[知识点随笔] UIView--transform 属性

transform 属性
- 旋转
* CGAffineTransformMakeRotation(CGFloat angle)
* CGAffineTransformRotate(CGAffineTransform t, CGFloat angle);

- 缩放
* CGAffineTransformMakeScale(CGFloat sx, CGFloat sy);
* CGAffineTransformScale(CGAffineTransform t, CGFloat sx, CGFloat sy);

- 平移
* CGAffineTransformMakeTranslation(CGFloat tx,  CGFloat ty) ;
* CGAffineTransformTranslate(CGAffineTransform t, CGFloat tx, CGFloat ty);

- 默认值
* CGAffineTransformIdentity