text: /**
   * @author mrdoob / http://mrdoob.com/
   * @author jetienne / http://jetienne.com/
   * @author paulirish / http://paulirish.com/
   */
  var MemoryStats = function (){
  
  	var msMin	= 100;
  	var msMax	= 0;
  
  	var container	= document.createElement( 'div' );
  	container.id	= 'stats';
  	container.style.cssText = 'width:80px;opacity:0.9;cursor:pointer';
  
  	var msDiv	= document.createElement( 'div' );
  	msDiv.id	= 'ms';
  	msDiv.style.cssText = 'padding:0 0 3px 3px;text-align:left;background-color:#020;';
  	container.appendChild( msDiv );
  
  	var msText	= document.createElement( 'div' );
  	msText.id	= 'msText';
  	msText.style.cssText = 'color:#0f0;font-family:Helvetica,Arial,sans-serif;font-size:9px;font-weight:bold;line-height:15px';
  	msText.innerHTML= 'Memory';
  	msDiv.appendChild( msText );
  
  	var msGraph	= document.createElement( 'div' );
  	msGraph.id	= 'msGraph';
  	msGraph.style.cssText = 'position:relative;width:74px;height:30px;background-color:#0f0';
  	msDiv.appendChild( msGraph );
  
  	while ( msGraph.children.length < 74 ) {
  
  		var bar = document.createElement( 'span' );
  		bar.style.cssText = 'width:1px;height:30px;float:left;background-color:#131';
  		msGraph.appendChild( bar );
  
  	}
  
  	var updateGraph = function ( dom, height, color ) {
  
  		var child = dom.appendChild( dom.firstChild );
  		child.style.height = height + 'px';
  		if( color ) child.style.backgroundColor = color;
  
  	}
  
  	var perf = window.performance || {};
  	// polyfill usedJSHeapSize
  	if (!perf.memory){
  		perf.memory = { usedJSHeapSize : 0 };
  	}
  
  	// support of the API?
  	if( perf.memory.totalJSHeapSize === 0 ){
  		console.warn('totalJSHeapSize === 0... performance.memory is only available in Chrome .')
  	}
  
  	// TODO, add a sanity check to see if values are bucketed.
  	// If so, remind user to adopt the --enable-precise-memory-info flag.
  	// open -a "/Applications/Google Chrome.app" --args --enable-precise-memory-info
  
  	var lastTime	= Date.now();
  	var lastUsedHeap= perf.memory.usedJSHeapSize;
  	return {
  		domElement: container,
  
  		update: function () {
  
  			// refresh only 30time per second
  			if( Date.now() - lastTime < 1000/30 )	return;
  			lastTime	= Date.now()
  
  			var delta	= perf.memory.usedJSHeapSize - lastUsedHeap;
  			lastUsedHeap	= perf.memory.usedJSHeapSize;
  			var color	= delta < 0 ? '#830' : '#131';
  
  			var ms	= perf.memory.usedJSHeapSize;
  			msMin	= Math.min( msMin, ms );
  			msMax	= Math.max( msMax, ms );
  			msText.textContent = "Mem: " + bytesToSize(ms, 2);
  
  			var normValue	= ms / (30*1024*1024);
  			var height	= Math.min( 30, 30 - normValue * 30 );
  			updateGraph( msGraph, height, color);
  
  			function bytesToSize( bytes, nFractDigit ){
  				var sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB'];
  				if (bytes == 0) return 'n/a';
  				nFractDigit	= nFractDigit !== undefined ? nFractDigit : 0;
  				var precision	= Math.pow(10, nFractDigit);
  				var i 		= Math.floor(Math.log(bytes) / Math.log(1024));
  				return Math.round(bytes*precision / Math.pow(1024, i))/precision + ' ' + sizes[i];
  			};
  		}
  
  	}
  
  };
  