RealityKit – Which Entity is intersecting with other Entity - swift

Question

let height: Float = 1
let width: Float = 0.5
let box = MeshResource.generateBox(width: 0.02, height: height, depth: width)
This box will have a real-time position same as the current camera position, In AR World I would have multiple boxes with different shapes, I want to identify which object is intersecting with the current real-time box.
I can not do this with position matching (The nearest one). I literally want to know the object which is touching/intersecting the real-time box.
Thanks in advance.

Answer 1

You can easily do that using subscribe() method. The following code is a reference:
(physics for both objects was enabled in Reality Composer)
import UIKit
import RealityKit
import Combine
class ViewController: UIViewController {
#IBOutlet var arView: ARView!
var subscriptions: [Cancellable] = []
override func viewDidLoad() {
super.viewDidLoad()
let boxScene = try! Experience.loadBox()
arView.scene.anchors.append(boxScene)
let floorEntity = boxScene.children[0].children[1]
let subscribe = arView.scene.subscribe(to: CollisionEvents.Began.self,
on: floorEntity) { (event) in
print("Collision Occured")
print(event.entityA.name)
print(event.entityB.name)
}
self.subscriptions += [subscribe]
}
}