仍是前端圖片的老話題,花了半天時間,東拼西湊,湊出個demo,優勢在於代碼少,核心代碼就6行,目前剛作了旋轉,縮放,裁剪,濾鏡要js作,網絡上也有現成的代碼,javascript
可是想作到自定義的濾鏡咋辦呢?這還要從底層瞭解濾鏡的實現才行~實際上,咱們不管用C++,仍是java實現了濾鏡,都能移植到js端,原理是相通的。css
總之,再次強調,原理很重要,掌握了原理,你就能夠任性了。html
能夠放到http://runjs.cn/裏作驗證,好棒的在線工具~前端
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>js+css3</title>
</head>
<style type="text/css">
.clipzone
{
position:relative;
width:400px;
height:400px;
overflow:hidden;
}
.clipped
{
position:absolute;
}
</style>
<body>
<input type="button" value="rotate" onclick="rotate(20);"/>
<input type="button" value="scale" onclick="scale(1.5);"/>
<input type="button" value="clip" onclick="clip();"/>
<input type="button" value="support_canvas_test" onclick="support_canvas_test();"/>
<div class="clipzone" id="testdiv">
<img class="clipped" id="image1" src="http://www.artup.com/img/icon35.png" width="282" height="220" >
</div>
<script type="text/javascript">
var totalrotate = 0;
var totalscale = 0;
function rotate(sum){
totalrotate = totalrotate + sum;
var obj=document.getElementById("image1");
obj.style.webkitTransform="rotate("+totalrotate+"deg)";
}
function scale(sum){
totalscale = totalscale + sum;
var obj=document.getElementById("image1");
obj.style.webkitTransform="scale("+totalscale+")";
}
function clip(){
var obj=document.getElementById("image1");
obj.style.clip = "rect(20px, auto, auto, 10px)";
}
function support_canvas_test(){
var elem = document.createElement('canvas');
var context = elem.getContext('2d');
alert(typeof context.fillText === 'function'?"support":"not support");
}
var support_css3 = (function() {
var div = document.createElement('div'),
vendors = 'ms o moz webkit'.split(' '),
len = vendors.length;
return function(prop) {
if ( prop in div.style ) return true;
len = vendors.length;
while(len--) {
if ( vendors[len] + prop in div.style ) {
return true;
}
}
return false;
};
})();
</script>
</body>
</html>java