https://www.npmjs.com/package/alea is tiny and could probably be leveraged inside of simplex-noise.

This would be valuable because other parts of my simulation rely on alea, and if simplex-noise is pulling this in as a dependency I'll have less duplicated code.

@jwagner would you be open to a PR for this? I'm happy to submit one.

Factored out gradient look up and applied Gustavson's corrections. Minor pre calculation tweaks. Comments and references are in the code, still needs to be cleaned up.

Release plan

• [x] Finish writing article
• [x] Finish demo
• [x] Release docs
• [x] Merge this branch & Trigger NPM Release
• [x] Release synth wave demo to 29a.ch
• [x] Make synth wave demo repo public
• [x] Fix up code pens
• [x] Publish article & update on 29a.ch
• [x] Announce new version (twitter, ?)
• [x] Clean up related issues & PRs

Hi there,

Thanks for putting this awesome resource out there. I was hoping to use the 3.0.1 version in codepen but getting a MIME type ('application/octet-stream'). Here's the link. Version 2.4.0 seems to work fine, given a nearly identical implementation.

x | 0 does exactly the same as Math.floor(x) but much faster. Don't know why you got ~10% speedup by combining both approaches, but definitely it would be even faster without calling Math.floor at all.

What

Forgive me if I'm wrong but I am using this package in a create-react-app 5.0.0 and React 17.X.X setting and with simplex-noise 3.0.0 I recieve this error.

WARNING in ./node_modules/simplex-noise/dist/esm/simplex-noise.js
Module Warning (from ./node_modules/source-map-loader/dist/cjs.js):
Failed to parse source map from '/Users/matt-jarrett/Developer/js-pollock/node_modules/simplex-noise/simplex-noise.ts' file: Error: ENOENT: no such file or directory, open '/Users/matt-jarrett/Developer/js-pollock/node_modules/simplex-noise/simplex-noise.ts'
 @ ./src/lib/create-renderer.js 6:0-41 15:22-34
 @ ./src/lib/index.js 8:0-50 28:25-39
 @ ./src/App.js 13:0-25 87:39-42
 @ ./src/index.js 8:0-27 11:38-41

1 warning has detailed information that is not shown.
Use 'stats.errorDetails: true' resp. '--stats-error-details' to show it.

webpack 5.65.0 compiled with 1 warning in 1864 ms

My use

import SimplexNoise from "simplex-noise"
...
export default (opt = {}) => {
  ...
  const simplex = new SimplexNoise(randFunc)
  ...
}

Am I doing something wrong?

I searched for simplex-noise.ts as it's referenced in the error and I see it in this package's package.json.

...
"source": "simplex-noise.ts",
...

a number of changes:

• replace the alea internal implementation with the one in npm
• convert the module from UMD to a pure es module (API Breaking change)
• remove bower package
• update all dependencies
• use let and const instead of var everywhere
• update travis ci to test against maintained node versions (10 through 14)
• style change: function() -> function ()

hello friend,

i wanted to load simplex-noise as a hip new web-ready es module

i created this branch and also published [email protected] to npm for my own usage

the es module is available now via cdn here: https://unpkg.com/[email protected]/dist-esm/simplex-noise.js

i used babel-plugin-transform-commonjs to generate the es module distribution

codepen example demonstrates loading simplex-noise-esm as an es module

Feature request

Move the following into a SimplexNoise.init() (or other name) method: https://github.com/jwagner/simplex-noise.js/blob/37b3125a48ec3347c7a66d6e12ce2e78447ada99/simplex-noise.ts#L80-L87

Use case

When updating the random number generator, we are forced to recreate an instance of SimplexNoise. With this, we could create a single instance and reinit it if the PRNG changed:

// Use default Math.random (non predictable)
let simplex = new SimplexNoise(Math.random);

function setSeed(s) {
  // Update seed to make Math.random predictable
  seedMathRandom(s)
  
  // Before:
  // Recreate noise instance
  simplex = new SimplexNoise(Math.random);

  // After proposed change:
  // Reset permutation table
  simplex.init(Math.random);
}

setSeed('0')

Let me know how that sounds and if you need a PR.

Whenever I build dev or build in sapper, rollup-plugin-svelte shows this warning.

[rollup-plugin-svelte] The following packages did not export their `package.json` file so we could not check the "svelte" field. If you had difficulties importing svelte components from a package, then please contact the author and ask them to export the package.json file.

Just to bring this to your attention, everything still works even though the warning is shown. All builds still are successful and functionality is not affected.

If you set seed to zero or empty string, then SimplexNoise will generate random noise which might not be expected as the seed value was set. Now it will only be random if 'randomOrSeed' not set at all.

Any chance you might add an (optional) way to get analytical derivatives for the noise result?

Derivatives are handy because they tell you the ”slope” of the noise, which is incredibly useful for use cases like terrain generation. It’s possible to manually calculate them by sampling the noise 3+ times, but (as I understand it) analytical derivatives are much cheaper to compute.

As a reference, I’ve found these GLSL implementations:

• https://iquilezles.org/articles/gradientnoise/
• https://github.com/BrianSharpe/Wombat (the _Deriv variants)

I’ve explored adding them myself and making a PR, but honestly I’m a bit out of my depth here. :)

what about a "generic" noise function, with variable-length arguments, ie:

|generic |implied |comment| |-|-|-| |noise()|noise2D(0, 0)| 0 by default| |noise(1)|noise2D(1,1)| same value for 2nd arg| |noise(1,2)|noise2D(1,2)| | |noise(1,2,3)|noise3D(1,2,3)| | |noise(1,2,3,4)|noise4D(1,2,3,4)| | |noise(1,2,3,4,5)|noise4D(1,2,3,4,5)|NB: when more than 4 args => 5th, 6th... will just be ignored by noise4D|

This is inspired from https://processing.org/reference/noise_.html

function noise(...args) {
  let dim // 2 or 3 or 4
  let args2 = [...args] // copy of args
  
  if (args.length < 2) {
    // 0 or 1 arg => noise2d
    const arg = args[0] || 0
    args2 = [arg, arg]
    dim = 2
  } else {
    // 2 or 3 or 4 or more args => noise2D or noise3D or noise4D
    dim = Math.min(args.length, 4)
  }
  
  return simplex[`noise${dim}D`](...args2) /2 + 0.5 // normalize [0;1]
}

NB: I've chosen to normalise the value to ]0;1[ but maybe you prefer staying ]-1;1[

working demo: https://codepen.io/abernier/pen/ExvqNyj

Would you consider supporting dimensions beyond 4D, specifically 5D and 6D?

For me this would simplify use-cases for looping / tiling animations such as #29 which can be implemented by using two of the dimensions to sample along a circle.