第一次，用@font-face 将文本绘制到 < 画布 > 不起作用
当我用@font-face 加载的字体在画布上绘制文本时，文本不能正确显示。它根本没有显示(在 Chrome13和 Firefox5中) ，或者字体是错误的(Opera 11)。这种类型的意外行为仅在第一次使用该字体绘制时发生。之后一切都会好起来的。
这是标准行为还是什么？
谢谢你。
PS: 以下是测试用例的源代码
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>@font-face and <canvas></title>
<style id="css">
@font-face {
font-family: 'Press Start 2P';
src: url('fonts/PressStart2P.ttf');
}
</style>
<style>
canvas, pre {
border: 1px solid black;
padding: 0 1em;
}
</style>
</head>
<body>
<h1>@font-face and <canvas></h1>
<p>
Description: click the button several times, and you will see the problem.
The first line won't show at all, or with a wrong typeface even if it does.
<strong>If you have visited this page before, you may have to refresh (or reload) it.</strong>
</p>
<p>
<button id="draw">#draw</button>
</p>
<p>
<canvas width="250" height="250">
Your browser does not support the CANVAS element.
Try the latest Firefox, Google Chrome, Safari or Opera.
</canvas>
</p>
<h2>@font-face</h2>
<pre id="view-css"></pre>
<h2>Script</h2>
<pre id="view-script"></pre>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script id="script">
var x = 30,
y = 10;
$('#draw').click(function () {
var canvas = $('canvas')[0],
ctx = canvas.getContext('2d');
ctx.font = '12px "Press Start 2P"';
ctx.fillStyle = '#000';
ctx.fillText('Hello, world!', x, y += 20);
ctx.fillRect(x - 20, y - 10, 10, 10);
});
</script>
<script>
$('#view-css').text($('#css').text());
$('#view-script').text($('#script').text());
</script>
</body>
</html>
