A horizontal plane ARkit iOS 11.4 Swift 4 detector

ViewController.swift

//  Created by Oscar De la Hera Gomez on 8/13/18.
//  Copyright © 2018 Delasign. All rights reserved.
//

import UIKit
import SceneKit
import ARKit

class ViewController: UIViewController, ARSCNViewDelegate {

    @IBOutlet var sceneView: ARSCNView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Set the view's delegate
        sceneView.delegate = self
        
        // Show statistics such as fps and timing information
        sceneView.showsStatistics = true
        
        sceneView.debugOptions = [ARSCNDebugOptions.showFeaturePoints];
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
        // Create a session configuration
        let configuration = ARWorldTrackingConfiguration()
        configuration.planeDetection = .horizontal;

        // Run the view's session
        sceneView.session.run(configuration)
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        
        // Pause the view's session
        sceneView.session.pause()
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Release any cached data, images, etc that aren't in use.
    }

    // MARK: - ARSCNViewDelegate
    
/*
    // Override to create and configure nodes for anchors added to the view's session.
    func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {
        let node = SCNNode()
     
        return node
    }
*/
    
    func session(_ session: ARSession, didFailWithError error: Error) {
        // Present an error message to the user
        
    }
    
    func sessionWasInterrupted(_ session: ARSession) {
        // Inform the user that the session has been interrupted, for example, by presenting an overlay
        
    }
    
    func sessionInterruptionEnded(_ session: ARSession) {
        // Reset tracking and/or remove existing anchors if consistent tracking is required
        
    }
    
    
    // MARK : ARKIT RENDERER
    
    func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
        
        // 1
        guard let planeAnchor = anchor as? ARPlaneAnchor else { return }
        
        // 2
        let width = CGFloat(planeAnchor.extent.x)
        let height = CGFloat(planeAnchor.extent.z)
        let plane = SCNPlane(width: width, height: height)
        
        // 3
        plane.materials.first?.diffuse.contents = UIColor.white.withAlphaComponent(0.5);
        
        // 4
        let planeNode = SCNNode(geometry: plane)
        
        // 5
        let x = CGFloat(planeAnchor.center.x)
        let y = CGFloat(planeAnchor.center.y)
        let z = CGFloat(planeAnchor.center.z)
        planeNode.position = SCNVector3(x,y,z)
        planeNode.eulerAngles.x = -.pi / 2
        
        // 6
        node.addChildNode(planeNode)
    }
    
    func renderer(_ renderer: SCNSceneRenderer, didUpdate node: SCNNode, for anchor: ARAnchor) {
        
        // 1
        guard let planeAnchor = anchor as?  ARPlaneAnchor,
            let planeNode = node.childNodes.first,
            let plane = planeNode.geometry as? SCNPlane
            else { return }
        
        // 2
        let width = CGFloat(planeAnchor.extent.x)
        let height = CGFloat(planeAnchor.extent.z)
        plane.width = width
        plane.height = height
        
        // 3
        let x = CGFloat(planeAnchor.center.x)
        let y = CGFloat(planeAnchor.center.y)
        let z = CGFloat(planeAnchor.center.z)
        planeNode.position = SCNVector3(x, y, z)
    }
}