perlin_noise#
- perlin_noise(amplitude, freq: Sequence[float], phase: Sequence[float])[source]#
Return the implicit function that implements Perlin noise.
Uses
vtk.vtkPerlinNoise
and computes a Perlin noise field as an implicit function.vtk.vtkPerlinNoise
is a concrete implementation ofvtk.vtkImplicitFunction
. Perlin noise, originally described by Ken Perlin, is a non-periodic and continuous noise function useful for modeling real-world objects.The amplitude and frequency of the noise pattern are adjustable. This implementation of Perlin noise is derived closely from Greg Wardâ€™s version in Graphics Gems II.
- Parameters
- amplitude
float
Amplitude of the noise function.
amplitude
can be negative. The noise function varies randomly between-|Amplitude|
and|Amplitude|
. Therefore the range of values is2*|Amplitude|
large. The initial amplitude is 1.- freq
Sequence
[float
,float
,float
] The frequency, or physical scale, of the noise function (higher is finer scale).
The frequency can be adjusted per axis, or the same for all axes.
- phase
Sequence
[float
,float
,float
] Set/get the phase of the noise function.
This parameter can be used to shift the noise function within space (perhaps to avoid a beat with a noise pattern at another scale). Phase tends to repeat about every unit, so a phase of 0.5 is a half-cycle shift.
- amplitude
- Returns
vtk.vtkPerlinNoise
Instance of
vtk.vtkPerlinNoise
to a Perlin noise field as an implicit function. Use withpyvista.sample_function()
.
Examples
Create a Perlin noise function with an amplitude of 0.1, frequency for all axes of 1, and a phase of 0 for all axes.
>>> import pyvista >>> noise = pyvista.perlin_noise(0.1, (1, 1, 1), (0, 0, 0))
Sample Perlin noise over a structured grid and plot it.
>>> grid = pyvista.sample_function(noise, [0, 5, 0, 5, 0, 5]) >>> grid.plot()