How to draw vertical text on CGContext? - ios

Question

I want to draw a vertical text. I had tried different way to rotate string using rotate by but its not working
Here is my code
override func draw(with box: PDFDisplayBox, to context: CGContext) {
let name = "Sunny"
// Draw original content
super.draw(with: box, to: context)
// Draw rotated overlay string
UIGraphicsPushContext(context)
context.saveGState()
let pageBounds = self.bounds(for: box)
context.translateBy(x: pageBounds.size.width, y: 0)
context.scaleBy(x: -1.0, y: -1.0)
context.rotate(by: CGFloat.pi / 4.0)
let string: NSString = name as! NSString
let attributes = [
NSAttributedString.Key.foregroundColor: UIColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 0.5),
NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 64)
]
string.draw(at: CGPoint(x:250, y:40), withAttributes: attributes)
context.restoreGState()
UIGraphicsPopContext()
}
How can i draw?

Answer 1

We can draw the vertical string using the below code, in which I have converted given string by adding line separators between the characters.
override func draw(with box: PDFDisplayBox, to context: CGContext) {
// Draw original content
super.draw(with: box, to: context)
// Draw rotated overlay string
UIGraphicsPushContext(context)
context.saveGState()
let pageBounds = self.bounds(for: box)
context.translateBy(x: 0.0, y: pageBounds.size.height)
context.scaleBy(x: 1.0, y: -1.0)
context.rotate(by: CGFloat.pi / -60.0)
// Convert string by adding line separators.
let string = "Sunny".trimmingCharacters(in: .whitespaces)
let asArray = Array(string)
let verticalString = asArray.map { "\($0)" }.joined(separator: "\n")
let attributes: [NSAttributedString.Key: Any] = [
NSAttributedString.Key.foregroundColor: #colorLiteral(red: 0.4980392157, green: 0.4980392157, blue: 0.4980392157, alpha: 0.5),
NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 64)
]
verticalString.draw(at: CGPoint(x: 250, y: 40), withAttributes: attributes)
context.restoreGState()
UIGraphicsPopContext()
}
Output of vertical string in PDF