xref: /petsc/src/dm/impls/plex/plexgmsh.c (revision b6a3fe3c56097d5d92c7d822d284fb4cf15ccc65)
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, cell;
97   int            numVertices = 0, numCells = 0, trueNumCells = 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, "$EndMeshFormat", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
136     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
137     /* Read vertices */
138     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
139     ierr = PetscStrncmp(line, "$Nodes", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
140     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
141     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);
142     snum = sscanf(line, "%d", &numVertices);
143     if (snum != 1) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
144     ierr = PetscMalloc1(numVertices*3, &coordsIn);CHKERRQ(ierr);
145     for (v = 0; v < numVertices; ++v) {
146       int i;
147       ierr = PetscViewerRead(viewer, &i, 1, NULL, PETSC_ENUM);CHKERRQ(ierr);
148       if (bswap) ierr = PetscByteSwap(&i, PETSC_ENUM, 1);CHKERRQ(ierr);
149       ierr = PetscViewerRead(viewer, &(coordsIn[v*3]), 3, NULL, PETSC_DOUBLE);CHKERRQ(ierr);
150       if (bswap) ierr = PetscByteSwap(&(coordsIn[v*3]), PETSC_DOUBLE, 3);CHKERRQ(ierr);
151       if (i != (int)v+1) SETERRQ2(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid node number %d should be %d", i, v+1);
152     }
153     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
154     ierr = PetscStrncmp(line, "$EndNodes", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
155     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
156     /* Read cells */
157     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
158     ierr = PetscStrncmp(line, "$Elements", 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", &numCells);
162     if (snum != 1) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
163   }
164 
165   if (!rank || binary) {
166     /* Gmsh elements can be of any dimension/co-dimension, so we need to traverse the
167        file contents multiple times to figure out the true number of cells and facets
168        in the given mesh. To make this more efficient we read the file contents only
169        once and store them in memory, while determining the true number of cells. */
170     ierr = DMPlexCreateGmsh_ReadElement(viewer, numCells, binary, bswap, &gmsh_elem);CHKERRQ(ierr);
171     for (trueNumCells=0, c = 0; c < numCells; ++c) {
172       if (gmsh_elem[c].dim > dim) {dim = gmsh_elem[c].dim; trueNumCells = 0;}
173       if (gmsh_elem[c].dim == dim) trueNumCells++;
174     }
175     ierr = PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);CHKERRQ(ierr);;
176     ierr = PetscStrncmp(line, "$EndElements", PETSC_MAX_PATH_LEN, &match);CHKERRQ(ierr);
177     if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
178   }
179   /* For binary we read on all ranks, but only build the plex on rank 0 */
180   if (binary && rank) {trueNumCells = 0; numVertices = 0;};
181   /* Allocate the cell-vertex mesh */
182   ierr = DMPlexSetChart(*dm, 0, trueNumCells+numVertices);CHKERRQ(ierr);
183   if (!rank) {
184     for (cell = 0, c = 0; c < numCells; ++c) {
185       if (gmsh_elem[c].dim == dim) {
186         ierr = DMPlexSetConeSize(*dm, cell, gmsh_elem[c].numNodes);CHKERRQ(ierr);
187         cell++;
188       }
189     }
190   }
191   ierr = DMSetUp(*dm);CHKERRQ(ierr);
192   /* Add cell-vertex connections */
193   if (!rank) {
194     PetscInt pcone[8], corner;
195     for (cell = 0, c = 0; c < numCells; ++c) {
196       if (gmsh_elem[c].dim == dim) {
197         for (corner = 0; corner < gmsh_elem[c].numNodes; ++corner) {
198           pcone[corner] = gmsh_elem[c].nodes[corner] + trueNumCells-1;
199         }
200         ierr = DMPlexSetCone(*dm, cell, pcone);CHKERRQ(ierr);
201         cell++;
202       }
203     }
204   }
205   ierr = MPI_Bcast(&dim, 1, MPIU_INT, 0, comm);CHKERRQ(ierr);
206   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
207   ierr = DMPlexSymmetrize(*dm);CHKERRQ(ierr);
208   ierr = DMPlexStratify(*dm);CHKERRQ(ierr);
209   if (interpolate) {
210     DM idm = NULL;
211 
212     ierr = DMPlexInterpolate(*dm, &idm);CHKERRQ(ierr);
213     ierr = DMDestroy(dm);CHKERRQ(ierr);
214     *dm  = idm;
215   }
216 
217   if (!rank) {
218     /* Apply boundary IDs by finding the relevant facets with vertex joins */
219     PetscInt pcone[8], corner, vStart, vEnd;
220 
221     ierr = DMPlexGetDepthStratum(*dm, 0, &vStart, &vEnd);CHKERRQ(ierr);
222     for (c = 0; c < numCells; ++c) {
223       if (gmsh_elem[c].dim == dim-1) {
224         PetscInt joinSize;
225         const PetscInt *join;
226         for (corner = 0; corner < gmsh_elem[c].numNodes; ++corner) {
227           pcone[corner] = gmsh_elem[c].nodes[corner] + vStart - 1;
228         }
229         ierr = DMPlexGetFullJoin(*dm, gmsh_elem[c].numNodes, (const PetscInt *) pcone, &joinSize, &join);CHKERRQ(ierr);
230         if (joinSize != 1) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Could not determine Plex facet for element %d", gmsh_elem[c].id);
231         ierr = DMPlexSetLabelValue(*dm, "Face Sets", join[0], gmsh_elem[c].tags[0]);CHKERRQ(ierr);
232         ierr = DMPlexRestoreJoin(*dm, gmsh_elem[c].numNodes, (const PetscInt *) pcone, &joinSize, &join);CHKERRQ(ierr);
233       }
234     }
235   }
236 
237   /* Read coordinates */
238   ierr = DMGetCoordinateSection(*dm, &coordSection);CHKERRQ(ierr);
239   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
240   ierr = PetscSectionSetFieldComponents(coordSection, 0, dim);CHKERRQ(ierr);
241   ierr = PetscSectionSetChart(coordSection, trueNumCells, trueNumCells + numVertices);CHKERRQ(ierr);
242   for (v = trueNumCells; v < trueNumCells+numVertices; ++v) {
243     ierr = PetscSectionSetDof(coordSection, v, dim);CHKERRQ(ierr);
244     ierr = PetscSectionSetFieldDof(coordSection, v, 0, dim);CHKERRQ(ierr);
245   }
246   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
247   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
248   ierr = VecCreate(comm, &coordinates);CHKERRQ(ierr);
249   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
250   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
251   ierr = VecSetType(coordinates, VECSTANDARD);CHKERRQ(ierr);
252   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
253   if (!rank) {
254     for (v = 0; v < numVertices; ++v) {
255       for (d = 0; d < dim; ++d) {
256         coords[v*dim+d] = coordsIn[v*3+d];
257       }
258     }
259   }
260   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
261   ierr = PetscFree(coordsIn);CHKERRQ(ierr);
262   ierr = DMSetCoordinatesLocal(*dm, coordinates);CHKERRQ(ierr);
263   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
264   /* Clean up intermediate storage */
265   if (!rank || binary) ierr = PetscFree(gmsh_elem);CHKERRQ(ierr);
266   ierr = PetscLogEventEnd(DMPLEX_CreateGmsh,*dm,0,0,0);CHKERRQ(ierr);
267   PetscFunctionReturn(0);
268 }
269 
270 #undef __FUNCT__
271 #define __FUNCT__ "DMPlexCreateGmsh_ReadElement"
272 PetscErrorCode DMPlexCreateGmsh_ReadElement(PetscViewer viewer, PetscInt numCells, PetscBool binary, PetscBool byteSwap, GmshElement **gmsh_elems)
273 {
274   PetscInt       c;
275   GmshElement   *elements;
276   int            i, cellType, dim, numNodes, numElem, numTags;
277   int            ibuf[4];
278   PetscErrorCode ierr;
279 
280   PetscFunctionBegin;
281   ierr = PetscMalloc1(numCells, &elements);CHKERRQ(ierr);
282   for (c = 0; c < numCells;) {
283     ierr = PetscViewerRead(viewer, &ibuf, 3, NULL, PETSC_ENUM);CHKERRQ(ierr);
284     if (byteSwap) ierr = PetscByteSwap(&ibuf, PETSC_ENUM, 3);CHKERRQ(ierr);
285     if (binary) {
286       cellType = ibuf[0];
287       numElem = ibuf[1];
288       numTags = ibuf[2];
289     } else {
290       elements[c].id = ibuf[0];
291       cellType = ibuf[1];
292       numTags = ibuf[2];
293       numElem = 1;
294     }
295     switch (cellType) {
296     case 1: /* 2-node line */
297       dim = 1;
298       numNodes = 2;
299       break;
300     case 2: /* 3-node triangle */
301       dim = 2;
302       numNodes = 3;
303       break;
304     case 3: /* 4-node quadrangle */
305       dim = 2;
306       numNodes = 4;
307       break;
308     case 4: /* 4-node tetrahedron */
309       dim  = 3;
310       numNodes = 4;
311       break;
312     case 5: /* 8-node hexahedron */
313       dim = 3;
314       numNodes = 8;
315       break;
316     case 15: /* 1-node vertex */
317       dim = 0;
318       numNodes = 1;
319       break;
320     default:
321       SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unsupported Gmsh element type %d", cellType);
322     }
323     for (i = 0; i < numElem; ++i, ++c) {
324       /* Loop over inner binary element block */
325       if (binary) {
326         ierr = PetscViewerRead(viewer,  &(elements[c].id), 1, NULL, PETSC_ENUM);CHKERRQ(ierr);
327         if (byteSwap) ierr = PetscByteSwap( &(elements[c].id), PETSC_ENUM, 1);CHKERRQ(ierr);
328       }
329       elements[c].dim = dim;
330       elements[c].numNodes = numNodes;
331       elements[c].numTags = numTags;
332 
333       ierr = PetscViewerRead(viewer, elements[c].tags, elements[c].numTags, NULL, PETSC_ENUM);CHKERRQ(ierr);
334       if (byteSwap) ierr = PetscByteSwap(elements[c].tags, PETSC_ENUM, elements[c].numTags);CHKERRQ(ierr);
335       ierr = PetscViewerRead(viewer, elements[c].nodes, elements[c].numNodes, NULL, PETSC_ENUM);CHKERRQ(ierr);
336       if (byteSwap) {ierr = PetscByteSwap(elements[c].nodes, PETSC_ENUM, elements[c].numNodes);CHKERRQ(ierr);}
337     }
338   }
339   *gmsh_elems = elements;
340   PetscFunctionReturn(0);
341 }
342