Perlin noise for Norns

naus3a · August 20, 2020, 5:21pm

Even if I’ve been randomly orbiting near this forum for years, here I am posting for the first time, after a few weeks from when I brought home my Norns DIY shield.

More often than not, when I need to become friend with a new language/platform/environment, I find myself implementing Perlin noise for it and Norns was no exception; while this kind of noise is more popular in a visual context, it can be easily used slowly move synth parameters in an organic, never repeating way, similar to modules like Nonlinearcircuits’ Sloth, or MTM’s Turing machine.
The code is very much a WIP (read: it probably has bugs), but - in case anybody wants to play with it -, here it is:

github.com

naus3a/NauNorns/blob/master/lib/noise.lua

-- Perlin noise for norns
-- author: @naus3a - naus3a@gmail.com

--[[ Credits:
      this Perlin noise implementation is basically a lua port of Stefan Gustavon's SimplexNoise1234 c++ version. 
      I like this code a lot, I used it very often and I ported it to most languages/environments, so kudos and credits to:
      (c) Stefan Gustavson 2003-2005
      stegu@itn.liu.se
]]--

Noise = {}

-- Permutation table
-- This is just a random jumble of all numbers 0-255,
-- repeated twice to avoid wrapping the index at 255 for each lookup.
-- This needs to be exactly the same for all instances on all platforms,
-- so it's easiest to just keep it as inline explicit data.
-- This also removes the need for any initialisation of this class.
Noise.perm = {151,160,137,91,90,15,
  131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,

This file has been truncated. show original

Also, here’s some noise visualized on the Norns’ screen:

Olivier · August 20, 2020, 5:43pm

Love it – was just reading up on perlin noise in the context of p5.js/processing last week, and my first thought was how it might be ported to norns. Thanks for sharing this, and – I guess, officially – welcome!

naus3a · August 20, 2020, 5:47pm

Thanks!
It’s been a while since the last time I looked into the P5 codebase, but I think this is the same approach they use; I know for sure it’s the same you fine in OpenFrameworks, which is basically my swiss army knife for anything generative

toneburst · August 20, 2020, 6:34pm

This is great!!

I’ve been meaning to do something with Perlin Noise since my days hacking GLSL shaders in Quartz Composer.

Looking forward to giving this a go!