Pass value from SwiftUI to ARKit dynamically - swift

Question

I'm currently engaging personal project using ARKit with Swift.
In this app, a skeleton is appearing by detected body and it tracks body's motion.
What I want to know is, how to change the position of skeleton by touching a slider dynamically.
The position of skeleton is defined in ARKit class ARDelegateHandler such as self.characterOffset = [1, 0, 0] which means 1m right from a detected body.
I want to change the characterOffset's x-axis value by slider in SwiftUI.(something like self.characterOffset = [x, 0, 0])
Here is my code.
ARViewContainer.swift
import SwiftUI
import RealityKit
import ARKit
import Combine
struct ARViewContainer: UIViewRepresentable {
let characterAnchor = AnchorEntity()
#Binding var offsetValue:Float
#ObservedObject var offsetInstance = Offset()
func makeUIView(context: Context) -> ARView {
let arView = ARView(frame: .zero)
arView.session.delegate = context.coordinator
return arView
}
func updateUIView(_ uiView: ARView, context: Context) {
let configuration = ARBodyTrackingConfiguration()
uiView.session.run(configuration)
uiView.scene.addAnchor(characterAnchor)
print(offsetValue)
}
func makeCoordinator() -> ARDelegateHandler {
ARDelegateHandler(self, anchor: characterAnchor)
}
class ARDelegateHandler: NSObject, ARSessionDelegate {
var arVC: ARViewContainer
let characterAnchor: AnchorEntity
var character: BodyTrackedEntity?
var characterOffset: SIMD3<Float>
init(_ control: ARViewContainer, anchor: AnchorEntity) {
self.arVC = control
self.characterAnchor = anchor
self.characterOffset = [1, 0, 0]
super.init()
setSkeleton()
}
func setSkeleton(){
var cancellable: AnyCancellable? = nil
cancellable = Entity.loadBodyTrackedAsync(named: "character/robot").sink(
receiveCompletion: { completion in
if case let .failure(error) = completion {
print("Error: Unable to load model: \(error.localizedDescription)")
}
cancellable?.cancel()
}, receiveValue: { (character: Entity) in
if let character = character as? BodyTrackedEntity {
character.scale = [1, 1, 1]
self.character = character
cancellable?.cancel()
} else {
print("Error: Unable to load model as BodyTrackedEntity")
}
})
}
func session(_ session: ARSession, didUpdate anchors: [ARAnchor]) {
for anchor in anchors {
guard let bodyAnchor = anchor as? ARBodyAnchor else { continue }
let bodyPosition = simd_make_float3(bodyAnchor.transform.columns.3)
characterAnchor.position = bodyPosition + characterOffset
characterAnchor.orientation = Transform(matrix: bodyAnchor.transform).rotation
if let character = character, character.parent == nil {
characterAnchor.addChild(character)
}
}
}
}
}
ContentView.swift (User is expected to touch slider and offsetValue would be changed. SlideView has been already implemented)
import SwiftUI
import RealityKit
import ARKit
import Combine
struct ContentView : View {
#State var offsetValue:Float = 0.0
#ObservedObject var offsetInstance = Offset()
var body: some View {
VStack{
Button(action:{self.offsetInstance.setOffset(offset: 1.0)},
label:{Text("check")})
ZStack(alignment: .bottom) {
ARViewContainer(offsetValue: $offsetValue)
SlideView(offSetValue: $offsetValue)
}
}
}
}
Thank you very much for your help!