圆周运动

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .box{20px;height:20px;background: red;border-radius: 50%;position: absolute;left:0;top:0;}
    </style>
</head>
<body>
</body>
<script>
    var t;
    var speed=10;
    var target=315;
    var iNow=225;
    var r=100;
    var center=200;
    document.addEventListener("click",dj,false)
    function dj() {
        clearInterval(t)
        t=setInterval(function () {
            if(iNow>=315){
                clearInterval(t)
            }
            else{
                var div=document.createElement("div")
                div.className="box";
                document.body.appendChild(div)
                iNow+=speed;
                console.log(iNow)
                div.style.left = Math.cos( Math.PI/180*iNow ) * r + center + "px";
                div.style.top=Math.sin(Math.PI/180*iNow)*r+center+"px";
            }
        },30)
    }
</script>
</html>
原文地址:https://www.cnblogs.com/hy96/p/11456118.html