Date: 2022-08-02T03:14:16+00:00

Actual source code: plexply.c

      1: #define PETSCDM_DLL
      2: #include <petsc/private/dmpleximpl.h>

      4: /*@C
      5:   DMPlexCreatePLYFromFile - Create a DMPlex mesh from a PLY file.

      7: + comm        - The MPI communicator
      8: . filename    - Name of the .med file
      9: - interpolate - Create faces and edges in the mesh

     11:   Output Parameter:
     12: . dm  - The DM object representing the mesh

     14:   Note: https://en.wikipedia.org/wiki/PLY_(file_format)

     16:   Level: beginner

     18: .seealso: DMPlexCreateFromFile(), DMPlexCreateMedFromFile(), DMPlexCreateGmsh(), DMPlexCreate()
     19: @*/
     20: PetscErrorCode DMPlexCreatePLYFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
     21: {
     22:   PetscViewer     viewer;
     23:   Vec             coordinates;
     24:   PetscSection    coordSection;
     25:   PetscScalar    *coords;
     26:   char            line[PETSC_MAX_PATH_LEN], ntype[16], itype[16], name[1024], vtype[16];
     27:   PetscBool       match, byteSwap = PETSC_FALSE;
     28:   PetscInt        dim = 2, cdim = 3, Nvp = 0, coordSize, xi = -1, yi = -1, zi = -1, v, c, p;
     29:   PetscMPIInt     rank;
     30:   int             snum, Nv, Nc;

     32:   MPI_Comm_rank(comm, &rank);
     33:   PetscViewerCreate(comm, &viewer);
     34:   PetscViewerSetType(viewer, PETSCVIEWERBINARY);
     35:   PetscViewerFileSetMode(viewer, FILE_MODE_READ);
     36:   PetscViewerFileSetName(viewer, filename);
     37:   if (rank == 0) {
     38:     PetscBool isAscii, isBinaryBig, isBinaryLittle;

     40:     /* Check for PLY file */
     41:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     42:     PetscStrncmp(line, "ply", PETSC_MAX_PATH_LEN, &match);
     44:     /* Check PLY format */
     45:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     46:     PetscStrncmp(line, "format", PETSC_MAX_PATH_LEN, &match);
     48:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     49:     PetscStrncmp(line, "ascii", PETSC_MAX_PATH_LEN, &isAscii);
     50:     PetscStrncmp(line, "binary_big_endian", PETSC_MAX_PATH_LEN, &isBinaryBig);
     51:     PetscStrncmp(line, "binary_little_endian", PETSC_MAX_PATH_LEN, &isBinaryLittle);
     53:     else if (isBinaryLittle) byteSwap = PETSC_TRUE;
     54:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     55:     PetscStrncmp(line, "1.0", PETSC_MAX_PATH_LEN, &match);
     57:     /* Ignore comments */
     58:     match = PETSC_TRUE;
     59:     while (match) {
     60:       char buf = '\0';
     61:       PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     62:       PetscStrncmp(line, "comment", PETSC_MAX_PATH_LEN, &match);
     63:       if (match) while (buf != '\n') PetscViewerRead(viewer, &buf, 1, NULL, PETSC_CHAR);
     64:     }
     65:     /* Read vertex information */
     66:     PetscStrncmp(line, "element", PETSC_MAX_PATH_LEN, &match);
     68:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     69:     PetscStrncmp(line, "vertex", PETSC_MAX_PATH_LEN, &match);
     71:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     72:     snum = sscanf(line, "%d", &Nv);
     74:     match = PETSC_TRUE;
     75:     while (match) {
     76:       PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
     77:       PetscStrncmp(line, "property", PETSC_MAX_PATH_LEN, &match);
     78:       if (match) {
     79:         PetscBool matchB;

     81:         PetscViewerRead(viewer, line, 2, NULL, PETSC_STRING);
     83:         snum = sscanf(line, "%s %s", ntype, name);
     85:         PetscStrncmp(ntype, "float32", 16, &matchB);
     86:         if (matchB) {
     87:           vtype[Nvp] = 'f';
     88:         } else {
     89:           PetscStrncmp(ntype, "int32", 16, &matchB);
     90:           if (matchB) {
     91:             vtype[Nvp] = 'd';
     92:           } else {
     93:             PetscStrncmp(ntype, "uint8", 16, &matchB);
     94:             if (matchB) {
     95:               vtype[Nvp] = 'c';
     96:             } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unable to parse type in PLY file header: %s", line);
     97:           }
     98:         }
     99:         PetscStrncmp(name, "x", 16, &matchB);
    100:         if (matchB) {xi = Nvp;}
    101:         PetscStrncmp(name, "y", 16, &matchB);
    102:         if (matchB) {yi = Nvp;}
    103:         PetscStrncmp(name, "z", 16, &matchB);
    104:         if (matchB) {zi = Nvp;}
    105:         ++Nvp;
    106:       }
    107:     }
    108:     /* Read cell information */
    109:     PetscStrncmp(line, "element", PETSC_MAX_PATH_LEN, &match);
    111:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
    112:     PetscStrncmp(line, "face", PETSC_MAX_PATH_LEN, &match);
    114:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
    115:     snum = sscanf(line, "%d", &Nc);
    117:     PetscViewerRead(viewer, line, 5, NULL, PETSC_STRING);
    118:     snum = sscanf(line, "property list %s %s %s", ntype, itype, name);
    120:     PetscStrncmp(ntype, "uint8", 1024, &match);
    122:     PetscStrncmp(name, "vertex_indices", 1024, &match);
    124:     /* Header should terminate */
    125:     PetscViewerRead(viewer, line, 1, NULL, PETSC_STRING);
    126:     PetscStrncmp(line, "end_header", PETSC_MAX_PATH_LEN, &match);
    128:   } else {
    129:     Nc = Nv = 0;
    130:   }
    131:   DMCreate(comm, dm);
    132:   DMSetType(*dm, DMPLEX);
    133:   DMPlexSetChart(*dm, 0, Nc+Nv);
    134:   DMSetDimension(*dm, dim);
    135:   DMSetCoordinateDim(*dm, cdim);
    136:   /* Read coordinates */
    137:   DMGetCoordinateSection(*dm, &coordSection);
    138:   PetscSectionSetNumFields(coordSection, 1);
    139:   PetscSectionSetFieldComponents(coordSection, 0, cdim);
    140:   PetscSectionSetChart(coordSection, Nc, Nc + Nv);
    141:   for (v = Nc; v < Nc+Nv; ++v) {
    142:     PetscSectionSetDof(coordSection, v, cdim);
    143:     PetscSectionSetFieldDof(coordSection, v, 0, cdim);
    144:   }
    145:   PetscSectionSetUp(coordSection);
    146:   PetscSectionGetStorageSize(coordSection, &coordSize);
    147:   VecCreate(PETSC_COMM_SELF, &coordinates);
    148:   PetscObjectSetName((PetscObject) coordinates, "coordinates");
    149:   VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);
    150:   VecSetBlockSize(coordinates, cdim);
    151:   VecSetType(coordinates, VECSTANDARD);
    152:   VecGetArray(coordinates, &coords);
    153:   if (rank == 0) {
    154:     float rbuf[1];
    155:     int   ibuf[1];

    157:     for (v = 0; v < Nv; ++v) {
    158:       for (p = 0; p < Nvp; ++p) {
    159:         if (vtype[p] == 'f') {
    160:           PetscViewerRead(viewer, &rbuf, 1, NULL, PETSC_FLOAT);
    161:           if (byteSwap) PetscByteSwap(&rbuf, PETSC_FLOAT, 1);
    162:           if      (p == xi) coords[v*cdim+0] = rbuf[0];
    163:           else if (p == yi) coords[v*cdim+1] = rbuf[0];
    164:           else if (p == zi) coords[v*cdim+2] = rbuf[0];
    165:         } else if (vtype[p] == 'd') {
    166:           PetscViewerRead(viewer, &ibuf, 1, NULL, PETSC_INT);
    167:           if (byteSwap) PetscByteSwap(&ibuf, PETSC_INT, 1);
    168:         } else if (vtype[p] == 'c') {
    169:           PetscViewerRead(viewer, &ibuf, 1, NULL, PETSC_CHAR);
    170:         } else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Invalid vertex property type in PLY file");
    171:       }
    172:     }
    173:   }
    174:   VecRestoreArray(coordinates, &coords);
    175:   DMSetCoordinatesLocal(*dm, coordinates);
    176:   VecDestroy(&coordinates);
    177:   /* Read topology */
    178:   if (rank == 0) {
    179:     char     ibuf[1];
    180:     PetscInt vbuf[16], corners;

    182:     /* Assume same cells */
    183:     PetscViewerRead(viewer, &ibuf, 1, NULL, PETSC_CHAR);
    184:     corners = ibuf[0];
    185:     for (c = 0; c < Nc; ++c) DMPlexSetConeSize(*dm, c, corners);
    186:     DMSetUp(*dm);
    187:     for (c = 0; c < Nc; ++c) {
    188:       if (c > 0) {
    189:         PetscViewerRead(viewer, &ibuf, 1, NULL, PETSC_CHAR);
    190:       }
    192:       PetscViewerRead(viewer, &vbuf, ibuf[0], NULL, PETSC_INT);
    193:       if (byteSwap) PetscByteSwap(&vbuf, PETSC_INT, ibuf[0]);
    194:       for (v = 0; v < ibuf[0]; ++v) vbuf[v] += Nc;
    195:       DMPlexSetCone(*dm, c, vbuf);
    196:     }
    197:   }
    198:   DMPlexSymmetrize(*dm);
    199:   DMPlexStratify(*dm);
    200:   PetscViewerDestroy(&viewer);
    201:   if (interpolate) {
    202:     DM idm;

    204:     DMPlexInterpolate(*dm, &idm);
    205:     DMDestroy(dm);
    206:     *dm  = idm;
    207:   }
    208:   return 0;
    209: }