NEW: Learn SwiftUI with my free YouTube video series! >>

How to find the scale from a CGAffineTransform

Swift version: 5.0

Paul Hudson    @twostraws   

If you have a CGAffineTransform and want to know what its scale component is – regardless of whether it has been rotated or translated – use this code:

func scale(from transform: CGAffineTransform) -> Double {
    return sqrt(Double(transform.a * transform.a + transform.c * transform.c))
}

LEARN SWIFTUI FOR FREE I wrote a massive, free SwiftUI tutorial collection, and also have a growing list of free SwiftUI tutorials on YouTube – get started today!

Available from iOS 2.0

Did this solution work for you? Please pass it on!

Other people are reading…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

MASTER SWIFT NOW
Buy Testing Swift Buy Practical iOS 12 Buy Pro Swift Buy Swift Design Patterns Buy Swift Coding Challenges Buy Server-Side Swift (Vapor Edition) Buy Server-Side Swift (Kitura Edition) Buy Hacking with macOS Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with Swift Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let me know!

Average rating: 5.0/5

Click here to visit the Hacking with Swift store >>