วาดเงา (shadow) ด้วย HTML5 Canvas

เพื่อวาดเงาด้วย HTML5 Canvas:

<!DOCTYPE HTML>
<html>
  <head>
    <style>
      #test { width: 100px; height: 100px; margin: 0px auto; }
    </style>
    <script>
      function drawShape() {
        var canvas = document.getElementById('mycanvas');
        if (canvas.getContext) {
          var ctx = canvas.getContext('2d');
          ctx.shadowOffsetX = 2;
          ctx.shadowOffsetY = 2;
          ctx.shadowBlur = 2;
          ctx.shadowColor = "rgba(0, 0, 0, 0.5)";
          ctx.font = "20px Times New Roman";
          ctx.fillStyle = "Black";
          ctx.fillText("This is shadow test", 5, 30);
        } else {
          alert('You need Safari or Firefox 1.5+ to see this demo.');
        }
      }
    </script>
  </head>
  <body id="test" onload="drawShape();">
    <canvas id="mycanvas"></canvas>
  </body>
</html>