Geometrical tools

import mefikit as mf
import numpy as np
import pyvista as pv

pv.set_plot_theme("dark")
pv.set_jupyter_backend("static")

Snap points

x = np.linspace(0.0, 3.0, 10, endpoint=True)
mesh = mf.build_cmesh(x, x)

eps = 0.1
dec = x[-1] / len(x) + eps
x2 = np.linspace(dec, x[-1] + dec, len(x), endpoint=True)
mesh2 = mf.build_cmesh(x2, x2)

Note: epsilon value used in the following operation is big enough so that there are multiple candidates for some points, but low enough so that there is no degenerated cell created.

snaped = mesh.snap(mesh2, eps=x[-1] / len(x))

pt = pv.Plotter()
pt.add_mesh(mesh.descend().to_pyvista())
pt.add_mesh(mesh2.descend(target_dim=0).to_pyvista())
pt.show(cpos="xy")

pt = pv.Plotter()
pt.add_mesh(snaped.to_pyvista(), show_edges=True)
pt.add_mesh(mesh2.descend(target_dim=0).to_pyvista())
pt.show(cpos="xy")

Merge nodes

x = range(2)
y = np.linspace(0.0, 3.0, 3, endpoint=True)
z = np.logspace(0.0, 1.0, 3, endpoint=True)
volumes = mf.build_cmesh(x, y, z)
faces = volumes.descend()
cracked = volumes.crack(faces)

merged = cracked.merge_nodes()

edges = faces.descend()
compos_merged = merged.connected_components()
compos_cracked = cracked.connected_components()

assert len(compos_merged) == 1

n_compos = len(compos_cracked)

shape = (3, n_compos + 1)
groups = [
    (0, np.s_[:-1]),  # cracked
    (0, n_compos),  # merged
    (1, np.s_[:-1]),  # cracked txt
    (np.s_[1:], n_compos),  # merged compos
    *((2, i) for i in range(n_compos)),  # cracked compos
]
row_weights = [1.0, 0.1, 1.0]
col_weights = [*(0.5,) * n_compos, 1.5]
pv.set_jupyter_backend("static")
plotter = pv.Plotter(
    shape=shape, groups=groups, row_weights=row_weights, col_weights=col_weights
)

plotter.subplot(0, n_compos)
plotter.add_text("Merged mesh")
plotter.add_mesh(merged.to_pyvista(), show_edges=True)
plotter.subplot(0, 0)
plotter.add_text("Cut mesh used for the crack")
plotter.add_mesh(faces.to_pyvista().shrink(0.8), show_edges=True)

plotter.subplot(1, n_compos)
plotter.add_text("Compo of merged mesh")
plotter.add_mesh(edges.to_pyvista())
plotter.add_mesh(compos_merged[0].to_pyvista(), show_edges=True)

plotter.subplot(1, 0)
plotter.add_text("Compos of cracked mesh")

for i, compo in enumerate(compos_cracked):
    plotter.subplot(2, i)
    plotter.add_mesh(edges.to_pyvista())
    plotter.add_mesh(compo.to_pyvista(), show_edges=True)
    plotter.camera.zoom(2)
plotter.show()