pf-perlin

N-Dimensional Perlin Noise Generator - A Perlin Noise generator for any number of dimensions.

Examples

// Require the module to use it.
var perlin = require('pf-perlin');

// Create a 3D Perlin Noise generator.
var Perlin3D = perlin({dimensions: 3});

// Use it to make a 100x100x100 grid of values
var res = 100, data = [];
for (var i = 0; i < res; ++i) {
  var yData = [];
  for (var j = 0; j < res; ++j) {
    var zData = [];
    for (var k = 0; k < res; ++k) {
      zData.push(Perlin3D.get(i/res, j/res, k/res));
    }
    yData.push(zData);
  }
  data.push(yData);
}

See examples/index.html for a 4-dimensional usage. To build it, run

npm install browserify -g
npm run build

API

perlin(options)

• options (Object) - Optional. An object of options
  • seed (Mixed) - Default: null. The RNG's seed
  • dimensions (Number) - Default: 2. Number of dimensions
  • min (Number) - Default: 0. The minimum value returned
  • max (Number) - Default: 1. The maximum value returned
  • wavelength (Number) - Default: 1. Size of the largest octave
  • octaves (Number) - Default: 8. How many octaves to sample
  • octaveScale (Number) - Default: 1/2. Scaling for successive octaves
  • persistence (Number) - Default: 1/2. Value weighting for successive octaves
  • interpolation (Function) - Default: cosine. Interpolation function used

seed is expected to be a String, but will be passed through JSON.stringify() if it is not. Note that even with the same seed, a different order of perlin.get() calls will change the overall noise function since its values are generated lazily.

wavelength sets the size of the first octave, and each successive octave will be octaveScale times the previous. The octaves are centered about the origin, and added together according to their weight. The first octave has a weight of 1, and each successive octave will be persistence times the previous.

The octaves are sampled using the interpolation function with signature function(a, b, t) that returns a value between a and b according to the parameter 0 <= t <= 1. The default interpolation function used is cosine interpolation.

interpolation: function(a, b, t) {
  return (1-Math.cos(Math.PI*t))/2 * (b-a) + a;
}

After the octaves are sampled and added together, the values are adjusted to fall between min and max. Note that the value distribution is roughly Gaussian.

• returns (Object) - An object with a single function get(). This function accepts either the coordinates as parameters get(x, y, z) or an array of coordinates get([x, y, z]). This object does not store any returned values.