text draw on image extending off the image - ios

Question

I'm using the answer from SO POST to draw text on an image. The issue I am having is when the CGPoint is set near the right edge of the image, the text extends off of the image. I'm trying to figure out a way to draw left instead of right from the CGPoint or somehow calculate the size in points of the text that will be drawn then then move the draw point to accommodate for this size.
Here is the code I am using.
func textToImage(drawText text: NSString, inImage image: UIImage, atPoint point: CGPoint) -> UIImage {
let color = UserDefaults.standard.colorForKey(key: "color")!
let font = UserDefaults.standard.value(forKey: "font") as! String
let size = UserDefaults.standard.value(forKey: "size") as! Int
let fontAndSize = UIFont(name: font, size: CGFloat(size))!
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(image.size, false, scale)
let textFontAttributes = [
NSFontAttributeName: fontAndSize,
NSForegroundColorAttributeName: color,
] as [String : Any]
image.draw(in: CGRect(origin: CGPoint.zero, size: image.size))
let rect = CGRect(origin: point, size: image.size)
text.draw(in: rect, withAttributes: textFontAttributes)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage!
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if let mediaType = info[UIImagePickerControllerMediaType] as? String {
if mediaType.isEqual((kUTTypeImage as String)) {
if let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage {
let width = pickedImage.size.width
let height = pickedImage.size.height
// this puts the point in the bottom right of the image which then causes the text drawn to extend off of the image
let point = CGPoint(x: width - 20, y: height - 50)
let timestampText = getTimestampText() as NSString
let timestampImage = textToImage(drawText: timestampText, inImage: pickedImage, atPoint: point)
if newMedia {
UIImageWriteToSavedPhotosAlbum(timestampImage, nil, nil, nil)
}
}

Answer 1

If you want to draw to the left, you can in fact "calculate the size in points of the text that will be drawn then move the draw point to accommodate for this size" by using boundingRectWithSize:options:attributes:context:. Ex:
func textToImage(drawText text: NSString, inImage image: UIImage, atPoint point: CGPoint) -> UIImage {
let color = UserDefaults.standard.colorForKey(key: "color")!
let font = UserDefaults.standard.value(forKey: "font") as! String
let size = UserDefaults.standard.value(forKey: "size") as! Int
let fontAndSize = UIFont(name: font, size: CGFloat(size))!
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(image.size, false, scale)
let textFontAttributes = [
NSFontAttributeName: fontAndSize,
NSForegroundColorAttributeName: color,
] as [String : Any]
// Calculate text size
let rectSize = text.boundingRect(with: CGSize(width:CGFloat(MAXFLOAT), height: CGFloat(MAXFLOAT)), options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: textFontAttributes, context: nil).size
// Subtract the text width from the x origin
let rect = CGRect(x:point.x-rectSize.width, y:point.y, width:rectSize.width, height: rectSize.height)
text.draw(in: rect, withAttributes: textFontAttributes)
}

Answer 2

You can try aligning the text to the right using the NSParagraphStyleAttributeName
let textStyle = NSMutableParagraphStyle.defaultParagraphStyle().mutableCopy() as NSMutableParagraphStyle
textStyle.alignment = NSTextAlignment.rightTextAlignment
let textFontAttributes = [
NSFontAttributeName: fontAndSize,
NSForegroundColorAttributeName: color,
NSParagraphAttributeStyleName: textStyle
] as [String : Any]