1 /*! Copyright (c) 2013 Brandon Aaron (http://brandon.aaron.sh) 2 * Licensed under the MIT License (LICENSE.txt). 3 * 4 * Version: 3.1.12 5 * 6 * Requires: jQuery 1.2.2+ 7 */ 8 9 (function (factory) { 10 if ( typeof define === 'function' && define.amd ) { 11 // AMD. Register as an anonymous module. 12 define(['jquery'], factory); 13 } else if (typeof exports === 'object') { 14 // Node/CommonJS style for Browserify 15 module.exports = factory; 16 } else { 17 // Browser globals 18 factory(jQuery); 19 } 20 }(function ($) { 21 22 var toFix = ['wheel', 'mousewheel', 'DOMMouseScroll', 'MozMousePixelScroll'], 23 toBind = ( 'onwheel' in document || document.documentMode >= 9 ) ? 24 ['wheel'] : ['mousewheel', 'DomMouseScroll', 'MozMousePixelScroll'], 25 slice = Array.prototype.slice, 26 nullLowestDeltaTimeout, lowestDelta; 27 28 if ( $.event.fixHooks ) { 29 for ( var i = toFix.length; i; ) { 30 $.event.fixHooks[ toFix[--i] ] = $.event.mouseHooks; 31 } 32 } 33 34 var special = $.event.special.mousewheel = { 35 version: '3.1.12', 36 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 // Store the line height and page height for this particular element 46 $.data(this, 'mousewheel-line-height', special.getLineHeight(this)); 47 $.data(this, 'mousewheel-page-height', special.getPageHeight(this)); 48 }, 49 50 teardown: function() { 51 if ( this.removeEventListener ) { 52 for ( var i = toBind.length; i; ) { 53 this.removeEventListener( toBind[--i], handler, false ); 54 } 55 } else { 56 this.onmousewheel = null; 57 } 58 // Clean up the data we added to the element 59 $.removeData(this, 'mousewheel-line-height'); 60 $.removeData(this, 'mousewheel-page-height'); 61 }, 62 63 getLineHeight: function(elem) { 64 var $elem = $(elem), 65 $parent = $elem['offsetParent' in $.fn ? 'offsetParent' : 'parent'](); 66 if (!$parent.length) { 67 $parent = $('body'); 68 } 69 return parseInt($parent.css('fontSize'), 10) || parseInt($elem.css('fontSize'), 10) || 16; 70 }, 71 72 getPageHeight: function(elem) { 73 return $(elem).height(); 74 }, 75 76 settings: { 77 adjustOldDeltas: true, // see shouldAdjustOldDeltas() below 78 normalizeOffset: true // calls getBoundingClientRect for each event 79 } 80 }; 81 82 $.fn.extend({ 83 mousewheel: function(fn) { 84 return fn ? this.bind('mousewheel', fn) : this.trigger('mousewheel'); 85 }, 86 87 unmousewheel: function(fn) { 88 return this.unbind('mousewheel', fn); 89 } 90 }); 91 92 93 function handler(event) { 94 var orgEvent = event || window.event, 95 args = slice.call(arguments, 1), 96 delta = 0, 97 deltaX = 0, 98 deltaY = 0, 99 absDelta = 0, 100 offsetX = 0, 101 offsetY = 0; 102 event = $.event.fix(orgEvent); 103 event.type = 'mousewheel'; 104 105 // Old school scrollwheel delta 106 if ( 'detail' in orgEvent ) { deltaY = orgEvent.detail * -1; } 107 if ( 'wheelDelta' in orgEvent ) { deltaY = orgEvent.wheelDelta; } 108 if ( 'wheelDeltaY' in orgEvent ) { deltaY = orgEvent.wheelDeltaY; } 109 if ( 'wheelDeltaX' in orgEvent ) { deltaX = orgEvent.wheelDeltaX * -1; } 110 111 // Firefox < 17 horizontal scrolling related to DOMMouseScroll event 112 if ( 'axis' in orgEvent && orgEvent.axis === orgEvent.HORIZONTAL_AXIS ) { 113 deltaX = deltaY * -1; 114 deltaY = 0; 115 } 116 117 // Set delta to be deltaY or deltaX if deltaY is 0 for backwards compatabilitiy 118 delta = deltaY === 0 ? deltaX : deltaY; 119 120 // New school wheel delta (wheel event) 121 if ( 'deltaY' in orgEvent ) { 122 deltaY = orgEvent.deltaY * -1; 123 delta = deltaY; 124 } 125 if ( 'deltaX' in orgEvent ) { 126 deltaX = orgEvent.deltaX; 127 if ( deltaY === 0 ) { delta = deltaX * -1; } 128 } 129 130 // No change actually happened, no reason to go any further 131 if ( deltaY === 0 && deltaX === 0 ) { return; } 132 133 // Need to convert lines and pages to pixels if we aren't already in pixels 134 // There are three delta modes: 135 // * deltaMode 0 is by pixels, nothing to do 136 // * deltaMode 1 is by lines 137 // * deltaMode 2 is by pages 138 if ( orgEvent.deltaMode === 1 ) { 139 var lineHeight = $.data(this, 'mousewheel-line-height'); 140 delta *= lineHeight; 141 deltaY *= lineHeight; 142 deltaX *= lineHeight; 143 } else if ( orgEvent.deltaMode === 2 ) { 144 var pageHeight = $.data(this, 'mousewheel-page-height'); 145 delta *= pageHeight; 146 deltaY *= pageHeight; 147 deltaX *= pageHeight; 148 } 149 150 // Store lowest absolute delta to normalize the delta values 151 absDelta = Math.max( Math.abs(deltaY), Math.abs(deltaX) ); 152 153 if ( !lowestDelta || absDelta < lowestDelta ) { 154 lowestDelta = absDelta; 155 156 // Adjust older deltas if necessary 157 if ( shouldAdjustOldDeltas(orgEvent, absDelta) ) { 158 lowestDelta /= 40; 159 } 160 } 161 162 // Adjust older deltas if necessary 163 if ( shouldAdjustOldDeltas(orgEvent, absDelta) ) { 164 // Divide all the things by 40! 165 delta /= 40; 166 deltaX /= 40; 167 deltaY /= 40; 168 } 169 170 // Get a whole, normalized value for the deltas 171 delta = Math[ delta >= 1 ? 'floor' : 'ceil' ](delta / lowestDelta); 172 deltaX = Math[ deltaX >= 1 ? 'floor' : 'ceil' ](deltaX / lowestDelta); 173 deltaY = Math[ deltaY >= 1 ? 'floor' : 'ceil' ](deltaY / lowestDelta); 174 175 // Normalise offsetX and offsetY properties 176 if ( special.settings.normalizeOffset && this.getBoundingClientRect ) { 177 var boundingRect = this.getBoundingClientRect(); 178 offsetX = event.clientX - boundingRect.left; 179 offsetY = event.clientY - boundingRect.top; 180 } 181 182 // Add information to the event object 183 event.deltaX = deltaX; 184 event.deltaY = deltaY; 185 event.deltaFactor = lowestDelta; 186 event.offsetX = offsetX; 187 event.offsetY = offsetY; 188 // Go ahead and set deltaMode to 0 since we converted to pixels 189 // Although this is a little odd since we overwrite the deltaX/Y 190 // properties with normalized deltas. 191 event.deltaMode = 0; 192 193 // Add event and delta to the front of the arguments 194 args.unshift(event, delta, deltaX, deltaY); 195 196 // Clearout lowestDelta after sometime to better 197 // handle multiple device types that give different 198 // a different lowestDelta 199 // Ex: trackpad = 3 and mouse wheel = 120 200 if (nullLowestDeltaTimeout) { clearTimeout(nullLowestDeltaTimeout); } 201 nullLowestDeltaTimeout = setTimeout(nullLowestDelta, 200); 202 203 return ($.event.dispatch || $.event.handle).apply(this, args); 204 } 205 206 function nullLowestDelta() { 207 lowestDelta = null; 208 } 209 210 function shouldAdjustOldDeltas(orgEvent, absDelta) { 211 // If this is an older event and the delta is divisable by 120, 212 // then we are assuming that the browser is treating this as an 213 // older mouse wheel event and that we should divide the deltas 214 // by 40 to try and get a more usable deltaFactor. 215 // Side note, this actually impacts the reported scroll distance 216 // in older browsers and can cause scrolling to be slower than native. 217 // Turn this off by setting $.event.special.mousewheel.settings.adjustOldDeltas to false. 218 return special.settings.adjustOldDeltas && orgEvent.type === 'mousewheel' && absDelta % 120 === 0; 219 } 220 221 }));