seamsh.gmsh module

seamsh.gmsh.convert_to_gis(input_filename, projection, output_filename)

Converts a triangular gmsh mesh into shapefile or geopackage.

Parameters:

  • input_filename (str) – any mesh file readable by gmsh (typically a .msh file)

  • projection (SpatialReference) – the projection assigned to the output layer, mesh files do not store any projection so neither checks nor re-projections are performed (if none mesh projection will be used).

  • output_filename (str) – shape file (.shp) or geopackage (.gpkg) file

Return type:

None

seamsh.gmsh.mesh(domain, filename, mesh_size, version=4.1, intermediate_file_name=None, smoothness=0.3, output_srs=None, transfinite_curves={}, quad=False)

Calls gmsh to generate a mesh from a geometry and a mesh size callback

Parameters:

  • domain (Domain) – the input geometry

  • filename (str) – output mesh file (.msh)

  • mesh_size (Callable[[ndarray, SpatialReference], ndarray]) – callbable prescribing the mesh element size

  • version (float) – msh file version (typically 2.0 or 4.0)

  • intermediate_file_name (Optional[str]) – if not None, save intermediate meshes to those files for debugging purpose (suffixes and extensions will be appended), if == “-”, an interactive gmsh graphical window will pop up after each meshing step.

  • smoothness – Maximum gradation of the mesh size, any positive value is valid but a value in the range [0.1,0.5] is recommended.

  • output_srs (Optional[SpatialReference]) – coordinate system of the output file (if None, the coordinate system of the domain is used).

  • tranfinite_curves – dict(str, int) prescribe a fixed number of mesh getElements on curves with given physical tag.

  • quad (bool) – if True, generate quadrangles instead of triangles. This a achieved by generating a quad-dominant mesh and then splitting all elements (quads and triangles) into quads. So the resulting mesh size is half the prescribed one.

Return type:

None

seamsh.gmsh.reproject(input_filename, input_srs, output_filename, output_srs, output_version=4.1)

Change the coordinate of an existing mesh.

Parameters:

  • input_filename (str) – input mesh file (any format readable by gmsh).

  • input_srs (SpatialReference) – coordinate system of the input mesh. If None, the model projection is used.

  • output_filename (str) – output mesh file (.msh)

  • output_srs (SpatialReference) – coordinate system of the output file (if None, the coordinate system of the domain is used).

  • output_version (float) – msh file version (typically 2.0 or 4.0)