1512 lines
43 KiB
JavaScript
Executable file
1512 lines
43 KiB
JavaScript
Executable file
/*! Picturefill - v3.0.0-rc1 - 2015-08-21
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* http://scottjehl.github.io/picturefill
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* Copyright (c) 2015 https://github.com/scottjehl/picturefill/blob/master/Authors.txt; Licensed MIT
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*/
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/*! Gecko-Picture - v1.0
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* https://github.com/scottjehl/picturefill/tree/3.0/src/plugins/gecko-picture
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* Firefox's early picture implementation (prior to FF41) is static and does
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* not react to viewport changes. This tiny module fixes this.
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*/
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(function(window) {
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/*jshint eqnull:true */
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var ua = navigator.userAgent;
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if ( window.HTMLPictureElement && ((/ecko/).test(ua) && ua.match(/rv\:(\d+)/) && RegExp.$1 < 41) ) {
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addEventListener("resize", (function() {
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var timer;
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var dummySrc = document.createElement("source");
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var fixRespimg = function(img) {
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var source, sizes;
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var picture = img.parentNode;
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if (picture.nodeName.toUpperCase() === "PICTURE") {
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source = dummySrc.cloneNode();
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picture.insertBefore(source, picture.firstElementChild);
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setTimeout(function() {
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picture.removeChild(source);
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});
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} else if (!img._pfLastSize || img.offsetWidth > img._pfLastSize) {
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img._pfLastSize = img.offsetWidth;
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sizes = img.sizes;
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img.sizes += ",100vw";
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setTimeout(function() {
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img.sizes = sizes;
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});
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}
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};
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var findPictureImgs = function() {
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var i;
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var imgs = document.querySelectorAll("picture > img, img[srcset][sizes]");
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for (i = 0; i < imgs.length; i++) {
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fixRespimg(imgs[i]);
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}
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};
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var onResize = function() {
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clearTimeout(timer);
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timer = setTimeout(findPictureImgs, 99);
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};
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var mq = window.matchMedia && matchMedia("(orientation: landscape)");
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var init = function() {
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onResize();
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if (mq && mq.addListener) {
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mq.addListener(onResize);
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}
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};
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dummySrc.srcset = "data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==";
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if (/^[c|i]|d$/.test(document.readyState || "")) {
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init();
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} else {
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document.addEventListener("DOMContentLoaded", init);
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}
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return onResize;
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})());
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}
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})(window);
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/*! Picturefill - v3.0.0-beta
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* http://scottjehl.github.io/picturefill
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* Copyright (c) 2015 https://github.com/scottjehl/picturefill/blob/master/Authors.txt;
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* License: MIT
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*/
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(function( window, document, undefined ) {
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// Enable strict mode
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"use strict";
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// HTML shim|v it for old IE (IE9 will still need the HTML video tag workaround)
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document.createElement( "picture" );
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var warn, eminpx, alwaysCheckWDescriptor, evalId;
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// local object for method references and testing exposure
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var pf = {};
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var noop = function() {};
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var image = document.createElement( "img" );
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var getImgAttr = image.getAttribute;
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var setImgAttr = image.setAttribute;
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var removeImgAttr = image.removeAttribute;
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var docElem = document.documentElement;
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var types = {};
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var cfg = {
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//resource selection:
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algorithm: ""
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};
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var srcAttr = "data-pfsrc";
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var srcsetAttr = srcAttr + "set";
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// ua sniffing is done for undetectable img loading features,
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// to do some non crucial perf optimizations
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var ua = navigator.userAgent;
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var supportAbort = (/rident/).test(ua) || ((/ecko/).test(ua) && ua.match(/rv\:(\d+)/) && RegExp.$1 > 35 );
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var curSrcProp = "currentSrc";
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var regWDesc = /\s+\+?\d+(e\d+)?w/;
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var regSize = /(\([^)]+\))?\s*(.+)/;
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var setOptions = window.picturefillCFG;
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/**
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* Shortcut property for https://w3c.github.io/webappsec/specs/mixedcontent/#restricts-mixed-content ( for easy overriding in tests )
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*/
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// baseStyle also used by getEmValue (i.e.: width: 1em is important)
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var baseStyle = "position:absolute;left:0;visibility:hidden;display:block;padding:0;border:none;font-size:1em;width:1em;overflow:hidden;clip:rect(0px, 0px, 0px, 0px)";
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var fsCss = "font-size:100%!important;";
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var isVwDirty = true;
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var cssCache = {};
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var sizeLengthCache = {};
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var DPR = window.devicePixelRatio;
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var units = {
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px: 1,
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"in": 96
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};
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var anchor = document.createElement( "a" );
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/**
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* alreadyRun flag used for setOptions. is it true setOptions will reevaluate
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* @type {boolean}
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*/
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var alreadyRun = false;
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// Reusable, non-"g" Regexes
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// (Don't use \s, to avoid matching non-breaking space.)
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var regexLeadingSpaces = /^[ \t\n\r\u000c]+/,
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regexLeadingCommasOrSpaces = /^[, \t\n\r\u000c]+/,
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regexLeadingNotSpaces = /^[^ \t\n\r\u000c]+/,
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regexTrailingCommas = /[,]+$/,
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regexNonNegativeInteger = /^\d+$/,
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// ( Positive or negative or unsigned integers or decimals, without or without exponents.
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// Must include at least one digit.
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// According to spec tests any decimal point must be followed by a digit.
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// No leading plus sign is allowed.)
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// https://html.spec.whatwg.org/multipage/infrastructure.html#valid-floating-point-number
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regexFloatingPoint = /^-?(?:[0-9]+|[0-9]*\.[0-9]+)(?:[eE][+-]?[0-9]+)?$/;
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var on = function(obj, evt, fn, capture) {
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if ( obj.addEventListener ) {
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obj.addEventListener(evt, fn, capture || false);
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} else if ( obj.attachEvent ) {
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obj.attachEvent( "on" + evt, fn);
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}
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};
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/**
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* simple memoize function:
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*/
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var memoize = function(fn) {
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var cache = {};
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return function(input) {
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if ( !(input in cache) ) {
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cache[ input ] = fn(input);
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}
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return cache[ input ];
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};
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};
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// UTILITY FUNCTIONS
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// Manual is faster than RegEx
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// http://jsperf.com/whitespace-character/5
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function isSpace(c) {
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return (c === "\u0020" || // space
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c === "\u0009" || // horizontal tab
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c === "\u000A" || // new line
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c === "\u000C" || // form feed
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c === "\u000D"); // carriage return
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}
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/**
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* gets a mediaquery and returns a boolean or gets a css length and returns a number
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* @param css mediaqueries or css length
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* @returns {boolean|number}
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*
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* based on: https://gist.github.com/jonathantneal/db4f77009b155f083738
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*/
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var evalCSS = (function() {
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var regLength = /^([\d\.]+)(em|vw|px)$/;
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var replace = function() {
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var args = arguments, index = 0, string = args[0];
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while (++index in args) {
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string = string.replace(args[index], args[++index]);
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}
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return string;
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};
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var buildStr = memoize(function(css) {
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return "return " + replace((css || "").toLowerCase(),
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// interpret `and`
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/\band\b/g, "&&",
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// interpret `,`
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/,/g, "||",
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// interpret `min-` as >=
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/min-([a-z-\s]+):/g, "e.$1>=",
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// interpret `max-` as <=
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/max-([a-z-\s]+):/g, "e.$1<=",
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//calc value
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/calc([^)]+)/g, "($1)",
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// interpret css values
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/(\d+[\.]*[\d]*)([a-z]+)/g, "($1 * e.$2)",
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//make eval less evil
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/^(?!(e.[a-z]|[0-9\.&=|><\+\-\*\(\)\/])).*/ig, ""
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) + ";";
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});
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return function(css, length) {
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var parsedLength;
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if (!(css in cssCache)) {
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cssCache[css] = false;
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if (length && (parsedLength = css.match( regLength ))) {
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cssCache[css] = parsedLength[ 1 ] * units[parsedLength[ 2 ]];
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} else {
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/*jshint evil:true */
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try{
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cssCache[css] = new Function("e", buildStr(css))(units);
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} catch(e) {}
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/*jshint evil:false */
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}
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}
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return cssCache[css];
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};
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})();
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var setResolution = function( candidate, sizesattr ) {
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if ( candidate.w ) { // h = means height: || descriptor.type === 'h' do not handle yet...
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candidate.cWidth = pf.calcListLength( sizesattr || "100vw" );
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candidate.res = candidate.w / candidate.cWidth ;
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} else {
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candidate.res = candidate.d;
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}
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return candidate;
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};
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/**
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*
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* @param opt
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*/
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var picturefill = function( opt ) {
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var elements, i, plen;
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var options = opt || {};
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if ( options.elements && options.elements.nodeType === 1 ) {
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if ( options.elements.nodeName.toUpperCase() === "IMG" ) {
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options.elements = [ options.elements ];
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} else {
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options.context = options.elements;
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options.elements = null;
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}
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}
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elements = options.elements || pf.qsa( (options.context || document), ( options.reevaluate || options.reselect ) ? pf.sel : pf.selShort );
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if ( (plen = elements.length) ) {
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pf.setupRun( options );
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alreadyRun = true;
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// Loop through all elements
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for ( i = 0; i < plen; i++ ) {
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pf.fillImg(elements[ i ], options);
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}
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pf.teardownRun( options );
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}
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};
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/**
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* outputs a warning for the developer
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* @param {message}
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* @type {Function}
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*/
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warn = ( window.console && console.warn ) ?
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function( message ) {
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console.warn( message );
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} :
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noop
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;
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if ( !(curSrcProp in image) ) {
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curSrcProp = "src";
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}
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// Add support for standard mime types.
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types[ "image/jpeg" ] = true;
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types[ "image/gif" ] = true;
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types[ "image/png" ] = true;
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function detectTypeSupport( type, typeUri ) {
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// based on Modernizr's lossless img-webp test
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// note: asynchronous
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var image = new window.Image();
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image.onerror = function() {
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types[ type ] = false;
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picturefill();
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};
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image.onload = function() {
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types[ type ] = image.width === 1;
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picturefill();
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};
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image.src = typeUri;
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return "pending";
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}
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// test svg support
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types[ "image/svg+xml" ] = document.implementation.hasFeature( "http://wwwindow.w3.org/TR/SVG11/feature#Image", "1.1" );
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/**
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* updates the internal vW property with the current viewport width in px
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*/
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function updateMetrics() {
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isVwDirty = false;
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DPR = window.devicePixelRatio;
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cssCache = {};
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sizeLengthCache = {};
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pf.DPR = DPR || 1;
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units.width = Math.max(window.innerWidth || 0, docElem.clientWidth);
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units.height = Math.max(window.innerHeight || 0, docElem.clientHeight);
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units.vw = units.width / 100;
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units.vh = units.height / 100;
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evalId = [ units.height, units.width, DPR ].join("-");
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units.em = pf.getEmValue();
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units.rem = units.em;
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}
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function chooseLowRes( lowerValue, higherValue, dprValue, isCached ) {
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var bonusFactor, tooMuch, bonus, meanDensity;
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//experimental
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if (cfg.algorithm === "saveData" ){
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if ( lowerValue > 2.7 ) {
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meanDensity = dprValue + 1;
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} else {
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tooMuch = higherValue - dprValue;
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bonusFactor = Math.pow(lowerValue - 0.6, 1.5);
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bonus = tooMuch * bonusFactor;
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if (isCached) {
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bonus += 0.1 * bonusFactor;
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}
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meanDensity = lowerValue + bonus;
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}
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} else {
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meanDensity = (dprValue > 1) ?
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Math.sqrt(lowerValue * higherValue) :
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lowerValue;
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}
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return meanDensity > dprValue;
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}
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function applyBestCandidate( img ) {
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var srcSetCandidates;
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var matchingSet = pf.getSet( img );
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var evaluated = false;
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if ( matchingSet !== "pending" ) {
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evaluated = evalId;
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if ( matchingSet ) {
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srcSetCandidates = pf.setRes( matchingSet );
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pf.applySetCandidate( srcSetCandidates, img );
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}
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}
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img[ pf.ns ].evaled = evaluated;
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}
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function ascendingSort( a, b ) {
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return a.res - b.res;
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}
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function setSrcToCur( img, src, set ) {
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var candidate;
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if ( !set && src ) {
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set = img[ pf.ns ].sets;
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set = set && set[set.length - 1];
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}
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candidate = getCandidateForSrc(src, set);
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if ( candidate ) {
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src = pf.makeUrl(src);
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img[ pf.ns ].curSrc = src;
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img[ pf.ns ].curCan = candidate;
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if ( !candidate.res ) {
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setResolution( candidate, candidate.set.sizes );
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}
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}
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return candidate;
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}
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function getCandidateForSrc( src, set ) {
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var i, candidate, candidates;
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if ( src && set ) {
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candidates = pf.parseSet( set );
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src = pf.makeUrl(src);
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for ( i = 0; i < candidates.length; i++ ) {
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if ( src === pf.makeUrl(candidates[ i ].url) ) {
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candidate = candidates[ i ];
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break;
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}
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}
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}
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return candidate;
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}
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function getAllSourceElements( picture, candidates ) {
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var i, len, source, srcset;
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// SPEC mismatch intended for size and perf:
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// actually only source elements preceding the img should be used
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// also note: don't use qsa here, because IE8 sometimes doesn't like source as the key part in a selector
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var sources = picture.getElementsByTagName( "source" );
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for ( i = 0, len = sources.length; i < len; i++ ) {
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source = sources[ i ];
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source[ pf.ns ] = true;
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srcset = source.getAttribute( "srcset" );
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// if source does not have a srcset attribute, skip
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if ( srcset ) {
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candidates.push( {
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srcset: srcset,
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media: source.getAttribute( "media" ),
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type: source.getAttribute( "type" ),
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sizes: source.getAttribute( "sizes" )
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} );
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}
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}
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}
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|
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/**
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* Srcset Parser
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* By Alex Bell | MIT License
|
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*
|
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* @returns Array [{url: _, d: _, w: _, h:_, set:_(????)}, ...]
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*
|
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* Based super duper closely on the reference algorithm at:
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* https://html.spec.whatwg.org/multipage/embedded-content.html#parse-a-srcset-attribute
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*/
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// 1. Let input be the value passed to this algorithm.
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// (TO-DO : Explain what "set" argument is here. Maybe choose a more
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// descriptive & more searchable name. Since passing the "set" in really has
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// nothing to do with parsing proper, I would prefer this assignment eventually
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// go in an external fn.)
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function parseSrcset(input, set) {
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function collectCharacters(regEx) {
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var chars,
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match = regEx.exec(input.substring(pos));
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|
if (match) {
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chars = match[ 0 ];
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pos += chars.length;
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return chars;
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}
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}
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var inputLength = input.length,
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url,
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descriptors,
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currentDescriptor,
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state,
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c,
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// 2. Let position be a pointer into input, initially pointing at the start
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// of the string.
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pos = 0,
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// 3. Let candidates be an initially empty source set.
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candidates = [];
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/**
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* Adds descriptor properties to a candidate, pushes to the candidates array
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* @return undefined
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*/
|
|
// (Declared outside of the while loop so that it's only created once.
|
|
// (This fn is defined before it is used, in order to pass JSHINT.
|
|
// Unfortunately this breaks the sequencing of the spec comments. :/ )
|
|
function parseDescriptors() {
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|
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// 9. Descriptor parser: Let error be no.
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var pError = false,
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|
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// 10. Let width be absent.
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// 11. Let density be absent.
|
|
// 12. Let future-compat-h be absent. (We're implementing it now as h)
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w, d, h, i,
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candidate = {},
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desc, lastChar, value, intVal, floatVal;
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|
|
// 13. For each descriptor in descriptors, run the appropriate set of steps
|
|
// from the following list:
|
|
for (i = 0 ; i < descriptors.length; i++) {
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desc = descriptors[ i ];
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|
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lastChar = desc[ desc.length - 1 ];
|
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value = desc.substring(0, desc.length - 1);
|
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intVal = parseInt(value, 10);
|
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floatVal = parseFloat(value);
|
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|
|
// If the descriptor consists of a valid non-negative integer followed by
|
|
// a U+0077 LATIN SMALL LETTER W character
|
|
if (regexNonNegativeInteger.test(value) && (lastChar === "w")) {
|
|
|
|
// If width and density are not both absent, then let error be yes.
|
|
if (w || d) {pError = true;}
|
|
|
|
// Apply the rules for parsing non-negative integers to the descriptor.
|
|
// If the result is zero, let error be yes.
|
|
// Otherwise, let width be the result.
|
|
if (intVal === 0) {pError = true;} else {w = intVal;}
|
|
|
|
// If the descriptor consists of a valid floating-point number followed by
|
|
// a U+0078 LATIN SMALL LETTER X character
|
|
} else if (regexFloatingPoint.test(value) && (lastChar === "x")) {
|
|
|
|
// If width, density and future-compat-h are not all absent, then let error
|
|
// be yes.
|
|
if (w || d || h) {pError = true;}
|
|
|
|
// Apply the rules for parsing floating-point number values to the descriptor.
|
|
// If the result is less than zero, let error be yes. Otherwise, let density
|
|
// be the result.
|
|
if (floatVal < 0) {pError = true;} else {d = floatVal;}
|
|
|
|
// If the descriptor consists of a valid non-negative integer followed by
|
|
// a U+0068 LATIN SMALL LETTER H character
|
|
} else if (regexNonNegativeInteger.test(value) && (lastChar === "h")) {
|
|
|
|
// If height and density are not both absent, then let error be yes.
|
|
if (h || d) {pError = true;}
|
|
|
|
// Apply the rules for parsing non-negative integers to the descriptor.
|
|
// If the result is zero, let error be yes. Otherwise, let future-compat-h
|
|
// be the result.
|
|
if (intVal === 0) {pError = true;} else {h = intVal;}
|
|
|
|
// Anything else, Let error be yes.
|
|
} else {pError = true;}
|
|
} // (close step 13 for loop)
|
|
|
|
// 15. If error is still no, then append a new image source to candidates whose
|
|
// URL is url, associated with a width width if not absent and a pixel
|
|
// density density if not absent. Otherwise, there is a parse error.
|
|
if (!pError) {
|
|
candidate.url = url;
|
|
|
|
if (w) { candidate.w = w;}
|
|
if (d) { candidate.d = d;}
|
|
if (h) { candidate.h = h;}
|
|
if (!h && !d && !w) {candidate.d = 1;}
|
|
if (candidate.d === 1) {set.has1x = true;}
|
|
candidate.set = set;
|
|
|
|
candidates.push(candidate);
|
|
}
|
|
} // (close parseDescriptors fn)
|
|
|
|
/**
|
|
* Tokenizes descriptor properties prior to parsing
|
|
* Returns undefined.
|
|
* (Again, this fn is defined before it is used, in order to pass JSHINT.
|
|
* Unfortunately this breaks the logical sequencing of the spec comments. :/ )
|
|
*/
|
|
function tokenize() {
|
|
|
|
// 8.1. Descriptor tokeniser: Skip whitespace
|
|
collectCharacters(regexLeadingSpaces);
|
|
|
|
// 8.2. Let current descriptor be the empty string.
|
|
currentDescriptor = "";
|
|
|
|
// 8.3. Let state be in descriptor.
|
|
state = "in descriptor";
|
|
|
|
while (true) {
|
|
|
|
// 8.4. Let c be the character at position.
|
|
c = input.charAt(pos);
|
|
|
|
// Do the following depending on the value of state.
|
|
// For the purpose of this step, "EOF" is a special character representing
|
|
// that position is past the end of input.
|
|
|
|
// In descriptor
|
|
if (state === "in descriptor") {
|
|
// Do the following, depending on the value of c:
|
|
|
|
// Space character
|
|
// If current descriptor is not empty, append current descriptor to
|
|
// descriptors and let current descriptor be the empty string.
|
|
// Set state to after descriptor.
|
|
if (isSpace(c)) {
|
|
if (currentDescriptor) {
|
|
descriptors.push(currentDescriptor);
|
|
currentDescriptor = "";
|
|
state = "after descriptor";
|
|
}
|
|
|
|
// U+002C COMMA (,)
|
|
// Advance position to the next character in input. If current descriptor
|
|
// is not empty, append current descriptor to descriptors. Jump to the step
|
|
// labeled descriptor parser.
|
|
} else if (c === ",") {
|
|
pos += 1;
|
|
if (currentDescriptor) {
|
|
descriptors.push(currentDescriptor);
|
|
}
|
|
parseDescriptors();
|
|
return;
|
|
|
|
// U+0028 LEFT PARENTHESIS (()
|
|
// Append c to current descriptor. Set state to in parens.
|
|
} else if (c === "\u0028") {
|
|
currentDescriptor = currentDescriptor + c;
|
|
state = "in parens";
|
|
|
|
// EOF
|
|
// If current descriptor is not empty, append current descriptor to
|
|
// descriptors. Jump to the step labeled descriptor parser.
|
|
} else if (c === "") {
|
|
if (currentDescriptor) {
|
|
descriptors.push(currentDescriptor);
|
|
}
|
|
parseDescriptors();
|
|
return;
|
|
|
|
// Anything else
|
|
// Append c to current descriptor.
|
|
} else {
|
|
currentDescriptor = currentDescriptor + c;
|
|
}
|
|
// (end "in descriptor"
|
|
|
|
// In parens
|
|
} else if (state === "in parens") {
|
|
|
|
// U+0029 RIGHT PARENTHESIS ())
|
|
// Append c to current descriptor. Set state to in descriptor.
|
|
if (c === ")") {
|
|
currentDescriptor = currentDescriptor + c;
|
|
state = "in descriptor";
|
|
|
|
// EOF
|
|
// Append current descriptor to descriptors. Jump to the step labeled
|
|
// descriptor parser.
|
|
} else if (c === "") {
|
|
descriptors.push(currentDescriptor);
|
|
parseDescriptors();
|
|
return;
|
|
|
|
// Anything else
|
|
// Append c to current descriptor.
|
|
} else {
|
|
currentDescriptor = currentDescriptor + c;
|
|
}
|
|
|
|
// After descriptor
|
|
} else if (state === "after descriptor") {
|
|
|
|
// Do the following, depending on the value of c:
|
|
// Space character: Stay in this state.
|
|
if (isSpace(c)) {
|
|
|
|
// EOF: Jump to the step labeled descriptor parser.
|
|
} else if (c === "") {
|
|
parseDescriptors();
|
|
return;
|
|
|
|
// Anything else
|
|
// Set state to in descriptor. Set position to the previous character in input.
|
|
} else {
|
|
state = "in descriptor";
|
|
pos -= 1;
|
|
|
|
}
|
|
}
|
|
|
|
// Advance position to the next character in input.
|
|
pos += 1;
|
|
|
|
// Repeat this step.
|
|
} // (close while true loop)
|
|
}
|
|
|
|
// 4. Splitting loop: Collect a sequence of characters that are space
|
|
// characters or U+002C COMMA characters. If any U+002C COMMA characters
|
|
// were collected, that is a parse error.
|
|
while (true) {
|
|
collectCharacters(regexLeadingCommasOrSpaces);
|
|
|
|
// 5. If position is past the end of input, return candidates and abort these steps.
|
|
if (pos >= inputLength) {
|
|
return candidates; // (we're done, this is the sole return path)
|
|
}
|
|
|
|
// 6. Collect a sequence of characters that are not space characters,
|
|
// and let that be url.
|
|
url = collectCharacters(regexLeadingNotSpaces);
|
|
|
|
// 7. Let descriptors be a new empty list.
|
|
descriptors = [];
|
|
|
|
// 8. If url ends with a U+002C COMMA character (,), follow these substeps:
|
|
// (1). Remove all trailing U+002C COMMA characters from url. If this removed
|
|
// more than one character, that is a parse error.
|
|
if (url.slice(-1) === ",") {
|
|
url = url.replace(regexTrailingCommas, "");
|
|
// (Jump ahead to step 9 to skip tokenization and just push the candidate).
|
|
parseDescriptors();
|
|
|
|
// Otherwise, follow these substeps:
|
|
} else {
|
|
tokenize();
|
|
} // (close else of step 8)
|
|
|
|
// 16. Return to the step labeled splitting loop.
|
|
} // (Close of big while loop.)
|
|
}
|
|
|
|
/*
|
|
* Sizes Parser
|
|
*
|
|
* By Alex Bell | MIT License
|
|
*
|
|
* Non-strict but accurate and lightweight JS Parser for the string value <img sizes="here">
|
|
*
|
|
* Reference algorithm at:
|
|
* https://html.spec.whatwg.org/multipage/embedded-content.html#parse-a-sizes-attribute
|
|
*
|
|
* Most comments are copied in directly from the spec
|
|
* (except for comments in parens).
|
|
*
|
|
* Grammar is:
|
|
* <source-size-list> = <source-size># [ , <source-size-value> ]? | <source-size-value>
|
|
* <source-size> = <media-condition> <source-size-value>
|
|
* <source-size-value> = <length>
|
|
* http://www.w3.org/html/wg/drafts/html/master/embedded-content.html#attr-img-sizes
|
|
*
|
|
* E.g. "(max-width: 30em) 100vw, (max-width: 50em) 70vw, 100vw"
|
|
* or "(min-width: 30em), calc(30vw - 15px)" or just "30vw"
|
|
*
|
|
* Returns the first valid <css-length> with a media condition that evaluates to true,
|
|
* or "100vw" if all valid media conditions evaluate to false.
|
|
*
|
|
*/
|
|
|
|
function parseSizes(strValue) {
|
|
|
|
// (Percentage CSS lengths are not allowed in this case, to avoid confusion:
|
|
// https://html.spec.whatwg.org/multipage/embedded-content.html#valid-source-size-list
|
|
// CSS allows a single optional plus or minus sign:
|
|
// http://www.w3.org/TR/CSS2/syndata.html#numbers
|
|
// CSS is ASCII case-insensitive:
|
|
// http://www.w3.org/TR/CSS2/syndata.html#characters )
|
|
// Spec allows exponential notation for <number> type:
|
|
// http://dev.w3.org/csswg/css-values/#numbers
|
|
var regexCssLengthWithUnits = /^(?:[+-]?[0-9]+|[0-9]*\.[0-9]+)(?:[eE][+-]?[0-9]+)?(?:ch|cm|em|ex|in|mm|pc|pt|px|rem|vh|vmin|vmax|vw)$/i;
|
|
|
|
// (This is a quick and lenient test. Because of optional unlimited-depth internal
|
|
// grouping parens and strict spacing rules, this could get very complicated.)
|
|
var regexCssCalc = /^calc\((?:[0-9a-z \.\+\-\*\/\(\)]+)\)$/i;
|
|
|
|
var i;
|
|
var unparsedSizesList;
|
|
var unparsedSizesListLength;
|
|
var unparsedSize;
|
|
var lastComponentValue;
|
|
var size;
|
|
|
|
// UTILITY FUNCTIONS
|
|
|
|
// (Toy CSS parser. The goals here are:
|
|
// 1) expansive test coverage without the weight of a full CSS parser.
|
|
// 2) Avoiding regex wherever convenient.
|
|
// Quick tests: http://jsfiddle.net/gtntL4gr/3/
|
|
// Returns an array of arrays.)
|
|
function parseComponentValues(str) {
|
|
var chrctr;
|
|
var component = "";
|
|
var componentArray = [];
|
|
var listArray = [];
|
|
var parenDepth = 0;
|
|
var pos = 0;
|
|
var inComment = false;
|
|
|
|
function pushComponent() {
|
|
if (component) {
|
|
componentArray.push(component);
|
|
component = "";
|
|
}
|
|
}
|
|
|
|
function pushComponentArray() {
|
|
if (componentArray[0]) {
|
|
listArray.push(componentArray);
|
|
componentArray = [];
|
|
}
|
|
}
|
|
|
|
// (Loop forwards from the beginning of the string.)
|
|
while (true) {
|
|
chrctr = str.charAt(pos);
|
|
|
|
if (chrctr === "") { // ( End of string reached.)
|
|
pushComponent();
|
|
pushComponentArray();
|
|
return listArray;
|
|
} else if (inComment) {
|
|
if ((chrctr === "*") && (str[pos + 1] === "/")) { // (At end of a comment.)
|
|
inComment = false;
|
|
pos += 2;
|
|
pushComponent();
|
|
continue;
|
|
} else {
|
|
pos += 1; // (Skip all characters inside comments.)
|
|
continue;
|
|
}
|
|
} else if (isSpace(chrctr)) {
|
|
// (If previous character in loop was also a space, or if
|
|
// at the beginning of the string, do not add space char to
|
|
// component.)
|
|
if ( (str.charAt(pos - 1) && isSpace( str.charAt(pos - 1) ) ) || !component ) {
|
|
pos += 1;
|
|
continue;
|
|
} else if (parenDepth === 0) {
|
|
pushComponent();
|
|
pos +=1;
|
|
continue;
|
|
} else {
|
|
// (Replace any space character with a plain space for legibility.)
|
|
chrctr = " ";
|
|
}
|
|
} else if (chrctr === "(") {
|
|
parenDepth += 1;
|
|
} else if (chrctr === ")") {
|
|
parenDepth -= 1;
|
|
} else if (chrctr === ",") {
|
|
pushComponent();
|
|
pushComponentArray();
|
|
pos += 1;
|
|
continue;
|
|
} else if ( (chrctr === "/") && (str.charAt(pos + 1) === "*") ) {
|
|
inComment = true;
|
|
pos += 2;
|
|
continue;
|
|
}
|
|
|
|
component = component + chrctr;
|
|
pos += 1;
|
|
}
|
|
}
|
|
|
|
function isValidNonNegativeSourceSizeValue(s) {
|
|
if (regexCssLengthWithUnits.test(s) && (parseFloat(s) >= 0)) {return true;}
|
|
if (regexCssCalc.test(s)) {return true;}
|
|
// ( http://www.w3.org/TR/CSS2/syndata.html#numbers says:
|
|
// "-0 is equivalent to 0 and is not a negative number." which means that
|
|
// unitless zero and unitless negative zero must be accepted as special cases.)
|
|
if ((s === "0") || (s === "-0") || (s === "+0")) {return true;}
|
|
return false;
|
|
}
|
|
|
|
// When asked to parse a sizes attribute from an element, parse a
|
|
// comma-separated list of component values from the value of the element's
|
|
// sizes attribute (or the empty string, if the attribute is absent), and let
|
|
// unparsed sizes list be the result.
|
|
// http://dev.w3.org/csswg/css-syntax/#parse-comma-separated-list-of-component-values
|
|
|
|
unparsedSizesList = parseComponentValues(strValue);
|
|
unparsedSizesListLength = unparsedSizesList.length;
|
|
|
|
// For each unparsed size in unparsed sizes list:
|
|
for (i = 0; i < unparsedSizesListLength; i++) {
|
|
unparsedSize = unparsedSizesList[i];
|
|
|
|
// 1. Remove all consecutive <whitespace-token>s from the end of unparsed size.
|
|
// ( parseComponentValues() already omits spaces outside of parens. )
|
|
|
|
// If unparsed size is now empty, that is a parse error; continue to the next
|
|
// iteration of this algorithm.
|
|
// ( parseComponentValues() won't push an empty array. )
|
|
|
|
// 2. If the last component value in unparsed size is a valid non-negative
|
|
// <source-size-value>, let size be its value and remove the component value
|
|
// from unparsed size. Any CSS function other than the calc() function is
|
|
// invalid. Otherwise, there is a parse error; continue to the next iteration
|
|
// of this algorithm.
|
|
// http://dev.w3.org/csswg/css-syntax/#parse-component-value
|
|
lastComponentValue = unparsedSize[unparsedSize.length - 1];
|
|
|
|
if (isValidNonNegativeSourceSizeValue(lastComponentValue)) {
|
|
size = lastComponentValue;
|
|
unparsedSize.pop();
|
|
} else {
|
|
continue;
|
|
}
|
|
|
|
// 3. Remove all consecutive <whitespace-token>s from the end of unparsed
|
|
// size. If unparsed size is now empty, return size and exit this algorithm.
|
|
// If this was not the last item in unparsed sizes list, that is a parse error.
|
|
if (unparsedSize.length === 0) {
|
|
return size;
|
|
}
|
|
|
|
// 4. Parse the remaining component values in unparsed size as a
|
|
// <media-condition>. If it does not parse correctly, or it does parse
|
|
// correctly but the <media-condition> evaluates to false, continue to the
|
|
// next iteration of this algorithm.
|
|
// (Parsing all possible compound media conditions in JS is heavy, complicated,
|
|
// and the payoff is unclear. Is there ever an situation where the
|
|
// media condition parses incorrectly but still somehow evaluates to true?
|
|
// Can we just rely on the browser/polyfill to do it?)
|
|
unparsedSize = unparsedSize.join(" ");
|
|
if (!(pf.matchesMedia( unparsedSize ) ) ) {
|
|
continue;
|
|
}
|
|
|
|
// 5. Return size and exit this algorithm.
|
|
return size;
|
|
}
|
|
|
|
// If the above algorithm exhausts unparsed sizes list without returning a
|
|
// size value, return 100vw.
|
|
return "100vw";
|
|
}
|
|
|
|
// namespace
|
|
pf.ns = ("pf" + new Date().getTime()).substr(0, 9);
|
|
|
|
// srcset support test
|
|
pf.supSrcset = "srcset" in image;
|
|
pf.supSizes = "sizes" in image;
|
|
pf.supPicture = !!window.HTMLPictureElement;
|
|
|
|
if (pf.supSrcset && pf.supPicture && !pf.supSizes) {
|
|
(function(image2) {
|
|
image.srcset = "data:,a";
|
|
image2.src = "data:,a";
|
|
pf.supSrcset = image.complete === image2.complete;
|
|
pf.supPicture = pf.supSrcset && pf.supPicture;
|
|
})(document.createElement("img"));
|
|
}
|
|
|
|
// using pf.qsa instead of dom traversing does scale much better,
|
|
// especially on sites mixing responsive and non-responsive images
|
|
pf.selShort = "picture>img,img[srcset]";
|
|
pf.sel = pf.selShort;
|
|
pf.cfg = cfg;
|
|
|
|
if ( pf.supSrcset ) {
|
|
pf.sel += ",img[" + srcsetAttr + "]";
|
|
}
|
|
|
|
/**
|
|
* Shortcut property for `devicePixelRatio` ( for easy overriding in tests )
|
|
*/
|
|
pf.DPR = (DPR || 1 );
|
|
pf.u = units;
|
|
|
|
// container of supported mime types that one might need to qualify before using
|
|
pf.types = types;
|
|
|
|
alwaysCheckWDescriptor = pf.supSrcset && !pf.supSizes;
|
|
|
|
pf.setSize = noop;
|
|
|
|
/**
|
|
* Gets a string and returns the absolute URL
|
|
* @param src
|
|
* @returns {String} absolute URL
|
|
*/
|
|
|
|
pf.makeUrl = memoize(function(src) {
|
|
anchor.href = src;
|
|
return anchor.href;
|
|
});
|
|
|
|
/**
|
|
* Gets a DOM element or document and a selctor and returns the found matches
|
|
* Can be extended with jQuery/Sizzle for IE7 support
|
|
* @param context
|
|
* @param sel
|
|
* @returns {NodeList}
|
|
*/
|
|
pf.qsa = function(context, sel) {
|
|
return context.querySelectorAll(sel);
|
|
};
|
|
|
|
/**
|
|
* Shortcut method for matchMedia ( for easy overriding in tests )
|
|
* wether native or pf.mMQ is used will be decided lazy on first call
|
|
* @returns {boolean}
|
|
*/
|
|
pf.matchesMedia = function() {
|
|
if ( window.matchMedia && (matchMedia( "(min-width: 0.1em)" ) || {}).matches ) {
|
|
pf.matchesMedia = function( media ) {
|
|
return !media || ( matchMedia( media ).matches );
|
|
};
|
|
} else {
|
|
pf.matchesMedia = pf.mMQ;
|
|
}
|
|
|
|
return pf.matchesMedia.apply( this, arguments );
|
|
};
|
|
|
|
/**
|
|
* A simplified matchMedia implementation for IE8 and IE9
|
|
* handles only min-width/max-width with px or em values
|
|
* @param media
|
|
* @returns {boolean}
|
|
*/
|
|
pf.mMQ = function( media ) {
|
|
return media ? evalCSS(media) : true;
|
|
};
|
|
|
|
/**
|
|
* Returns the calculated length in css pixel from the given sourceSizeValue
|
|
* http://dev.w3.org/csswg/css-values-3/#length-value
|
|
* intended Spec mismatches:
|
|
* * Does not check for invalid use of CSS functions
|
|
* * Does handle a computed length of 0 the same as a negative and therefore invalid value
|
|
* @param sourceSizeValue
|
|
* @returns {Number}
|
|
*/
|
|
pf.calcLength = function( sourceSizeValue ) {
|
|
|
|
var value = evalCSS(sourceSizeValue, true) || false;
|
|
if (value < 0) {
|
|
value = false;
|
|
}
|
|
|
|
return value;
|
|
};
|
|
|
|
/**
|
|
* Takes a type string and checks if its supported
|
|
*/
|
|
|
|
pf.supportsType = function( type ) {
|
|
return ( type ) ? types[ type ] : true;
|
|
};
|
|
|
|
/**
|
|
* Parses a sourceSize into mediaCondition (media) and sourceSizeValue (length)
|
|
* @param sourceSizeStr
|
|
* @returns {*}
|
|
*/
|
|
pf.parseSize = memoize(function( sourceSizeStr ) {
|
|
var match = ( sourceSizeStr || "" ).match(regSize);
|
|
return {
|
|
media: match && match[1],
|
|
length: match && match[2]
|
|
};
|
|
});
|
|
|
|
pf.parseSet = function( set ) {
|
|
if ( !set.cands ) {
|
|
set.cands = parseSrcset(set.srcset, set);
|
|
}
|
|
return set.cands;
|
|
};
|
|
|
|
/**
|
|
* returns 1em in css px for html/body default size
|
|
* function taken from respondjs
|
|
* @returns {*|number}
|
|
*/
|
|
pf.getEmValue = function() {
|
|
var body;
|
|
if ( !eminpx && (body = document.body) ) {
|
|
var div = document.createElement( "div" ),
|
|
originalHTMLCSS = docElem.style.cssText,
|
|
originalBodyCSS = body.style.cssText;
|
|
|
|
div.style.cssText = baseStyle;
|
|
|
|
// 1em in a media query is the value of the default font size of the browser
|
|
// reset docElem and body to ensure the correct value is returned
|
|
docElem.style.cssText = fsCss;
|
|
body.style.cssText = fsCss;
|
|
|
|
body.appendChild( div );
|
|
eminpx = div.offsetWidth;
|
|
body.removeChild( div );
|
|
|
|
//also update eminpx before returning
|
|
eminpx = parseFloat( eminpx, 10 );
|
|
|
|
// restore the original values
|
|
docElem.style.cssText = originalHTMLCSS;
|
|
body.style.cssText = originalBodyCSS;
|
|
|
|
}
|
|
return eminpx || 16;
|
|
};
|
|
|
|
/**
|
|
* Takes a string of sizes and returns the width in pixels as a number
|
|
*/
|
|
pf.calcListLength = function( sourceSizeListStr ) {
|
|
// Split up source size list, ie ( max-width: 30em ) 100%, ( max-width: 50em ) 50%, 33%
|
|
//
|
|
// or (min-width:30em) calc(30% - 15px)
|
|
if ( !(sourceSizeListStr in sizeLengthCache) || cfg.uT ) {
|
|
var winningLength = pf.calcLength( parseSizes( sourceSizeListStr ) );
|
|
|
|
sizeLengthCache[ sourceSizeListStr ] = !winningLength ? units.width : winningLength;
|
|
}
|
|
|
|
return sizeLengthCache[ sourceSizeListStr ];
|
|
};
|
|
|
|
/**
|
|
* Takes a candidate object with a srcset property in the form of url/
|
|
* ex. "images/pic-medium.png 1x, images/pic-medium-2x.png 2x" or
|
|
* "images/pic-medium.png 400w, images/pic-medium-2x.png 800w" or
|
|
* "images/pic-small.png"
|
|
* Get an array of image candidates in the form of
|
|
* {url: "/foo/bar.png", resolution: 1}
|
|
* where resolution is http://dev.w3.org/csswg/css-values-3/#resolution-value
|
|
* If sizes is specified, res is calculated
|
|
*/
|
|
pf.setRes = function( set ) {
|
|
var candidates;
|
|
if ( set ) {
|
|
|
|
candidates = pf.parseSet( set );
|
|
|
|
for ( var i = 0, len = candidates.length; i < len; i++ ) {
|
|
setResolution( candidates[ i ], set.sizes );
|
|
}
|
|
}
|
|
return candidates;
|
|
};
|
|
|
|
pf.setRes.res = setResolution;
|
|
|
|
pf.applySetCandidate = function( candidates, img ) {
|
|
if ( !candidates.length ) {return;}
|
|
var candidate,
|
|
i,
|
|
j,
|
|
length,
|
|
bestCandidate,
|
|
curSrc,
|
|
curCan,
|
|
isSameSet,
|
|
candidateSrc,
|
|
abortCurSrc;
|
|
|
|
var imageData = img[ pf.ns ];
|
|
var dpr = pf.DPR;
|
|
|
|
curSrc = imageData.curSrc || img[curSrcProp];
|
|
|
|
curCan = imageData.curCan || setSrcToCur(img, curSrc, candidates[0].set);
|
|
|
|
// if we have a current source, we might either become lazy or give this source some advantage
|
|
if ( curCan && curCan.set === candidates[ 0 ].set ) {
|
|
|
|
// if browser can abort image request and the image has a higher pixel density than needed
|
|
// and this image isn't downloaded yet, we skip next part and try to save bandwidth
|
|
abortCurSrc = (supportAbort && !img.complete && curCan.res - 0.1 > dpr);
|
|
|
|
if ( !abortCurSrc ) {
|
|
curCan.cached = true;
|
|
|
|
// if current candidate is "best", "better" or "okay",
|
|
// set it to bestCandidate
|
|
if ( curCan && isSameSet && curCan.res >= dpr ) {
|
|
bestCandidate = curCan;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ( !bestCandidate ) {
|
|
|
|
candidates.sort( ascendingSort );
|
|
|
|
length = candidates.length;
|
|
bestCandidate = candidates[ length - 1 ];
|
|
|
|
for ( i = 0; i < length; i++ ) {
|
|
candidate = candidates[ i ];
|
|
if ( candidate.res >= dpr ) {
|
|
j = i - 1;
|
|
|
|
// we have found the perfect candidate,
|
|
// but let's improve this a little bit with some assumptions ;-)
|
|
if (candidates[ j ] &&
|
|
(abortCurSrc || curSrc !== pf.makeUrl( candidate.url )) &&
|
|
chooseLowRes(candidates[ j ].res, candidate.res, dpr, candidates[ j ].cached)) {
|
|
|
|
bestCandidate = candidates[ j ];
|
|
|
|
} else {
|
|
bestCandidate = candidate;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if ( bestCandidate ) {
|
|
|
|
candidateSrc = pf.makeUrl( bestCandidate.url );
|
|
|
|
imageData.curSrc = candidateSrc;
|
|
imageData.curCan = bestCandidate;
|
|
|
|
if ( candidateSrc !== curSrc ) {
|
|
pf.setSrc( img, bestCandidate );
|
|
}
|
|
pf.setSize( img );
|
|
}
|
|
};
|
|
|
|
pf.setSrc = function( img, bestCandidate ) {
|
|
var origWidth;
|
|
img.src = bestCandidate.url;
|
|
|
|
// although this is a specific Safari issue, we don't want to take too much different code paths
|
|
if ( bestCandidate.set.type === "image/svg+xml" ) {
|
|
origWidth = img.style.width;
|
|
img.style.width = (img.offsetWidth + 1) + "px";
|
|
|
|
// next line only should trigger a repaint
|
|
// if... is only done to trick dead code removal
|
|
if ( img.offsetWidth + 1 ) {
|
|
img.style.width = origWidth;
|
|
}
|
|
}
|
|
};
|
|
|
|
pf.getSet = function( img ) {
|
|
var i, set, supportsType;
|
|
var match = false;
|
|
var sets = img [ pf.ns ].sets;
|
|
|
|
for ( i = 0; i < sets.length && !match; i++ ) {
|
|
set = sets[i];
|
|
|
|
if ( !set.srcset || !pf.matchesMedia( set.media ) || !(supportsType = pf.supportsType( set.type )) ) {
|
|
continue;
|
|
}
|
|
|
|
if ( supportsType === "pending" ) {
|
|
set = supportsType;
|
|
}
|
|
|
|
match = set;
|
|
break;
|
|
}
|
|
|
|
return match;
|
|
};
|
|
|
|
pf.parseSets = function( element, parent, options ) {
|
|
var srcsetAttribute, imageSet, isWDescripor, srcsetParsed;
|
|
|
|
var hasPicture = parent && parent.nodeName.toUpperCase() === "PICTURE";
|
|
var imageData = element[ pf.ns ];
|
|
|
|
if ( imageData.src === undefined || options.src ) {
|
|
imageData.src = getImgAttr.call( element, "src" );
|
|
if ( imageData.src ) {
|
|
setImgAttr.call( element, srcAttr, imageData.src );
|
|
} else {
|
|
removeImgAttr.call( element, srcAttr );
|
|
}
|
|
}
|
|
|
|
if ( imageData.srcset === undefined || options.srcset || !pf.supSrcset || element.srcset ) {
|
|
srcsetAttribute = getImgAttr.call( element, "srcset" );
|
|
imageData.srcset = srcsetAttribute;
|
|
srcsetParsed = true;
|
|
}
|
|
|
|
imageData.sets = [];
|
|
|
|
if ( hasPicture ) {
|
|
imageData.pic = true;
|
|
getAllSourceElements( parent, imageData.sets );
|
|
}
|
|
|
|
if ( imageData.srcset ) {
|
|
imageSet = {
|
|
srcset: imageData.srcset,
|
|
sizes: getImgAttr.call( element, "sizes" )
|
|
};
|
|
|
|
imageData.sets.push( imageSet );
|
|
|
|
isWDescripor = (alwaysCheckWDescriptor || imageData.src) && regWDesc.test(imageData.srcset || "");
|
|
|
|
// add normal src as candidate, if source has no w descriptor
|
|
if ( !isWDescripor && imageData.src && !getCandidateForSrc(imageData.src, imageSet) && !imageSet.has1x ) {
|
|
imageSet.srcset += ", " + imageData.src;
|
|
imageSet.cands.push({
|
|
url: imageData.src,
|
|
d: 1,
|
|
set: imageSet
|
|
});
|
|
}
|
|
|
|
} else if ( imageData.src ) {
|
|
imageData.sets.push( {
|
|
srcset: imageData.src,
|
|
sizes: null
|
|
} );
|
|
}
|
|
|
|
imageData.curCan = null;
|
|
imageData.curSrc = undefined;
|
|
|
|
// if img has picture or the srcset was removed or has a srcset and does not support srcset at all
|
|
// or has a w descriptor (and does not support sizes) set support to false to evaluate
|
|
imageData.supported = !( hasPicture || ( imageSet && !pf.supSrcset ) || isWDescripor );
|
|
|
|
if ( srcsetParsed && pf.supSrcset && !imageData.supported ) {
|
|
if ( srcsetAttribute ) {
|
|
setImgAttr.call( element, srcsetAttr, srcsetAttribute );
|
|
element.srcset = "";
|
|
} else {
|
|
removeImgAttr.call( element, srcsetAttr );
|
|
}
|
|
}
|
|
|
|
if (imageData.supported && !imageData.srcset && ((!imageData.src && element.src) || element.src !== pf.makeUrl(imageData.src))) {
|
|
if (imageData.src === null) {
|
|
element.removeAttribute("src");
|
|
} else {
|
|
element.src = imageData.src;
|
|
}
|
|
}
|
|
|
|
imageData.parsed = true;
|
|
};
|
|
|
|
pf.fillImg = function(element, options) {
|
|
var imageData;
|
|
var extreme = options.reselect || options.reevaluate;
|
|
|
|
// expando for caching data on the img
|
|
if ( !element[ pf.ns ] ) {
|
|
element[ pf.ns ] = {};
|
|
}
|
|
|
|
imageData = element[ pf.ns ];
|
|
|
|
// if the element has already been evaluated, skip it
|
|
// unless `options.reevaluate` is set to true ( this, for example,
|
|
// is set to true when running `picturefill` on `resize` ).
|
|
if ( !extreme && imageData.evaled === evalId ) {
|
|
return;
|
|
}
|
|
|
|
if ( !imageData.parsed || options.reevaluate ) {
|
|
pf.parseSets( element, element.parentNode, options );
|
|
}
|
|
|
|
if ( !imageData.supported ) {
|
|
applyBestCandidate( element );
|
|
} else {
|
|
imageData.evaled = evalId;
|
|
}
|
|
};
|
|
|
|
pf.setupRun = function() {
|
|
if ( !alreadyRun || isVwDirty || (DPR !== window.devicePixelRatio) ) {
|
|
updateMetrics();
|
|
}
|
|
};
|
|
|
|
// If picture is supported, well, that's awesome.
|
|
if ( pf.supPicture ) {
|
|
picturefill = noop;
|
|
pf.fillImg = noop;
|
|
} else {
|
|
|
|
// Set up picture polyfill by polling the document
|
|
(function() {
|
|
var isDomReady;
|
|
var regReady = window.attachEvent ? /d$|^c/ : /d$|^c|^i/;
|
|
|
|
var run = function() {
|
|
var readyState = document.readyState || "";
|
|
|
|
timerId = setTimeout(run, readyState === "loading" ? 200 : 999);
|
|
if ( document.body ) {
|
|
pf.fillImgs();
|
|
isDomReady = isDomReady || regReady.test(readyState);
|
|
if ( isDomReady ) {
|
|
clearTimeout( timerId );
|
|
}
|
|
|
|
}
|
|
};
|
|
|
|
var timerId = setTimeout(run, document.body ? 9 : 99);
|
|
|
|
// Also attach picturefill on resize and readystatechange
|
|
// http://modernjavascript.blogspot.com/2013/08/building-better-debounce.html
|
|
var debounce = function(func, wait) {
|
|
var timeout, timestamp;
|
|
var later = function() {
|
|
var last = (new Date()) - timestamp;
|
|
|
|
if (last < wait) {
|
|
timeout = setTimeout(later, wait - last);
|
|
} else {
|
|
timeout = null;
|
|
func();
|
|
}
|
|
};
|
|
|
|
return function() {
|
|
timestamp = new Date();
|
|
|
|
if (!timeout) {
|
|
timeout = setTimeout(later, wait);
|
|
}
|
|
};
|
|
};
|
|
var lastClientWidth = docElem.clientHeight;
|
|
var onResize = function() {
|
|
isVwDirty = Math.max(window.innerWidth || 0, docElem.clientWidth) !== units.width || docElem.clientHeight !== lastClientWidth;
|
|
lastClientWidth = docElem.clientHeight;
|
|
if ( isVwDirty ) {
|
|
pf.fillImgs();
|
|
}
|
|
};
|
|
|
|
on( window, "resize", debounce(onResize, 99 ) );
|
|
on( document, "readystatechange", run );
|
|
})();
|
|
}
|
|
|
|
pf.picturefill = picturefill;
|
|
//use this internally for easy monkey patching/performance testing
|
|
pf.fillImgs = picturefill;
|
|
pf.teardownRun = noop;
|
|
|
|
/* expose methods for testing */
|
|
picturefill._ = pf;
|
|
|
|
window.picturefillCFG = {
|
|
pf: pf,
|
|
push: function(args) {
|
|
var name = args.shift();
|
|
if (typeof pf[name] === "function") {
|
|
pf[name].apply(pf, args);
|
|
} else {
|
|
cfg[name] = args[0];
|
|
if (alreadyRun) {
|
|
pf.fillImgs( { reselect: true } );
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
while (setOptions && setOptions.length) {
|
|
window.picturefillCFG.push(setOptions.shift());
|
|
}
|
|
|
|
/* expose picturefill */
|
|
window.picturefill = picturefill;
|
|
|
|
/* expose picturefill */
|
|
if ( typeof module === "object" && typeof module.exports === "object" ) {
|
|
// CommonJS, just export
|
|
module.exports = picturefill;
|
|
} else if ( typeof define === "function" && define.amd ) {
|
|
// AMD support
|
|
define( "picturefill", function() { return picturefill; } );
|
|
}
|
|
|
|
// IE8 evals this sync, so it must be the last thing we do
|
|
if ( !pf.supPicture ) {
|
|
types[ "image/webp" ] = detectTypeSupport("image/webp", "data:image/webp;base64,UklGRkoAAABXRUJQVlA4WAoAAAAQAAAAAAAAAAAAQUxQSAwAAAABBxAR/Q9ERP8DAABWUDggGAAAADABAJ0BKgEAAQADADQlpAADcAD++/1QAA==" );
|
|
}
|
|
|
|
} )( window, document );
|