Mesh/Plane intersection

compas
1

Is there any plan to include a Mesh/Plane intersection, similar to what is possible in GH with an output of a polycurve?

2

there is mesh_cut_by_plane in the core library (however, this function doesn’t return an intersection polygon), but a more robust and much faster version is available in compas_cgal. (https://blockresearchgroup.github.io/compas_cgal/)

the new plugin system will soon allow the CGAL based version to be plugged into core COMPAS and use it from there…

1 Like
3 
from compas.datastructures import Mesh
from compas.geometry import Line, Plane, Vector
from compas.geometry import is_point_on_plane

mesh = Mesh.from_polyhedron(8)
normal = Vector(0, 1, 0)
plane = Plane([0,0,0], normal)
# cut mesh by plane
section1, _ = mesh.cut(plane)

# get intersection line
cut = []
for vert1, vert2 in section1.edges():
    p1, p2 = section1.vertex_coordinates(vert1), section1.vertex_coordinates(vert2)
    if is_point_on_plane(p1, plane) and is_point_on_plane(p2, plane):
        cut.append(Line(p1, p2))

section = Mesh.from_lines(cut)