<html>
<body>
<canvas id="myCanvas" width="300" height="150" style="border:1px solid #d3d3d3;">
您的浏览器不支持 HTML5 canvas 标签。</canvas>
<script>
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
ctx.fillStyle="yellow";
ctx.fillRect(0,0,250,100)
ctx.setTransform(1,0.5,-0.5,1,30,10);
ctx.fillStyle="red";
ctx.fillRect(0,0,250,100);
ctx.setTransform(1,0.5,-0.5,1,30,10);
ctx.fillStyle="blue";
ctx.fillRect(0,0,250,100);
</script>
</body>
</html>