basic-flooding.js

var rgb = new Uint8ClampedArray(50 * 3);

// Set the colours of a particular light (i) at a given intensity (s)
function set(r, g, b, i, s){
  i *= 3;
  
  if(i > 0) {
    rgb[i] = rgb[i] + ((r - rgb[i]) * s); i++;
    rgb[i] = rgb[i] + ((g - rgb[i]) * s); i++;
    rgb[i] = rgb[i] + ((b - rgb[i]) * s); i++;
  }

}

// Flood the LEDs with a particular colour
function flood(r,g,b,cb) {
  var p = 0; // the current position of the animation
  var s = 8; // the number of steps it takes to fully change colour
  var interval = setInterval(function() {
    p++;

    // this is the key/cool bit - needs a diagram
    for(var i = 0; i < s; i++) {
      set(r, g, b, p-i, 1/(s-i));
    }

    require("neopixel").write(D1, rgb);

    if((p-s) == rgb.length/3) {
      clearInterval(interval);
      console.log("cleared");
      if(cb) cb();
    }

  }, 50);
}


flood(255,0,0,function(){
  flood(0, 255,150,function(){
    flood(0,0,0);
  });
});