Sample Function: Perlin Noise in 3D

Here we use pyvista.core.utilities.features.sample_function() to sample Perlin noise over a region to generate random terrain.

Video games like Minecraft use Perlin noise to create terrain. Here, we create a voxelized mesh similar to a Minecraft “cave”.

import pyvista as pv

Generate Perlin Noise over a 3D StructuredGrid

Feel free to change the values of freq to change the shape of the “caves”. For example, lowering the frequency will make the caves larger and more expansive, while a higher frequency in any direction will make the caves appear more “vein-like” and less open.

Change the threshold to reduce or increase the percent of the terrain that is open or closed

freq = (1, 1, 1)
noise = pv.perlin_noise(1, freq, (0, 0, 0))
grid = pv.sample_function(noise, [0, 3.0, -0, 1.0, 0, 1.0], dim=(120, 40, 40))
out = grid.threshold(0.02)
out

Header	Data Arrays
UnstructuredGrid Information N Cells 109863 N Points 121638 X Bounds 0.000e+00, 3.000e+00 Y Bounds 0.000e+00, 1.000e+00 Z Bounds 0.000e+00, 1.000e+00 N Arrays 1	Name Field Type N Comp Min Max scalars Points float64 1 -6.143e-02 9.082e-01

color limits without blue

mn, mx = [out['scalars'].min(), out['scalars'].max()]
clim = (mn, mx * 1.8)

out.plot(
    cmap='gist_earth_r',
    background='white',
    show_scalar_bar=False,
    lighting=True,
    clim=clim,
    show_edges=False,
)