Drawing rotated text with NSString drawInRect

Question

I found this answer on how to draw rotated text with NSString drawInRect:, but I\'m not sure how it works since it only sort of works for me: https://discussions.apple.com/t

Answer 1

Here'a an updated and simplified version of KoNEW's answer. It preserves the state of the graphics context as a bonus. This is also a simple function instead of a String extension.

func drawRotatedText(_ text: String, at p: CGPoint, angle: CGFloat, font: UIFont, color: UIColor) {
  // Draw text centered on the point, rotated by an angle in degrees moving clockwise.
  let attrs = [NSFontAttributeName: font, NSForegroundColorAttributeName: color]
  let textSize = text.size(attributes: attrs)
  let c = UIGraphicsGetCurrentContext()!
  c.saveGState()
  // Translate the origin to the drawing location and rotate the coordinate system.
  c.translateBy(x: p.x, y: p.y)
  c.rotate(by: angle * .pi / 180)
  // Draw the text centered at the point.
  text.draw(at: CGPoint(x: -textSize.width / 2, y: -textSize.height / 2), withAttributes: attrs)
  // Restore the original coordinate system.
  c.restoreGState()
}