(SceneKit) How to the the image in the center of the SCNScene (dynamically)? (NOT SPRITEKIT)

I need to set the image in the center of the SCNScene in order to do this I use such an approach

...
        let image = UIImage(named: "my_image")
        let scene = SCNScene()
        scene.background.contents = image
...

but the image I get is stretched in order to fill the entire screen, what I need is just to set it center.

I tried different approaches, but without luck.

For example, create such an extension was the last attempt

extension SCNScene {
    func addBackground(imageName: String = "YOUR DEFAULT IMAGE NAME", contentMode: UIView.ContentMode = .scaleToFill) {
        // setup the UIImageView
        let backgroundImageView = UIImageView(frame: UIScreen.main.bounds)
        backgroundImageView.image = UIImage(named: imageName)
        backgroundImageView.contentMode = contentMode
        backgroundImageView.translatesAutoresizingMaskIntoConstraints = false

        // adding NSLayoutConstraints
        let leadingConstraint = NSLayoutConstraint(item: backgroundImageView, attribute: .leading, relatedBy: .equal, toItem: self, attribute: .leading, multiplier: 1.0, constant: 0.0)
        let trailingConstraint = NSLayoutConstraint(item: backgroundImageView, attribute: .trailing, relatedBy: .equal, toItem: self, attribute: .trailing, multiplier: 1.0, constant: 0.0)
        let topConstraint = NSLayoutConstraint(item: backgroundImageView, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 0.0)
        let bottomConstraint = NSLayoutConstraint(item: backgroundImageView, attribute: .bottom, relatedBy: .equal, toItem: self, attribute: .bottom, multiplier: 1.0, constant: 0.0)

self.background.contents = backgroundImageView

        NSLayoutConstraint.activate([leadingConstraint, trailingConstraint, topConstraint, bottomConstraint])
    }
}

UPD

Actual result is

desired result is