open-simplex-noise

OpenSimplex Noise

TypeScript implementation of OpenSimplex noise.

• JSR package: @joshforisha/open-simplex-noise
• NPM package: open-simplex-noise

Example

import { makeNoise2D } from "open-simplex-noise";
// import { makeNoise2D } from "jsr:@joshforisha/open-simplex-noise"

const [width, height] = [888, 222];
const canvas = document.querySelector("canvas");
const ctx = canvas.getContext("2d");
const imageData = ctx.createImageData(width, height);
const noise2D = makeNoise2D(Date.now()); // Using current date as seed

for (let x = 0; x < width; x++) {
  for (let y = 0; y < height; y++) {
    const i = (x + y * width) * 4;
    const value = (noise2D(x, y) + 1) * 128;
    imageData.data[i] = value;
    imageData.data[i + 1] = value;
    imageData.data[i + 2] = value;
    imageData.data[i + 3] = 255;
  }
}
ctx.putImageData(imageData, 0, 0);

Fractal Noise

For fractal noise results, which typically involves scaling frequencies and stacking octaves, see joshforisha/fractal-noise (JSR: @joshforisha/fractal-noise, NPM: fractal-noise). The functions there can be used with this library's noise algorithm to obtain varied results like the following:

API

Each noise function returns a float between -1 and 1, exclusive: (-1.0, 1.0).

type Noise2D = (x: number, y: number) => number;
type Noise3D = (x: number, y: number, z: number) => number;
type Noise4D = (x: number, y: number, z: number, w: number) => number;

makeNoise2D (seed: number) => Noise2D

Initializes and returns a function to generate 2D noise.

makeNoise3D (seed: number) => Noise3D

Initializes and returns a function to generate 3D noise.

makeNoise4D (seed: number) => Noise4D

Initializes and returns a function to generate 4D noise.