ish.js API Doc (alpha)

// Refactored from; http://www.schillmania.com/content/projects/javascript-animation-3/

/**
 * Not included in any default dist, compile your own if you wish to use. Easing equations mainly used in animation to calculate tween frame values. Each method shares the same parameters and return value as below.
 * <div class="c-returns"><h5 class="c-returns__header">Returns</h5><code>Number</code><p>The tween value for the currentFrame.</p></div><h5>Parameters:</h5>
<table class="c-params">
<thead>
<tr>
<th>Name</th>
<th>Type</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td class="name">currentFrame</td>
<td class="type">
<code>Number</code>
</td>
<td class="description last"><p>The current frame</p></td>
</tr>
<tr>
<td class="name">startValue</td>
<td class="type">
<code>Number</code>
</td>
<td class="description last"><p>The start value of the number to be tweened</p></td>
</tr>
<tr>
<td class="name">valueChange</td>
<td class="type">
<code>Number</code>
</td>
<td class="description last"><p>The total ammount of change the tweened value will expierience over the length of its animation. For example if you're tween from 100 to 200 the <code>valueChange</code> would be 100.</p></td>
</tr>
<tr>
<td class="name">totalFrames</td>
<td class="type">
<code>Number</code>
</td>
<td class="description last"><p>The total number of tween frames.</p></td>
</tr>
</tbody>
</table>
 * 
 * @name  ish.fn.easing
 * @namespace
 *
 */
$.fn.easing = {
	/**
	 * @memberOf ish.fn.easing
	 */
	linear: function(currentFrame, startValue, valueChange, totalFrames) {
		return valueChange * currentFrame / totalFrames + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInQuad: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return valueChange * currentFrame * currentFrame + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutQuad: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return -valueChange * currentFrame * (currentFrame - 2) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutQuad: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return valueChange / 2 * currentFrame * currentFrame + startValue;
		currentFrame--;
		return -valueChange / 2 * (currentFrame * (currentFrame - 2) - 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 * 
	 */
	easeInCubic: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return valueChange * currentFrame * currentFrame * currentFrame + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutCubic: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		currentFrame--;
		return valueChange * (currentFrame * currentFrame * currentFrame + 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutCubic: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return valueChange / 2 * currentFrame * currentFrame * currentFrame + startValue;
		currentFrame -= 2;
		return valueChange / 2 * (currentFrame * currentFrame * currentFrame + 2) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInQuart: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return valueChange * currentFrame * currentFrame * currentFrame * currentFrame + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutQuart: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		currentFrame--;
		return -valueChange * (currentFrame * currentFrame * currentFrame * currentFrame - 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutQuart: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return valueChange / 2 * currentFrame * currentFrame * currentFrame * currentFrame + startValue;
		currentFrame -= 2;
		return -valueChange / 2 * (currentFrame * currentFrame * currentFrame * currentFrame - 2) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInQuint: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return valueChange * currentFrame * currentFrame * currentFrame * currentFrame * currentFrame + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutQuint: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		currentFrame--;
		return valueChange * (currentFrame * currentFrame * currentFrame * currentFrame * currentFrame + 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutQuint: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return valueChange / 2 * currentFrame * currentFrame * currentFrame * currentFrame * currentFrame + startValue;
		currentFrame -= 2;
		return valueChange / 2 * (currentFrame * currentFrame * currentFrame * currentFrame * currentFrame + 2) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInSine: function(currentFrame, startValue, valueChange, totalFrames) {
		return -valueChange * Math.cos(currentFrame / totalFrames * (Math.PI / 2)) + valueChange + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutSine: function(currentFrame, startValue, valueChange, totalFrames) {
		return valueChange * Math.sin(currentFrame / totalFrames * (Math.PI / 2)) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutSine: function(currentFrame, startValue, valueChange, totalFrames) {
		return -valueChange / 2 * (Math.cos(Math.PI * currentFrame / totalFrames) - 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInExpo: function(currentFrame, startValue, valueChange, totalFrames) {
		return valueChange *
			Math.pow(2, 10 * (currentFrame / totalFrames - 1)) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutExpo: function(currentFrame, startValue, valueChange, totalFrames) {
		return valueChange * (-
			Math.pow(2, -10 * currentFrame / totalFrames) + 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutExpo: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return valueChange / 2 *
			Math.pow(2, 10 * (currentFrame - 1)) + startValue;
		currentFrame--;
		return valueChange / 2 * (-
			Math.pow(2, -10 * currentFrame) + 2) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInCirc: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		return -valueChange * (Math.sqrt(1 - currentFrame * currentFrame) - 1) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeOutCirc: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames;
		currentFrame--;
		return valueChange *
			Math.sqrt(1 - currentFrame * currentFrame) + startValue;
	},
	/**
	 * @memberOf ish.fn.easing
	 */
	easeInOutCirc: function(currentFrame, startValue, valueChange, totalFrames) {
		currentFrame /= totalFrames / 2;
		if (currentFrame < 1) return -valueChange / 2 * (Math.sqrt(1 - currentFrame * currentFrame) - 1) + startValue;
		currentFrame -= 2;
		return valueChange / 2 * (Math.sqrt(1 - currentFrame * currentFrame) + 1) + startValue;
	}
};