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  <h1>Pls allow the mic... then make some noise</h1>

<div id="screen">


                html {background:#efefef; font-family:"Lato", "Lucida Grande","Lucida Sans Unicode", Tahoma, Sans-Serif; letter-spacing:-0.2px;}
body {margin:0px; padding:0px; overflow:hidden;}
header {
  display:flex; padding:5px;
  h1 {
    display:block; padding:5px 15px;
    border: 3px solid #343436; border-radius: 3px;
    text-align:center; text-decoration:none; color:#fff; font-size:1.1em;
    &:hover {background-color:#4d4d50;}
#screen, canvas {width: 100vw; height: 100vh; padding:0px; margin:0px;}
#screen {
  position: relative;
  background: black;



                // this is all the drawing stuff right here
var shapeCount = 16;

function hex() {
  ctx.fillStyle = "#000";
  ctx.fillRect(0,0,canvas.width, canvas.height);

  var frequencies = adjustFreqData(shapeCount);
  var newData = frequencies.newFreqs;
  ctx.globalCompositeOperation = "hard-light";
   ctx.lineWidth = 4;
  for(var i=0;i<newData.length;i++) {
    var d = newData[i];
    // ctx.beginPath();
    drawHex(ctx, (d*1.5)+20, i*(screen.width/shapeCount), i*(screen.height/shapeCount));
    ctx.strokeStyle = "hsla("+(i*10+150)+",60%,80%,1)";
    ctx.fillStyle = "hsla("+(i*10+150)+",60%,80%,0.7)";


// this is all the other stuff to make it work
const audioApi = new window.AudioContext;

// variables
var audioBuffer,
    frequencyData = new Uint8Array(4096);

// create an audio API analyser node and connect to source
function createAnalyserNode(audioSource) {
  analyserNode = audioApi.createAnalyser();
  analyserNode.fftSize = 8192;

// getUserMedia success callback -> pipe audio stream into audio API
function gotStream(stream) {
    // Create an audio input from the stream.
    console.log('got stream');
    var audioSource = audioApi.createMediaStreamSource(stream);

function adjustFreqData(shapeNo) {
  var removed = frequencyData.slice(0,1024);
  var newFreqs = [], lowFreqs, midFreqs, highFreqs, prevRangeStart = 0, prevItemCount = 0;

  // set up the maxPow & thus ratio based on shapeCount
  var maxPow = Math.pow(2,shapeNo/2);
  var ratio = 1024/maxPow;
  // looping - get values for new array based on shapeCount
  for (let j=1; j<shapeNo+1; j++) {
    var itemCount, rangeStart;

    var pow = j/2;

    // use ratio to get itemCount (round)
    itemCount = Math.ceil( ((Math.pow(2, pow))*ratio)/2 );

    rangeStart = prevRangeStart + Math.ceil(prevItemCount/2);
     // get new values
    var newValue = 0, total = 0;
    for (let k=rangeStart; k<rangeStart+itemCount; k++) {
      // add up items and divide by total
      total += frequencyData[k];
      newValue = parseInt(total/itemCount);
    // add to new array

    prevItemCount = itemCount;
    prevRangeStart = rangeStart;

  var oneThird = Math.floor(shapeNo/3);

  function avFreqs(arrPart) {
    var arrPart = arrPart;
    var avValue;
    var totalVal = 0;
    for (let l=0; l<arrPart.length; l++) {
      totalVal += arrPart[l];
    avValue = Math.floor(totalVal/arrPart.length);
    return avValue;

  lowFreqs = avFreqs(newFreqs.slice(0,oneThird));
  midFreqs = avFreqs(newFreqs.slice(oneThird, oneThird*2));
  highFreqs = avFreqs(newFreqs.slice(oneThird*2));
  return {
    newFreqs: newFreqs,
    lowFreqs: lowFreqs,
    midFreqs: midFreqs,
    highFreqs: highFreqs

// pipe in analysing to getUserMedia
navigator.mediaDevices.getUserMedia({ audio: true, video: false })

function draw() {

const screen = {
  width: window.innerWidth,
  height: window.innerHeight,
  centerX: window.innerWidth/2,
  centerY: window.innerHeight/2,
  maxRadius: (window.innerHeight-(window.innerHeight/6))/2,
  minRadius: (window.innerHeight/10)/2
// Converts from degrees to radians.
Math.radians = function(degrees) {
  return degrees * Math.PI / 180;

function drawHex(ctx, sideLength, startX, startY) {

  // maths mother fucker
  const moveX = Math.sin(Math.radians(30))*sideLength;
  const moveY = Math.cos(Math.radians(30))*sideLength;

  // I actually want the origin to be in the centre
  var startX = startX-(sideLength/2);
  var startY = startY-moveY;

  ctx.beginPath(); // instigate
  ctx.moveTo(startX, startY); // start at pos
  ctx.lineTo(startX+sideLength, startY); // go right along top (we're drawing clockwise from top left)

  ctx.lineTo(startX+sideLength+moveX, startY+moveY);
  ctx.lineTo(startX+sideLength, startY+(moveY*2));
  ctx.lineTo(startX, startY+(moveY*2));
  ctx.lineTo(startX-moveX, startY+moveY);
  ctx.lineTo(startX, startY);

 var canvas = document.querySelector('canvas');
    canvas.width = screen.width;
    canvas.height = screen.height;
  var ctx = canvas.getContext('2d');