Isosurface extraction¶

`ferreus_rmt.build_isosurface(seed_points, extents, resolution, isovalue, surface_fn, *, gradient_fn=None, cluster_method=ClusterMethod.CurvatureWeighted, boundary_closure=BoundaryClosure.None_, progress_callback=None)` ¶

Extract an isosurface using regularised marching tetrahedra.

Parameters:

Name	Type	Description	Default
`seed_points`	`NDArray[float64]`	Numpy array of points of shape (N, 3), where N is the number of seed points used to initialise the surface-following extraction.	required
`extents`	`NDArray[float64]`	Axis-aligned bounding box limiting the extracted mesh, with shape (6,) and order [xmin, ymin, zmin, xmax, ymax, zmax].	required
`resolution`	`float`	Sampling resolution used by the extraction lattice.	required
`isovalue`	`float`	The value at which to extract the isosurface.	required
`surface_fn`	`Callable[[NDArray[float64]], NDArray[float64]]`	Callable function to evaluate lattice sample points during isosurface extraction. Must take in a 2D numpy array of float64 3D point coordinates of shape (N, 3) and return a float64 values array of shape (N,) or (N, 1), where N is the number of points being evaluated. Single-column scalar values are returned to Python as shape (N,).	required
`gradient_fn`	`Callable \| None`	Optional callable function to evaluate values and gradients for seed projection. Values may have shape (N,) or (N, 1); gradients must have shape (N, 3).	`None`
`cluster_method`	`ClusterMethod`	`ClusterMethod` used to combine local vertex candidates.	`CurvatureWeighted`
`boundary_closure`	`BoundaryClosure`	`BoundaryClosure` mode for the extracted mesh.	`None_`
`progress_callback`	`Progress \| None`	Optional callback for reporting extraction progress.	`None`

Returns:

Type	Description
`Mesh`	Extracted triangle mesh.

Convenience wrapper for build_isosurface that can extract multiple meshes from a list of isovalues at once.

Parameters:

Name	Type	Description	Default
`seed_points`	`NDArray[float64]`	Numpy array of points of shape (N, 3), where N is the number of seed points used to initialise the surface-following extraction.	required
`extents`	`NDArray[float64]`	Axis-aligned bounding box limiting the extracted mesh, with shape (6,) and order [xmin, ymin, zmin, xmax, ymax, zmax].	required
`resolution`	`float`	Sampling resolution used by the extraction lattice.	required
`isovalues`	`list[float]`	List of values at which to extract isosurfaces.	required
`surface_fn`	`Callable[[NDArray[float64]], NDArray[float64]]`	Callable function to evaluate lattice sample points during isosurface extraction. Must take in a 2D numpy array of float64 3D point coordinates of shape (N, 3) and return a float64 values array of shape (N,) or (N, 1), where N is the number of points being evaluated. Single-column scalar values are returned to Python as shape (N,).	required
`gradient_fn`	`Callable \| None`	Optional callable function to evaluate values and gradients for seed projection. Values may have shape (N,) or (N, 1); gradients must have shape (N, 3).	`None`
`cluster_method`	`ClusterMethod`	`ClusterMethod` to use. If not provided, `CurvatureWeighted` will be used.	`CurvatureWeighted`
`boundary_closure`	`BoundaryClosure \| None_`	`BoundaryClosure` mode to use. If `None_`, leaves clipped boundaries open.	`None_`
`progress_callback`	`Progress \| None`	Optional callback for reporting extraction progress.	`None`

Returns:

Type	Description
`list[Mesh]`	Extracted triangle mesh.