将UIScrollViewPoint转换为UIImage + ZOOM + ROTATE

我需要裁剪UIImage ，它在UIScrollview加载了另一个UIView矩形，它也在UIScrollView

以下是视图层次结构

  --> View --> UIScrollView --> viewBase (UIView) --> UIImageView -> (Zoomed & rotated ) --> UIView (Target View)(Movable User can move anywhere in scrollview to crop rect) 

我的图像是旋转和缩放我需要在TargetView获取图像的精确部分

我在context使用旋转绘制UIImage是代码

 CGFloat angleCroppedImageRetreacted = atan2f(self.imgVPhoto.transform.b, self.imgVPhoto.transform.a); angleCroppedImageRetreacted = angleCroppedImageRetreacted * (180 / M_PI); UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, self.imgVPhoto.image.size.width, self.imgVPhoto.image.size.height)]; rotatedViewBox.transform = CGAffineTransformMakeRotation(-angleCroppedImageRetreacted); CGSize rotatedSize = rotatedViewBox.frame.size; UIGraphicsBeginImageContext(rotatedSize); CGContextRef bitmap = UIGraphicsGetCurrentContext(); CGContextTranslateCTM(bitmap, rotatedSize.width / 2.0f, rotatedSize.height / 2.0f); CGContextRotateCTM(bitmap, -angleCroppedImageRetreacted); CGContextScaleCTM(bitmap, 1.0f, -1.0f); CGContextDrawImage(bitmap, CGRectMake(-self.imgVPhoto.image.size.width / 2.0f, -self.imgVPhoto.image.size.height / 2.0f, self.imgVPhoto.image.size.width, self.imgVPhoto.image.size.height), self.imgVPhoto.image.CGImage); UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); 

它工作正常。 我正在使用模拟器中的旋转UIImage

为了将目标视图点转换为UIImage我使用以下不工作的代码

  CGPoint imageViewPoint = [self.viewBase convertPoint:self.targetImageview.center toView:self.imgVPhoto]; float percentX = imageViewPoint.x / self.imgVPhoto.frame.size.width; float percentY = imageViewPoint.y / self.imgVPhoto.frame.size.height; CGPoint imagePoint = CGPointMake(resultImage.size.width * percentX, resultImage.size.height * percentY); rect.origin = imagePoint; //rect.origin.x *= (self.imgVPhoto.image.size.width / self.imgVPhoto.frame.size.width); //rect.origin.y *= (self.imgVPhoto.image.size.height / self.imgVPhoto.frame.size.height); imageRef = CGImageCreateWithImageInRect([resultImage CGImage], rect); img = [UIImage imageWithCGImage:imageRef scale:viewImage.scale orientation:viewImage.imageOrientation]; 

我认为问题是我们不能在Transform Apply之后使用Rect

请帮助我裁剪UIImage ，它在相同的层次结构上从rect缩放和旋转

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Answer 1

我在回答我自己的问题。

感谢Matic给出了一个想法

我改变了逻辑

我已经实现了我想要的function

 CGPoint locationInImageView = [self.viewBase convertPoint:self.targetImageview.center toView:self.view]; // received from touch locationInImageView = [self.view convertPoint:locationInImageView toView:self.imgVPhoto]; // I GOT LOCATION IN UIIMAGEVIEW OF TOUCH POINT UIGraphicsBeginImageContextWithOptions(self.view.frame.size, NO, 0); [self.imgVPhoto.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *img1 = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); // I GOT UIIMAGE FROM CURRENT CONTEXT CGFloat width = self.targetImageview.frame.size.width * self.zoomScale ; CGFloat height = self.targetImageview.frame.size.height * self.zoomScale ; //2 IS SCALE FACTOR CGFloat xPos = (locationInImageView.x * 2) - width / 2; CGFloat yPos = (locationInImageView.y * 2) - height / 2; CGRect rect1 = CGRectMake(xPos, yPos, width, height); CGImageRef imageRef = CGImageCreateWithImageInRect([img1 CGImage], rect1); // YAHHH YOU HAVE EXACT IMAGE UIImage *img = [UIImage imageWithCGImage:imageRef scale:img1.scale orientation:img1.imageOrientation];