xref: /petsc/src/dm/impls/plex/plexgmsh.c (revision dc0ede3b2d8930c17f6a5a2dca55010b4dbbd717)
1 #define PETSCDM_DLL
2 #include <petsc/private/dmpleximpl.h>    /*I   "petscdmplex.h"   I*/
3 
4 #undef __FUNCT__
5 #define __FUNCT__ "DMPlexCreateGmshFromFile"
6 /*@C
7   DMPlexCreateGmshFromFile - Create a DMPlex mesh from a Gmsh file
8 
9 + comm        - The MPI communicator
10 . filename    - Name of the Gmsh file
11 - interpolate - Create faces and edges in the mesh
12 
13   Output Parameter:
14 . dm  - The DM object representing the mesh
15 
16   Level: beginner
17 
18 .seealso: DMPlexCreateFromFile(), DMPlexCreateGmsh(), DMPlexCreate()
19 @*/
20 PetscErrorCode DMPlexCreateGmshFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
21 {
22   PetscViewer     viewer, vheader;
23   PetscMPIInt     rank;
24   PetscViewerType vtype;
25   char            line[PETSC_MAX_PATH_LEN];
26   int             snum;
27   PetscBool       match;
28   int             fT;
29   PetscInt        fileType;
30   float           version;
31   PetscErrorCode  ierr;
32 
33   PetscFunctionBegin;
34   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
35   /* Determine Gmsh file type (ASCII or binary) from file header */
36   ierr = PetscViewerCreate(comm, &vheader);CHKERRQ(ierr);
37   ierr = PetscViewerSetType(vheader, PETSCVIEWERASCII);CHKERRQ(ierr);
38   ierr = PetscViewerFileSetMode(vheader, FILE_MODE_READ);CHKERRQ(ierr);
39   ierr = PetscViewerFileSetName(vheader, filename);CHKERRQ(ierr);
40   if (!rank) {
41     /* Read only the first two lines of the Gmsh file */
42     ierr = PetscViewerRead(vheader, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
43     ierr = PetscStrncmp(line, "$MeshFormat", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
44     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
45     ierr = PetscViewerRead(vheader, line, 2, NULL, PETSC_STRING);CHKERRQ(ierr);
46     snum = sscanf(line, "%f %d", &version, &fT);
47     fileType = (PetscInt) fT;
48     if (snum != 2) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unable to parse Gmsh file header: %s", line);
49     if (version < 2.0) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Gmsh file must be at least version 2.0");
50   }
51   ierr = MPI_Bcast(&fileType, 1, MPIU_INT, 0, comm);CHKERRQ(ierr);
52   /* Create appropriate viewer and build plex */
53   if (fileType == 0) vtype = PETSCVIEWERASCII;
54   else vtype = PETSCVIEWERBINARY;
55   ierr = PetscViewerCreate(comm, &viewer);CHKERRQ(ierr);
56   ierr = PetscViewerSetType(viewer, vtype);CHKERRQ(ierr);
57   ierr = PetscViewerFileSetMode(viewer, FILE_MODE_READ);CHKERRQ(ierr);
58   ierr = PetscViewerFileSetName(viewer, filename);CHKERRQ(ierr);
59   ierr = DMPlexCreateGmsh(comm, viewer, interpolate, dm);CHKERRQ(ierr);
60   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
61   ierr = PetscViewerDestroy(&vheader);CHKERRQ(ierr);
62   PetscFunctionReturn(0);
63 }
64 
65 
66 #undef __FUNCT__
67 #define __FUNCT__ "DMPlexCreateGmsh"
68 /*@
69   DMPlexCreateGmsh - Create a DMPlex mesh from a Gmsh file viewer
70 
71   Collective on comm
72 
73   Input Parameters:
74 + comm  - The MPI communicator
75 . viewer - The Viewer associated with a Gmsh file
76 - interpolate - Create faces and edges in the mesh
77 
78   Output Parameter:
79 . dm  - The DM object representing the mesh
80 
81   Note: http://www.geuz.org/gmsh/doc/texinfo/#MSH-ASCII-file-format
82   and http://www.geuz.org/gmsh/doc/texinfo/#MSH-binary-file-format
83 
84   Level: beginner
85 
86 .keywords: mesh,Gmsh
87 .seealso: DMPLEX, DMCreate()
88 @*/
89 PetscErrorCode DMPlexCreateGmsh(MPI_Comm comm, PetscViewer viewer, PetscBool interpolate, DM *dm)
90 {
91   PetscViewerType vtype;
92   GmshElement   *gmsh_elem;
93   PetscSection   coordSection;
94   Vec            coordinates;
95   PetscScalar   *coords, *coordsIn = NULL;
96   PetscInt       dim = 0, coordSize, c, v, d, r, cell;
97   int            i, numVertices = 0, numCells = 0, trueNumCells = 0, numRegions = 0, snum;
98   PetscMPIInt    num_proc, rank;
99   char           line[PETSC_MAX_PATH_LEN];
100   PetscBool      match, binary, bswap = PETSC_FALSE;
101   PetscErrorCode ierr;
102 
103   PetscFunctionBegin;
104   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
105   ierr = MPI_Comm_size(comm, &num_proc);CHKERRQ(ierr);
106   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
107   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
108   ierr = PetscLogEventBegin(DMPLEX_CreateGmsh,*dm,0,0,0);CHKERRQ(ierr);
109   ierr = PetscViewerGetType(viewer, &vtype);CHKERRQ(ierr);
110   ierr = PetscStrcmp(vtype, PETSCVIEWERBINARY, &binary);CHKERRQ(ierr);
111   if (!rank || binary) {
112     PetscBool match;
113     int       fileType, dataSize;
114     float     version;
115 
116     /* Read header */
117     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
118     ierr = PetscStrncmp(line, "$MeshFormat", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
119     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
120     ierr = PetscViewerRead(viewer, line, 3, NULL, PETSC_STRING);CHKERRQ(ierr);
121     snum = sscanf(line, "%f %d %d", &version, &fileType, &dataSize);
122     if (snum != 3) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unable to parse Gmsh file header: %s", line);
123     if (version < 2.0) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Gmsh file must be at least version 2.0");
124     if (dataSize != sizeof(double)) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Data size %d is not valid for a Gmsh file", dataSize);
125     if (binary) {
126       int checkInt;
127       ierr = PetscViewerRead(viewer, &checkInt, 1, NULL, PETSC_ENUM);CHKERRQ(ierr);
128       if (checkInt != 1) {
129         ierr = PetscByteSwap(&checkInt, PETSC_ENUM, 1);CHKERRQ(ierr);
130         if (checkInt == 1) bswap = PETSC_TRUE;
131         else SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File type %d is not a valid Gmsh binary file", fileType);
132       }
133     } else if (fileType) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File type %d is not a valid Gmsh ASCII file", fileType);
134     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
135     ierr = PetscStrncmp(line, "$EndMeshFormat", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
136     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
137     /* OPTIONAL Read physical names */
138     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
139     ierr = PetscStrncmp(line, "$PhysicalNames", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
140     if (match) {
141       ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
142       snum = sscanf(line, "%d", &numRegions);
143       if (snum != 1) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
144       for (r = 0; r < numRegions; ++r) {
145         PetscInt rdim, tag;
146 
147         ierr = PetscViewerRead(viewer, &rdim, 1, NULL, PETSC_ENUM);CHKERRQ(ierr);
148         ierr = PetscViewerRead(viewer, &tag,  1, NULL, PETSC_ENUM);CHKERRQ(ierr);
149         ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
150       }
151       ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
152       ierr = PetscStrncmp(line, "$EndPhysicalNames", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
153       if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
154       /* Initial read for vertex section */
155       ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
156     }
157     /* Read vertices */
158     ierr = PetscStrncmp(line, "$Nodes", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
159     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
160     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
161     snum = sscanf(line, "%d", &numVertices);
162     if (snum != 1) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
163     ierr = PetscMalloc1(numVertices*3, &coordsIn);CHKERRQ(ierr);
164     if (binary) {
165       size_t doubleSize, intSize;
166       PetscInt elementSize;
167       char *buffer;
168       PetscScalar *baseptr;
169       ierr = PetscDataTypeGetSize(PETSC_ENUM, &intSize);CHKERRQ(ierr);
170       ierr = PetscDataTypeGetSize(PETSC_DOUBLE, &doubleSize);CHKERRQ(ierr);
171       elementSize = (intSize + 3*doubleSize);
172       ierr = PetscMalloc1(elementSize*numVertices, &buffer);CHKERRQ(ierr);
173       ierr = PetscViewerRead(viewer, buffer, elementSize*numVertices, NULL, PETSC_CHAR);CHKERRQ(ierr);
174       if (bswap) ierr = PetscByteSwap(buffer, PETSC_CHAR, elementSize*numVertices);CHKERRQ(ierr);
175       for (v = 0; v < numVertices; ++v) {
176         baseptr = ((PetscScalar*)(buffer+v*elementSize+intSize));
177         coordsIn[v*3+0] = baseptr[0];
178         coordsIn[v*3+1] = baseptr[1];
179         coordsIn[v*3+2] = baseptr[2];
180       }
181       ierr = PetscFree(buffer);CHKERRQ(ierr);
182     } else {
183       for (v = 0; v < numVertices; ++v) {
184         ierr = PetscViewerRead(viewer, &i, 1, NULL, PETSC_ENUM);CHKERRQ(ierr);
185         ierr = PetscViewerRead(viewer, &(coordsIn[v*3]), 3, NULL, PETSC_DOUBLE);CHKERRQ(ierr);
186         if (i != (int)v+1) SETERRQ2(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid node number %d should be %d", i, v+1);
187       }
188     }
189     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
190     ierr = PetscStrncmp(line, "$EndNodes", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
191     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
192     /* Read cells */
193     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
194     ierr = PetscStrncmp(line, "$Elements", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
195     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
196     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
197     snum = sscanf(line, "%d", &numCells);
198     if (snum != 1) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
199   }
200 
201   if (!rank || binary) {
202     /* Gmsh elements can be of any dimension/co-dimension, so we need to traverse the
203        file contents multiple times to figure out the true number of cells and facets
204        in the given mesh. To make this more efficient we read the file contents only
205        once and store them in memory, while determining the true number of cells. */
206     ierr = DMPlexCreateGmsh_ReadElement(viewer, numCells, binary, bswap, &gmsh_elem);CHKERRQ(ierr);
207     for (trueNumCells=0, c = 0; c < numCells; ++c) {
208       if (gmsh_elem[c].dim > dim) {dim = gmsh_elem[c].dim; trueNumCells = 0;}
209       if (gmsh_elem[c].dim == dim) trueNumCells++;
210     }
211     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
212     ierr = PetscStrncmp(line, "$EndElements", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
213     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
214   }
215   /* For binary we read on all ranks, but only build the plex on rank 0 */
216   if (binary && rank) {trueNumCells = 0; numVertices = 0;};
217   /* Allocate the cell-vertex mesh */
218   ierr = DMPlexSetChart(*dm, 0, trueNumCells+numVertices);CHKERRQ(ierr);
219   if (!rank) {
220     for (cell = 0, c = 0; c < numCells; ++c) {
221       if (gmsh_elem[c].dim == dim) {
222         ierr = DMPlexSetConeSize(*dm, cell, gmsh_elem[c].numNodes);CHKERRQ(ierr);
223         cell++;
224       }
225     }
226   }
227   ierr = DMSetUp(*dm);CHKERRQ(ierr);
228   /* Add cell-vertex connections */
229   if (!rank) {
230     PetscInt pcone[8], corner;
231     for (cell = 0, c = 0; c < numCells; ++c) {
232       if (gmsh_elem[c].dim == dim) {
233         for (corner = 0; corner < gmsh_elem[c].numNodes; ++corner) {
234           pcone[corner] = gmsh_elem[c].nodes[corner] + trueNumCells-1;
235         }
236         ierr = DMPlexSetCone(*dm, cell, pcone);CHKERRQ(ierr);
237         cell++;
238       }
239     }
240   }
241   ierr = MPI_Bcast(&dim, 1, MPIU_INT, 0, comm);CHKERRQ(ierr);
242   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
243   ierr = DMPlexSymmetrize(*dm);CHKERRQ(ierr);
244   ierr = DMPlexStratify(*dm);CHKERRQ(ierr);
245   if (interpolate) {
246     DM idm = NULL;
247 
248     ierr = DMPlexInterpolate(*dm, &idm);CHKERRQ(ierr);
249     ierr = DMDestroy(dm);CHKERRQ(ierr);
250     *dm  = idm;
251   }
252 
253   if (!rank) {
254     /* Apply boundary IDs by finding the relevant facets with vertex joins */
255     PetscInt pcone[8], corner, vStart, vEnd;
256 
257     ierr = DMPlexGetDepthStratum(*dm, 0, &vStart, &vEnd);CHKERRQ(ierr);
258     for (c = 0; c < numCells; ++c) {
259       if (gmsh_elem[c].dim == dim-1) {
260         PetscInt joinSize;
261         const PetscInt *join;
262         for (corner = 0; corner < gmsh_elem[c].numNodes; ++corner) {
263           pcone[corner] = gmsh_elem[c].nodes[corner] + vStart - 1;
264         }
265         ierr = DMPlexGetFullJoin(*dm, gmsh_elem[c].numNodes, (const PetscInt *) pcone, &joinSize, &join);CHKERRQ(ierr);
266         if (joinSize != 1) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Could not determine Plex facet for element %d", gmsh_elem[c].id);
267         ierr = DMSetLabelValue(*dm, "Face Sets", join[0], gmsh_elem[c].tags[0]);CHKERRQ(ierr);
268         ierr = DMPlexRestoreJoin(*dm, gmsh_elem[c].numNodes, (const PetscInt *) pcone, &joinSize, &join);CHKERRQ(ierr);
269       }
270     }
271   }
272 
273   /* Read coordinates */
274   ierr = DMGetCoordinateSection(*dm, &coordSection);CHKERRQ(ierr);
275   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
276   ierr = PetscSectionSetFieldComponents(coordSection, 0, dim);CHKERRQ(ierr);
277   ierr = PetscSectionSetChart(coordSection, trueNumCells, trueNumCells + numVertices);CHKERRQ(ierr);
278   for (v = trueNumCells; v < trueNumCells+numVertices; ++v) {
279     ierr = PetscSectionSetDof(coordSection, v, dim);CHKERRQ(ierr);
280     ierr = PetscSectionSetFieldDof(coordSection, v, 0, dim);CHKERRQ(ierr);
281   }
282   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
283   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
284   ierr = VecCreate(comm, &coordinates);CHKERRQ(ierr);
285   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
286   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
287   ierr = VecSetType(coordinates, VECSTANDARD);CHKERRQ(ierr);
288   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
289   if (!rank) {
290     for (v = 0; v < numVertices; ++v) {
291       for (d = 0; d < dim; ++d) {
292         coords[v*dim+d] = coordsIn[v*3+d];
293       }
294     }
295   }
296   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
297   ierr = PetscFree(coordsIn);CHKERRQ(ierr);
298   ierr = DMSetCoordinatesLocal(*dm, coordinates);CHKERRQ(ierr);
299   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
300   /* Clean up intermediate storage */
301   if (!rank || binary) ierr = PetscFree(gmsh_elem);CHKERRQ(ierr);
302   ierr = PetscLogEventEnd(DMPLEX_CreateGmsh,*dm,0,0,0);CHKERRQ(ierr);
303   PetscFunctionReturn(0);
304 }
305 
306 #undef __FUNCT__
307 #define __FUNCT__ "DMPlexCreateGmsh_ReadElement"
308 PetscErrorCode DMPlexCreateGmsh_ReadElement(PetscViewer viewer, PetscInt numCells, PetscBool binary, PetscBool byteSwap, GmshElement **gmsh_elems)
309 {
310   PetscInt       c, p;
311   GmshElement   *elements;
312   int            i, cellType, dim, numNodes, numElem, numTags;
313   int            ibuf[16];
314   PetscErrorCode ierr;
315 
316   PetscFunctionBegin;
317   ierr = PetscMalloc1(numCells, &elements);CHKERRQ(ierr);
318   for (c = 0; c < numCells;) {
319     ierr = PetscViewerRead(viewer, &ibuf, 3, NULL, PETSC_ENUM);CHKERRQ(ierr);
320     if (byteSwap) ierr = PetscByteSwap(&ibuf, PETSC_ENUM, 3);CHKERRQ(ierr);
321     if (binary) {
322       cellType = ibuf[0];
323       numElem = ibuf[1];
324       numTags = ibuf[2];
325     } else {
326       elements[c].id = ibuf[0];
327       cellType = ibuf[1];
328       numTags = ibuf[2];
329       numElem = 1;
330     }
331     switch (cellType) {
332     case 1: /* 2-node line */
333       dim = 1;
334       numNodes = 2;
335       break;
336     case 2: /* 3-node triangle */
337       dim = 2;
338       numNodes = 3;
339       break;
340     case 3: /* 4-node quadrangle */
341       dim = 2;
342       numNodes = 4;
343       break;
344     case 4: /* 4-node tetrahedron */
345       dim  = 3;
346       numNodes = 4;
347       break;
348     case 5: /* 8-node hexahedron */
349       dim = 3;
350       numNodes = 8;
351       break;
352     case 15: /* 1-node vertex */
353       dim = 0;
354       numNodes = 1;
355       break;
356     default:
357       SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unsupported Gmsh element type %d", cellType);
358     }
359     if (binary) {
360       const PetscInt nint = numNodes + numTags + 1;
361       for (i = 0; i < numElem; ++i, ++c) {
362         /* Loop over inner binary element block */
363         elements[c].dim = dim;
364         elements[c].numNodes = numNodes;
365         elements[c].numTags = numTags;
366 
367         ierr = PetscViewerRead(viewer, &ibuf, nint, NULL, PETSC_ENUM);CHKERRQ(ierr);
368         if (byteSwap) ierr = PetscByteSwap( &ibuf, PETSC_ENUM, nint);CHKERRQ(ierr);
369         elements[c].id = ibuf[0];
370         for (p = 0; p < numTags; p++) elements[c].tags[p] = ibuf[1 + p];
371         for (p = 0; p < numNodes; p++) elements[c].nodes[p] = ibuf[1 + numTags + p];
372       }
373     } else {
374       elements[c].dim = dim;
375       elements[c].numNodes = numNodes;
376       elements[c].numTags = numTags;
377       ierr = PetscViewerRead(viewer, elements[c].tags, elements[c].numTags, NULL, PETSC_ENUM);CHKERRQ(ierr);
378       ierr = PetscViewerRead(viewer, elements[c].nodes, elements[c].numNodes, NULL, PETSC_ENUM);CHKERRQ(ierr);
379       c++;
380     }
381   }
382   *gmsh_elems = elements;
383   PetscFunctionReturn(0);
384 }
385