镜像

作者: antlove | 来源:发表于2019-07-23 09:18 被阅读0次

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>镜像</title>
    <style>
        body{
            background-color:#eee;
        }
        #canvas{
            background-color:#fff;
            margin-left:10px;
            margin-top:10px;
            -box-shadow:4px 4px 8px rgba(0,0,0,0.5);
        }
    </style>
</head>
<body>

    <canvas id="canvas" width="800" height="600"></canvas>

    <script>
        var canvas = document.getElementById("canvas");
        var ctx = canvas.getContext("2d");

        drawHalfCircle();

        ctx.translate(canvas.width,0);
        ctx.scale(-1,1);
        
        drawHalfCircle();

        function drawHalfCircle(){
            ctx.beginPath();
            ctx.arc(100, 75, 50, 0.5 * Math.PI, 1.5 * Math.PI);
            ctx.stroke();
        }

    </script>
</body>
</html>

镜像.png