https://www.knights-magic.com/assets/common/js/jquery.mousewheel.js

1/*! Copyright (c) 2013 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: 3.1.3
9 *
10 * Requires: 1.2.2+
11 */
12
13(function (factory) {
14    if ( typeof define === 'function' && define.amd ) {
15        // AMD. Register as an anonymous module.
16        define(['jquery'], factory);
17    } else if (typeof exports === 'object') {
18        // Node/CommonJS style for Browserify
19        module.exports = factory;
20    } else {
21        // Browser globals
22        factory(jQuery);
23    }
24}(function ($) {
25
26    var toFix = ['wheel', 'mousewheel', 'DOMMouseScroll', 'MozMousePixelScroll'];
27    var toBind = 'onwheel' in document || document.documentMode >= 9 ? ['wheel'] : ['mousewheel', 'DomMouseScroll', 'MozMousePixelScroll'];
28    var lowestDelta, lowestDeltaXY;
29
30    if ( $.event.fixHooks ) {
31        for ( var i = toFix.length; i; ) {
32            $.event.fixHooks[ toFix[--i] ] = $.event.mouseHooks;
33        }
34    }
35
36    $.event.special.mousewheel = {
37        setup: function() {
38            if ( this.addEventListener ) {
39                for ( var i = toBind.length; i; ) {
40                    this.addEventListener( toBind[--i], handler, false );
41                }
42            } else {
43                this.onmousewheel = handler;
44            }
45        },
46
47        teardown: function() {
48            if ( this.removeEventListener ) {
49                for ( var i = toBind.length; i; ) {
50                    this.removeEventListener( toBind[--i], handler, false );
51                }
52            } else {
53                this.onmousewheel = null;
54            }
55        }
56    };
57
58    $.fn.extend({
59        mousewheel: function(fn) {
60            return fn ? this.bind("mousewheel", fn) : this.trigger("mousewheel");
61        },
62
63        unmousewheel: function(fn) {
64            return this.unbind("mousewheel", fn);
65        }
66    });
67
68
69    function handler(event) {
70        var orgEvent = event || window.event,
71            args = [].slice.call(arguments, 1),
72            delta = 0,
73            deltaX = 0,
74            deltaY = 0,
75            absDelta = 0,
76            absDeltaXY = 0,
77            fn;
78        event = $.event.fix(orgEvent);
79        event.type = "mousewheel";
80
81        // Old school scrollwheel delta
82        if ( orgEvent.wheelDelta ) { delta = orgEvent.wheelDelta; }
83        if ( orgEvent.detail )     { delta = orgEvent.detail * -1; }
84
85        // New school wheel delta (wheel event)
86        if ( orgEvent.deltaY ) {
87            deltaY = orgEvent.deltaY * -1;
88            delta  = deltaY;
89        }
90        if ( orgEvent.deltaX ) {
91            deltaX = orgEvent.deltaX;
92            delta  = deltaX * -1;
93        }
94
95        // Webkit
96        if ( orgEvent.wheelDeltaY !== undefined ) { deltaY = orgEvent.wheelDeltaY; }
97        if ( orgEvent.wheelDeltaX !== undefined ) { deltaX = orgEvent.wheelDeltaX * -1; }
98
99        // Look for lowest delta to normalize the delta values
100        absDelta = Math.abs(delta);
101        if ( !lowestDelta || absDelta < lowestDelta ) { lowestDelta = absDelta; }
102        absDeltaXY = Math.max(Math.abs(deltaY), Math.abs(deltaX));
103        if ( !lowestDeltaXY || absDeltaXY < lowestDeltaXY ) { lowestDeltaXY = absDeltaXY; }
104
105        // Get a whole value for the deltas
106        fn = delta > 0 ? 'floor' : 'ceil';
107        delta  = Math[fn](delta / lowestDelta);
108        deltaX = Math[fn](deltaX / lowestDeltaXY);
109        deltaY = Math[fn](deltaY / lowestDeltaXY);
110
111        // Add event and delta to the front of the arguments
112        args.unshift(event, delta, deltaX, deltaY);
113
114        return ($.event.dispatch || $.event.handle).apply(this, args);
115    }
116
117}));