DMPlexOrientCreateProcessGraph_Internal(DM dm, IS faceIS, PetscInt Ncomp, const PetscInt Nneigh[], Neighbor *neighbors[], PetscSFNode **neighborAdj, PetscBool **neighborVal)
967: {
968:   const PetscInt    *faces  = NULL;
969:   PetscInt           fStart = 0, fEnd = 0;
970:   PetscSFNode       *nrankComp; // The (rank, comp) of each neighbor
971:   PetscBool         *match;     // Whether neighbors currently match
972:   PetscSF            sf;
973:   const PetscInt    *lpoints;
974:   const PetscSFNode *rpoints;
975:   PetscInt           totNeighbors = 0, Nl, fdepth;
976:   PetscBool          faceIsVertex = PETSC_FALSE;

978:   PetscFunctionBegin;
979:   PetscCall(DMGetPointSF(dm, &sf));
980:   PetscCall(PetscSFGetGraph(sf, NULL, &Nl, &lpoints, &rpoints));
981:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
982:   PetscCall(DMPlexGetPointDepth(dm, faces ? faces[fStart] : fStart, &fdepth));
983:   if (!fdepth) faceIsVertex = PETSC_TRUE;
984:   for (PetscInt c = 0; c < Ncomp; ++c) totNeighbors += Nneigh[c];
985:   PetscCall(PetscMalloc2(totNeighbors, neighborAdj, totNeighbors, neighborVal));
986:   nrankComp = *neighborAdj;
987:   match     = *neighborVal;
988:   for (PetscInt c = 0, off = 0; c < Ncomp; ++c) {
989:     for (PetscInt n = 0; n < Nneigh[c]; ++n, ++off) {
990:       PetscInt l;

992:       if (faceIsVertex) {
993:         match[off] = neighbors[c][n].lornt != neighbors[c][n].rornt ? PETSC_TRUE : PETSC_FALSE;
994:       } else {
995:         const PetscInt o = neighbors[c][n].lornt * neighbors[c][n].rornt;

997:         if (o < 0) match[off] = PETSC_TRUE;
998:         else match[off] = PETSC_FALSE;
999:       }
1000:       // Flip sense if we are matching from an unowned cell
1001:       PetscCall(PetscFindInt(neighbors[c][n].lcell, Nl, lpoints, &l));
1002:       if (l >= 0) {
1003:         if (rpoints[l].rank == neighbors[c][n].rrank && rpoints[l].index == neighbors[c][n].rcell) match[off] = match[off] ? PETSC_FALSE : PETSC_TRUE;
1004:       }
1005:       nrankComp[off].rank  = neighbors[c][n].rrank;
1006:       nrankComp[off].index = neighbors[c][n].rcomp;
1007:     }
1008:   }
1009:   PetscFunctionReturn(PETSC_SUCCESS);
1010: }

1012: static PetscErrorCode DMPlexOrientSolveProcessGraph_Internal(DM dm, IS cellIS, PetscInt Ncomp, const PetscInt cellComp[], const PetscInt Nneigh[], const PetscSFNode nrankComp[], const PetscBool match[], PetscBT cellFlip)
1013: {
1014:   const PetscInt     debug  = ((DM_Plex *)dm->data)->printOrient;
1015:   const PetscInt    *cells  = NULL;
1016:   PetscInt           cStart = 0, cEnd = 0;
1017:   PetscSF            sf;
1018:   const PetscInt    *lpoints;
1019:   const PetscSFNode *rpoints;
1020:   PetscInt           Nl, totNeighbors = 0;
1021:   PetscBool         *flipped;
1022:   MPI_Comm           comm;
1023:   PetscMPIInt        rank;

1025:   PetscFunctionBegin;
1026:   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
1027:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
1028:   PetscCall(DMGetPointSF(dm, &sf));
1029:   PetscCall(PetscSFGetGraph(sf, NULL, &Nl, &lpoints, &rpoints));
1030:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
1031:   /* Collect the graph on 0 */
1032:   for (PetscInt c = 0; c < Ncomp; ++c) totNeighbors += Nneigh[c];
1033:   if (Nl >= 0) {
1034:     Mat          G;
1035:     PetscBT      seenProcs, flippedProcs;
1036:     PetscInt    *procFIFO, pTop, pBottom;
1037:     PetscInt    *N          = NULL, *Noff;
1038:     PetscSFNode *adj        = NULL;
1039:     PetscBool   *val        = NULL;
1040:     PetscMPIInt *recvcounts = NULL, *displs = NULL, *Nc;
1041:     PetscMPIInt  size = 0, iNcomp, itotNeighbors;

1043:     PetscCall(PetscCalloc1(Ncomp, &flipped));
1044:     if (rank == 0) PetscCallMPI(MPI_Comm_size(comm, &size));
1045:     PetscCall(PetscCalloc4(size, &recvcounts, size + 1, &displs, size, &Nc, size + 1, &Noff));
1046:     PetscCallMPI(MPI_Gather(&Ncomp, 1, MPI_INT, Nc, 1, MPI_INT, 0, comm));
1047:     for (PetscInt p = 0; p < size; ++p) displs[p + 1] = displs[p] + Nc[p];
1048:     if (rank == 0) PetscCall(PetscMalloc1(displs[size], &N));
1049:     PetscCall(PetscMPIIntCast(Ncomp, &iNcomp));
1050:     PetscCallMPI(MPI_Gatherv(Nneigh, iNcomp, MPIU_INT, N, Nc, displs, MPIU_INT, 0, comm));
1051:     for (PetscInt p = 0, o = 0; p < size; ++p) {
1052:       recvcounts[p] = 0;
1053:       for (PetscInt c = 0; c < Nc[p]; ++c, ++o) recvcounts[p] += N[o];
1054:       displs[p + 1] = displs[p] + recvcounts[p];
1055:     }
1056:     if (rank == 0) PetscCall(PetscMalloc2(displs[size], &adj, displs[size], &val));
1057:     PetscCall(PetscMPIIntCast(totNeighbors, &itotNeighbors));
1058:     PetscCallMPI(MPI_Gatherv(nrankComp, itotNeighbors, MPIU_SF_NODE, adj, recvcounts, displs, MPIU_SF_NODE, 0, comm));
1059:     PetscCallMPI(MPI_Gatherv(match, itotNeighbors, MPI_C_BOOL, val, recvcounts, displs, MPI_C_BOOL, 0, comm));
1060:     if (rank == 0) {
1061:       for (PetscInt p = 1; p <= size; ++p) Noff[p] = Noff[p - 1] + Nc[p - 1];
1062:       if (debug) {
1063:         for (PetscInt p = 0, off = 0; p < size; ++p) {
1064:           for (PetscInt c = 0; c < Nc[p]; ++c) {
1065:             PetscCall(PetscPrintf(PETSC_COMM_SELF, "Proc %" PetscInt_FMT " Comp %" PetscInt_FMT ":\n", p, c));
1066:             for (PetscInt n = 0; n < N[Noff[p] + c]; ++n, ++off) PetscCall(PetscPrintf(PETSC_COMM_SELF, "  edge (%" PetscInt_FMT ", %" PetscInt_FMT ") (%s):\n", adj[off].rank, adj[off].index, PetscBools[val[off]]));
1067:           }
1068:         }
1069:       }
1070:       /* Symmetrize the graph */
1071:       PetscCall(MatCreate(PETSC_COMM_SELF, &G));
1072:       PetscCall(MatSetSizes(G, Noff[size], Noff[size], Noff[size], Noff[size]));
1073:       PetscCall(MatSetUp(G));
1074:       for (PetscInt p = 0, off = 0; p < size; ++p) {
1075:         for (PetscInt c = 0; c < Nc[p]; ++c) {
1076:           const PetscInt r = Noff[p] + c;

1078:           for (PetscInt n = 0; n < N[r]; ++n, ++off) {
1079:             const PetscInt    q = Noff[adj[off].rank] + adj[off].index;
1080:             const PetscScalar o = val[off] ? 1.0 : 0.0;

1082:             // Do not set values for processes that have no face to orient
1083:             if (!Nc[adj[off].rank]) continue;
1084:             PetscCall(MatSetValues(G, 1, &r, 1, &q, &o, INSERT_VALUES));
1085:             PetscCall(MatSetValues(G, 1, &q, 1, &r, &o, INSERT_VALUES));
1086:           }
1087:         }
1088:       }
1089:       PetscCall(MatAssemblyBegin(G, MAT_FINAL_ASSEMBLY));
1090:       PetscCall(MatAssemblyEnd(G, MAT_FINAL_ASSEMBLY));

1092:       PetscCall(PetscBTCreate(Noff[size], &seenProcs));
1093:       PetscCall(PetscBTMemzero(Noff[size], seenProcs));
1094:       PetscCall(PetscBTCreate(Noff[size], &flippedProcs));
1095:       PetscCall(PetscBTMemzero(Noff[size], flippedProcs));
1096:       PetscCall(PetscMalloc1(Noff[size], &procFIFO));
1097:       pTop = pBottom = 0;
1098:       for (PetscInt p = 0; p < Noff[size]; ++p) {
1099:         if (PetscBTLookup(seenProcs, p)) continue;
1100:         /* Initialize FIFO with next proc */
1101:         procFIFO[pBottom++] = p;
1102:         PetscCall(PetscBTSet(seenProcs, p));
1103:         /* Consider each proc in FIFO */
1104:         while (pTop < pBottom) {
1105:           const PetscScalar *ornt;
1106:           const PetscInt    *neighbors;
1107:           PetscInt           proc, nproc, seen, flippedA, flippedB, mismatch, numNeighbors;

1109:           proc     = procFIFO[pTop++];
1110:           flippedA = PetscBTLookup(flippedProcs, proc) ? 1 : 0;
1111:           PetscCall(MatGetRow(G, proc, &numNeighbors, &neighbors, &ornt));
1112:           /* Loop over neighboring procs */
1113:           for (PetscInt n = 0; n < numNeighbors; ++n) {
1114:             nproc    = neighbors[n];
1115:             mismatch = PetscRealPart(ornt[n]) > 0.5 ? 0 : 1;
1116:             seen     = PetscBTLookup(seenProcs, nproc);
1117:             flippedB = PetscBTLookup(flippedProcs, nproc) ? 1 : 0;

1119:             if (mismatch ^ (flippedA ^ flippedB)) {
1120:               PetscCheck(!seen, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Previously seen procs %" PetscInt_FMT " and %" PetscInt_FMT " do not match: Fault mesh is non-orientable", proc, nproc);
1121:               PetscCheck(!flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Inconsistent mesh orientation: Fault mesh is non-orientable");
1122:               PetscCall(PetscBTSet(flippedProcs, nproc));
1123:             } else PetscCheck(!mismatch || !flippedA || !flippedB, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Attempt to flip already flipped cell: Fault mesh is non-orientable");
1124:             if (!seen) {
1125:               procFIFO[pBottom++] = nproc;
1126:               PetscCall(PetscBTSet(seenProcs, nproc));
1127:             }
1128:           }
1129:         }
1130:       }
1131:       PetscCall(PetscFree(procFIFO));
1132:       PetscCall(MatDestroy(&G));
1133:       PetscCall(PetscFree2(adj, val));
1134:       PetscCall(PetscBTDestroy(&seenProcs));
1135:     }
1136:     /* Scatter flip flags */
1137:     {
1138:       PetscBool *flips = NULL;

1140:       if (rank == 0) {
1141:         PetscCall(PetscMalloc1(Noff[size], &flips));
1142:         for (PetscInt p = 0; p < Noff[size]; ++p) {
1143:           flips[p] = PetscBTLookup(flippedProcs, p) ? PETSC_TRUE : PETSC_FALSE;
1144:           if (debug && flips[p]) PetscCall(PetscPrintf(PETSC_COMM_SELF, "Flipping Proc+Comp %" PetscInt_FMT ":\n", p));
1145:         }
1146:         for (PetscInt p = 0; p < size; ++p) displs[p + 1] = displs[p] + Nc[p];
1147:       }
1148:       PetscCall(PetscMPIIntCast(Ncomp, &iNcomp));
1149:       PetscCallMPI(MPI_Scatterv(flips, Nc, displs, MPI_C_BOOL, flipped, iNcomp, MPI_C_BOOL, 0, comm));
1150:       PetscCall(PetscFree(flips));
1151:     }
1152:     if (rank == 0) PetscCall(PetscBTDestroy(&flippedProcs));
1153:     PetscCall(PetscFree(N));
1154:     PetscCall(PetscFree4(recvcounts, displs, Nc, Noff));

1156:     /* Decide whether to flip cells in each component */
1157:     for (PetscInt c = 0; c < cEnd - cStart; ++c) {
1158:       if (flipped[cellComp[c]]) PetscCall(PetscBTNegate(cellFlip, c));
1159:     }
1160:     PetscCall(PetscFree(flipped));
1161:   }
1162:   PetscFunctionReturn(PETSC_SUCCESS);
1163: }

1165: // Reverse flipped cells in the mesh
1166: static PetscErrorCode DMPlexOrientPlex_Internal(DM dm, IS cellIS, PetscBT cellFlip)
1167: {
1168:   const PetscInt  debug  = ((DM_Plex *)dm->data)->printOrient;
1169:   const PetscInt *cells  = NULL;
1170:   PetscInt        cStart = 0, cEnd = 0;
1171:   PetscSF         sf;
1172:   const PetscInt *rootdegree = NULL;
1173:   PetscInt       *points     = NULL;
1174:   PetscInt        pStart, pEnd, Nr, depth, cdepth = -1;
1175:   PetscViewer     v;
1176:   PetscMPIInt     rank;

1178:   PetscFunctionBegin;
1179:   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank));
1180:   if (debug) {
1181:     PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)dm), &v));
1182:     PetscCall(PetscViewerASCIIPushSynchronized(v));
1183:   }
1184:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
1185:   PetscCall(DMPlexGetDepth(dm, &depth));
1186:   if (cEnd > cStart) PetscCall(DMPlexGetPointDepth(dm, cells ? cells[cStart] : cStart, &cdepth));
1187:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &cdepth, 1, MPIU_INT, MPI_MAX, PetscObjectComm((PetscObject)dm)));
1188:   PetscCall(DMGetPointSF(dm, &sf));
1189:   PetscCall(PetscSFGetGraph(sf, &Nr, NULL, NULL, NULL));
1190:   if (Nr >= 0) {
1191:     PetscCall(PetscSFComputeDegreeBegin(sf, &rootdegree));
1192:     PetscCall(PetscSFComputeDegreeEnd(sf, &rootdegree));
1193:   }
1194:   PetscCall(DMPlexGetChart(dm, &pStart, &pEnd));
1195:   if (cdepth == depth) PetscCall(PetscCalloc1(pEnd - pStart, &points));
1196:   for (PetscInt c = cStart; c < cEnd; ++c) {
1197:     if (PetscBTLookup(cellFlip, c - cStart)) {
1198:       const PetscInt cell = cells ? cells[c] : c;

1200:       PetscCall(DMPlexOrientPoint(dm, cell, -1));
1201:       if (points && rootdegree && rootdegree[cell]) points[cell] = 1;
1202:       if (debug) PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]Flipping cell %" PetscInt_FMT "%s\n", rank, cell, points && rootdegree && rootdegree[cell] ? " and sending to overlap" : ""));
1203:     }
1204:   }
1205:   // Propagate flips for volumetric cells in the overlap
1206:   if (cdepth == depth) {
1207:     if (Nr >= 0) {
1208:       PetscCall(PetscSFBcastBegin(sf, MPIU_INT, points, points, MPI_SUM));
1209:       PetscCall(PetscSFBcastEnd(sf, MPIU_INT, points, points, MPI_SUM));
1210:     }
1211:     for (PetscInt c = cStart; c < cEnd; ++c) {
1212:       const PetscInt cell = cells ? cells[c] : c;

1214:       if (points[cell] && !PetscBTLookup(cellFlip, c - cStart)) {
1215:         PetscCall(DMPlexOrientPoint(dm, cell, -1));
1216:         if (debug) PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]Flipping cell %" PetscInt_FMT " through overlap\n", rank, cell));
1217:       }
1218:     }
1219:     PetscCall(PetscFree(points));
1220:   }
1221:   if (debug) {
1222:     PetscCall(PetscViewerFlush(v));
1223:     PetscCall(PetscViewerASCIIPopSynchronized(v));
1224:   }
1225:   PetscFunctionReturn(PETSC_SUCCESS);
1226: }

1228: /*
1229:   The orientation operation needs to perform two functions:

1231:   1) Orient a bulk mesh. Here we assume that faces are in the correct order, but may
1232:      be reversed.

1234:   2) Orient a manifold embedded in a given mesh. This introduces many complications, since
1235:      lower-dimensional pieces of the manifold might be shared with other processes.

1237:   We will divide the operation into phases

1239:   1) Each process orients the local mesh or manifold, and also counts the connected components.

1241:   2) Send information about all neighboring faces to leaves

1243:   3) Determine which processes are connected to each component, and pick a representative shared face connecting them

1245:      For volumetric meshes (ignoring overlap cells), shared faces connect a single cell on each process.

1247:      For manifolds, interior faces can be shared, so multiple cells can be connected. We must determine whether the cells
1248:      we are using to compute orientation are identified.

1250:   4) Determine whether the orientations match across each process boundary, to make the local piece of the process graph

1252:      For manifolds, if the assoicated cells are identified, we flip the sense of the comparison.

1254:   5) Gather the process graph to process 0, compute a satisfying orientation, communicate the orientation

1256:   6) Flip the relevant cells and for volumetric meshes, propagate reordering to overlap cells
1257: */
1258: PetscErrorCode DMPlexOrientCells_Internal(DM dm, IS cellIS, IS faceIS)
1259: {
1260:   const PetscInt  debug = ((DM_Plex *)dm->data)->printOrient;
1261:   const PetscInt *cells = NULL, *faces = NULL;
1262:   PetscInt        cStart = 0, cEnd = 0, fStart = 0, fEnd = 0;
1263:   PetscBT         cellFlip;    // The bit is true if a cell should have its orientation reversed
1264:   PetscInt       *cellComp;    // The connected component number of each cell
1265:   PetscInt       *faceComp;    // The connected component number of each face
1266:   PetscInt        Ncomp = 0;   // The number of local connected components
1267:   SharedFace     *localFace;   // Holds local information for owned and ghost shared faces
1268:   SharedFace     *remoteFace;  // Holds remote information from owners of shared faces
1269:   PetscInt       *Nneigh;      // The number of neighboring processes for each component
1270:   Neighbor      **neighbors;   // The neighbor for each component
1271:   PetscSFNode    *neighborAdj; // The (rank, comp) of each neighbor
1272:   PetscBool      *neighborVal; // Whether neighbors currently match
1273:   MPI_Comm        comm;
1274:   PetscMPIInt     rank, size;

1276:   PetscFunctionBegin;
1277:   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
1278:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
1279:   PetscCallMPI(MPI_Comm_size(comm, &size));
1280:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
1281:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
1282:   PetscCall(PetscBTCreate(cEnd - cStart, &cellFlip));
1283:   PetscCall(PetscBTMemzero(cEnd - cStart, cellFlip));
1284:   PetscCall(PetscCalloc2(cEnd - cStart, &cellComp, fEnd - fStart, &faceComp));
1285:   // Phase 1: Serial Orientation
1286:   PetscCall(DMPlexOrient_Serial(dm, cellIS, faceIS, &Ncomp, cellComp, faceComp, cellFlip));
1287:   if (debug) {
1288:     PetscViewer v;
1289:     PetscInt    cdepth = -1;

1291:     PetscCall(PetscViewerASCIIGetStdout(comm, &v));
1292:     PetscCall(PetscViewerASCIIPushSynchronized(v));
1293:     if (cEnd > cStart) PetscCall(DMPlexGetPointDepth(dm, cells ? cells[cStart] : cStart, &cdepth));
1294:     PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]New Orientation %" PetscInt_FMT " cells (depth %" PetscInt_FMT ") and %" PetscInt_FMT " faces\n", rank, cEnd - cStart, cdepth, fEnd - fStart));
1295:     PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]BT for serial flipped cells:\n", rank));
1296:     PetscCall(PetscBTView(cEnd - cStart, cellFlip, v));
1297:     PetscCall(PetscViewerFlush(v));
1298:     PetscCall(PetscViewerASCIIPopSynchronized(v));
1299:   }
1300:   if (size == 1) goto end;
1301:   // Phase 2
1302:   PetscCall(DMPlexOrientCreateSharedFaces_Internal(dm, cellIS, faceIS, Ncomp, faceComp, cellFlip, &localFace, &remoteFace));
1303:   // Phase 3
1304:   PetscCall(DMPlexOrientCreateNeighbors_Internal(dm, cellIS, faceIS, Ncomp, faceComp, localFace, remoteFace, &Nneigh, &neighbors));
1305:   PetscCall(PetscFree2(localFace, remoteFace));
1306:   // Phase 4
1307:   PetscCall(DMPlexOrientCreateProcessGraph_Internal(dm, faceIS, Ncomp, Nneigh, neighbors, &neighborAdj, &neighborVal));
1308:   // Phase 5
1309:   PetscCall(DMPlexOrientSolveProcessGraph_Internal(dm, cellIS, Ncomp, cellComp, Nneigh, neighborAdj, neighborVal, cellFlip));
1310:   if (debug) {
1311:     PetscViewer v;

1313:     PetscCall(PetscViewerASCIIGetStdout(comm, &v));
1314:     PetscCall(PetscViewerASCIIPushSynchronized(v));
1315:     PetscCall(PetscViewerASCIISynchronizedPrintf(v, "[%d]BT for parallel flipped cells:\n", rank));
1316:     PetscCall(PetscBTView(cEnd - cStart, cellFlip, v));
1317:     PetscCall(PetscViewerFlush(v));
1318:     PetscCall(PetscViewerASCIIPopSynchronized(v));
1319:   }
1320:   for (PetscInt c = 0; c < Ncomp; ++c) PetscCall(PetscFree(neighbors[c]));
1321:   PetscCall(PetscFree2(Nneigh, neighbors));
1322:   PetscCall(PetscFree2(neighborAdj, neighborVal));
1323: end:
1324:   // Phase 6
1325:   PetscCall(DMPlexOrientPlex_Internal(dm, cellIS, cellFlip));
1326:   PetscCall(PetscBTDestroy(&cellFlip));
1327:   PetscCall(PetscFree2(cellComp, faceComp));
1328:   PetscFunctionReturn(PETSC_SUCCESS);
1329: }

1331: static PetscErrorCode DMPlexCheckOrientation_Internal(DM dm, IS cellIS, IS faceIS)
1332: {
1333:   const PetscInt     debug  = ((DM_Plex *)dm->data)->printOrient;
1334:   PetscViewer        viewer = NULL, selfviewer = NULL;
1335:   PetscSF            sf;
1336:   const PetscInt    *lpoints, *rootdegree = NULL;
1337:   const PetscSFNode *rpoints;
1338:   const PetscInt    *cells = NULL, *faces = NULL;
1339:   PetscSFNode       *oornt, *rornt, *lornt;
1340:   PetscInt           cStart = 0, cEnd = 0, fStart = 0, fEnd = 0;
1341:   PetscInt           pdepth, Nr, Nl;
1342:   PetscBool          faceIsVertex = PETSC_FALSE, valid = PETSC_TRUE;
1343:   MPI_Comm           comm;
1344:   PetscMPIInt        size, rank;

1346:   PetscFunctionBegin;
1347:   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
1348:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
1349:   PetscCallMPI(MPI_Comm_size(comm, &size));
1350:   if (debug) {
1351:     viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)dm));
1352:     PetscCall(PetscViewerASCIIPushSynchronized(viewer));
1353:     PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
1354:   }

1356:   PetscCall(DMGetPointSF(dm, &sf));
1357:   PetscCall(PetscSFGetGraph(sf, &Nr, &Nl, &lpoints, &rpoints));
1358:   if (Nr >= 0) {
1359:     PetscCall(PetscSFComputeDegreeBegin(sf, &rootdegree));
1360:     PetscCall(PetscSFComputeDegreeEnd(sf, &rootdegree));
1361:   } else {
1362:     sf = NULL;
1363:     Nr = 0;
1364:     Nl = 0;
1365:   }
1366:   PetscCall(PetscCalloc3(Nr, &oornt, Nr, &rornt, Nl, &lornt));
1367:   if (cellIS) PetscCall(ISGetPointRange(cellIS, &cStart, &cEnd, &cells));
1368:   if (faceIS) PetscCall(ISGetPointRange(faceIS, &fStart, &fEnd, &faces));
1369:   PetscCall(DMPlexGetPointDepth(dm, faces ? faces[fStart] : fStart, &pdepth));
1370:   if (!pdepth) faceIsVertex = PETSC_TRUE;
1371:   if (debug) {
1372:     PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Checking orientation of %" PetscInt_FMT " cells and %" PetscInt_FMT " faces\n", rank, cEnd - cStart, fEnd - fStart));
1373:     PetscCall(PetscViewerASCIIPushTab(selfviewer));
1374:   }
1375:   for (PetscInt f = fStart; f < fEnd; ++f) {
1376:     const PetscInt  face  = faces ? faces[f] : f;
1377:     const PetscBool owner = rootdegree && rootdegree[face] ? PETSC_TRUE : PETSC_FALSE;
1378:     const PetscInt *supp;
1379:     PetscInt        neighbors[2], o[2] = {0, 0};
1380:     PetscInt        lsS = 0, sS;

1382:     PetscCall(DMPlexGetSupport(dm, face, &supp));
1383:     PetscCall(DMPlexGetSupportSize(dm, face, &sS));
1384:     // Filter support for local cells
1385:     for (PetscInt s = 0; s < sS; ++s) {
1386:       PetscInt ind;

1388:       ind = GetPointIndex(supp[s], cStart, cEnd, cells);
1389:       if (ind >= 0) {
1390:         neighbors[PetscMin(lsS, 1)] = supp[s];
1391:         ++lsS;
1392:       }
1393:     }
1394:     PetscCheck(lsS < 3, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Face %" PetscInt_FMT " has support size %" PetscInt_FMT " > 2", face, lsS);
1395:     // Extract orientations
1396:     for (PetscInt s = 0; s < lsS; ++s) {
1397:       const PetscInt *cone, *ornt;
1398:       PetscInt        cS;

1400:       PetscCall(DMPlexGetConeSize(dm, neighbors[s], &cS));
1401:       PetscCall(DMPlexGetOrientedCone(dm, neighbors[s], &cone, &ornt));
1402:       for (PetscInt c = 0; c < cS; ++c) {
1403:         if (cone[c] == face) {
1404:           if (faceIsVertex) o[s] = c * 2 - 1;
1405:           else o[s] = ornt[c] < 0 ? -1 : 1;
1406:           break;
1407:         }
1408:       }
1409:       PetscCall(DMPlexRestoreOrientedCone(dm, neighbors[s], &cone, &ornt));
1410:     }
1411:     if (lsS == 2) {
1412:       // Check internal face
1413:       if (o[0] * o[1] >= 0) {
1414:         valid = PETSC_FALSE;
1415:         if (debug)
1416:           PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Internal Face %" PetscInt_FMT " is mismatched: cell %" PetscInt_FMT " (%" PetscInt_FMT ") ~ cell %" PetscInt_FMT " (%" PetscInt_FMT ")\n", rank, face, neighbors[0], o[0], neighbors[1], o[1]));
1417:       } else if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Internal Face %" PetscInt_FMT " valid\n", rank, face));
1418:     } else {
1419:       // Check shared and boundary faces
1420:       PetscInt l;

1422:       PetscCall(PetscFindInt(face, Nl, lpoints, &l));
1423:       // Boundary face
1424:       if (l < 0 && !owner) {
1425:         if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Boundary Face %" PetscInt_FMT " valid\n", rank, face));
1426:         continue;
1427:       }
1428:       if (l >= 0) {
1429:         lornt[l].index = neighbors[0];
1430:         lornt[l].rank  = o[0];
1431:         if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Ghost Face %" PetscInt_FMT " (%" PetscInt_FMT ") was stored\n", rank, face, o[0]));
1432:       }
1433:     }
1434:     if (owner) {
1435:       // Store shared face orientation and cell from owner
1436:       oornt[face].index = neighbors[0];
1437:       oornt[face].rank  = o[0];
1438:       if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Owned Face %" PetscInt_FMT " (%" PetscInt_FMT ") was stored\n", rank, face, o[0]));
1439:     }
1440:   }
1441:   // Communicate shared face orientations from owner
1442:   if (sf) {
1443:     PetscCall(PetscSFBcastBegin(sf, MPIU_SF_NODE, oornt, rornt, MPI_REPLACE));
1444:     PetscCall(PetscSFBcastEnd(sf, MPIU_SF_NODE, oornt, rornt, MPI_REPLACE));
1445:   }
1446:   // Check unowned shared faces
1447:   for (PetscInt l = 0; l < Nl; ++l) {
1448:     const PetscInt face = lpoints ? lpoints[l] : l;
1449:     PetscBool      flip = PETSC_FALSE;
1450:     PetscInt       ind, cl, o[2] = {0, 0};

1452:     // Filter for local faces
1453:     ind = GetPointIndex(face, fStart, fEnd, faces);
1454:     if (ind < 0) continue;
1455:     // Check for shared cell
1456:     PetscCall(PetscFindInt(lornt[l].index, Nl, lpoints, &cl));
1457:     if (cl >= 0) {
1458:       if (rpoints[cl].index == rornt[face].index) {
1459:         flip = PETSC_TRUE;
1460:         if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "Shared cell %" PetscInt_FMT " maps to %" PetscInt_FMT " (%" PetscInt_FMT ") so we reverse the orientation check\n", lornt[l].index, rpoints[cl].index, rpoints[cl].rank));
1461:       } else {
1462:         if (debug > 1)
1463:           PetscCall(PetscViewerASCIIPrintf(selfviewer, "Shared cell %" PetscInt_FMT " maps to %" PetscInt_FMT " (%" PetscInt_FMT ") instead of %" PetscInt_FMT " so we do not reverse the orientation check\n", lornt[l].index, rpoints[cl].index,
1464:                                            rpoints[cl].rank, rornt[face].index));
1465:       }
1466:     }
1467:     o[0] = lornt[l].rank;
1468:     o[1] = rornt[face].rank;
1469:     // This was not a shared face
1470:     if (!o[0]) continue;
1471:     if ((o[0] * o[1] >= 0 && !flip) || (o[0] * o[1] < 0 && flip)) {
1472:       valid = PETSC_FALSE;
1473:       if (debug)
1474:         PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Ghost Face %" PetscInt_FMT " (%" PetscInt_FMT ") does not match face %" PetscInt_FMT " rank %" PetscInt_FMT " (%" PetscInt_FMT ")\n", rank, face, o[0], rpoints[l].index, rpoints[l].rank, o[1]));
1475:     } else if (debug > 1) PetscCall(PetscViewerASCIIPrintf(selfviewer, "[%d]Ghost Face %" PetscInt_FMT " matches %" PetscInt_FMT " (%" PetscInt_FMT ") valid\n", rank, face, rpoints[l].index, rpoints[l].rank));
1476:   }
1477:   // Cleanup
1478:   PetscCall(PetscFree3(oornt, rornt, lornt));
1479:   if (debug) {
1480:     PetscCall(PetscViewerASCIIPopTab(selfviewer));
1481:     PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &selfviewer));
1482:     PetscCall(PetscViewerASCIIPopSynchronized(viewer));
1483:   }
1484:   PetscCallMPI(MPIU_Allreduce(MPI_IN_PLACE, &valid, 1, MPI_C_BOOL, MPI_LAND, comm));
1485:   PetscCheck(valid, comm, PETSC_ERR_ARG_WRONGSTATE, "Mesh was not properly oriented");
1486:   PetscFunctionReturn(PETSC_SUCCESS);
1487: }

1489: /*@
1490:   DMPlexCheckOrientationLabel - Check that the surface defined by the given `DMLabel` is oriented

1492:   Collective

1494:   Input Parameters:
1495: + dm    - The `DM`
1496: - label - The `DMLabel` defining the embedded surface

1498:   Level: advanced

1500: .seealso: [](ch_unstructured), `DM`, `DMPLEX`, `DMPlexOrient()`
1501: @*/
1502: PetscErrorCode DMPlexCheckOrientationLabel(DM dm, DMLabel label)
1503: {
1504:   IS cellIS, faceIS;

1506:   PetscFunctionBegin;
1507:   PetscCall(CreateCellAndFaceIS_Private(dm, label, &cellIS, &faceIS));
1508:   PetscCall(DMPlexCheckOrientation_Internal(dm, cellIS, faceIS));
1509:   PetscCall(ISDestroy(&cellIS));
1510:   PetscCall(ISDestroy(&faceIS));
1511:   PetscFunctionReturn(PETSC_SUCCESS);
1512: }