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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <p>This may take a while to render. Be patient!</p>
<div id="paper"></div>
              #paper, p{
  width: 400px;
  margin: 50px auto 0;

p {
  margin: 0 auto;
  font-family: Helvetica, Arial, Verdana, sans-serif;
  font-size: .7em;
  text-align: center;
                var paper = Raphael("paper", 400, 400);
  //the shape to hold all others
  var master =, paper.width/2, 200);

master.attr({stroke: "#eee"});

  var colours = ['#00f;']; // will be filled from the api 
  var iterations = 100; //How many times to try before shrinking the circle
  var r = 50; //30
  var shrink = 0.6; //.6
  var padding = 2;
  var min_r = 4; //4
  var fail = 0; //number of times this size circle has failed placement

/* Get a random palette from via their API */
$(function () {
    function (result) {
      colours = result[0].colors;
      do {
        fail = 0; // reset failure count
        r = Math.floor(r*shrink);
        iterations = iterations*3; // increase the number of attempts each shrink. should result in more smaller dots
        console.log("still iterating. r now = ", r);
      } while (r > min_r);

  /* check for overlap by checking the distance between the two centers, then comparing to the two radii plus padding. */
  function areColliding(existing,test){  
    if ( ==={
      return false;
    } else {
      return Math.sqrt((Math.pow(,2) + Math.pow( -,2))) < existing.attrs.r+test.attrs.r+padding;

/* check for overlap by checking the distance between the two centers, then comparing against the two radii. */
  function insideMaster(c){
    return (Math.sqrt((Math.pow(,2)+Math.pow(,2)))<(master.attrs.r-c.attrs.r));

  function removeFailure(circle){
  function drawCircles() {
    do {
      var circle =*(2*master.attrs.r), Math.floor(Math.random()*(2*master.attrs.r), r);
      var thisid =;
      //Is it inside the master shape?
      if (!insideMaster(circle)){
      //loop through all other circles and check for overlap
      paper.forEach(function (el) {
          if ( !== thisid && circle.node !== null){
            if (areColliding(circle, el)){
      //colour in the winner!
      circle.attr({fill: "#"+colours[fail % colours.length], stroke: false});
    } while (fail < iterations);

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