Getting the Display P3 values back out of a UIColor created with init(displayP3Red:green:blue:alpha:)

Color.swift

import UIKit

// Create color using P3 color space
let linearColor = UIColor(displayP3Red: 1, green: 0.5, blue: 0.2, alpha: 1)

do {
    var r: CGFloat = 0, g: CGFloat = 0, b: CGFloat = 0, a: CGFloat = 0
    linearColor.getRed(&r, green: &g, blue: &b, alpha: &a)
    print(r, g, b, a) // 1.07, 0.46, 0.0, 1.0 - not the expected values
}

// Convert to P3
let p3Color: UIColor = {
    guard let colorSpace = CGColorSpace(name: CGColorSpace.displayP3),
          let cgColor = linearColor.cgColor.converted(
            to: colorSpace,
            intent: .defaultIntent,
            options: nil
          ),
          let rgba = cgColor.components,
          rgba.count == 4
    else {
        return linearColor
    }
    // FWIW, I could actually just use these component values directly instead
    // of converting back to a UIColor to extract them again
    return UIColor(red: rgba[0], green: rgba[1], blue: rgba[2], alpha: rgba[3])
}()

do {
    var r: CGFloat = 0, g: CGFloat = 0, b: CGFloat = 0, a: CGFloat = 0
    p3Color.getRed(&r, green: &g, blue: &b, alpha: &a)
    print(r, g, b, a) // 1.0, 0.5, 0.2, 1.0 - matches the input values
}

This was just what I was looking for, thanks for posting it!

@mneuburg-livefront you're very welcome!

(You aren't by any chance the same Matt Neuburg that authored multiple iOS development books are you? If so it was one of your books that first got me into iOS development ~15 years ago, so I'm doubly happy to return the favor!)

👍 😸