I’m working currently on a project where you can load your usdz file into a Realitiykit. I’m relatively new to this API. What I want,is to have a preview of a usdz object and being able to selct some surface points of this object and to connect those via a line. In order to achive that i have some problems:

1. Firstly, how do I load an object in a plane white view (Not added into the real world camera AR)
2. Secondly, how am I able to select some points on the 3D object surface via gesture recogintion.
3. How do I connect those with a line.

This is my current code:

struct ContentView: View {
    var body: some View {
        ARViewContainer()
            .edgesIgnoringSafeArea(.all)
    }
}

struct ARViewContainer: UIViewRepresentable {
    func makeUIView(context: Context) -> ARView {
        let arView = ARView(frame: .zero)
        context.coordinator.arView = arView
        
        // Load the USDZ model
        let modelEntity = try! ModelEntity.loadModel(named: "yourModel.usdz")
        
        // Create an anchor to hold the model
        let anchorEntity = AnchorEntity(world: [0, 0, 0])
        anchorEntity.addChild(modelEntity)
        
        // Add the anchor to the ARView
        arView.scene.addAnchor(anchorEntity)
        
        // Configure the background color to white (simulates a plane white view)
        arView.environment.background = .color(.white)
        
        // Setup gesture recognizer
        context.coordinator.setupGestureRecognition()
        
        return arView
    }
    
    func updateUIView(_ uiView: ARView, context: Context) {}
    
    func makeCoordinator() -> Coordinator {
        return Coordinator()
    }
}

class Coordinator: NSObject {
    var arView: ARView?
    var selectedPoints: [SIMD3<Float>] = []
    
    override init() {
        super.init()
    }
    
    func setupGestureRecognition() {
        guard let arView = arView else { return }
        let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(_:)))
        arView.addGestureRecognizer(tapGesture)
    }
    
    @objc private func handleTap(_ gesture: UITapGestureRecognizer) {
        guard let arView = arView else { return }
        let location = gesture.location(in: arView)
        
        // Perform a hit test to find where the user tapped on the model
        let results = arView.hitTest(location)
        
        if let firstResult = results.first {
            let position = firstResult.worldTransform.translation
            selectedPoints.append(position)
            addSphere(at: position)
            
            if selectedPoints.count > 1 {
                drawLine(from: selectedPoints[selectedPoints.count - 2], to: position)
            }
        }
    }
    
    private func addSphere(at position: SIMD3<Float>) {
        guard let arView = arView else { return }
        
        let sphere = MeshResource.generateSphere(radius: 0.01)
        let material = SimpleMaterial(color: .red, isMetallic: false)
        let sphereEntity = ModelEntity(mesh: sphere, materials: [material])
        sphereEntity.position = position
        
        let anchorEntity = AnchorEntity(world: position)
        anchorEntity.addChild(sphereEntity)
        arView.scene.addAnchor(anchorEntity)
    }
    
    private func drawLine(from start: SIMD3<Float>, to end: SIMD3<Float>) {
        guard let arView = arView else { return }
        
        let vertices: [SIMD3<Float>] = [start, end]
        let indices: [UInt32] = [0, 1]
        let lineMesh = MeshResource.generate(from: vertices, indices: indices)
        
        let material = SimpleMaterial(color: .blue, isMetallic: false)
        let lineEntity = ModelEntity(mesh: lineMesh, materials: [material])
        
        let anchorEntity = AnchorEntity(world: [0, 0, 0])
        anchorEntity.addChild(lineEntity)
        arView.scene.addAnchor(anchorEntity)
    }
}

extension matrix_float4x4 {
    /// Extracts the translation vector (position) from the 4x4 matrix
    var translation: SIMD3<Float> {
        return SIMD3<Float>(columns.3.x, columns.3.y, columns.3.z)
    }
}

I appriciate your time!