imageView is the photo. I created a copy of the photo called tempImageView and I tried to draw on the tempImageView. However, when I try to draw tempImageView, it enlarges to fill the entire screen.
func createTempImageView(){
tempImageView = UIImageView(frame:CGRect(x: 0, y: 0, width: imageView.image!.size.width, height: imageView.image!.size.height))
tempImageView.center = CGPoint(x: imageView.center.x, y: imageView.center.y)
view.insertSubview(tempImageView, aboveSubview: imageView)
}
Because I set imageView.contentMode = .ScaleAspectFit, the image on screen has a smaller width and height than the original image. However, the imageView.image!.size.width and imageView.image!.size.height refers the original image. Therefore, when I tried to draw on the tempImageView, the image enlarged because tempImageView refers to the original image, which is much larger than the image on screen.
To get the dimensions of the image on screen and to stop the image from enlarging, I did this:
func createTempImageView(){
let widthRatio = imageView.bounds.size.width / imageView.image!.size.width
let heightRatio = imageView.bounds.size.height / imageView.image!.size.height
let scale = min(widthRatio, heightRatio)
let imageWidth = scale * imageView.image!.size.width
let imageHeight = scale * imageView.image!.size.height
tempImageView = UIImageView(frame:CGRect(x: 0, y: 0, width: imageWidth, height: imageHeight))
tempImageView.center = CGPoint(x: imageView.center.x, y: imageView.center.y)
tempImageView.backgroundColor = UIColor.clearColor()
view.insertSubview(tempImageView, aboveSubview: imageView)
}
Related
I want to make a frame image from single image. Below is the code I'm using
func createFrameFromImage(image:UIImage , size :CGSize) -> UIImage
{
let imageSize = CGSize.init(width: size.width , height: size.height)
UIGraphicsBeginImageContext(imageSize)
let width = imageSize.width
let height = imageSize.height
var letTop = image
let rightTop = rotateImageByAngles(image: &letTop, angles: .pi/2) // correct
let rightBottom = rotateImageByAngles(image: &letTop, angles: -.pi) // correct
let leftBottom = rotateImageByAngles(image: &letTop, angles: -.pi/2) // correct
letTop.draw(in: CGRect(x: 0, y: 0, width: width/2, height: height/2))
rightTop.draw(in: CGRect(x: (width/2) , y: 0, width: width/2, height: height/2))
leftBottom.draw(in: CGRect(x: 0, y: height/2, width: width/2, height: height/2))
rightBottom.draw(in: CGRect(x: (width/2) , y: (height/2), width: width/2, height: height/2))
guard let finalImage = UIGraphicsGetImageFromCurrentImageContext() else { return rightTop }
UIGraphicsEndImageContext()
return finalImage
}
Above function takes one piece of image and create four different images by rotating a single at specific angle and merge them to make a frame image. Issue I'm facing is maintaining image ratio. for ex: if create final image of size 320 * 120 it squeezes image horizontally.Attaching screen shot of output. I want to show this new generated image on wall using ARkit.
Final frame image
Given Image
// Adding Frame
// 1 inch = 72 points
//converting size inch to points to create frame image
let frameWidth = (size.width + 1)
let frameHeight = (size.height + 1)
let imgFrameUnit = UIImage(named: "img.png")!
let imgFrame = Singleton.shared.createFrameFromImage(image: imgFrameUnit, size: CGSize(width: frameWidth , height: frameHeight))
let frame = SCNNode(geometry: SCNPlane(width: ((frameWidth * 2.54) / 100), height: ((frameHeight * 2.54) / 100))) // in meters
frame.geometry?.firstMaterial?.diffuse.contents = imgFrame
frame.name = "frame"
nodeWeCanChange?.addChildNode(frame)
Any Help would be really Appreciated?
I am developing an iOS board game. I am trying to give the board a kind of "texture".
What I did was I created this very small image (really small, be sure to look carefully):
And I passed this image to the UIColor.init(patternImage:) initializer to create a UIColor that is this image. I used this UIColor to fill some square UIBezierPaths, and the result looks like this:
All copies of that image lines up perfectly and they form many diagonal straight lines. So far so good.
Now on the iPad, the squares that I draw will be larger, and the borders of those squares will be larger too. I have successfully calculated what the stroke width and size of the squares should be, so that is not a problem.
However, since the squares are larger on an iPad, there will be more diagonal lines per square. I do not want that. I need to resize the very small image to a bigger one, and that the size depends on the stroke width of the squares. Specifically, the width of the resized image should be twice as much as the stroke width.
I wrote this extension to resize the image, adapted from this post:
extension UIImage {
func resized(toWidth newWidth: CGFloat) -> UIImage {
let scale = newWidth / size.width
let newHeight = size.height * scale
UIGraphicsBeginImageContextWithOptions(CGSize(width: newWidth, height: newHeight), false, 0)
self.draw(in: CGRect(x: 0, y: 0, width: newWidth, height: newHeight))
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage!
}
}
And called it like this:
// this is the code I used to draw a single square
let path = UIBezierPath(rect: CGRect(origin: point(for: Position(x, y)), size: CGSize(width: squareLength, height: squareLength)))
UIColor.black.setStroke()
path.lineWidth = strokeWidth
// this is the line that's important!
UIColor(patternImage: #imageLiteral(resourceName:
"texture").resized(toWidth: strokeWidth * 2)).setFill()
path.fill()
path.stroke()
Now the game board looks like this on an iPhone:
You might need to zoom in the webpage a bit to see what I mean. The board now looks extremely ugly. You can see the "borders" of each copy of the image. I don't want this. On an iPad though, the board looks fine. I suspect that this only happens when I downsize the image.
I figured that this might be due to the antialiasing that happens when I use the extension. I found this post and this post about removing antialiasing, but the former seems to be doing this in a image view while I am doing this in the draw(_:) method of my custom GameBoardView. The latter's solution seems to be exactly the same as what I am using.
How can I resize without antialiasing? Or on a higher level of abstraction, How can I make my board look pretty?
class Ruled: UIView {
override func draw(_ rect: CGRect) {
let T: CGFloat = 15 // desired thickness of lines
let G: CGFloat = 30 // desired gap between lines
let W = rect.size.width
let H = rect.size.height
guard let c = UIGraphicsGetCurrentContext() else { return }
c.setStrokeColor(UIColor.orange.cgColor)
c.setLineWidth(T)
var p = -(W > H ? W : H) - T
while p <= W {
c.move( to: CGPoint(x: p-T, y: -T) )
c.addLine( to: CGPoint(x: p+T+H, y: T+H) )
c.strokePath()
p += G + T + T
}
}
}
Enjoy.
Note that you would, obviously, clip that view.
If you want to have a number of them on the screen or in a pattern, just do that.
To clip to a given rectangle:
The class above simply draws it the "size of the UIView".
However, often, you want to draw a number of the "boxes" actually within the view, at different coordinates. (A good example is for a calendar).
Furthermore, this example explicitly draws "both stripes" rather than drawing one stripe over the background color:
func simpleStripes(x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat) {
let stripeWidth: CGFloat = 20.0 // whatever you want
let m = stripeWidth / 2.0
guard let c = UIGraphicsGetCurrentContext() else { return }
c.setLineWidth(stripeWidth)
let r = CGRect(x: x, y: y, width: width, height: height)
let longerSide = width > height ? width : height
c.saveGState()
c.clip(to: r)
var p = x - longerSide
while p <= x + width {
c.setStrokeColor(pale blue)
c.move( to: CGPoint(x: p-m, y: y-m) )
c.addLine( to: CGPoint(x: p+m+height, y: y+m+height) )
c.strokePath()
p += stripeWidth
c.setStrokeColor(pale gray)
c.move( to: CGPoint(x: p-m, y: y-m) )
c.addLine( to: CGPoint(x: p+m+height, y: y+m+height) )
c.strokePath()
p += stripeWidth
}
c.restoreGState()
}
extension UIImage {
func ResizeImage(targetSize: CGSize) -> UIImage
{
let size = self.size
let widthRatio = targetSize.width / self.size.width
let heightRatio = targetSize.height / self.size.height
// Figure out what our orientation is, and use that to form the rectangle
var newSize: CGSize
if(widthRatio > heightRatio) {
newSize = CGSize(width: size.width * heightRatio, height: size.height * heightRatio)
} else {
newSize = CGSize(width: size.width * widthRatio, height: size.height * widthRatio)
}
// This is the rect that we've calculated out and this is what is actually used below
let rect = CGRect(x: 0, y: 0, width: newSize.width,height: newSize.height)
// Actually do the resizing to the rect using the ImageContext stuff
UIGraphicsBeginImageContextWithOptions(newSize, false, 1.0)
self.draw(in: rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage!
}
}
The code is added to Github to let you understand the real problem.
This is the hierarchy:
-- ViewController.View P [width: 375, height: 667]
---- UIImageView A [width: 375, height: 667] Name: imgBackground
[A is holding an image of size(1287,1662)]
---- UIImageView B [width: 100, height: 100] Name: imgForeground
[B is holding an image of size(2400,982)]
I am trying to merge A with B but the result is stretched.
This is the merge code:
func mixImagesWith(frontImage:UIImage?, backgroundImage: UIImage?, atPoint point:CGPoint, ofSize signatureSize:CGSize) -> UIImage {
let size = self.imgBackground.frame.size
UIGraphicsBeginImageContextWithOptions(size, false, UIScreen.main.scale)
backgroundImage?.draw(in: CGRect.init(x: 0, y: 0, width: size.width, height: size.height))
frontImage?.draw(in: CGRect.init(x: point.x, y: point.y, width: signatureSize.width, height: signatureSize.height))
let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return newImage
}
Note:
.contentMode = .scaleAspectFit
Code works but the result is stretched.
See this line in code, let size = self.imgBackground.frame.size – I need to change this to fix the problem. Find the origin of subview with respect to UIImage size
Here's the screenshot to understand the problem:
What should I do to get the proper output of merge function?
You have two bugs in your code:
You should also calculate aspect for document image to fit it into UIImageView. In mergeImages() replace:
img.draw(in: CGRect(x: 0, y: 0, width: size.width, height: size.height))
with:
img.draw(in: getAspectFitFrame(sizeImgView: size, sizeImage: img.size))
When calculating aspect you center image horizontally/vertically if its width/height less then UIImageView width/height. But instead of comparing newWidth and newHeight you should compare factors:
if hfactor > vfactor {
y = (sizeImgView.height - newHeight) / 2
} else {
x = (sizeImgView.width - newWidth) / 2
}
Try bellow code it works for me, hope it works for you too,
func addWaterMarkToImage(img:UIImage, sizeWaterMark:CGRect, waterMarkImage:UIImage, completion : ((UIImage)->())?){
handler = completion
let img2:UIImage = waterMarkImage
let rect = CGRect(x: 0, y: 0, width: img.size.width, height: img.size.height)
UIGraphicsBeginImageContext(img.size)
img.draw(in: rect)
let frameAspect:CGRect = getAspectFitFrame(sizeImgView: sizeWaterMark.size, sizeImage: waterMarkImage.size)
let frameOrig:CGRect = CGRect(x: sizeWaterMark.origin.x+frameAspect.origin.x, y: sizeWaterMark.origin.y+frameAspect.origin.y, width: frameAspect.size.width, height: frameAspect.size.height)
img2.draw(in: frameOrig, blendMode: .normal, alpha: 1)
let result = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
if handler != nil {
handler!(result!)
}
}
//MARK - Get Aspect Fit frame of UIImage
func getAspectFitFrame(sizeImgView:CGSize, sizeImage:CGSize) -> CGRect{
let imageSize:CGSize = sizeImage
let viewSize:CGSize = sizeImgView
let hfactor : CGFloat = imageSize.width/viewSize.width
let vfactor : CGFloat = imageSize.height/viewSize.height
let factor : CGFloat = max(hfactor, vfactor)
// Divide the size by the greater of the vertical or horizontal shrinkage factor
let newWidth : CGFloat = imageSize.width / factor
let newHeight : CGFloat = imageSize.height / factor
var x:CGFloat = 0.0
var y:CGFloat = 0.0
if newWidth > newHeight{
y = (sizeImgView.height - newHeight)/2
}
if newHeight > newWidth{
x = (sizeImgView.width - newWidth)/2
}
let newRect:CGRect = CGRect(x: x, y: y, width: newWidth, height: newHeight)
return newRect
}
I tried to draw scaleAspectFill like contents mode.
I found how to make sacelAspectFit using AVFoundation But I can't find scaleAspectFill.
if I draw horizontal image, I don't know x value
image.draw(in: CGRect(origin: CGPoint.init(x: ?, y: 0), size: CGSize(width: displayWidth*(image.size.width/image.size.height), height: displayWidth)))
Assuming you have an image called image, and you want to draw it inside a rectangle targetRect so that it fills the rect without being distorted, you can use the following code:
let aspect = image.size.width / image.size.height
let rect: CGRect
if targetRect.size.width / aspect > targetRect.size.height {
let height = targetRect.size.width / aspect
rect = CGRect(x: 0, y: (targetRect.size.height - height) / 2,
width: targetRect.size.width, height: height)
} else {
let width = targetRect.size.height * aspect
rect = CGRect(x: (targetRect.size.width - width) / 2, y: 0,
width: width, height: targetRect.size.height)
}
image.draw(in: rect)
Note: this doesn't clip the image, so it will draw outside the edges of the target rect. if you want to clip the image, call CGContextClipToRect(context, rect) before drawing.
Note also that the core graphics vertical axis is flipped, with zero starting in the bottom-left instead of top-left compared to UIGraphics, so you may need to flip the rect and clipping rect accordingly.
I'm attempting to combine both an image and a text field into a single image whilst still keeping the texts initial positioning.
I'm using UIGraphicsBeginImageContext to create a bitmap context and UIGraphicsGetImageFromCurrentImageContext to draw the final image.
So far, I have the following contained within a function:
let size = CGSize(width: self.takenImage.size.width, height: self.takenImage.size.height)
UIGraphicsBeginImageContextWithOptions(takenImage.size, false, takenImage.scale)
let areaSize = CGRect(x: 0, y: 0, width: self.takenImage.size.width, height: self.takenImage.size.height)
takenImage.draw(in: areaSize)
let imageViewSize = self.takenImage.size
let multiWidth = areaSize.width / imageViewSize.width
let multiHeight = areaSize.height / imageViewSize.height
print ("multiWidth = \(multiWidth)")
print ("multiHeight = \(multiHeight)")
let textSize = CGRect(x: textOverlay.frame.origin.x * multiWidth, y: textOverlay.frame.origin.y * multiHeight, width: textOverlay.frame.size.width * multiWidth, height: textOverlay.frame.size.height * multiHeight)
textOverlay.drawText(in: textSize)
let outputImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
self.finalImage = outputImage
takenImage is the taken image from my camera (never null) and textOverlay is a UITextField containing the wanted text.
I first create the bitmap and draw takenImage using both its original width/height.
If I draw just this to my finalImage, all works fine. The problem stems from trying to add the text and keep it in the same position.
I've tried to create a second CGRect with x, y, w, h coordinates from the UITextField : textOverlay but when viewing the final image, I'm getting weird results.
The images can be seen here.
How would I go about preserving the text's position in the merged image?
you need recalculate area size to draw text.
let areaSize = CGRect(x: 0, y: 0, width: self.takenImage.size.width, height: self.takenImage.size.height)
takenImage.draw(in: areaSize)
let imageViewSize = self.imageView.size
let multiWidth = areaSize.width / imageViewSize.width
let multiHeight = areaSize.height / imageViewSize.height
let textSize = CGRect(x: textOverlay.frame.origin.x * multiWidth, y: textOverlay.frame.origin.y * multiHeight, width: textOverlay.frame.size.width * multiWidth, height: textOverlay.frame.size.height * multiHeight)
textOverlay.drawText(in: textSize)
Here, I use self.imageView - it is imageView contains your takenImage.
Hope it help.