transform

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    // 清空transform，以前的平移、缩放、旋转都会消失
    [UIView animateWithDuration:2.0 animations:^{
        self.tempView.transform = CGAffineTransformIdentity;

    }];

//    self.angle += M_PI_4;

//    [UIView animateWithDuration:1.0 animations:^{
////        self.tempView.transform = CGAffineTransformScale(self.tempView.transform, 0.8, 0.8);
//        self.tempView.transform = CGAffineTransformRotate(self.tempView.transform, M_PI_4);
//    }];


    // transform:形变属性，能完成的功能：平移、缩放、旋转
//    [UIView animateWithDuration:2.0 animations:^{
//        // 缩放
//        self.tempView.transform = CGAffineTransformMakeScale(0.5, 0.5);
//        // 平移
//        self.tempView.transform = CGAffineTransformMakeTranslation(-100, 100);
        // 旋转
//        self.tempView.transform = CGAffineTransformMakeRotation(-M_PI_4);

//        CGAffineTransform translation = CGAffineTransformMakeTranslation(-100, 100);
//        CGAffineTransform scaleTranslation = CGAffineTransformScale(translation, 0.5, 0.5);
//        CGAffineTransform rotateScaleTranslation = CGAffineTransformRotate(scaleTranslation, M_PI_2);
//        self.tempView.transform = rotateScaleTranslation;
//    }];
}