https://opentutorials.org/static/js/common/jquery.mousewheel.js?4

1/*! Copyright (c) 2011 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: 3.0.6
9 * 
10 * Requires: 1.2.2+
11 */
12
13(function($) {
14
15var types = ['DOMMouseScroll', 'mousewheel'];
16
17if ($.event.fixHooks) {
18    for ( var i=types.length; i; ) {
19        $.event.fixHooks[ types[--i] ] = $.event.mouseHooks;
20    }
21}
22
23$.event.special.mousewheel = {
24    setup: function() {
25        if ( this.addEventListener ) {
26            for ( var i=types.length; i; ) {
27                this.addEventListener( types[--i], handler, false );
28            }
29        } else {
30            this.onmousewheel = handler;
31        }
32    },
33    
34    teardown: function() {
35        if ( this.removeEventListener ) {
36            for ( var i=types.length; i; ) {
37                this.removeEventListener( types[--i], handler, false );
38            }
39        } else {
40            this.onmousewheel = null;
41        }
42    }
43};
44
45$.fn.extend({
46    mousewheel: function(fn) {
47        return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
48    },
49    
50    unmousewheel: function(fn) {
51        return this.unbind("mousewheel", fn);
52    }
53});
54
55
56function handler(event) {
57    var orgEvent = event || window.event, args = [].slice.call( arguments, 1 ), delta = 0, returnValue = true, deltaX = 0, deltaY = 0;
58    event = $.event.fix(orgEvent);
59    event.type = "mousewheel";
60    
61    // Old school scrollwheel delta
62    if ( orgEvent.wheelDelta ) { delta = orgEvent.wheelDelta/120; }
63    if ( orgEvent.detail     ) { delta = -orgEvent.detail/3; }
64    
65    // New school multidimensional scroll (touchpads) deltas
66    deltaY = delta;
67    
68    // Gecko
69    if ( orgEvent.axis !== undefined && orgEvent.axis === orgEvent.HORIZONTAL_AXIS ) {
70        deltaY = 0;
71        deltaX = -1*delta;
72    }
73    
74    // Webkit
75    if ( orgEvent.wheelDeltaY !== undefined ) { deltaY = orgEvent.wheelDeltaY/120; }
76    if ( orgEvent.wheelDeltaX !== undefined ) { deltaX = -1*orgEvent.wheelDeltaX/120; }
77    
78    // Add event and delta to the front of the arguments
79    args.unshift(event, delta, deltaX, deltaY);
80    
81    return ($.event.dispatch || $.event.handle).apply(this, args);
82}
83
84})(jQuery);