NAME

       msh2geo - convert gmsh mesh in geo format

SYNOPSIS

         msh2geo [-zr|-rz] input[.msh] > output.geo

DESCRIPTION

       Convert  a gmsh `.msh' into `.geo' one.  The output goes to standart output.  See the gmsh
       documentation for a detailed description of the `.mshcad' input file for gmsh.

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

COORDINATE SYSTEM OPTION

       Most of rheolef  codes  are  coordinate-system  independant.   The  coordinate  system  is
       specified in the geometry file `.geo'.

       -zr

       -rz    the  2d  mesh is axisymmetric: zr (resp. rz) stands when the symmetry is related to
              the first (resp. second) coordinate.

NOTES

       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  fix the
       corresponding internal nodes numbering during the conversion.

       Pk tetrahedrons and hexaedrons in gmsh and rheolef has not the  same  edge-node  order  nd
       orientation.  E.g. for tetrahedrons, edges 13 and 23 should be swaped and reoriented as 32
       and 31.  Thus, msh2geo 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 visualisation 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 ? not documented in gmsh, but gmsh supports it at run