Create a basic AR object using ARKit and SCNKit

ARBasicObject.swift

//  Creating a simple Augmented Reality object with ARKit and SceneKit is surprisingly easy! But before you get started, you
//  need to add a key-value pair to your application's Info.plist (Information Property List) file. Add the key "Privacy -
//  Camera Usage Description" with the corresponding value "This application will use your camera for Augmented Reality", or
//  some similarly descriptive note.

//  Let's get started!

//  You'll need to import SceneKit to create your object and ARKit to place it in your augmented reality space.
import UIKit
import SceneKit
import ARKit

//  Make sure you conform to the ARSCNView Delegate.
class ARBasicObjectViewController: UIViewController, ARSCNViewDelegate {
    
//  Declare an ARSCNView  
    var sceneView: ARSCNView!

    override func viewDidLoad() {
        super.viewDidLoad()

    //  Set the view frame to match the bounds of your view controller, and add the sceneView as a subview to your view 
    //  controller's view.
        self.sceneView = ARSCNView(frame: self.view.frame)
        self.view.addSubview(self.sceneView)
        
    //  Assign the sceneView's delegate to itself, and optionally display statistics at the bottom of the view.
        sceneView.delegate = self
        sceneView.showsStatistics = true
        
    //  Create an SCNScene object to be used later and create an SCNBox. This box will be the 3D object that will be
    //  displayed. Note that the dimensions of the box are in meters, so choose appropriate values depending on your
    //  goals. Also, chamfer refers to an object's right-angled edge. The chamferRadius parameter is similar to editing
    //  the corner radius of two dimensional views in Swift; it determines how rounded (if at all) the edges of the box are.
        let scene = SCNScene()
        let box = SCNBox(width: 0.2, height: 0.2, length: 0.2, chamferRadius: 0.01)
        
    //  Create an SCNMaterial object, and use the diffuse.contents property to give the box some color. You can also
    //  assign static images to diffuse.contents. You can see that example when we explore an AR space with multiple 
    //  objects.
        let material = SCNMaterial()
        material.diffuse.contents = UIColor.green
        
    //  Now create an SCNNode. Assign the box to the node's geometry property, and assign the materials to the
    //  geometry.materials property. Assign an SCNVector3 to the node's position property. Note that the parameters for the
    //  vector are in meters, so select appropriate values. Also note that a positive value for the z-coordinate will place
    //  the object behind you.
        let node = SCNNode()
        node.geometry = box
        node.geometry?.materials = [material]
        node.position = SCNVector3(x: 0, y: 0.1, z: -0.5)
        
    //  Add the node as a child node to the root node's childNodes array
        scene.rootNode.addChildNode(node)
        
    //  Assign the scene to the scene property of the sceneView. Say that five times fast!
        sceneView.scene = scene
        
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        
    //  Allow your device to track the world around a device.. This class uses the rear camera and track's a device's
    //  position and orientation and detects flat surfaces in the real world.
    //  See https://developer.apple.com/documentation/arkit/arworldtrackingconfiguration for more details.
        let configuration = ARWorldTrackingConfiguration()        
        
    //  Run the sceneView's session with the configuration you just declared.
        sceneView.session.run(configuration)
    }
    
    override func viewWillDisappear(_ animated: Bool) {
        super.viewWillDisappear(animated)
        
    //  Pause the sceneView's session when the user is not making use of the AR view. This allows the device to avoid using
    //  computationally expensive AR rendering.
        sceneView.session.pause()
    }

}