HTML canvas rotate() 方法
定义和用法
rotate() 旋转当前绘图的方法。
实例
将矩形旋转20度：
JavaScript:
var c=document.getElementById("myCanvas");
var ctx=c.getContext("2d");
ctx.rotate(20 * Math.PI / 180);
ctx.fillRect(50,20,100,50);
Syntax
context.rotate(angle);
Parameter Value
| Parameter | Description |
|---|---|
| angle |
Rotation angle, in radians. To convert degrees to radians, please use the formula degrees * Math.PI / 180 for calculation. Example: To rotate 5 degrees, you can specify the following formula: 5 * Math.PI / 180. |
Browser Support
The numbers in the table indicate the first browser version that fully supports this property.
| Chrome | Edge | Firefox | Safari | Opera |
|---|---|---|---|---|
| Chrome | Edge | Firefox | Safari | Opera |
| 4.0 | 9.0 | 3.6 | 4.0 | 10.1 |
Note:Internet Explorer 8 and earlier versions do not support the <canvas> element.
