Boolean Operations

Perform boolean operations with closed surfaces (intersect, cut, etc.).

Boolean/topological operations (intersect, cut, etc.) methods are implemented for pyvista.PolyData mesh types only and are accessible directly from any pyvista.PolyData mesh. Check out pyvista.PolyDataFilters and take a look at the following filters:

• pyvista.PolyDataFilters.boolean_add()

• pyvista.PolyDataFilters.boolean_cut()

• pyvista.PolyDataFilters.boolean_difference()

• pyvista.PolyDataFilters.boolean_union()

For merging, the + operator can be used between any two meshes in PyVista which simply calls the .merge() filter to combine any two meshes. Similarly, the - operator can be used between any two pyvista.PolyData meshes in PyVista to cut the first mesh by the second.

# sphinx_gallery_thumbnail_number = 6
import pyvista as pv
import numpy as np

def make_cube():
    x = np.linspace(-0.5, 0.5, 25)
    grid = pv.StructuredGrid(*np.meshgrid(x, x, x))
    return grid.extract_surface().triangulate()

# Create to example PolyData meshes for boolean operations
sphere = pv.Sphere(radius=0.65, center=(0, 0, 0))
cube = make_cube()

p = pv.Plotter()
p.add_mesh(sphere, color="yellow", opacity=0.5, show_edges=True)
p.add_mesh(cube, color="royalblue", opacity=0.5, show_edges=True)
p.show()

Out:

[(2.5043836950059895, 2.5043836950059895, 2.5043836950059895),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]

Boolean Add

Add all of the two meshes together using the pyvista.PolyDataFilters.boolean_add() filter or the + operator.

Order of operations does not matter for boolean add as the entirety of both meshes are appended together.

add = sphere + cube
add.plot(opacity=0.5, color=True, show_edges=True)

Out:

[(2.5043836950059895, 2.5043836950059895, 2.5043836950059895),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]

Boolean Cut

Perform a boolean cut of a using b with the pyvista.PolyDataFilters.boolean_cut() filter or the - operator since both meshes are pyvista.PolyData.

Order of operations does not matter for boolean cut.

cut = cube - sphere

p = pv.Plotter()
p.add_mesh(cut, opacity=0.5, show_edges=True, color=True)
p.show()

Out:

[(2.5043836950059895, 2.5043836950059895, 2.5043836950059895),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]

Boolean Difference

Combine two meshes and retains only the volume in common between the meshes using the pyvista.PolyDataFilters.boolean_difference() method.

Note that the order of operations for a boolean difference will affect the results.

diff = sphere.boolean_difference(cube)

p = pv.Plotter()
p.add_mesh(diff, opacity=0.5, show_edges=True, color=True)
p.show()

Out:

[(1.9318516525781368, 1.9318516525781368, 1.9318516525781368),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]

diff = cube.boolean_difference(sphere)

p = pv.Plotter()
p.add_mesh(diff, opacity=0.5, show_edges=True, color=True)
p.show()

Out:

[(2.5043836950059895, 2.5043836950059895, 2.5043836950059895),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]

Boolean Union

Combine two meshes and attempts to create a manifold mesh using the pyvista.PolyDataFilters.boolean_union() method.

Order of operations does not matter for boolean union.

union = sphere.boolean_union(cube)

p = pv.Plotter()
p.add_mesh(union,  opacity=0.5, show_edges=True, color=True)
p.show()

Out:

[(1.9318516525781368, 1.9318516525781368, 1.9318516525781368),
 (0.0, 0.0, 0.0),
 (0.0, 0.0, 1.0)]