<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>（四）canvas绘制路径</title>
</head>
<style>
* {margin: 0;padding: 0;}
body { background-color: black; }
#c1 { background-color: #fff; }
</style>
<body>
<canvas id="c1" width="400" height="400"></canvas>
<script>
function $(id) {
return document.getElementById(id);
}
var c1 = $("c1");
var ctx = c1.getContext("2d");
ctx.lineWidth = 20;//改变画出的图形的边框粗细，需要写在前面
ctx.save();
ctx.strokeStyle = "red";
ctx.shadowOffsetX = 10;//阴影x轴的距离
ctx.shadowOffsetY = 10;//阴影y轴的距离
ctx.shadowBlur = 5;//模糊
ctx.shadowColor = "blue";//阴影的颜色
ctx.beginPath();
ctx.moveTo(100,200);
ctx.lineTo(100,300);
ctx.lineTo(200,300);
ctx.closePath();
ctx.stroke();
ctx.restore();
ctx.beginPath();
ctx.moveTo(0,100);
ctx.lineTo(0,200);
ctx.lineTo(100,200);
ctx.closePath();
ctx.stroke();
ctx.clearRect(50,50,100,100);//清除可以理解为橡皮擦
//ctx.clearRect(0,0,oC.width,oC.height);//清除整个画布
</script>
</body>
</html>
