lazysizes
Version:
High performance (jankfree) lazy loader for images (including responsive images), iframes and scripts (widgets).
2 lines • 3.79 kB
JavaScript
/*! lazysizes - v4.0.1 */
!function(a,b){var c=function(){b(a.lazySizes),a.removeEventListener("lazyunveilread",c,!0)};b=b.bind(null,a,a.document),"object"==typeof module&&module.exports?b(require("lazysizes"),require("../fix-ios-sizes/fix-ios-sizes")):a.lazySizes?c():a.addEventListener("lazyunveilread",c,!0)}(window,function(a,b,c){"use strict";var d,e=c&&c.cfg||a.lazySizesConfig,f=b.createElement("img"),g="sizes"in f&&"srcset"in f,h=/\s+\d+h/g,i=function(){var a=/\s+(\d+)(w|h)\s+(\d+)(w|h)/,c=Array.prototype.forEach;return function(d){var e=b.createElement("img"),f=function(b){var c,d=b.getAttribute(lazySizesConfig.srcsetAttr);d&&(d.match(a)&&(c="w"==RegExp.$2?RegExp.$1/RegExp.$3:RegExp.$3/RegExp.$1,c&&b.setAttribute("data-aspectratio",c)),b.setAttribute(lazySizesConfig.srcsetAttr,d.replace(h,"")))},g=function(a){var b=a.target.parentNode;b&&"PICTURE"==b.nodeName&&c.call(b.getElementsByTagName("source"),f),f(a.target)},i=function(){e.currentSrc&&b.removeEventListener("lazybeforeunveil",g)};d[1]&&(b.addEventListener("lazybeforeunveil",g),e.onload=i,e.onerror=i,e.srcset="data:,a 1w 1h",e.complete&&i())}}();if(e||(e={},a.lazySizesConfig=e),e.supportsType||(e.supportsType=function(a){return!a}),!a.picturefill&&!e.pf){if(a.HTMLPictureElement&&g)return b.msElementsFromPoint&&i(navigator.userAgent.match(/Edge\/(\d+)/)),void(e.pf=function(){});e.pf=function(b){var c,e;if(!a.picturefill)for(c=0,e=b.elements.length;e>c;c++)d(b.elements[c])},d=function(){var f=function(a,b){return a.w-b.w},i=/^\s*\d+\.*\d*px\s*$/,j=function(a){var b,c,d=a.length,e=a[d-1],f=0;for(f;d>f;f++)if(e=a[f],e.d=e.w/a.w,e.d>=a.d){!e.cached&&(b=a[f-1])&&b.d>a.d-.13*Math.pow(a.d,2.2)&&(c=Math.pow(b.d-.6,1.6),b.cached&&(b.d+=.15*c),b.d+(e.d-a.d)*c>a.d&&(e=b));break}return e},k=function(){var a,b=/(([^,\s].[^\s]+)\s+(\d+)w)/g,c=/\s/,d=function(b,c,d,e){a.push({c:c,u:d,w:1*e})};return function(e){return a=[],e=e.trim(),e.replace(h,"").replace(b,d),a.length||!e||c.test(e)||a.push({c:e,u:e,w:99}),a}}(),l=function(){l.init||(l.init=!0,addEventListener("resize",function(){var a,c=b.getElementsByClassName("lazymatchmedia"),e=function(){var a,b;for(a=0,b=c.length;b>a;a++)d(c[a])};return function(){clearTimeout(a),a=setTimeout(e,66)}}()))},m=function(b,d){var f,g=b.getAttribute("srcset")||b.getAttribute(e.srcsetAttr);!g&&d&&(g=b._lazypolyfill?b._lazypolyfill._set:b.getAttribute(e.srcAttr)||b.getAttribute("src")),b._lazypolyfill&&b._lazypolyfill._set==g||(f=k(g||""),d&&b.parentNode&&(f.isPicture="PICTURE"==b.parentNode.nodeName.toUpperCase(),f.isPicture&&a.matchMedia&&(c.aC(b,"lazymatchmedia"),l())),f._set=g,Object.defineProperty(b,"_lazypolyfill",{value:f,writable:!0}))},n=function(b){var d=a.devicePixelRatio||1,e=c.getX&&c.getX(b);return Math.min(e||d,2.5,d)},o=function(b){return a.matchMedia?(o=function(a){return!a||(matchMedia(a)||{}).matches})(b):!b},p=function(a){var b,d,g,h,k,l,p;if(h=a,m(h,!0),k=h._lazypolyfill,k.isPicture)for(d=0,b=a.parentNode.getElementsByTagName("source"),g=b.length;g>d;d++)if(e.supportsType(b[d].getAttribute("type"),a)&&o(b[d].getAttribute("media"))){h=b[d],m(h),k=h._lazypolyfill;break}return k.length>1?(p=h.getAttribute("sizes")||"",p=i.test(p)&&parseInt(p,10)||c.gW(a,a.parentNode),k.d=n(a),!k.src||!k.w||k.w<p?(k.w=p,l=j(k.sort(f)),k.src=l):l=k.src):l=k[0],l},q=function(a){if(!g||!a.parentNode||"PICTURE"==a.parentNode.nodeName.toUpperCase()){var b=p(a);b&&b.u&&a._lazypolyfill.cur!=b.u&&(a._lazypolyfill.cur=b.u,b.cached=!0,a.setAttribute(e.srcAttr,b.u),a.setAttribute("src",b.u))}};return q.parse=k,q}(),e.loadedClass&&e.loadingClass&&!function(){var a=[];['img[sizes$="px"][srcset].',"picture > img:not([srcset])."].forEach(function(b){a.push(b+e.loadedClass),a.push(b+e.loadingClass)}),e.pf({elements:b.querySelectorAll(a.join(", "))})}()}});