NAME
msh2geo - convert gmsh mesh in geo format (rheolef-7.2)
SYNOPSIS
msh2geo
[-zr|-rz] < file[.msh] > output.geo
msh2geo [-zr|-rz] file[.msh] > output.geo
DESCRIPTION
Convert a .msh file, as generated by the gmsh mesh generator, into a .geo one for Rheolef. The output goes to standard output. The input comes either from standard input or from a file.
EXAMPLES
gmsh -2
toto.mshcad -o toto.msh
msh2geo < toto.msh > toto.geo
gmsh -2 -order
2 toto.mshcad -o toto2.msh
msh2geo < toto2.msh > toto2.geo
See the gmsh documentation for a detailed description of the .mshcad input file for gmsh.
OPTIONS
-cartesian
-rz
-zr
Specifies the coordinate system. The default is cartesian while -rz and -zr denotes some axisymmetric coordinate systems. Recall that most of Rheolef codes are coordinate-system independent and the coordinate system is specified in the geometry file .geo.
IMPLEMENTATION NOTES
There is an issue for curved boundaries, using high order Pk polynomial elements. Pk triangle, when k>=5, may have internal nodes renumbered. From the gmsh documentation:
The nodes of a curved element are numbered in the following order:
the element
principal vertices;
the internal nodes for each edge;
the internal nodes for each face;
the volume internal nodes.
The numbering
for face and volume internal nodes is recursive,
i.e., the numbering follows that of the nodes of an embedded
face/volume.
The higher order nodes are assumed to be equispaced on the
element.
In Rheolef, internal triangle nodes are numbered from left to right and then from bottom to top. The numbering differ for triangle when k >= 5. Thus, msh2geo fixes the corresponding internal nodes numbering during the conversion.
Pk tetrahedrons and hexahedrons in gmsh and Rheolef has not the same edge-node order and orientation. E.g. for tetrahedrons, edges 13 and 23 should be swapped and reoriented as 32 and 31. Thus, msh2geo also fix the corresponding internal nodes numbering.
TODO
Fix for P3-tetra: swap edges orientations for 3,4,5 and swap faces 1 and 2. Check P4(T) for face orientation. Perform face visualization with gnuplot face fill.
See also hexa edges orient and faces numbers and orient.
Check that node are numbered by vertex-node, then edge-node, then face(tri,qua)-node and then volume(T,P,H)-node. Otherwise, renumber all nodes.
Support for high order >= 6 element is not documented in gmsh, but gmsh supports it at run
IMPLEMENTATION
This documentation has been generated from file main/sbin/msh2geo.cc
AUTHOR
Pierre Saramito <Pierre.Saramito [AT] imag.fr>
COPYRIGHT
Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito [AT] imag.fr> GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>;. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.