simplex-noise.js

API Documentation

simplex-noise.js is a simplex noise implementation in Javascript/TypeScript. It works in the browser and nodejs. Using Commonjs and ES Modules. It is self contained (dependency free), relatively small (about 2k minified and gzipped) and fairly fast (about 20 nanoseconds for a sample of 2d noise).

Demos

Simple 2D plasma on codepen.io.
3D voxel world generation example.
Film grain in analog film emulator.

Created something awesome with simplex-noise? Let me know so I can add it to the list.

Installation

npm i -S simplex-noise

Usage

// when using es modules
import SimplexNoise from 'simplex-noise';
// when using commonjs
const {SimplexNoise} = require('simplex-noise');

By default simplex-noise.js will use Math.random() to seed the noise.

// initializing a new simplex instance
// do this only once as it is relatively expensive
const simplex = new SimplexNoise(),
    value2d = simplex.noise2D(x, y),
    value3d = simplex.noise3D(x, y, z),
    value4d = simplex.noise4D(x, y, z, w);

You can also pass in a seed string which will then be used to initialize the noise using the built in alea PRNG.

const simplex = new SimplexNoise('seed'),
    value2d = simplex.noise2D(x, y),
    sameSeed = new SimplexNoise('seed'),
    differentSeed = new SimplexNoise('different seed');

sameSeed.noise2D(x, y) === value2d
differentSeed.noise2D(x, y) !== value2d

You can also pass an alternative random function to the constructor that is used to build the permutation table. This can be used with a custom pseudo random number generator:

const random = new Alea(seed),
    simplex = new SimplexNoise(random),
    value2d = simplex.noise2D(x, y);

The ALEA PRNG can be found in the npm package alea.

node.js

Node.js is also supported, you can install the package using npm.

const SimplexNoise = require('simplex-noise'),
    simplex = new SimplexNoise(Math.random),
    value2d = simplex.noise2D(x, y);

Benchmarks

simplex-noise.js is reasonably quick. According to perf/benchmark.js I can perform about 50 million noise2D() calls/second on a single thread on my desktop (Ryzen 5950X). So ~20 nanoseconds per call.

$ node perf/index.js
27745787.933336906
init: 192,590 ops/sec ±1%
noise2D: 57,928,891 ops/sec ±1%
noise3D: 34,159,230 ops/sec ±0%
noise4D: 24,589,786 ops/sec ±0%

At least at a glance it also seems to be faster than 'fast-simplex-noise':

simplex-noise noise2D: 53,429,815 ops/sec ±0%
fast-simplex-noise noise2D: 6,239,845 ops/sec ±0%

simplex-noise noise4D: 22,578,593 ops/sec ±0%
fast-simplex-noise noise4D: 5,292,975 ops/sec ±0%

Tests

There are some simple unit tests for this library to run them

npm install && npm test

Changelog

3.0.1

Include simplex-noise.ts as source file, fixes sourcemap warnings.

3.0.0

Changed module structure. When using bundlers that import the es module even using require() the import might need to be updated.
Dependency update
Setting sideEffects: false in package.json
Added snapshot tests
Code converted to typescript, the package can of course still be used from regular JS
Dropped bower
Added support for es modules

2.4.0

Included a PRNG based on ALEA to directly allow seeding
Included typescript definitions

2.3.0

⚠️ This release changes the output of the noise functions. ⚠️

In the future such changes will be released as a new major version.

Corrected generation of permutation table
Moved tests to mocha/chai
Cleanup

2.2.0

Small performance improvement for 2D noise

2.1.1

Increased entropy by fixing a little initialization issue.

2.1.0

AMD support

2.0.0

Changed node.js api, SimplexNoise is now exported directly.
Added unit tests

1.0.0

Initial Release

Requirements

It requires typed arrays. If you want to use it in browsers without support you will need to use a polyfill like typedarray.js.

License

Credits

This is mostly a direct javascript port of the Java implementation by Stefan Gustavson and Peter Eastman.

The integrated pseudo random generator is based on code by by Johannes Baagøe.

The initial typescript definition has been provided by Neonit.

MAKIO135 / sn