blocks|key|823479|text|你可以试着这样做。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|823480|+var+path+=+UIBezierPath()
+var+shapeLayer+=+CAShapeLayer()
+var+cropImage+=+UIImage()


+override+func+touchesBegan(_+touches:+Set<UITouch>,+with+event:+UIEvent?)+{
++++if+let+touch+=+touches.first+as+UITouch?{
++++++++let+touchPoint+=+touch.location(in:+self.YourimageView)
++++++++print("touch+begin+to+:+\(touchPoint)")
++++++++path.move(to:+touchPoint)
++++}
}

override+func+touchesMoved(_+touches:+Set<UITouch>,+with+event:+UIEvent?)+{
++++if+let+touch+=+touches.first+as+UITouch?{
++++++++let+touchPoint+=+touch.location(in:+self.YourimageView)
++++++++print("touch+moved+to+:+\(touchPoint)")
++++++++path.addLine(to:+touchPoint)
++++++++addNewPathToImage()
++++}
}

override+func+touchesEnded(_+touches:+Set<UITouch>,+with+event:+UIEvent?)+{
++++if+let+touch+=+touches.first+as+UITouch?{
++++++++let+touchPoint+=+touch.location(in:+self.YourimageView)
++++++++print("touch+ended+at+:+\(touchPoint)")
++++++++path.addLine(to:+touchPoint)
++++++++addNewPathToImage()
++++++++path.close()
++++}
}
+func+addNewPathToImage(){
++++shapeLayer.path+=+path.cgPath
++++shapeLayer.strokeColor+=+strokeColor.cgColor
++++shapeLayer.fillColor+=+UIColor.clear.cgColor
++++shapeLayer.lineWidth+=+lineWidth
++++YourimageView.layer.addSublayer(shapeLayer)
}
+++func+cropImage(){

++++UIGraphicsBeginImageContextWithOptions(YourimageView.bounds.size,+false,+1)
++++tempImageView.layer.render(in:+UIGraphicsGetCurrentContext()!)
++++let+newImage+=+UIGraphicsGetImageFromCurrentImageContext()
++++UIGraphicsEndImageContext()
++++self.cropImage+=+newImage!
++++}


++++@IBAction+func+btnCropImage(_+sender:+Any)+{
+++++++++cropImage()
++++}|code-block|syntax|javascript|823481|在特定按钮操作上绘制路径后，只需调用您的imageByApplyingMaskingBezierPath|offset|length|style|CODE|823482|entityMap^0|0|0|K|W|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

You can try like this.

<pre><code> var path = UIBezierPath()
 var shapeLayer = CAShapeLayer()
 var cropImage = UIImage()


 override func touchesBegan(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
 if let touch = touches.first as UITouch?{
 let touchPoint = touch.location(in: self.YourimageView)
 print("touch begin to : \(touchPoint)")
 path.move(to: touchPoint)
 }
}

override func touchesMoved(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
 if let touch = touches.first as UITouch?{
 let touchPoint = touch.location(in: self.YourimageView)
 print("touch moved to : \(touchPoint)")
 path.addLine(to: touchPoint)
 addNewPathToImage()
 }
}

override func touchesEnded(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
 if let touch = touches.first as UITouch?{
 let touchPoint = touch.location(in: self.YourimageView)
 print("touch ended at : \(touchPoint)")
 path.addLine(to: touchPoint)
 addNewPathToImage()
 path.close()
 }
}
 func addNewPathToImage(){
 shapeLayer.path = path.cgPath
 shapeLayer.strokeColor = strokeColor.cgColor
 shapeLayer.fillColor = UIColor.clear.cgColor
 shapeLayer.lineWidth = lineWidth
 YourimageView.layer.addSublayer(shapeLayer)
}
 func cropImage(){

 UIGraphicsBeginImageContextWithOptions(YourimageView.bounds.size, false, 1)
 tempImageView.layer.render(in: UIGraphicsGetCurrentContext()!)
 let newImage = UIGraphicsGetImageFromCurrentImageContext()
 UIGraphicsEndImageContext()
 self.cropImage = newImage!
 }


 @IBAction func btnCropImage(_ sender: Any) {
 cropImage()
 }
</code></pre>

Once you draw a path on particular button action just call your <code>imageByApplyingMaskingBezierPath</code>

blocks|key|411224|text|您需要将path.cgPath添加到当前上下文中，还需要删除context.saveGState()和context.restoreGState()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|411225|使用此代码|BOLD|411226|func+imageByApplyingMaskingBezierPath(_+path:+UIBezierPath,+_+pathFrame:+CGRect)+->+UIImage+{

++++++++++++UIGraphicsBeginImageContext(self.size)
++++++++++++let+context+=+UIGraphicsGetCurrentContext()!

++++++++++++context.addPath(path.cgPath)
++++++++++++context.clip()
++++++++++++draw(in:+CGRect(x:+0,+y:+0,+width:+self.size.width,+height:+self.size.height))

++++++++++++let+maskedImage+=+UIGraphicsGetImageFromCurrentImageContext()!

++++++++++++UIGraphicsEndImageContext()

++++++++++++return+maskedImage
++++++++}|code-block|syntax|javascript|411227|使用it的|411228|let+testPath+=+UIBezierPath()
testPath.move(to:+CGPoint(x:+self.imageView.frame.width+/+2,+y:+self.imageView.frame.height))
testPath.addLine(to:+CGPoint(x:+0,+y:+0))
testPath.addLine(to:+CGPoint(x:+self.imageView.frame.width,+y:+0))
testPath.close()

self.imageView.image+=+UIImage(named:"Image")?.imageByApplyingMaskingBezierPath(testPath,+self.imageView.frame)|411229|结果|411230|​|411231|📷|atomic|411232|411233|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/55c893bca42ca13a98bf46f8a56c9e4d.png|imageAlt^0|4|B|U|K|1F|N|0|0|5|0|0|0|0|0|2|0|0|0|1|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@$9|19|A|1A|B|C]|$9|1B|A|1C|B|C]|$9|1D|A|1E|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1F|8|@$9|1G|A|1H|B|H]]|D|@]|E|$]]|$1|I|3|J|5|K|7|1I|8|@]|D|@]|E|$L|M]]|$1|N|3|O|5|6|7|1J|8|@]|D|@]|E|$]]|$1|P|3|Q|5|K|7|1K|8|@]|D|@]|E|$L|M]]|$1|R|3|S|5|6|7|1L|8|@$9|1M|A|1N|B|H]]|D|@]|E|$]]|$1|T|3|U|5|6|7|1O|8|@]|D|@]|E|$]]|$1|V|3|W|5|X|7|1P|8|@]|D|@$9|1Q|A|1R|1|1S]]|E|$]]|$1|Y|3|U|5|6|7|1T|8|@]|D|@]|E|$]]|$1|Z|3|-4|5|6|7|1U|8|@]|D|@]|E|$]]]|10|$11|$5|12|13|14|E|$15|16|17|-4]]]]

You need to add your <code>path.cgPath</code> to your current context, also you need to remove <code>context.saveGState()</code> and <code>context.restoreGState()</code>

Use this code

<pre><code>func imageByApplyingMaskingBezierPath(_ path: UIBezierPath, _ pathFrame: CGRect) -&gt; UIImage {

 UIGraphicsBeginImageContext(self.size)
 let context = UIGraphicsGetCurrentContext()!

 context.addPath(path.cgPath)
 context.clip()
 draw(in: CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height))

 let maskedImage = UIGraphicsGetImageFromCurrentImageContext()!

 UIGraphicsEndImageContext()

 return maskedImage
 }
</code></pre>

Using it

<pre><code>let testPath = UIBezierPath()
testPath.move(to: CGPoint(x: self.imageView.frame.width / 2, y: self.imageView.frame.height))
testPath.addLine(to: CGPoint(x: 0, y: 0))
testPath.addLine(to: CGPoint(x: self.imageView.frame.width, y: 0))
testPath.close()

self.imageView.image = UIImage(named:"Image")?.imageByApplyingMaskingBezierPath(testPath, self.imageView.frame)
</code></pre>

Result

<a href="https://i.stack.imgur.com/UcNaZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UcNaZ.png" alt="enter image description here"></a>

blocks|key|411240|text|以下是基于UIBezierPath从图像中获取剪辑的Swift代码，它的实现速度非常快。如果图像已经显示在屏幕上，则此方法有效，这种情况最常见。合成的图像将有一个透明的背景，这是大多数人在剪辑照片图像的一部分时想要的。您可以在本地使用得到的裁剪图像，因为您将把它放在我称为imageWithTransparentBackground的UIImage对象中。这段非常简单的代码还向您展示了如何将图像保存到相机胶卷，以及如何将其直接放到粘贴板中，以便用户可以直接将该图像粘贴到文本消息中，粘贴到便笺、电子邮件等中。请注意，为了将图像写入相机胶卷，您需要编辑info.plist并提供原因，以了解“隐私-图片库使用说明”|type|unstyled|depth|inlineStyleRanges|entityRanges|data|411241|import+Photos+//+Needed+if+you+save+to+the+camera+roll|code-block|syntax|javascript|411242|提供用于裁剪的UIBezierPath。这是我对其中之一的声明。|411243|let+clipPath+=+UIBezierPath()|411244|使用一些命令组合，用您自己的一些逻辑填充clipPath。下面是我在绘图逻辑中使用的一些代码。为aPointOnScreen提供CGPoint等效项，等构建相对于主屏幕的路径，因为self.view是此应用程序的ViewController+(对于此代码)，并且self.view.layer通过clipPath呈现。|411245|clipPath.move(to:+aPointOnScreen)
clipPath.addLine(to:+otherPointOnScreen)
clipPath.addLine(to:+someOtherPointOnScreen)

clipPath.close()|411246|此逻辑使用所有设备屏幕作为上下文大小。为此声明了一个CGSize。fullScreenX和fullScreenY是我已经捕获了设备宽度和高度的变量。如果你正在裁剪的照片已经放大，并且在整个屏幕上显示的大小足够大，那就更好了。你所看到的就是你所得到的。|411247|let+mainScreenSize+=++CGSize(width:+fullScreenX,+height:+fullScreenY)

//+Get+an+empty+context
UIGraphicsBeginImageContext(mainScreenSize)
//+Specify+the+clip+path
clipPath.addClip()
//+Render+through+the+clip+path+from+the+whole+of+the+screen.
self.view.layer.render(in:+UIGraphicsGetCurrentContext()!)
//+Get+the+clipped+image+from+the+context
let+image+:+UIImage+=+UIGraphicsGetImageFromCurrentImageContext()!
//+Done+with+the+context,+so+end+it.
UIGraphicsEndImageContext()
++++++++++++++++
//+The+PNG+data+has+the+alpha+channel+for+the+transparent+background
let+imageData+=+image.pngData()
//+Below+is+the+local+UIImage+to+use+within+your+code
let+imageWithTransparentBackground+=+UIImage.init(data:+imageData!)
//+Make+the+image+available+to+the+pasteboard.
UIPasteboard.general.image+=+imageWithTransparentBackground
//+Save+the+image+to+the+camera+roll.
PHPhotoLibrary.shared().performChanges({
++++++++++++++++++++PHAssetChangeRequest.creationRequestForAsset(from:+imageWithTransparentBackground!)
++++++++++++++++},+completionHandler:+{+success,+error+in
++++++++++++++++++++if+success+{
++++++++++++++++++++++++//
++++++++++++++++++++}
++++++++++++++++++++else+if+let+error+=+error+{
++++++++++++++++++++++++//
++++++++++++++++++++}
++++++++++++++++++++else+{
++++++++++++++++++++++++//
++++++++++++++++++++}
++++++++++++++++})|411248|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|Y|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

Here is Swift code to get clips from an image based on a UIBezierPath and it is very quickly implemented. This method works if the image is already being shown on the screen, which will most often be the case. The resultant image will have a transparent background, which is what most people want when they clip part of a photo image. You can use the resultant clipped image locally because you will have it in a UIImage object that I called imageWithTransparentBackground. This very simple code also shows you how to save the image to the camera roll, and how to also put it right into the pasteboard so a user can paste that image directly into a text message, paste it into Notes, an email, etc. Note that in order to write the image to the camera roll, you need to edit the info.plist and provide a reason for “Privacy - Photo Library Usage Description”
<pre><code>import Photos // Needed if you save to the camera roll
</code></pre>
Provide a UIBezierPath for clipping. Here is my declaration for one.
<pre><code>let clipPath = UIBezierPath()
</code></pre>
Populate the clipPath with some logic of your own using some combination of commands. Below are a few I used in my drawing logic. Provide CGPoint equivalents for aPointOnScreen, etc Build your path relative to the main screen as self.view is this apps ViewController (for this code), and self.view.layer is rendered through the clipPath.
<pre><code> 
clipPath.move(to: aPointOnScreen)
clipPath.addLine(to: otherPointOnScreen)
clipPath.addLine(to: someOtherPointOnScreen)

clipPath.close()

</code></pre>
This logic uses all of the devices screen as the context size. A CGSize is declared for that. fullScreenX and fullScreenY are my variables where I have already captured the devices width and height. It is nice if the photo you are clipping from is already zoomed into and is an adequate size as shown on the whole of the screen. What you see, is what you get.
<pre><code> 
let mainScreenSize = CGSize(width: fullScreenX, height: fullScreenY)

// Get an empty context
UIGraphicsBeginImageContext(mainScreenSize)
// Specify the clip path
clipPath.addClip()
// Render through the clip path from the whole of the screen.
self.view.layer.render(in: UIGraphicsGetCurrentContext()!)
// Get the clipped image from the context
let image : UIImage = UIGraphicsGetImageFromCurrentImageContext()!
// Done with the context, so end it.
UIGraphicsEndImageContext()
 
// The PNG data has the alpha channel for the transparent background
let imageData = image.pngData()
// Below is the local UIImage to use within your code
let imageWithTransparentBackground = UIImage.init(data: imageData!)
// Make the image available to the pasteboard.
UIPasteboard.general.image = imageWithTransparentBackground
// Save the image to the camera roll.
PHPhotoLibrary.shared().performChanges({
 PHAssetChangeRequest.creationRequestForAsset(from: imageWithTransparentBackground!)
 }, completionHandler: { success, error in
 if success {
 //
 }
 else if let error = error {
 //
 }
 else {
 //
 }
 })
</code></pre>

I would like to clip a bezier path from an image. For some reason, the image remains the unclipped. And how do I position the path so it would be properly cut? 

<pre><code>extension UIImage {

func imageByApplyingMaskingBezierPath(_ path: UIBezierPath, _ pathFrame: CGFrame) -&gt; UIImage {

 UIGraphicsBeginImageContext(self.size)
 let context = UIGraphicsGetCurrentContext()!
 context.saveGState()

 path.addClip()
 draw(in: CGRect(x: 0, y: 0, width: self.size.width, height: self.size.height))

 let maskedImage = UIGraphicsGetImageFromCurrentImageContext()!

 context.restoreGState()
 UIGraphicsEndImageContext()

 return maskedImage
}

}
</code></pre>

<a href="https://i.stack.imgur.com/CDFGH.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CDFGH.jpg" alt="example"></a>

Swift - Clipping image with UIBezierPath

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我想从图像中裁剪bezier路径。由于某些原因，图像仍然是未剪裁的。我如何定位路径，使其被正确剪切？extension UIImage {func imageByApplyingMaskingBezierPath(_ path: UIBezierPath, _ pathFrame: CGFrame) -> UIImag...

问使用UIBezierPath快速裁剪图像
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