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

/*
 * jQuery UI Effects Bounce @VERSION
 *
 * Copyright 2011, 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) {

	return this.queue( function( next ) {
		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( next ) {
			if ( hide ) {
				el.hide();
			}
			$.effects.restore( el, props );
			$.effects.removeWrapper( el );
			if ( o.complete ) {
				o.complete.apply( el[ 0 ] );
			}
			next();
		});

		// 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 ) ) );
		}
		next();

	});

};

})(jQuery);