<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>canvas</title>
<script type="text/javascript" src="../js/jQuery.js"></script>
<style type="text/css">
*{
margin: 0;
padding: 0;
outline: none;
border: none;
}
#canvas{
width: 7rem;
margin: .25rem 0 0 1.5rem;
border: 1px solid black;
}
</style>
</head>
<body>
<canvas id="canvas" width="1000" height="600"></canvas>
</body>
</html>
<script type="text/javascript">
/**
* rem 布局初始化
*/
$('html').css('font-size', $(window).width()/10);
/**
* 获取 canvas 画布
* 获取 canvas 绘图上下文环境
*/
var canvas = $('#canvas')[0];
var cxt = canvas.getContext('2d');
/**
* 图形变换矩阵( 默认情况下是一个单位举证 )
* 一个三维正矩阵 transform 的效果会累计, 直到遇到 setTransform
* a, c, e | 1, 0, 0
* b, d, f | 0, 1, 0
* 0, 0, 1 | 0, 0, 1
* transform(水平缩放a, 水平倾斜b, 垂直倾斜c, 垂直缩放d, 水平位移e, 垂直位移f)
*/
cxt.fillStyle = 'red';
cxt.strokeStyle = '#058';
cxt.lineWidth = 5;
cxt.save();
cxt.transform(1, 0, 0, 1, 100, 100);
cxt.transform(1.5, 0, 0, 1.5, 0, 0);
cxt.transform(1, 0.2, 0.2, 1, 0, 0);
//cxt.setTransform(1, 0, 0, 1, 0, 0);
cxt.fillRect(50, 50, 100, 100);
cxt.strokeRect(50, 50, 100, 100);
cxt.restore();
</script>