NEW: Get your ticket to Hacking with Swift Live 2020! >>

How to find the scale from a CGAffineTransform

Swift version: 5.1

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 have a massive, free SwiftUI video collection on YouTube teaching you how to build complete apps with SwiftUI – check it out!

Listen to the Swift over Coffee podcast

Available from iOS 2.0

Similar solutions…

About the Swift Knowledge Base

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

BUY OUR BOOKS
Buy Pro Swift Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift (Vapor Edition) Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Server-Side Swift (Kitura Edition) Buy Beyond Code

Was this page useful? Let us know!

Average rating: 5.0/5