<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html5 canvas旋转</title>
<script src="js/modernizr.js"></script>
</head>
<body>
<script type="text/javascript">
window.addEventListener('load',eventWindowLoaded,false);
function eventWindowLoaded(){
canvasApp();
}
function canvasSupport(){
return Modernizr.canvas;
}
function canvasApp(){
if(!canvasSupport()){
return;
}else{
var theCanvas = document.getElementById('canvas')
var context = theCanvas.getContext("2d")
}
drawScreen();
function drawScreen(){
context.fillStyle="black";
context.fillRect(100,100,50,50);
context.setTransform(1,0,0,1,0,0);
var angleInRadians = 45 * Math.PI / 180;
context.rotate(angleInRadians);
context.fillStyle="red";
context.fillRect(150,100,50,50);
}
}
</script>
<canvas id="canvas" width="500" height="500">
你的浏览器无法使用canvas
小白童鞋；你的支持是我最大的快乐！！
</canvas>
</body>
</html>
context.setTransform(a,b,c,d,e,f);
| a | 水平旋转绘图 |
| b | 水平倾斜绘图 |
| c | 垂直倾斜绘图 |
| d | 垂直缩放绘图 |
| e | 水平移动绘图 |
| f | 垂直移动绘图 |
var angleInRadians = 45 * Math.PI / 180; context.rotate(angleInRadians);
设置函数，调用函数