canvas雪花

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>canvas雪花</title>
</head>
<body>
<canvas id="canvas"></canvas>

<script>
    var c = document.getElementById("canvas").getContext("2d");
    c.width = window.innerWidth;
    c.height = window.innerHeight;
    var deg = Math.PI/180;
    function snowflake(c,n,x,y,len) {
        c.save();
        c.translate(x,y);
        c.moveTo(0,0);
        leg(n);
        c.rotate(-120*deg);
        leg(n);
        c.rotate(-120*deg);
        leg(n);
        c.closePath();
        c.restore();

        function leg(n) {
            c.save();
            if(n == 0){
                c.lineTo(len,0);
            }else{
                c.scale(1/3,1/3);
                leg(n-1);
                c.rotate(60*deg);
                leg(n-1);
                c.rotate(-120*deg);
                leg(n-1);
                c.rotate(60*deg);
                leg(n-1);
            }
            c.restore();
            c.translate(len,0);

        }
    }
    snowflake(c,6,115,115,125);
    c.stroke();
</script>
</body>
</html>