/*@C
DMPlexCreateGmshFromFile - Create a DMPlex mesh from a Gmsh file
+ comm - The MPI communicator
. filename - Name of the Gmsh file
- interpolate - Create faces and edges in the mesh
Output Parameter:
. dm - The DM object representing the mesh
Level: beginner
.seealso: DMPlexCreateFromFile(), DMPlexCreateGmsh(), DMPlexCreate()
@*/
PetscErrorCode DMPlexCreateGmshFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
{
PetscViewer viewer, vheader;
PetscMPIInt rank;
PetscViewerType vtype;
char line[PETSC_MAX_PATH_LEN];
int snum;
PetscBool match;
int fT;
PetscInt fileType;
float version;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = MPI_Comm_rank(comm, &rank);
CHKERRQ(ierr);
/* Determine Gmsh file type (ASCII or binary) from file header */
ierr = PetscViewerCreate(comm, &vheader);
CHKERRQ(ierr);
ierr = PetscViewerSetType(vheader, PETSCVIEWERASCII);
CHKERRQ(ierr);
ierr = PetscViewerFileSetMode(vheader, FILE_MODE_READ);
CHKERRQ(ierr);
ierr = PetscViewerFileSetName(vheader, filename);
CHKERRQ(ierr);
if (!rank) {
/* Read only the first two lines of the Gmsh file */
ierr = PetscViewerRead(vheader, line, 1, NULL, PETSC_STRING);
CHKERRQ(ierr);
ierr = PetscStrncmp(line, "$MeshFormat", PETSC_MAX_PATH_LEN, &match);
CHKERRQ(ierr);
if (!match) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "File is not a valid Gmsh file");
ierr = PetscViewerRead(vheader, line, 2, NULL, PETSC_STRING);
CHKERRQ(ierr);
snum = sscanf(line, "%f %d", &version, &fT);
fileType = (PetscInt) fT;
if (snum != 2) SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Unable to parse Gmsh file header: %s", line);
if (version < 2.0) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Gmsh file must be at least version 2.0");
}
ierr = MPI_Bcast(&fileType, 1, MPIU_INT, 0, comm);
CHKERRQ(ierr);
/* Create appropriate viewer and build plex */
if (fileType == 0) vtype = PETSCVIEWERASCII;
else vtype = PETSCVIEWERBINARY;
ierr = PetscViewerCreate(comm, &viewer);
CHKERRQ(ierr);
ierr = PetscViewerSetType(viewer, vtype);
CHKERRQ(ierr);
ierr = PetscViewerFileSetMode(viewer, FILE_MODE_READ);
CHKERRQ(ierr);
ierr = PetscViewerFileSetName(viewer, filename);
CHKERRQ(ierr);
ierr = DMPlexCreateGmsh(comm, viewer, interpolate, dm);
CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);
CHKERRQ(ierr);
ierr = PetscViewerDestroy(&vheader);
CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PETSC_EXTERN void PETSC_STDCALL dmplexcreategmsh_(MPI_Fint * comm,PetscViewer viewer,PetscBool *interpolate,DM *dm, int *__ierr ){
*__ierr = DMPlexCreateGmsh(
MPI_Comm_f2c( *(comm) ),
(PetscViewer)PetscToPointer((viewer) ),*interpolate,dm);
}
