1/*! Copyright (c) 2010 Brandon Aaron (http://brandonaaron.net)
2 * Licensed under the MIT License (LICENSE.txt).
3 *
4 * Thanks to: http://adomas.org/javascript-mouse-wheel/ for some pointers.
5 * Thanks to: Mathias Bank(http://www.mathias-bank.de) for a scope bug fix.
6 * Thanks to: Seamus Leahy for adding deltaX and deltaY
7 *
8 * Version: 3.0.4
9 *
10 * Requires: 1.2.2+
11 */
12
13(function($) {
14
15var types = ['DOMMouseScroll', 'mousewheel'];
16
17$.event.special.mousewheel = {
18    setup: function() {
19        if ( this.addEventListener ) {
20            for ( var i=types.length; i; ) {
21                this.addEventListener( types[--i], handler, false );
22            }
23        } else {
24            this.onmousewheel = handler;
25        }
26    },
27
28    teardown: function() {
29        if ( this.removeEventListener ) {
30            for ( var i=types.length; i; ) {
31                this.removeEventListener( types[--i], handler, false );
32            }
33        } else {
34            this.onmousewheel = null;
35        }
36    }
37};
38
39$.fn.extend({
40    mousewheel: function(fn) {
41        return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
42    },
43
44    unmousewheel: function(fn) {
45        return this.unbind("mousewheel", fn);
46    }
47});
48
49
50function handler(event) {
51    var orgEvent = event || window.event, args = [].slice.call( arguments, 1 ), delta = 0, returnValue = true, deltaX = 0, deltaY = 0;
52    event = $.event.fix(orgEvent);
53    event.type = "mousewheel";
54
55    // Old school scrollwheel delta
56    if ( event.wheelDelta ) { delta = event.wheelDelta/120; }
57    if ( event.detail     ) { delta = -event.detail/3; }
58
59    // New school multidimensional scroll (touchpads) deltas
60    deltaY = delta;
61
62    // Gecko
63    if ( orgEvent.axis !== undefined && orgEvent.axis === orgEvent.HORIZONTAL_AXIS ) {
64        deltaY = 0;
65        deltaX = -1*delta;
66    }
67
68    // Webkit
69    if ( orgEvent.wheelDeltaY !== undefined ) { deltaY = orgEvent.wheelDeltaY/120; }
70    if ( orgEvent.wheelDeltaX !== undefined ) { deltaX = -1*orgEvent.wheelDeltaX/120; }
71
72    // Add event and delta to the front of the arguments
73    args.unshift(event, delta, deltaX, deltaY);
74
75    return $.event.handle.apply(this, args);
76}
77
78})(jQuery);