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Add External Stylesheets/Pens

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Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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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.

              <!-- Edit the text with whatever you want :) --> 
<!-- Works with emojis too ! -->
<canvas id="scene"></canvas>
	<input id="copy" type="text" value="Hello Codepen ♥" />
<p>Click anywhere to change the radius of your mouse</p>
			overflow: hidden;
			background: black;
			width: 100vw;
			height: 100vh;
			width: 250px;
			height: 40px;
			line-height: 40px;
			position: absolute;
			bottom: 35px;
			left: calc(50% - 125px);
			background: none;
			color: white;
			font-size: 30px;
			font-family: arial;
			text-align: center;
			border: 1px solid white;
			background: rgba(255,255,255,0.2);
  position: fixed;
  left: 0;
  color: #fff;
  font-family: Helvetica, Verdana, sans-serif;
  width: 100%;
  text-align: center;
  margin: 0;
	var canvas = document.querySelector("#scene"),
		ctx = canvas.getContext("2d"),
		particles = [],
		amount = 0,
		mouse = {x:0,y:0},
		radius = 1;

	var colors = ["#468966","#FFF0A5", "#FFB03B","#B64926", "#8E2800"];

	var copy = document.querySelector("#copy");

	var ww = canvas.width = window.innerWidth;
	var wh = canvas.height = window.innerHeight;

	function Particle(x,y){
		this.x =  Math.random()*ww;
		this.y =  Math.random()*wh;
		this.dest = {
			x : x,
			y: y
		this.r =  Math.random()*5 + 2;
		this.vx = (Math.random()-0.5)*20;
		this.vy = (Math.random()-0.5)*20;
		this.accX = 0;
		this.accY = 0;
		this.friction = Math.random()*0.05 + 0.94;

		this.color = colors[Math.floor(Math.random()*6)];

	Particle.prototype.render = function() {

		this.accX = (this.dest.x - this.x)/1000;
		this.accY = (this.dest.y - this.y)/1000;
		this.vx += this.accX;
		this.vy += this.accY;
		this.vx *= this.friction;
		this.vy *= this.friction;

		this.x += this.vx;
		this.y +=  this.vy;

		ctx.fillStyle = this.color;
		ctx.arc(this.x, this.y, this.r, Math.PI * 2, false);

		var a = this.x - mouse.x;
		var b = this.y - mouse.y;

		var distance = Math.sqrt( a*a + b*b );
			this.accX = (this.x - mouse.x)/100;
			this.accY = (this.y - mouse.y)/100;
			this.vx += this.accX;
			this.vy += this.accY;


	function onMouseMove(e){
		mouse.x = e.clientX;
		mouse.y = e.clientY;

	function onTouchMove(e){
    if(e.touches.length > 0 ){
      mouse.x = e.touches[0].clientX;
      mouse.y = e.touches[0].clientY;

function onTouchEnd(e){
  mouse.x = -9999;
  mouse.y = -9999;

	function initScene(){
		ww = canvas.width = window.innerWidth;
		wh = canvas.height = window.innerHeight;

		ctx.clearRect(0, 0, canvas.width, canvas.height);

		ctx.font = "bold "+(ww/10)+"px sans-serif";
		ctx.textAlign = "center";
		ctx.fillText(copy.value, ww/2, wh/2);

		var data  = ctx.getImageData(0, 0, ww, wh).data;
		ctx.clearRect(0, 0, canvas.width, canvas.height);
		ctx.globalCompositeOperation = "screen";

		particles = [];
		for(var i=0;i<ww;i+=Math.round(ww/150)){
			for(var j=0;j<wh;j+=Math.round(ww/150)){
				if(data[ ((i + j*ww)*4) + 3] > 150){
					particles.push(new Particle(i,j));
		amount = particles.length;


	function onMouseClick(){
		if(radius ===5){
			radius = 0;

	function render(a) {
		ctx.clearRect(0, 0, canvas.width, canvas.height);
		for (var i = 0; i < amount; i++) {

	copy.addEventListener("keyup", initScene);
	window.addEventListener("resize", initScene);
	window.addEventListener("mousemove", onMouseMove);
	window.addEventListener("touchmove", onTouchMove);
	window.addEventListener("click", onMouseClick);
	window.addEventListener("touchend", onTouchEnd);

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