examples/12_graphs_custom_functions.html

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		<title>Tween.js / graphs for custom easing functions</title>
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			body {
				margin: 0px;
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			#target {
				font-size: 13px;
				padding: 0px 32px;
			}

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			<h1><a href="http://github.com/tweenjs/tween.js">tween.js</a></h1>
			<h2>12 _ graphs for custom easing functions</h2>
			<p>A version of the <a href="03_graphs.html">graphs</a> example, but using custom easing functions (not included in <a href="https://github.com/tween.js/tween.js">tween.js</a> by default).</p>
		</div>

		<div id="target"></div>

		<script src="../src/Tween.js"></script>
		<script src="js/RequestAnimationFrame.js"></script>
		<script src="js/createGraph.js"></script>
		<script>

			window.addEventListener('load', function() {
				init();
				animate();
			});

			function init() {

				var target = document.getElementById('target');

				target.appendChild( createGraph( 'Ten Steps', tenStepsEasing ) );

				target.appendChild( document.createElement( 'br' ) );
				
				for(var i = 0; i < 4; i++) {
					var numSteps = (i + 1) * 4;
					target.appendChild( createGraph(numSteps + ' steps', createStepFunction(numSteps)) );
				}

				target.appendChild( document.createElement( 'br' ) );

				target.appendChild( createGraph('Random', randomEasing) );

				target.appendChild( document.createElement( 'br' ) );
				
				target.appendChild( createGraph('Noisy Exponential.InOut', createNoisyEasing(0.1, TWEEN.Easing.Exponential.InOut) ) );
				target.appendChild( createGraph('Noisy Elastic.InOut', createNoisyEasing(0.1, TWEEN.Easing.Elastic.InOut) ) );
				target.appendChild( createGraph('Noisy Circular.InOut', createNoisyEasing(0.1, TWEEN.Easing.Circular.InOut) ) );

			}

			function animate() {

				requestAnimationFrame( animate );

				TWEEN.update();

			}

			function tenStepsEasing(k) {
				return (Math.floor(k * 10) / 10);
			}

			// This is where we get very meta and write a function for
			// generating functions! The returned function is similar to 
			// the tenStepsEasing function above, but the number of steps
			// is passed as a parameter
			function createStepFunction(numSteps) {
				return function(k) {
					return (Math.floor(k * numSteps) / numSteps);
				}
			}

			function randomEasing(k) {
				return Math.random();
			}


			// Getting meta again: why not use existing functions as the 
			// base for new easing functions?
			function createNoisyEasing(randomProportion, easingFunction) {
				var normalProportion = 1.0 - randomProportion;
				return function(k) {
					return randomProportion * Math.random() + normalProportion * easingFunction(k);
				}
			}

		</script>
	</body>
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