SVG实现描边动画
说起SVG,我是恨它又爱它,恨它是因为刚开始接触的时候自己傻B地想用代码去写它,其实在web上我们用它做交互也只是用了几个常用的特性而已,其他的标签知道这么一回事就成了,其实说白了它就是一种图片格式,你得去画它,网站上最长用的SVG交互效果就是描边动画了,今天就来实现它
先上效果图:
思路:要实现这种动画,我们要使用的是SVG的路径path标签,其中然后配合两个属性:stroke-dasharray和stroke-dashoffset,至于用什么方式实现动画效果就八仙过海了,我这里使用的是css3的animation
第一步:了解SVG的path
中文的意思就是路径,描边动画嘛,你得先给个路线我才能描边啊,路径就是这个路线:
先上网找个图片,放进AI里面,然后用钢笔勾勒路径,再把图片删掉,剩下路径,把它另存为svg,然后把它拖进编译器里,就能看到一堆代码,我们只要保留其中的path就好(不会用AI的给你个理由去勾搭设计师美眉)
第二步:了解stroke-dasharray和stroke-dashoffset
理解字面意思就好:
stroke-dasharray:就是把线条断开为虚线,下图就是我把stroke-dasharray设置为10的效果,它就变成虚线了,数值越大,线就越长
stroke-dashoffset:就是设置线条的偏移,设置了这个值后,线段就会偏移相应的值,我们要实现动画只要动态改变这个偏移值就好,那样线条就会动起来了
第三步:利用@keyframes实现动态描边
@keyframes describe{ from{ stroke-dashoffset: 1000; opacity: 1; } to{ stroke-dashoffset: 0; opacity: 0; } }
额~~有点快,没关系,明白意思就好,最后,描边完成之后再插入一个动画,让背景图片淡入,最终效果如下:
下班了,不调了,如果再慢点效果估计更好
上终板代码(直接拷贝就能跑):
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>super</title> 6 <script src="vivus.js"></script> 7 <style> 8 .super_logo{ 9 position: absolute; 10 opacity: 0; 11 animation:fadeIn 1s ease-in forwards; 12 -webkit-animation:fadeIn 1s ease-in forwards; 13 } 14 #super{ 15 position: absolute; 16 z-index: 1; 17 stroke-dasharray: 800; 18 stroke-dashoffset: 1000; 19 animation: describe 2s forwards; 20 -webkit-animation: describe 2s forwards; 21 } 22 @keyframes fadeIn{ 23 from{opacity: 0;} 24 80%{opacity: 0.5;} 25 to{opacity: 1;} 26 } 27 @-webkit-keyframes fadeIn{ 28 from{opacity: 0;} 29 80%{opacity: 0.5;} 30 to{opacity: 1;} 31 } 32 @keyframes describe{ 33 from{ 34 stroke-dashoffset: 1000; 35 opacity: 1; 36 } 37 to{ 38 stroke-dashoffset: 0; 39 opacity: 0; 40 } 41 } 42 @-webkit-keyframes describe{ 43 from{ 44 stroke-dashoffset: 1000; 45 opacity: 1; 46 } 47 to{ 48 stroke-dashoffset: 0; 49 opacity: 0; 50 } 51 } 52 </style> 53 </head> 54 <body style="background:#0f1a3a;"> 55 <img src="http://images2015.cnblogs.com/blog/754767/201606/754767-20160606165217980-1558570494.gif" alt="super" class="super_logo"> 56 <svg id="super" x="0px" y="0px" width="293px" height="200px" viewBox="0 0 293 200"> 57 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M67.667,39.667c0,0-33.334,17.333-46.667,36.667 58 c0,0,33.007,40.458,43.331,50.018c19.419,17.982,65.002,55.316,82.169,59.982c0,0,27.834-11.334,49.834-30.667S249,113,261,100 59 s9.334-12.333,15.334-22.333c0,0-21.333-29.333-44-38c0,0-162.001-5.334-163.334-2.667"/> 60 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M169.667,50.333c0,0-71.334-2.667-74.667,8.667s42,14,42,14 61 s55.333,4.667,60,6.667s32.668,7.254,43.334,31.627L255,93.667C255,93.667,217,59,169.667,50.333z"/> 62 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M75.667,123c0,0,42,8,78,8.667s32.667,10.667,32.667,10.667 63 S185.333,155,146.5,153.667S75.667,123,75.667,123z"/> 64 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M45,93c0,0-12.667-24,34-48h-8.667c0,0-35.455,24.559-36,35.677L45,93 65 z"/> 66 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M174.912,161c0,0-24.745,12.999-24.745,12.333 67 s-15.25-4.249-20.583-10.416"/> 68 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M130,162.667c0,0,1.75-3.083,13.667-1.25c0,0,30,0.836,30.75-0.582"/> 69 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M177.75,43L224,45.5c0,0,7.5,12.125-13,8.625S177.75,43,177.75,43z"/> 70 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M237.25,52c0,0,2.75,20.375,21.875,35.625l5.75-6.948 71 C264.875,80.677,249.273,55.266,237.25,52z"/> 72 </svg> 73 </body> 74 </html>
恩恩~~写到这里我的肚子饿惨了,他们都下班去吃饭了,打字这么开心我干脆再介绍个插件,那就vivus.js
Vivus是一款可以执行SVG路径动画的轻量级Javascript库,github地址:https://github.com/maxwellito/vivus
扔个中文的介绍http://www.htmleaf.com/html5/SVG/201501261279.html
写的还可以,我就不重复码字了,直接上demo:
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>super</title> 6 <script src="vivus.js"></script> 7 <style> 8 .super_logo{ 9 position: absolute; 10 } 11 #super{ 12 position: absolute; 13 z-index: 1; 14 } 15 </style> 16 </head> 17 <body style="background:#0f1a3a;"> 18 <img src="super.gif" alt="super" class="super_logo"> 19 <svg id="super" x="0px" y="0px" width="293px" height="200px" viewBox="0 0 293 200"> 20 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M67.667,39.667c0,0-33.334,17.333-46.667,36.667 21 c0,0,33.007,40.458,43.331,50.018c19.419,17.982,65.002,55.316,82.169,59.982c0,0,27.834-11.334,49.834-30.667S249,113,261,100 22 s9.334-12.333,15.334-22.333c0,0-21.333-29.333-44-38c0,0-162.001-5.334-163.334-2.667"/> 23 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M169.667,50.333c0,0-71.334-2.667-74.667,8.667s42,14,42,14 24 s55.333,4.667,60,6.667s32.668,7.254,43.334,31.627L255,93.667C255,93.667,217,59,169.667,50.333z"/> 25 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M75.667,123c0,0,42,8,78,8.667s32.667,10.667,32.667,10.667 26 S185.333,155,146.5,153.667S75.667,123,75.667,123z"/> 27 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M45,93c0,0-12.667-24,34-48h-8.667c0,0-35.455,24.559-36,35.677L45,93 28 z"/> 29 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M174.912,161c0,0-24.745,12.999-24.745,12.333 30 s-15.25-4.249-20.583-10.416"/> 31 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M130,162.667c0,0,1.75-3.083,13.667-1.25c0,0,30,0.836,30.75-0.582"/> 32 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M177.75,43L224,45.5c0,0,7.5,12.125-13,8.625S177.75,43,177.75,43z"/> 33 <path fill="none" data-duration="60" stroke="#ffffff" stroke-width="1" d="M237.25,52c0,0,2.75,20.375,21.875,35.625l5.75-6.948 34 C264.875,80.677,249.273,55.266,237.25,52z"/> 35 </svg> 36 <script> 37 window.onload=function(){ 38 var toPlay= new Vivus('super', { 39 type: 'delayed', 40 duration: 50, 41 start: 'autostart', 42 forceRender: false, 43 dashGap: 20} 44 ); 45 var oSuper=document.getElementById('super'); 46 oSuper.addEventListener('click',function(){ 47 toPlay.reset().play(); 48 }); 49 }; 50 </script> 51 </body> 52 </html>
以上~~如果大家觉得有意思,点个赞呗,关注下也就更好了
他们吃饭都回来了,我也终于要走了,实习狗下班