jquery-ui/ui/jquery.effects.bounce.js

/*!
 * jQuery UI Effects Bounce @VERSION
 *
 * Copyright 2012, AUTHORS.txt (http://jqueryui.com/about)
 * Dual licensed under the MIT or GPL Version 2 licenses.
 * http://jquery.org/license
 *
 * http://docs.jquery.com/UI/Effects/Bounce
 *
 * Depends:
 *	jquery.effects.core.js
 */
(function( $, undefined ) {

$.effects.effect.bounce = function( o, done ) {
	var el = $( this ), 
		props = [ "position", "top", "bottom", "left", "right", "height", "width" ],

		// defaults:
		mode = $.effects.setMode( el, o.mode || "effect" ),
		hide = mode === "hide",
		show = mode === "show",
		direction = o.direction || "up", 
		distance = o.distance,
		times = o.times || 5,

		// number of internal animations
		anims = times * 2 + ( show || hide ? 1 : 0 ),
		speed = o.duration / anims,
		easing = o.easing,

		// utility:
		ref = ( direction === "up" || direction === "down" ) ? "top" : "left",
		motion = ( direction === "up" || direction === "left" ), 
		i,
		upAnim,
		downAnim,

		// we will need to re-assemble the queue to stack our animations in place
		queue = el.queue(),
		queuelen = queue.length;

	// Avoid touching opacity to prevent clearType and PNG issues in IE	
	if ( show || hide ) {
		props.push( "opacity" );
	} 

	$.effects.save( el, props ); 
	el.show(); 
	$.effects.createWrapper( el ); // Create Wrapper

	// default distance for the BIGGEST bounce is the outer Distance / 3
	if ( !distance ) {
		distance = el[ ref === "top" ? "outerHeight" : "outerWidth" ]() / 3;
	}

	if ( show ) {
		downAnim = { opacity: 1 };
		downAnim[ ref ] = 0;

		// if we are showing, force opacity 0 and set the initial position
		// then do the "first" animation
		el.css( "opacity", 0 )
			.css( ref, motion ? -distance * 2 : distance * 2 )
			.animate( downAnim, speed, easing );
	}

	// start at the smallest distance if we are hiding
	if ( hide ) {
		distance = distance / Math.pow( 2, times - 1 );
	}

	downAnim = {};
	downAnim[ ref ] = 0;
	// Bounces up/down/left/right then back to 0 -- times * 2 animations happen here
	for ( i = 0; i < times; i++ ) {
		upAnim = {};
		upAnim[ ref ] = ( motion ? "-=" : "+=" ) + distance;

		el.animate( upAnim, speed, easing )
			.animate( downAnim, speed, easing );

		distance = hide ? distance * 2 : distance / 2;
	}

	// Last Bounce when Hiding
	if ( hide ) {
		upAnim = { opacity: 0 };
		upAnim[ ref ] = ( motion ? "-=" : "+=" ) + distance;

		el.animate( upAnim, speed, easing );
	}
	
	el.queue(function() {
		if ( hide ) {
			el.hide();
		}
		$.effects.restore( el, props );
		$.effects.removeWrapper( el );
		done();
	});

	// inject all the animations we just queued to be first in line (after "inprogress")
	if ( queuelen > 1) {
		queue.splice.apply( queue,
			[ 1, 0 ].concat( queue.splice( queuelen, anims + 1 ) ) );
	}
	el.dequeue();

};

})(jQuery);