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respimage.dev.js
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respimage.dev.js
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/*! Respimg - Responsive Images that work today.
* Author: Alexander Farkas, 2014
* Author: Scott Jehl, Filament Group, 2012 ( new proposal implemented by Shawn Jansepar )
* License: MIT
* Spec: http://picture.responsiveimages.org/
*/
(function( window, document, undefined ) {
// Enable strict mode
"use strict";
if ( typeof RIDEBUG == "undefined" ) {
window.RIDEBUG = true;
}
var lowTreshHold, partialLowTreshHold, isLandscape, lazyFactor, tMemory, substractCurRes, warn, eminpx,
alwaysCheckWDescriptor, resizeThrottle, evalID;
// local object for method references and testing exposure
var ri = {};
var noop = function() {};
var image = document.createElement( "img" );
var getImgAttr = image.getAttribute;
var setImgAttr = image.setAttribute;
var removeImgAttr = image.removeAttribute;
var docElem = document.documentElement;
var types = {};
var cfg = {
//resource selection:
xQuant: 1,
lazyFactor: 0.4,
maxX: 2
};
var srcAttr = "data-pfsrc";
var srcsetAttr = srcAttr + "set";
var reflowBug = "webkitBackfaceVisibility" in docElem.style;
var ua = navigator.userAgent;
var supportAbort = (/rident/).test(ua) || ((/ecko/).test(ua) && ua.match(/rv\:(\d+)/) && RegExp.$1 > 35 );
var curSrcProp = "currentSrc";
var regWDesc = /\s+\+?\d+(e\d+)?w/;
var regSize = /((?:\([^)]+\)(?:\s*and\s*|\s*or\s*|\s*not\s*)?)+)?\s*(.+)/;
var regDescriptor = /^([\+eE\d\.]+)(w|x)$/; // currently no h
var regHDesc = /\s*\d+h\s*/;
var setOptions = window.respimgCFG;
/**
* Shortcut property for https://w3c.github.io/webappsec/specs/mixedcontent/#restricts-mixed-content ( for easy overriding in tests )
*/
var isSSL = location.protocol == "https:";
// baseStyle also used by getEmValue (i.e.: width: 1em is important)
var baseStyle = "position:absolute;left:0;visibility:hidden;display:block;padding:0;border:none;font-size:1em;width:1em;overflow:hidden;clip:rect(0px, 0px, 0px, 0px)";
var fsCss = "font-size:100%!important;";
var isVwDirty = true;
var cssCache = {};
var sizeLengthCache = {};
var DPR = window.devicePixelRatio;
var units = {
px: 1,
'in': 96
};
var anchor = document.createElement( "a" );
/**
* alreadyRun flag used for setOptions. is it true setOptions will reevaluate
* @type {boolean}
*/
var alreadyRun = false;
var on = function(obj, evt, fn, capture) {
if ( obj.addEventListener ) {
obj.addEventListener(evt, fn, capture || false);
} else if ( obj.attachEvent ) {
obj.attachEvent( "on"+ evt, fn);
}
};
var off = function(obj, evt, fn, capture) {
if ( obj.removeEventListener ) {
obj.removeEventListener(evt, fn, capture || false);
} else if ( obj.detachEvent ) {
obj.detachEvent( "on"+ evt, fn);
}
};
/**
* simple memoize function:
*/
var memoize = function(fn) {
var cache = {};
return function(input) {
if ( !(input in cache) ) {
cache[ input ] = fn(input);
}
return cache[ input ];
};
};
/**
* gets a mediaquery and returns a boolean or gets a css length and returns a number
* @param css mediaqueries or css length
* @returns {boolean|number}
*
* based on: https://gist.github.com/jonathantneal/db4f77009b155f083738
*/
var evalCSS = (function(){
var regLength = /^([\d\.]+)(em|vw|px)$/;
var replace = function() {
var args = arguments, index = 0, string = args[0];
while (++index in args) {
string = string.replace(args[index], args[++index]);
}
return string;
};
var buidlStr = memoize(function(css) {
return "return " + replace((css || "").toLowerCase(),
// interpret `and`
/\band\b/g, "&&",
// interpret `,`
/,/g, "||",
// interpret `min-` as >=
/min-([a-z-\s]+):/g, "e.$1>=",
// interpret `min-` as <=
/max-([a-z-\s]+):/g, "e.$1<=",
//calc value
/calc([^)]+)/g, "($1)",
// interpret css values
/(\d+[\.]*[\d]*)([a-z]+)/g, "($1 * e.$2)",
//make eval less evil
/^(?!(e.[a-z]|[0-9\.&=|><\+\-\*\(\)\/])).*/ig, ""
);
});
return function(css, length) {
var parsedLength;
if (!(css in cssCache)) {
cssCache[css] = false;
if(length && (parsedLength = css.match( regLength ))){
cssCache[css] = parsedLength[ 1 ] * units[parsedLength[ 2 ]];
} else {
/*jshint evil:true */
try{
cssCache[css] = new Function("e", buidlStr(css))(units);
} catch(e){}
/*jshint evil:false */
}
}
return cssCache[css];
};
})();
var setResolution = function ( candidate, sizesattr ) {
if ( candidate.w ) { // h = means height: || descriptor.type == 'h' do not handle yet...
candidate.cWidth = ri.calcListLength( sizesattr || "100vw" );
candidate.res = candidate.w / candidate.cWidth ;
} else {
candidate.res = candidate.x;
}
return candidate;
};
/**
*
* @param opt
*/
var respimage = function( opt ) {
var elements, i, plen;
var options = opt || {};
if ( options.elements && options.elements.nodeType == 1 ) {
if ( options.elements.nodeName.toUpperCase() == "IMG" ) {
options.elements = [ options.elements ];
} else {
options.context = options.elements;
options.elements = null;
}
}
if(options.reparse){
options.reevaluate = true;
if(window.console && console.warn){
console.warn('reparse was renamed to reevaluate!');
}
}
elements = options.elements || ri.qsa( (options.context || document), ( options.reevaluate || options.reselect ) ? ri.sel : ri.selShort );
if ( (plen = elements.length) ) {
ri.setupRun( options );
alreadyRun = true;
// Loop through all elements
for ( i = 0; i < plen; i++ ) {
ri.fillImg(elements[ i ], options);
}
ri.teardownRun( options );
}
};
var parseDescriptor = memoize(function ( descriptor ) {
var descriptorObj = [1, 'x'];
var parsedDescriptor = trim( descriptor || "" );
if ( parsedDescriptor ) {
parsedDescriptor = parsedDescriptor.replace(regHDesc, "");
if ( ( parsedDescriptor ).match( regDescriptor ) ) {
descriptorObj = [RegExp.$1 * 1, RegExp.$2];
if ( RIDEBUG && (
descriptorObj[0] < 0 ||
isNaN( descriptorObj[0] ) ||
(descriptorObj[1] == "w" && /\./.test(''+descriptorObj[0]))
) ) {
warn( "bad descriptor: " + descriptor );
}
} else {
descriptorObj = false;
if ( RIDEBUG ) {
warn( "unknown descriptor: " + descriptor );
}
}
}
return descriptorObj;
});
/**
* outputs a warning for the developer
* @param {message}
* @type {Function}
*/
if(RIDEBUG){
warn = ( window.console && console.warn ) ?
function( message ) {
console.warn( message );
} :
noop
;
}
if( !(curSrcProp in image) ){
curSrcProp = "src";
}
// Add support for standard mime types.
types["image/jpeg"] = true;
types["image/gif"] = true;
types["image/png"] = true;
// test svg support
types[ "image/svg+xml" ] = document.implementation.hasFeature( "http://wwwindow.w3.org/TR/SVG11/feature#Image", "1.1" );
/**
* a trim workaroung mainly for IE8
* @param str
* @returns {string}
*/
function trim( str ) {
return str.trim ? str.trim() : str.replace( /^\s+|\s+$/g, "" );
}
/**
* updates the internal vW property with the current viewport width in px
*/
function updateMetrics() {
var dprM;
isVwDirty = false;
DPR = window.devicePixelRatio;
cssCache = {};
sizeLengthCache = {};
dprM = (DPR || 1) * cfg.xQuant;
if(!cfg.uT){
cfg.maxX = Math.max(1.3, cfg.maxX);
dprM = Math.min( dprM, cfg.maxX );
ri.DPR = dprM;
}
units.width = Math.max(window.innerWidth || 0, docElem.clientWidth);
units.height = Math.max(window.innerHeight || 0, docElem.clientHeight);
units.vw = units.width / 100;
units.vh = units.height / 100;
units.em = ri.getEmValue();
units.rem = units.em;
lazyFactor = cfg.lazyFactor / 2;
lazyFactor = (lazyFactor * dprM) + lazyFactor;
substractCurRes = 0.4 + (0.1 * dprM);
lowTreshHold = 0.5 + (0.2 * dprM);
partialLowTreshHold = 0.5 + (0.25 * dprM);
tMemory = dprM + 1.3;
if(!(isLandscape = units.width > units.height)){
lazyFactor *= 0.9;
}
if(supportAbort){
lazyFactor *= 0.9;
}
evalID = [units.width, units.height, dprM].join('-');
}
function chooseLowRes( lowRes, diff, dpr ) {
var add = diff * Math.pow(lowRes - 0.4, 1.9);
if(!isLandscape){
add /= 1.3;
}
lowRes += add;
return lowRes > dpr;
}
function applyBestCandidate( img ) {
var srcSetCandidates;
var matchingSet = ri.getSet( img );
var evaluated = false;
if ( matchingSet != "pending" ) {
evaluated = evalID;
if ( matchingSet ) {
srcSetCandidates = ri.setRes( matchingSet );
evaluated = ri.applySetCandidate( srcSetCandidates, img );
}
}
img[ ri.ns ].evaled = evaluated;
}
function ascendingSort( a, b ) {
return a.res - b.res;
}
function setSrcToCur( img, src, set ) {
var candidate;
if ( !set && src ) {
set = img[ ri.ns ].sets;
set = set && set[set.length - 1];
}
candidate = getCandidateForSrc(src, set);
if ( candidate ) {
src = ri.makeUrl(src);
img[ ri.ns ].curSrc = src;
img[ ri.ns ].curCan = candidate;
if ( !candidate.res ) {
setResolution( candidate, candidate.set.sizes );
}
}
return candidate;
}
function getCandidateForSrc( src, set ) {
var i, candidate, candidates;
if ( src && set ) {
candidates = ri.parseSet( set );
src = ri.makeUrl(src);
for ( i = 0; i < candidates.length; i++ ) {
if ( src == ri.makeUrl(candidates[ i ].url) ) {
candidate = candidates[ i ];
break;
}
}
}
return candidate;
}
function getAllSourceElements( picture, candidates ) {
var i, len, source, srcset;
// SPEC mismatch intended for size and perf:
// actually only source elements preceding the img should be used
// also note: don't use qsa here, because IE8 sometimes doesn't like source as the key part in a selector
var sources = picture.getElementsByTagName( "source" );
for ( i = 0, len = sources.length; i < len; i++ ) {
source = sources[ i ];
source[ ri.ns ] = true;
srcset = source.getAttribute( "srcset" );
if ( RIDEBUG && document.documentMode != 9 && source.parentNode != picture ) {
warn( "all source elements have to be a child of the picture element. For IE9 support wrap them in an audio/video element, BUT with conditional comments" );
}
// if source does not have a srcset attribute, skip
if ( srcset ) {
candidates.push( {
srcset: srcset,
media: source.getAttribute( "media" ),
type: source.getAttribute( "type" ),
sizes: source.getAttribute( "sizes" )
} );
}
if ( RIDEBUG && source.getAttribute( "src" ) ) {
warn( "`src` on `source` invalid, use `srcset`." );
}
}
if ( RIDEBUG ) {
var srcTest = ri.qsa( picture, "source, img");
if ( srcTest[ srcTest.length - 1].nodeName.toUpperCase() == "SOURCE" ) {
warn( "all sources inside picture have to precede the img element" );
}
}
}
// namespace
ri.ns = ("ri" + new Date().getTime()).substr(0, 9);
// srcset support test
ri.supSrcset = "srcset" in image;
ri.supSizes = "sizes" in image;
ri.supPicture = !!window.HTMLPictureElement;
if (ri.supSrcset && ri.supPicture && !ri.supSizes) {
(function(image2) {
image.srcset = "data:,a";
image2.src = "data:,a";
ri.supSrcset = image.complete === image2.complete;
ri.supPicture = ri.supSrcset && ri.supPicture;
})(document.createElement("img"));
}
// using ri.qsa instead of dom traversing does scale much better,
// especially on sites mixing responsive and non-responsive images
ri.selShort = "picture>img,img[srcset]";
ri.sel = ri.selShort;
ri.cfg = cfg;
if ( ri.supSrcset ) {
ri.sel += ",img[" + srcsetAttr + "]";
}
/**
* Shortcut property for `devicePixelRatio` ( for easy overriding in tests )
*/
ri.DPR = (DPR || 1 );
ri.u = units;
// container of supported mime types that one might need to qualify before using
ri.types = types;
alwaysCheckWDescriptor = ri.supSrcset && !ri.supSizes;
ri.setSize = noop;
/**
* Gets a string and returns the absolute URL
* @param src
* @returns {String} absolute URL
*/
ri.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}
*/
ri.qsa = function(context, sel) {
return context.querySelectorAll(sel);
};
/**
* Shortcut method for matchMedia ( for easy overriding in tests )
* wether native or ri.mMQ is used will be decided lazy on first call
* @returns {boolean}
*/
ri.matchesMedia = function() {
if ( window.matchMedia && (matchMedia( "(min-width: 0.1em)" ) || {}).matches ) {
ri.matchesMedia = function( media ) {
return !media || ( matchMedia( media ).matches );
};
} else {
ri.matchesMedia = ri.mMQ;
}
return ri.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}
*/
ri.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}
*/
ri.calcLength = function( sourceSizeValue ) {
var value = evalCSS(sourceSizeValue, true) || false;
if(value < 0){
value = false;
}
if ( RIDEBUG && (value === false || value < 0) ) {
warn( "invalid source size: " + sourceSizeValue );
}
return value;
};
/**
* Takes a type string and checks if its supported
*/
ri.supportsType = function( type ) {
return ( type ) ? types[ type ] : true;
};
/**
* Parses a sourceSize into mediaCondition (media) and sourceSizeValue (length)
* @param sourceSizeStr
* @returns {*}
*/
ri.parseSize = memoize(function( sourceSizeStr ) {
var match = ( sourceSizeStr || "" ).match(regSize);
return {
media: match && match[1],
length: match && match[2]
};
});
ri.parseSet = function( set ) {
/*
* A lot of this was pulled from Boris Smus’ parser for the now-defunct WHATWG `srcset`
* https://github.com/borismus/srcset-polyfill/blob/master/js/srcset-info.js
*
* 1. Let input (`srcset`) be the value passed to this algorithm.
* 2. Let position be a pointer into input, initially pointing at the start of the string.
* 3. Let raw candidates be an initially empty ordered list of URLs with associated
* unparsed descriptors. The order of entries in the list is the order in which entries
* are added to the list.
*/
if ( !set.cands ) {
var pos, url, descriptor, last, descpos, can, firstDescriptorType;
var srcset = set.srcset;
set.cands = [];
while ( srcset ) {
srcset = srcset.replace(/^\s+/g,"");
// 5. Collect a sequence of characters that are not space characters, and let that be url.
pos = srcset.search(/\s/g);
descriptor = null;
if ( pos != -1 ) {
url = srcset.slice( 0, pos );
last = url.charAt( url.length - 1 );
// 6. If url ends with a U+002C COMMA character (,), remove that character from url
// and let descriptors be the empty string. Otherwise, follow these substeps
// 6.1. If url is empty, then jump to the step labeled descriptor parser.
if ( last == "," || !url ) {
url = url.replace(/,+$/, "");
descriptor = "";
}
srcset = srcset.slice( pos + 1 );
// 6.2. Collect a sequence of characters that are not U+002C COMMA characters (,), and
// let that be descriptors.
if ( descriptor == null ) {
descpos = srcset.indexOf( "," );
if ( descpos != -1 ) {
descriptor = srcset.slice( 0, descpos );
srcset = srcset.slice( descpos + 1 );
} else {
descriptor = srcset;
srcset = "";
}
}
} else {
url = srcset;
srcset = "";
}
// 7. Add url to raw candidates, associated with descriptors.
if ( url && (descriptor = parseDescriptor( descriptor )) ) {
if ( RIDEBUG ) {
if ( !firstDescriptorType ) {
firstDescriptorType = set.sizes ? "w" : descriptor[1];
}
if ( firstDescriptorType != descriptor[1] ) {
warn("mixing x with a w descriptor/sizes attribute in one srcset doesn't make sense in most cases and is invalid.");
}
}
can = {
url: url.replace(/^,+/, ""),
set: set
};
can[descriptor[1]] = descriptor[0];
if(descriptor[1] == 'x' && descriptor[0] == 1){
set.has1x = true;
}
set.cands.push(can);
}
}
}
return set.cands;
};
/**
* returns 1em in css px for html/body default size
* function taken from respondjs
* @returns {*|number}
*/
ri.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
*/
ri.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 sourceSize, parsedSize, length, media, i, len;
var sourceSizeList = trim( sourceSizeListStr ).split( /\s*,\s*/ );
var winningLength = false;
for ( i = 0, len = sourceSizeList.length; i < len; i++ ) {
// Match <media-condition>? length, ie ( min-width: 50em ) 100%
sourceSize = sourceSizeList[ i ];
// Split "( min-width: 50em ) 100%" into separate strings
parsedSize = ri.parseSize( sourceSize );
length = parsedSize.length;
media = parsedSize.media;
if ( !length ) {
continue;
}
// if there is no media query or it matches, choose this as our winning length
// and end algorithm
if ( ri.matchesMedia( media ) && (winningLength = ri.calcLength( length )) !== false ) {
break;
}
}
// pass the length to a method that can properly determine length
// in pixels based on these formats: http://dev.w3.org/csswg/css-values-3/#length-value
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
*/
ri.setRes = function( set ) {
var candidates;
if ( set ) {
candidates = ri.parseSet( set );
for ( var i = 0, len = candidates.length; i < len; i++ ) {
setResolution( candidates[ i ], set.sizes );
}
}
return candidates;
};
ri.setRes.res = setResolution;
ri.applySetCandidate = function( candidates, img ) {
if ( !candidates.length ) {return;}
var candidate,
dpr,
i,
j,
diff,
length,
bestCandidate,
curSrc,
curCan,
isSameSet,
candidateSrc,
abortCurSrc,
oldRes;
var imageData = img[ ri.ns ];
var evaled = evalID;
var lazyF = lazyFactor;
var sub = substractCurRes;
curSrc = imageData.curSrc || img[curSrcProp];
curCan = imageData.curCan || setSrcToCur(img, curSrc, candidates[0].set);
dpr = ri.DPR;
oldRes = curCan && curCan.res;
//if we have a current source, we might either become lazy or give this source some advantage
if ( !bestCandidate && curSrc ) {
abortCurSrc = (supportAbort && !img.complete && curCan && oldRes - 0.2 > dpr);
if( !abortCurSrc && (!curCan || tMemory > oldRes) ){
//add some lazy padding to the src
if ( curCan && oldRes < dpr && oldRes > lowTreshHold ) {
if(oldRes < partialLowTreshHold){
lazyF *= 0.8;
sub += (0.04 * dpr);
}
curCan.res += lazyF * Math.pow(oldRes - sub, 2);
}
isSameSet = !imageData.pic || (curCan && curCan.set == candidates[ 0 ].set);
if ( curCan && isSameSet && curCan.res >= dpr ) {
bestCandidate = curCan;
}
}
}
if ( !bestCandidate ) {
if ( oldRes ) {
curCan.res = curCan.res - ((curCan.res - oldRes) / 2);
}
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 ] &&
(diff = (candidate.res - dpr)) &&
(abortCurSrc || curSrc != ri.makeUrl( candidate.url )) &&
chooseLowRes(candidates[ j ].res, diff, dpr)) {
bestCandidate = candidates[ j ];
} else {
bestCandidate = candidate;
}
break;
}
}
}
if ( oldRes ) {
curCan.res = oldRes;
}
if ( bestCandidate ) {
candidateSrc = ri.makeUrl( bestCandidate.url );
imageData.curSrc = candidateSrc;
imageData.curCan = bestCandidate;
if ( candidateSrc != curSrc ) {
ri.setSrc( img, bestCandidate );
if ( RIDEBUG ) {
testImgDimensions(img, bestCandidate);
if(isSSL && !bestCandidate.url.indexOf( "http:" )){
warn( "insecure: " + candidateSrc );
}
}
}
ri.setSize( img );
}
return evaled;
};
ri.setSrc = function( img, bestCandidate ) {
var origStyle;
img.src = bestCandidate.url;
if ( reflowBug ) {
origStyle = img.style.zoom;
img.style.zoom = "0.999";
// next line only should trigger a repaint
// if... is only done to trick dead code removal
if ( img.offsetWidth || 1 ) {
img.style.zoom = origStyle;
}
}
};
ri.getSet = function( img ) {
var i, set, supportsType;
var match = false;
var sets = img [ ri.ns ].sets;
for ( i = 0; i < sets.length && !match; i++ ) {
set = sets[i];
if ( !set.srcset || !ri.matchesMedia( set.media ) || !(supportsType = ri.supportsType( set.type )) ) {
continue;
}
if ( supportsType == "pending" ) {
set = supportsType;
}
match = set;
break;
}
return match;
};
ri.parseSets = function( element, parent, options ) {
var srcsetAttribute, imageSet, isWDescripor, srcsetParsed;
var hasPicture = parent.nodeName.toUpperCase() == "PICTURE";
var imageData = element[ ri.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 || !ri.supSrcset || element.srcset || options.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,
x: 1,
set: imageSet
});
}
if ( RIDEBUG && !hasPicture && isWDescripor && imageData.src && imageSet.srcset.indexOf(element[ ri.ns ].src) == -1 ) {
warn("The fallback candidate (`src`) isn't described inside the srcset attribute. Normally you want to describe all available candidates.");
}
} 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 && !ri.supSrcset ) || isWDescripor );
if ( srcsetParsed && ri.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 != ri.makeUrl(imageData.src))){
if(imageData.src == null){
element.removeAttribute('src');
} else {
element.src = imageData.src;
}
}
if ( RIDEBUG ) {
testMediaOrder(imageData.sets, 'source');
}
imageData.parsed = true;
};
ri.fillImg = function(element, options) {
var parent, imageData;
var extreme = options.reselect || options.reevaluate;
// expando for caching data on the img
if ( !element[ ri.ns ] ) {
element[ ri.ns ] = {};
}
imageData = element[ ri.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 `respimage` on `resize` ).
if ( !extreme && imageData.evaled == evalID ) {
return;
}
if ( !imageData.parsed || options.reevaluate ) {
parent = element.parentNode;
if ( !parent ) {
return;
}