bugs.js

var neopixelWrite = require('ESP8266').neopixelWrite;
var count = 120;
var pixels = new Uint8Array(count * 3);
function update() {
  neopixelWrite(14, pixels);
}
function dampen(p) {
  var i = (p % count) * 3;
  pixels[i]>>>=1;
  pixels[++i]>>>=1;
  pixels[++i]>>>=1;
}
function rgb(p, r, g, b) {
  var i = (p % count) * 3;
  pixels[i] = g;
  pixels[++i] = r;
  pixels[++i] = b;
}
function hue(p, h, d) {
  h = h % 768;
  d = d || 0;
  if (h < 256) return rgb(p, h >> d, (255-h) >> d, 0);
  if (h < 512) return rgb(p, (511-h)>>d,0,(h-256)>>d);
  return rgb(p, 0, (h-512)>>d, (767-h)>>d);
}
function rand(x) {
  return Math.floor(Math.random() * x);
}
var bugs = [];
function Bug() {
  var p, h, l, d;
  function init() {
    p = rand(count);
    h = rand(768);
    l = rand(50) + 50;
    d = rand(2) * 2 - 1;
  }
  function update() {
    for (var i = 0; i < 6; i++) {
      dampen(p + count - i);
    }
    p = (p + d + count) % count;
    hue(p, h, 2);
    h =(h + 1) % 768;
    if (!(--l)) {
      for (i = 1; i < 16; i++) {
        h += 27;
        hue(p + i, h, i >> 1);
        hue(p + count - i, h, i >> 1);
      }
      init();
    }
  }
  init();
  bugs.push(update);
}

for (var i = 0; i < 5; i++) Bug();

var x = 0;
setInterval(function () {
  for (var i = 0; i < 2; i++) {
    x = (x + 1) % bugs.length;
    bugs[x]();
  }
  update();
}, 33);