Turn occlusion on for ARFaceTrackingConfiguration - swift

Question

I am trying to follow the steps to create this following this article (image below from article):
It is basically recognising a face to put something on the face (a tattoo) and placing a background image behind it.
I am using an iPhone X device to test the code, but every time I test if .personSegmentation is supported, it is false:
if ARFaceTrackingConfiguration.supportsFrameSemantics(.personSegmentation) {
configuration.frameSemantics.insert(.personSegmentation) // code never executed.
}
My whole code for adding the plane to put on top of the face plus the background is:
The ARSCNViewDelegate delegate to add the nodes:
private var virtualBackgroundNode = SCNNode()
func renderer(_ renderer: SCNSceneRenderer, nodeFor anchor: ARAnchor) -> SCNNode? {
guard let device = sceneView.device else {
return nil
}
let faceGeometry = ARSCNFaceGeometry(device: device)
let faceNode = SCNNode(geometry: faceGeometry)
faceNode.geometry?.firstMaterial?.transparency = 0
let tattooPlane = SCNPlane(width: 0.13, height: 0.06)
tattooPlane.firstMaterial?.diffuse.contents = UIImage(named: "Tattoos/tattoo0")!
tattooPlane.firstMaterial?.isDoubleSided = true
let tattooNode = SCNNode()
tattooNode.position.z = faceNode.boundingBox.max.z * 3 / 4
tattooNode.position.y = 0.027
tattooNode.geometry = tattooPlane
faceNode.addChildNode(tattooNode)
configureBackgroundView()
sceneView.scene.rootNode.addChildNode(virtualBackgroundNode)
return faceNode
}
Resizing the background image, setting it and positioning the background node:
func configureBackgroundView() {
let (skScene, mediaAspectRatio) = makeImageBackgroundScene(image: UIImage(named: "Cats/cat0")!)
let size = skScene.size
virtualBackgroundNode.geometry = SCNGeometry.Plane(width: size.width, height: size.height)
let material = SCNMaterial()
material.diffuse.contents = skScene
virtualBackgroundNode.geometry?.materials = [material]
virtualBackgroundNode.scale = SCNVector3(1.7 * mediaAspectRatio, 1.7, 1)
let cameraPosition = sceneView.pointOfView?.scale
let position = SCNVector3(cameraPosition!.x, cameraPosition!.y, cameraPosition!.z - 1000)
virtualBackgroundNode.position = position
}
This method creates a SpriteKit image by resizing the original asset:
func makeImageBackgroundScene(image: UIImage) -> (scene: SKScene, mediaAspectRatio: Double) {
//Adjusted so that the aspect ratio of the image is not distorted
let width = image.size.width
let height = image.size.height
let mediaAspectRatio = Double(width / height)
let cgImage = image.cgImage!
let newImage = UIImage(cgImage: cgImage, scale: 1.0, orientation: .up)
let skScene = SKScene(size: CGSize(width: 1000 * mediaAspectRatio, height: 1000))
let texture = SKTexture(image: newImage)
let skNode = SKSpriteNode(texture:texture)
skNode.position = CGPoint(x: skScene.size.width / 2.0, y: skScene.size.height / 2.0)
skNode.size = skScene.size
skNode.yScale = -1.0
skScene.addChild(skNode)
return (skScene, mediaAspectRatio)
}
Any advice on what to try? Snapchat and TikTok have similar Face recognition + background setups and they work in my device.
Thanks for any help.