.swift

 override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        // Create a session configuration
        let configuration = ARImageTrackingConfiguration()
        
        guard let referenceImages = ARReferenceImage.referenceImages(inGroupNamed: "AR Resources", bundle: nil) else {
            fatalError("Missing expected asset catalog resources.")
        }
        
        configuration.trackingImages = referenceImages
      
        // Run the view's session
        sceneView.session.run(configuration)
    }