Does the SpriteView of an SKScene have layers? Unable to get magnifying glass view to work with scene.

I'm trying to make a magnifying glass that shows up when the user presses a button and follows the user's finger as it's dragged across the screen.

I came across a UIKit-based solution (https://github.com/niczyja/MagnifyingGlass-Swift), but when implemented in my SKScene, only the crosshairs are shown. Through experimentation I've found that magnifiedView?.layer.render(in: context) in:

   public override func draw(_ rect: CGRect) {
        guard let context = UIGraphicsGetCurrentContext() else { return }
        
        context.translateBy(x: radius, y: radius)
        context.scaleBy(x: scale, y: scale)
        context.translateBy(x: -magnifiedPoint.x, y: -magnifiedPoint.y)
        
        removeFromSuperview() 
        magnifiedView?.layer.render(in: context) 
        magnifiedView?.addSubview(self)
    }

can be removed without altering the situation, suggesting that line is not working as it should. But this is where I hit a brick wall. The view below is shown but not offset or magnified, and any attempt to add something to context results in a black magnifying glass.

Does anyone know why this is? I don't think it's an issue with the code, so I'm suspecting its something specific to SpriteKit or SKScene, likely related to how CALayers work.

Any pointers would be greatly appreciated.

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Full code below:

import UIKit
 
public class MagnifyingGlassView: UIView {
    public weak var magnifiedView: UIView? = nil {
        didSet {
            removeFromSuperview()
            magnifiedView?.addSubview(self)
        }
    }
    
    public var magnifiedPoint: CGPoint = .zero {
        didSet {
            center = .init(x: magnifiedPoint.x + offset.x, y: magnifiedPoint.y + offset.y)
        }
    }
    
    public var offset: CGPoint = .zero
    
    public var radius: CGFloat = 50 {
        didSet {
            frame = .init(origin: frame.origin, size: .init(width: radius * 2, height: radius * 2))
            layer.cornerRadius = radius
            crosshair.path = crosshairPath(for: radius)
        }
    }
    
    public var scale: CGFloat = 2
    
    public var borderColor: UIColor = .lightGray {
        didSet {
            layer.borderColor = borderColor.cgColor
        }
    }
    
    public var borderWidth: CGFloat = 3 {
        didSet {
            layer.borderWidth = borderWidth
        }
    }
    
    public var showsCrosshair = true {
        didSet {
            crosshair.isHidden = !showsCrosshair
        }
    }
    
    public var crosshairColor: UIColor = .lightGray {
        didSet {
            crosshair.strokeColor = crosshairColor.cgColor
        }
    }
    
    public var crosshairWidth: CGFloat = 5 {
        didSet {
            crosshair.lineWidth = crosshairWidth
        }
    }
    
    private let crosshair: CAShapeLayer = CAShapeLayer()
    
    public convenience init(offset: CGPoint = .zero, radius: CGFloat = 50, scale: CGFloat = 2, borderColor: UIColor = .lightGray, borderWidth: CGFloat = 3, showsCrosshair: Bool = true, crosshairColor: UIColor = .lightGray, crosshairWidth: CGFloat = 0.5) {
        self.init(frame: .zero)
        layer.masksToBounds = true
        layer.addSublayer(crosshair)
        
        defer {
            self.offset = offset
            self.radius = radius
            self.scale = scale
            self.borderColor = borderColor
            self.borderWidth = borderWidth
            self.showsCrosshair = showsCrosshair
            self.crosshairColor = crosshairColor
            self.crosshairWidth = crosshairWidth
        }
    }
    
    public func magnify(at point: CGPoint) {
        guard magnifiedView != nil else { return }
        magnifiedPoint = point
        layer.setNeedsDisplay()
    }
    
    private func crosshairPath(for radius: CGFloat) -> CGPath {
        let path = CGMutablePath()
        path.move(to: .init(x: radius, y: 0))
        path.addLine(to: .init(x: radius, y: bounds.height))
        path.move(to: .init(x: 0, y: radius))
        path.addLine(to: .init(x: bounds.width, y: radius))
        return path
    }
    
    public override func draw(_ rect: CGRect) {
        guard let context = UIGraphicsGetCurrentContext() else { return }
        
        context.translateBy(x: radius, y: radius)
        context.scaleBy(x: scale, y: scale)
        context.translateBy(x: -magnifiedPoint.x, y: -magnifiedPoint.y)
        
        removeFromSuperview() 
        magnifiedView?.layer.render(in: context) 
        //If above disabled, no change
        //Possible that nothing's being rendered into context
        //Could it be that SKScene view has no layer?
 
        magnifiedView?.addSubview(self)
    }
}