ARKit Image Detection and Add Image From Assets.xcassets - swift

Question

I am playing around with the code I downloaded from Apple Developer site on AR Image Detection. I am trying to modify it to show a specific image in the AR Resource folder in Resources/Assets.xcassets once an image is detected. I see a similar question was posted 2 years ago and I tried the one and only answer on it but have no success. Can anyone help? Thank-you!
import ARKit
import SceneKit
import UIKit
class ViewController: UIViewController, ARSCNViewDelegate {
#IBOutlet var sceneView: ARSCNView!
#IBOutlet weak var blurView: UIVisualEffectView!
/// The view controller that displays the status and "restart experience" UI.
lazy var statusViewController: StatusViewController = {
return children.lazy.compactMap({ $0 as? StatusViewController }).first!
}()
/// A serial queue for thread safety when modifying the SceneKit node graph.
let updateQueue = DispatchQueue(label: Bundle.main.bundleIdentifier! +
".serialSceneKitQueue")
/// Convenience accessor for the session owned by ARSCNView.
var session: ARSession {
return sceneView.session
}
// MARK: - View Controller Life Cycle
override func viewDidLoad() {
super.viewDidLoad()
sceneView.delegate = self
sceneView.session.delegate = self
// Hook up status view controller callback(s).
statusViewController.restartExperienceHandler = { [unowned self] in
self.restartExperience()
}
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
// Prevent the screen from being dimmed to avoid interuppting the AR experience.
UIApplication.shared.isIdleTimerDisabled = true
// Start the AR experience
resetTracking()
}
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
session.pause()
}
// MARK: - Session management (Image detection setup)
/// Prevents restarting the session while a restart is in progress.
var isRestartAvailable = true
/// Creates a new AR configuration to run on the `session`.
/// - Tag: ARReferenceImage-Loading
func resetTracking() {
guard let referenceImages = ARReferenceImage.referenceImages(inGroupNamed: "AR Resources", bundle: nil) else {
fatalError("Missing expected asset catalog resources.")
}
let configuration = ARWorldTrackingConfiguration()
configuration.detectionImages = referenceImages
session.run(configuration, options: [.resetTracking, .removeExistingAnchors])
statusViewController.scheduleMessage("Look around to detect images", inSeconds: 7.5, messageType: .contentPlacement)
}
// MARK: - ARSCNViewDelegate (Image detection results)
/// - Tag: ARImageAnchor-Visualizing
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
guard let imageAnchor = anchor as? ARImageAnchor else { return }
let referenceImage = imageAnchor.referenceImage
updateQueue.async {
// Create a plane to visualize the initial position of the detected image.
let plane = SCNPlane(width: referenceImage.physicalSize.width,
height: referenceImage.physicalSize.height)
let planeNode = SCNNode(geometry: plane)
planeNode.opacity = 0.25
/*
`SCNPlane` is vertically oriented in its local coordinate space, but
`ARImageAnchor` assumes the image is horizontal in its local space, so
rotate the plane to match.
*/
planeNode.eulerAngles.x = -.pi / 2
/*
Image anchors are not tracked after initial detection, so create an
animation that limits the duration for which the plane visualization appears.
*/
planeNode.runAction(self.imageHighlightAction)
plane.materials = [SCNMaterial()]
plane.materials[0].diffuse.contents = UIImage(named: "Macbook 12-inch")
// Add the plane visualization to the scene.
node.addChildNode(planeNode)
DispatchQueue.main.async {
let imageName = referenceImage.name ?? ""
self.statusViewController.cancelAllScheduledMessages()
self.statusViewController.showMessage("Detected image “\(imageName)”")
}
}
}
var imageHighlightAction: SCNAction {
return .sequence([
.wait(duration: 0.25),
.fadeOpacity(to: 0.85, duration: 0.25),
.fadeOpacity(to: 0.15, duration: 0.25),
.fadeOpacity(to: 0.85, duration: 0.25),
.fadeOut(duration: 0.5),
.removeFromParentNode()
])
}
}

Answer 1

In Xcode's Assets folder, click on + button and create a folder for reference images (use .png or .jpg formats). In Xcode's directories this folder will get .arresourcegroup extention.
// AR and Textures –> AR Resource Group
You can rename this folder. There's no need to put inside this folder Hi-Res images. Appropriate resolution for each image is 400x400. Put there not more than 100 images. That's all.
Your code may look like this:
guard let images = ARReferenceImage.referenceImages(
inGroupNamed: "AR Resources",
bundle: nil)
else { return }
let config = ARWorldTrackingConfiguration()
config.detectionImages = images
config.maximumNumberOfTrackedImages = 3
arView.session.run(config, options: [])