基于HTML5陀螺仪实现ofo首页眼睛移动效果

àì夳堔傛蜴生んèń 2023-06-10 11:29 45阅读 0赞

最近用ofo小黄车App的时候，发现以前下方扫一扫变成了一个眼睛动的小黄人，觉得蛮有意思的，这里用HTML5仿一下效果。

## ofo眼睛效果 ##

![1302312-20180102221959831-207230921.gif][]

## 效果分析 ##

从效果中不难看出，是使用陀螺仪事件实现的。

这里先来看一下HTML5中陀螺仪事件的一些概念。

陀螺仪事件为deviceorientation，这里主要获取事件中的alpha,beta,gamma。

### aplha ###

行动装置水平放置时，绕 Z 轴旋转的角度，数值为 0 度到 360 度。  
![1302312-20180102222017409-364540391.jpg][]

### beta ###

行动装置水平放置时，绕 X 轴旋转的角度，数值为 -180 度到 180 度。  
![1302312-20180102222043284-547799148.jpg][]

### gamma ###

行动装置水平放置时，绕 Y 轴旋转的角度，数值为 -90 度到 90 度。

![1302312-20180102222057503-371799476.jpg][]

这里，只需要用到beta和gamma。

将apk解压，得到眼睛素材：  
![1302312-20180102222106456-753214858.png][]

## 代码实现 ##

<!DOCTYPE html>
    <html lang="en">
    <head>
      <meta charset="UTF-8">
      <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
      <title>Document</title>
      <style>
        #box{
          position: relative;
          width: 300px;
          margin: 0 auto;
        }
    
        #face{
          background-image: url(images/face.png);
          background-size: cover;
          width: 300px;
          height: 300px;
          position: absolute;
        }
    
        #eyeLeft{
          background-image: url(images/eye.png);
          background-size: cover;
          width: 40px;
          height: 40px;
          position: absolute;
          top: 90px;
          left: 100px;
        }
    
        #eyeRight{
          background-image: url(images/eye.png);
          background-size: cover;
          width: 40px;
          height: 40px;
          position: absolute;
          top: 90px;
          left: 190px;
        }
    
        #glass{
          background-image: url(images/glass.png);
          background-size: cover;
          width: 300px;
          height: 300px;
          position: absolute;
        }
      </style>
    </head>
    <body>
      <div id="box">
        <div id="face"></div>
        <div id="eyeLeft"></div>
        <div id="eyeRight"></div>
        <div id="glass"></div>
        <div id="log"></div>
      </div>
    <script>
    'use strict';
    
    /*
    * author: 王乐平
    * blog: http://blog.csdn.net/lecepin
    * date:2017.7.17
    */
    
    var eyeLeftPosition = {
      start: [70, 78],
      end: [100, 110]
    };
    
    var eyeRightPosition = {
      start: [150, 78],
      end: [190, 110]
    };
    
    var eyeLeftCenterPosition = {
      x: (eyeLeftPosition.end[0] - eyeLeftPosition.start[0]) / 2   eyeLeftPosition.start[0],
      y: (eyeLeftPosition.end[1] - eyeLeftPosition.start[1]) / 2   eyeLeftPosition.start[1]
    };
    
    var eyeRightCenterPosition = {
      x: (eyeRightPosition.end[0] - eyeRightPosition.start[0]) / 2   eyeRightPosition.start[0],
      y: (eyeRightPosition.end[1] - eyeRightPosition.start[1]) / 2   eyeRightPosition.start[1]
    };
    
    var r = 20;
    
    var eyeLeft = document.querySelector('#eyeLeft');
    var eyeRight = document.querySelector('#eyeRight');
    
    if (window.DeviceOrientationEvent) {
    
      window.addEventListener('deviceorientation', function (event) {
    
        let {alpha, beta, gamma} = event;
    
        eyeLeft.style.left = eyeLeftCenterPosition.x   gamma / 90 * r   'px';
        eyeRight.style.left = eyeRightCenterPosition.x   gamma / 90 * r   'px';
        eyeLeft.style.top = eyeRight.style.top 
                          = eyeLeftCenterPosition.y   beta / 180 * r   'px';
    
        eyeRight.style.transform = eyeLeft.style.transform 
                             = eyeRight.style.WebkitTransform 
                             = eyeLeft.style.WebkitTransform 
                             = 'rotate('   beta   'deg)';
      }, false);
    } else {
      document.querySelector('body').innerHTML = '浏览器不支持DeviceOrientationEvent';
    }
    </script>
    </body>
    </html>

## 最终效果 ##

![1302312-20180102222134503-545409613.gif][]

![1302312-20180102222140315-11809166.png][]

博客名称：[王乐平博客][Link 1]

CSDN博客地址：[http://blog.csdn.net/lecepin][Link 1]

更多专业前端知识，请上 **【猿2048】www.mk2048.com**

[1302312-20180102221959831-207230921.gif]: /images/20230531/e8d48395e3ff4f33834a9f2a2b322132.png
[1302312-20180102222017409-364540391.jpg]: /images/20230531/192c081db663438bbd6e8bf0fc3b384f.png
[1302312-20180102222043284-547799148.jpg]: /images/20230531/4fa3890dc01245a5b12bb80285a55953.png
[1302312-20180102222057503-371799476.jpg]: /images/20230531/3efc493965a44ad0ae0860d926a41e3a.png
[1302312-20180102222106456-753214858.png]: /images/20230531/7907eae4cd0c4cec91a0bfc3ab7dc554.png
[1302312-20180102222134503-545409613.gif]: /images/20230531/f36294fe5b0d443e87f694ceac227a66.png
[1302312-20180102222140315-11809166.png]: /images/20230531/e79c806441b74ff3ae3255b0cfaccf26.png
[Link 1]: http://blog.csdn.net/lecepin