transform:形变属性

• 平移(Translation)

    CGAffineTransform CGAffineTransformMakeTranslation(CGFloat tx, CGFloat ty);
  
    self.tempView.transform = CGAffineTransformMakeTranslation(-100, 100);
  

• 缩放(Scale)，值范围：0-1

    CGAffineTransform CGAffineTransformMakeScale(CGFloat sx, CGFloat sy);
  
    self.tempView.transform = CGAffineTransformMakeScale(0.5, 0.5);
  

• 旋转(Rotation)

    CGAffineTransform CGAffineTransformMakeRotation(CGFloat angle);
  
    self.tempView.transform = CGAffineTransformMakeRotation(-M_PI_4);
  

• 效果重叠

    // 在原有形变基础上叠加 平移
    CGAffineTransform CGAffineTransformTranslate(CGAffineTransform t,
      CGFloat tx, CGFloat ty);
  
    // 在原有形变基础上叠加 缩放
    CGAffineTransform CGAffineTransformScale(CGAffineTransform t,
      CGFloat sx, CGFloat sy);
  
    // 在原有形变基础上叠加 旋转
    CGAffineTransform CGAffineTransformRotate(CGAffineTransform t,
      CGFloat angle);
  
    // 先平移
    CGAffineTransform translation = CGAffineTransformMakeTranslation(-100, 100);
  
    // 再缩放
    CGAffineTransform scaleTranslation = CGAffineTransformScale(translation, 0.5, 0.5);
  
    // 最后旋转
    CGAffineTransform rotateScaleTranslation = CGAffineTransformRotate(scaleTranslation, M_PI_2);
  
    self.tempView.transform = rotateScaleTranslation;
  

• CGAffineTransformIdentity用于清空transform(变换)，以前的平移、缩放、旋转都会消失

    [UIView animateWithDuration:2.0 animations:^{
        self.tempView.transform = CGAffineTransformIdentity;
    }];