需求如下图
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>javascript己知点坐标和半径R，求每隔45度半径与同心圆交汇的坐标</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<style>
span {
position: absolute;
color: red;
font-weight:bold;
}
</style>
</head>
<body>
<script>
var showCircle = function () {
var PI = Math.PI;
return {
draw: function (r, _x, _y) {
var x, y;
var _pt = [];
for (var i = 0; i < 360; i += 45) {
x = Math.cos(PI / 180 * i) * r + _x;
y = Math.sin(PI / 180 * i) * r + _y;
var O = document.createElement(‘span‘);
O.appendChild(document.createTextNode(‘.‘));
document.body.appendChild(O);
O.style.left = x + ‘px‘;
O.style.top = y + ‘px‘;
let pt = { x, y };
_pt.push(pt);
}
Points.push(_pt);
}
}
}();
var Points = [];
for (let r = 80; r < 200; r+=20){
showCircle.draw(r, 200, 200);
}
console.log(Points);
</script>
</body>
</html>
原文地址：https://www.cnblogs.com/zzws/p/8824783.html
时间： 2024-08-28 01:52:05