①image-set
.cnt{
background-image: url(../img/x.png);
background: -webkit-image-set(
url(../img/1x.png) 1x,
url(../img/2x.png) 2X,
url(.../img/3X.png) 3X;
);
}
② word-break: break-all; 单词折断换行
word-wrap: break-word; 整个单词换行
③计算图片加载时间
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>img-load</title>
</head>
<body>
<img src="https://www.baidu.com/img/bd_logo1.png">
<script type="text/javascript">
var measure_start = performance.now();
document.getElementsByTagName("img")[0].addEventListener("load", function(){
var measure_end = performance.now();
console.log("image load time:" + (measure_end - measure_start));
},false);
</script>
</body>
</html>
④scrollbar