Disable 77% scaling for Mac Catalyst apps. (Swift)

OverrideCatalystScaleFactor.swift

let overrideCatalystScaleFactor: Void = {
    guard let sceneViewClass = NSClassFromString("UINSSceneView") as? NSObject.Type else {
        return
    }
    if sceneViewClass.instancesRespond(to: NSSelectorFromString("scaleFactor")) {
        // old
        swizzleInstanceMethod(
            class: sceneViewClass,
            originalSelector: NSSelectorFromString("scaleFactor"),
            swizzledSelector: #selector(swizzle_scaleFactor)
        )
    } else {
        // macOS 11.3 Beta 3+
        swizzleInstanceMethod(
            class: sceneViewClass,
            originalSelector: NSSelectorFromString("sceneToSceneViewScaleFactor"),
            swizzledSelector: #selector(swizzle_scaleFactor)
        )
        swizzleInstanceMethod(
            class: sceneViewClass,
            originalSelector: NSSelectorFromString("fixedSceneToSceneViewScaleFactor"),
            swizzledSelector: #selector(swizzle_scaleFactor2)
        )
        swizzleInstanceMethod(
            class: NSClassFromString("UINSSceneContainerView"),
            originalSelector: NSSelectorFromString("sceneToSceneViewScaleForLayout"),
            swizzledSelector: #selector(swizzle_scaleFactor3)
        )
    }
}()

@objc private extension NSObject {
    func swizzle_scaleFactor() -> CGFloat { 1 }
    func swizzle_scaleFactor2() -> CGFloat { 1 }
    func swizzle_scaleFactor3() -> CGFloat { 1 }
}

For implementation of swizzleInstanceMethod, check Swizzle.swift

Thanks works well overall but I have an issue:

When picking a photo using UIImagePickerController or PHPickerViewController the touches/clicks are not registered correctly. It's probably best to have the picker stick to the default 77% scaling. Any tips on how to do this?

@Janneman84 you could:
A. open those remote view controllers on a separated window scene, where scaling is set to 77% (requires modification on the swizzled methods);
or B. replace PHPickerViewController with a macOS equivalent such as UIDocumentPickerViewController or NSOpenPanel.

Thanks for the tip!

I figured out image pickers are pretty useless in MacOS anyway. A document picker works much better!