ViewController_001.swift

import UIKit
import ARKit

class ViewController: UIViewController, ARSCNViewDelegate {

    @IBOutlet var sceneView: ARSCNView!
    
    private var viewportSize: CGSize!
    
    override var shouldAutorotate: Bool { return false }

    override func viewDidLoad() {
        super.viewDidLoad()
        sceneView.delegate = self
        
        viewportSize = sceneView.frame.size
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        let configuration = ARWorldTrackingConfiguration()
        configuration.planeDetection = []
        sceneView.session.run(configuration)
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        sceneView.session.pause()
    }
}