fem.gmsh.gmsh_topology

fem.gmsh.gmsh_topology(
    geometry,
    *,
    geometry_format='step',
    target_size,
    order=2,
    algorithm=HXT,
    optimize=True,
    classify_angle=CLASSIFY_ANGLE,
    verbose=False,
)

Mesh a solid with Gmsh — the whole of the opaque part, and no more.

Nothing here knows about patches. What comes back is what Gmsh alone can say: node positions, cells, and which entity owns each node, expressed as the surface tags whose closure the node lies on (:func:assign_ownership is what turns those into patches). Keeping the cut here is what lets the mesher live behind a Tesseract — a container can be handed a file and cannot be handed a scene, whose patch fields are live Python callables.

Parameters

Name	Type	Description	Default
geometry	str	The file’s contents (ASCII): a STEP solid, or the dual-contour surface as STL (:func:`surface_stl`).	required
geometry_format	str	`"step"` or `"stl"`.	`'step'`
target_size	float	Uniform element size in the file’s own units.	required
order	int	1 for TET4, 2 for TET10.	`2`
algorithm	int	Gmsh’s `Mesh.Algorithm3D`; :data:`HXT` by default.	`HXT`
optimize	bool	Run Gmsh’s tet optimizer after generation.	`True`
classify_angle	float	STL only — see :data:`CLASSIFY_ANGLE`.	`CLASSIFY_ANGLE`
verbose	bool	Let Gmsh write to the terminal.	`False`

Returns

Name	Type	Description
	dict[str, Any]	`points` `(n, 3)`, `cells` `(t, 4\\|10)` in meshio order, `entity_dim` `(n,)`, `bounding_surfaces` `(n, k)` of surface tags (`-1` padded), `num_surface`, `num_corner_points`, `edge_parents` (`None` at order 1), `bounds` `(2, 3)`, `cad_entities`, and the timings.

Raises

Name	Type	Description
	ImportError	If the `gmsh` extra is not installed.
	RuntimeError	If the geometry carries no solid, or Gmsh makes no tets.
	ValueError	If `order` is not 1 or 2, or the format is unknown.