How to detect the 2D images using ARKit and RealityKit - swift

Question

I want to detect the 2D images using ARKit and RealityKit. I don't want to use SceneKit because many implementations based on RealityKit. I couldn't find any examples detecting images on RealityKit. I referred https://developer.apple.com/documentation/arkit/detecting_images_in_an_ar_experience sample code from apple. It uses Scenekit and ARSCNViewDelegate
let arConfiguration = ARWorldTrackingConfiguration()
arConfiguration.planeDetection = [.vertical, .horizontal]
arConfiguration.isLightEstimationEnabled = true
arConfiguration.environmentTexturing = .automatic
if let referenceImages = ARReferenceImage.referenceImages(inGroupNamed: "sanitzer", bundle: nil) {
arConfiguration.maximumNumberOfTrackedImages = 1
arConfiguration.detectionImages = referenceImages
}
self.session.run(arConfiguration, options: [.resetTracking, .removeExistingAnchors])
I have implemented ARSessionDelegate but not able to detect image?
func session(_ session: ARSession, didAdd anchors: [ARAnchor]) {
//how to capture image anchor?
}
func session(_ session: ARSession, didUpdate anchors: [ARAnchor]) {
//how to capture image anchor?
}
Apple has implemented ARSCNViewDelegate capture the detected images. What is the equivalent delegate for ARSCNViewDelegate in RealityKit? How to detect ARImageAnchor?

Answer 1

In ARKit/RealityKit project use the following code for session() instance methods:
import ARKit
import RealityKit
class ViewController: UIViewController, ARSessionDelegate {
func session(_ session: ARSession, didUpdate anchors: [ARAnchor]) {
guard let imageAnchor = anchors.first as? ARImageAnchor,
let _ = imageAnchor.referenceImage.name
else { return }
let anchor = AnchorEntity(anchor: imageAnchor)
// Add Model Entity to anchor
anchor.addChild(model)
arView.scene.anchors.append(anchor)
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
arView.session.delegate = self
resetTrackingConfig()
}
func resetTrackingConfig() {
guard let refImg = ARReferenceImage.referenceImages(inGroupNamed: "Sub",
bundle: nil)
else { return }
let config = ARWorldTrackingConfiguration()
config.detectionImages = refImg
config.maximumNumberOfTrackedImages = 1
let options = [ARSession.RunOptions.removeExistingAnchors,
ARSession.RunOptions.resetTracking]
arView.session.run(config, options: ARSession.RunOptions(options))
}
}
And take into consideration – a folder for reference images (in .png or .jpg format) must have an extension .arresourcegroup.