NAME

       msh2geo - convert gmsh mesh in geo format (rheolef-7.1)

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@imag.fr>

COPYRIGHT

       Copyright   (C)  2000-2018  Pierre  Saramito  <Pierre.Saramito@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.