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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.

HTML

            
              <canvas id='canvas'></canvas>

<!--

    Click to clear the canvas

-->
            
          
!

CSS

            
              body { 
  margin:0px;
  overflow: hidden;
background: rgb(255,255,255);
background: -moz-radial-gradient(center, ellipse cover,  rgba(255,255,255,1) 0%, rgba(171,209,234,1) 100%);
background: -webkit-gradient(radial, center center, 0px, center center, 100%, color-stop(0%,rgba(255,255,255,1)), color-stop(100%,rgba(171,209,234,1)));
background: -webkit-radial-gradient(center, ellipse cover,  rgba(255,255,255,1) 0%,rgba(171,209,234,1) 100%);
background: -o-radial-gradient(center, ellipse cover,  rgba(255,255,255,1) 0%,rgba(171,209,234,1) 100%);
background: -ms-radial-gradient(center, ellipse cover,  rgba(255,255,255,1) 0%,rgba(171,209,234,1) 100%);
background: radial-gradient(ellipse at center,  rgba(255,255,255,1) 0%,rgba(171,209,234,1) 100%);
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#ffffff', endColorstr='#abd1ea',GradientType=1 );





}
            
          
!

JS

            
              // Draw Worm
// Ported from flash demo - http://wonderfl.net/c/9os2
//
function DrawWorm(){
  
  var canvas;
  var context;

  var width;
  var height;
	
	var mouse = {x: window.innerWidth/2, y: window.innerHeight};
  this.mouse = mouse;
		
	var interval;
	
	var vms = [];
	
	var MAX_NUM = 100;
	var N = 80;
	
	var px = window.innerWidth/2;
	var py = window.innerHeight;
		
	this.initialize = function(){
		canvas  = document.getElementById("canvas");
		context = canvas.getContext('2d');
			
		width = window.innerWidth;
		height = window.innerHeight;
		
		canvas.width = width;
		canvas.height = height;
		
		canvas.addEventListener('touchmove', TouchMove, false);
		canvas.addEventListener('mousemove', MouseMove, false);
		canvas.addEventListener('click', MouseDown, false);
		
		//Set interval - Bad! - I know!
		var interval = setInterval(Draw, 20);
		
	}
	
	var Draw = function(){
		
		var len = vms.length;
		var i;
		
		//fadeScreen();
		
		for (i = 0; i < len; i++){
			
			var o = vms[i];
			
			if (o.count < N){
				DrawWorm(o);
				o.count++;				
			//This looks a tad hacky - modifying the loop from within :S
			} else {
				len--;
				vms.splice(i, 1);
				i--;
			}	
		}
		
		Check();
	}
	
	//Takes a worm (obj) param
	var DrawWorm = function (obj){

		if (Math.random() > 0.9){
			obj.tmt.rotate(-obj.r * 2);
			obj.r *= -1;
		}
		
		//Prepend is just concat -- right?

		obj.vmt.prependMatrix(obj.tmt);
			
		var cc1x = -obj.w * obj.vmt.c + obj.vmt.tx;
		var cc1y = -obj.w * obj.vmt.d + obj.vmt.ty;
		
		var pp1x = (obj.c1x + cc1x) / 2;
		var pp1y = (obj.c1y + cc1y) / 2;
		
		var cc2x = obj.w * obj.vmt.c + obj.vmt.tx;
		var cc2y = obj.w * obj.vmt.d + obj.vmt.ty;
		
		var pp2x = (obj.c2x + cc2x) / 2;
		var pp2y = (obj.c2y + cc2y) / 2;
		
		context.fillStyle = '#000000';
		context.strokeStyle = '#000000';
		context.beginPath();

		context.moveTo(obj.p1x , obj.p1y);
		context.quadraticCurveTo(obj.c1x, obj.c1y, pp1x, pp1y);
		
   		context.lineTo(pp2x, pp2y);
   		
   		context.quadraticCurveTo(obj.c2x, obj.c2y, obj.p2x, obj.p2y);
   		
   		//context.stroke();
		context.closePath();
		context.fill();	
		
	
	    obj.c1x = cc1x;
        obj.c1y = cc1y;
        obj.p1x = pp1x;
        obj.p1y = pp1y;
        obj.c2x = cc2x;
        obj.c2y = cc2y;
        obj.p2x = pp2x;
        obj.p2y = pp2y;
	}
	
	var Check = function(){
		
		var x0 = mouse.x;
		var y0 = mouse.y;
		
		var vx = x0 - px;
		var vy = y0 - py;	
		
		var len = Math.min(Magnitude(vx, vy), 50);
		
		if (len < 10){
			return;
		}
		
		var matrix = new Matrix2D();		
	
		matrix.rotate((Math.atan2(vy, vx)));
		
		matrix.translate(x0, y0);
			
		createWorm(matrix, len);
		
		context.beginPath(); 
		context.strokeStyle = '#000000';
   		context.moveTo(px, py);
   		context.lineTo(x0, y0);
   		context.stroke();
   		context.closePath();
   		
   		px = x0;
   		py = y0;
   	
		//More logic here for afterwards?
	}
	
	var createWorm = function(mtx, len){
				
		var angle = Math.random() * (Math.PI/6 - Math.PI/64) + Math.PI/64;
		
		if(Math.random() > 0.5){
			angle *= -1;		
		}
		

		var tmt = new Matrix2D();	
		tmt.scale(0.95, 0.95);
		tmt.rotate(angle);			
		tmt.translate(len, 0);
		
		var w = 0.5;

		 var obj = new Worm();
 		
		 obj.c1x = (-w * mtx.c + mtx.tx);
		 obj.p1x = (-w * mtx.c + mtx.tx);
		 	
		 obj.c1y = (-w * mtx.d + mtx.ty);
		 obj.p1y = (-w * mtx.d + mtx.ty);	
		 	
		 obj.c2x = (w * mtx.c + mtx.tx);
		 obj.p2x = (w * mtx.c + mtx.tx);	
		 	 
		 obj.c2y = (w * mtx.d + mtx.ty);
		 obj.p2y = (w * mtx.d + mtx.ty); 
	 	 
		 obj.vmt = mtx;
		 obj.tmt = tmt;
 		
		 obj.r = angle;
		 obj.w = len/20;
		 obj.count = 0;
 		
		 vms.push(obj);
		
		if (vms.length > MAX_NUM){
			vms.shift();
		}
	}
	
	//Not sure why they do this kinda thing in flash.
	var Worm = function(){	
		this.c1x = null;
		this.c1y = null;
		this.c2x = null;
		this.c2y = null;
		this.p1x = null;
		this.p1y = null;
		this.p2x = null;
		this.p2y = null;
		
		this.w = null;
		this.r = null;
		
		this.count = null;
		this.vmt = null;
		this.tmt = null;
		
	}
	
	var fadeScreen = function(){
		context.fillStyle = 'rgba(255, 255, 255, 0.02)';
		context.beginPath();
		context.rect(0, 0, width, height);
		context.closePath();
		context.fill();	
	}
	
	//Clear the screen, 
	var MouseDown = function(e) {
		e.preventDefault();
		canvas.width = canvas.width;
		vms = [];
	}
	
	var MouseMove = function(e) {
        mouse.x = e.layerX - canvas.offsetLeft;
        mouse.y = e.layerY - canvas.offsetTop;
	}
	
	var TouchMove = function(e) {
		e.preventDefault();
    	mouse.x = e.targetTouches[0].pageX - canvas.offsetLeft;
    	mouse.y = e.targetTouches[0].pageY - canvas.offsetTop;
	}
	
	//Returns Magnitude
	var Magnitude = function(x, y){
		return Math.sqrt((x * x) + (y * y));
	}
			
}
    
//Hacked up matrix, borrowed from easel.js -- thanks grant!
//
// -- If you are forking this, then you will want to play with the code above this line.
// -- Unless you are totally nuts!
//
(function(window) {


var Matrix2D = function(a, b, c, d, tx, ty) {
  this.initialize(a, b, c, d, tx, ty);
}
var p = Matrix2D.prototype;

// static public properties:

	Matrix2D.identity = null; // set at bottom of class definition.

	Matrix2D.DEG_TO_RAD = Math.PI/180;


	p.a = 1;

	p.b = 0;

	p.c = 0;

	p.d = 1;

	p.tx = 0;

	p.ty = 0;

	p.alpha = 1;

	p.shadow  = null;

	p.compositeOperation  = null;

	p.initialize = function(a, b, c, d, tx, ty) {
		if (a != null) { this.a = a; }
		this.b = b || 0;
		this.c = c || 0;
		if (d != null) { this.d = d; }
		this.tx = tx || 0;
		this.ty = ty || 0;
	}

	p.prepend = function(a, b, c, d, tx, ty) {
		var n11 = a * this.a + b * this.c;
		var n12 = a * this.b + b * this.d;
		var n21 = c * this.a + d * this.c; 
		var n22 = c * this.b + d * this.d;
		var n31 = tx * this.a + ty * this.c + this.tx; 
		var n32 = tx * this.b + ty * this.d + this.ty;
			
		this.a  = n11;
		this.b  = n12;
		this.c  = n21;
		this.d  = n22;
		this.tx = n31;
		this.ty = n32;
	}

	p.append = function(a, b, c, d, tx, ty) {
		var a1 = this.a;
		var b1 = this.b;
		var c1 = this.c;
		var d1 = this.d;

		this.a  = a*a1+b*c1;
		this.b  = a*b1+b*d1;
		this.c  = c*a1+d*c1;
		this.d  = c*b1+d*d1;
		this.tx = tx*a1+ty*c1+this.tx;
		this.ty = tx*b1+ty*d1+this.ty;
		
	}

	p.prependMatrix = function(matrix) {
		this.prepend(matrix.a, matrix.b, matrix.c, matrix.d, matrix.tx, matrix.ty);
		this.prependProperties(matrix.alpha, matrix.shadow,  matrix.compositeOperation);
	}

	p.appendMatrix = function(matrix) {
		this.append(matrix.a, matrix.b, matrix.c, matrix.d, matrix.tx, matrix.ty);
		this.appendProperties(matrix.alpha, matrix.shadow,  matrix.compositeOperation);
	}

	p.prependTransform = function(x, y, scaleX, scaleY, rotation, skewX, skewY, regX, regY) {
		if (rotation%360) {
			var r = rotation*Matrix2D.DEG_TO_RAD;
			var cos = Math.cos(r);
			var sin = Math.sin(r);
		} else {
			cos = 1;
			sin = 0;
		}

		if (regX || regY) {
			// append the registration offset:
			this.tx -= regX; this.ty -= regY;
		}
		if (skewX || skewY) {
			// TODO: can this be combined into a single prepend operation?
			skewX *= Matrix2D.DEG_TO_RAD;
			skewY *= Matrix2D.DEG_TO_RAD;
			this.prepend(cos*scaleX, sin*scaleX, -sin*scaleY, cos*scaleY, 0, 0);
			this.prepend(Math.cos(skewY), Math.sin(skewY), -Math.sin(skewX), Math.cos(skewX), x, y);
		} else {
			this.prepend(cos*scaleX, sin*scaleX, -sin*scaleY, cos*scaleY, x, y);
		}

	}

	p.appendTransform = function(x, y, scaleX, scaleY, rotation, skewX, skewY, regX, regY) {
		if (rotation%360 == 0 && scaleX == 1 && scaleY == 1 && skewX == 0 && skewY == 0) {
			this.tx += x-regX;
			this.ty += y-regY;
			return;
		}

		if (rotation%360) {
			var r = rotation*Matrix2D.DEG_TO_RAD;
			var cos = Math.cos(r);
			var sin = Math.sin(r);
		} else {
			cos = 1;
			sin = 0;
		}

		if (skewX || skewY) {
			// TODO: can this be combined into a single append?
			skewX *= Matrix2D.DEG_TO_RAD;
			skewY *= Matrix2D.DEG_TO_RAD;
			this.append(Math.cos(skewY), Math.sin(skewY), -Math.sin(skewX), Math.cos(skewX), x, y);
			this.append(cos*scaleX, sin*scaleX, -sin*scaleY, cos*scaleY, 0, 0);
		} else {
			this.append(cos*scaleX, sin*scaleX, -sin*scaleY, cos*scaleY, x, y);
		}

		if (regX || regY) {
			// prepend the registration offset:
			this.tx -= regX*this.a+regY*this.c;
			this.ty -= regX*this.b+regY*this.d;
		}
	}

	p.rotate = function(angle) {
		 var sin = Math.sin(angle);
         var cos = Math.cos(angle);
         var n11 = cos * this.a + sin * this.c;
         var n12 = cos * this.b + sin * this.d;
         var n21 = -sin * this.a + cos * this.c;
         var n22 = -sin * this.b + cos * this.d;
	     this.a  = n11; 
	     this.b  = n12;
         this.c  = n21;
         this.d  = n22;
	}

	p.skew = function(skewX, skewY) {
		skewX = skewX*Matrix2D.DEG_TO_RAD;
		skewY = skewY*Matrix2D.DEG_TO_RAD;
		this.append(Math.cos(skewY), Math.sin(skewY), -Math.sin(skewX), Math.cos(skewX), 0, 0);
	}

	p.scale = function(x, y) {
		this.a *= x;
		this.d *= y;
		this.tx *= x;
		this.ty *= y;
	}

	p.translate = function(x, y) {
		this.tx += x;
		this.ty += y;
	}

	p.identity = function() {
		this.alpha = this.a = this.d = 1;
		this.b = this.c = this.tx = this.ty = 0;
		this.shadow = this.compositeOperation = null;
	}

	p.invert = function() {
		var a1 = this.a;
		var b1 = this.b;
		var c1 = this.c;
		var d1 = this.d;
		var tx1 = this.tx;
		var n = a1*d1-b1*c1;

		this.a = d1/n;
		this.b = -b1/n;
		this.c = -c1/n;
		this.d = a1/n;
		this.tx = (c1*this.ty-d1*tx1)/n;
		this.ty = -(a1*this.ty-b1*tx1)/n;
	}

	p.isIdentity = function() {
		return this.tx == 0 && this.ty == 0 && this.a == 1 && this.b == 0 && this.c == 0 && this.d == 1;
	}

	p.decompose = function(target) {
		// TODO: it would be nice to be able to solve for whether the matrix can be decomposed into only scale/rotation
		// even when scale is negative
		if (target == null) { target = {}; }
		target.x = this.tx;
		target.y = this.ty;
		target.scaleX = Math.sqrt(this.a * this.a + this.b * this.b);
		target.scaleY = Math.sqrt(this.c * this.c + this.d * this.d);

		var skewX = Math.atan2(-this.c, this.d);
		var skewY = Math.atan2(this.b, this.a);

		if (skewX == skewY) {
			target.rotation = skewY/Matrix2D.DEG_TO_RAD;
			if (this.a < 0 && this.d >= 0) {
				target.rotation += (target.rotation <= 0) ? 180 : -180;
			}
			target.skewX = target.skewY = 0;
		} else {
			target.skewX = skewX/Matrix2D.DEG_TO_RAD;
			target.skewY = skewY/Matrix2D.DEG_TO_RAD;
		}
		return target;
	}

	p.reinitialize = function(a,b,c,d,tx,ty,alpha,shadow,compositeOperation) {
		this.initialize(a,b,c,d,tx,ty);
		this.alpha = alpha || 1;
		this.shadow = shadow;
		this.compositeOperation = compositeOperation;
		return this;
	}

	p.appendProperties = function(alpha, shadow, compositeOperation) {
		this.alpha *= alpha;
		this.shadow = shadow || this.shadow;
		this.compositeOperation = compositeOperation || this.compositeOperation;
	}

	p.prependProperties = function(alpha, shadow, compositeOperation) {
		this.alpha *= alpha;
		this.shadow = this.shadow || shadow;
		this.compositeOperation = this.compositeOperation || compositeOperation;
	}

	p.clone = function() {
		var mtx = new Matrix2D(this.a, this.b, this.c, this.d, this.tx, this.ty);
		mtx.shadow = this.shadow;
		mtx.alpha = this.alpha;
		mtx.compositeOperation = this.compositeOperation;
		return mtx;
	}


	p.toString = function() {
		return "[Matrix2D (a="+this.a+" b="+this.b+" c="+this.c+" d="+this.d+" tx="+this.tx+" ty="+this.ty+")]";
	}

	// this has to be populated after the class is defined:
	Matrix2D.identity = new Matrix2D(1, 0, 0, 1, 0, 0);

window.Matrix2D = Matrix2D;
}(window));    

var app, interval, count;

function demoApp() {
  count++;
  if (count % 2 == 0){
	  app.mouse.y -= 40    
      } else {
       app.mouse.y += 40; 
      }

  if (count > 30) {
   window.clearInterval( interval );
  }
}

setTimeout( function() {
  app = new DrawWorm();
  app.initialize();
  count = 0;
  interval = setInterval( demoApp, 20 );
}, 10);
            
          
!
999px

Console