How to project shadows on meshed environment in RealityKit? - augmented-reality

Question

I'm using RealityKit in combination with a USDZ model and scene understanding (LiDAR iPhone), and simply want my model to project some nice shadows on the real-world environment. I can easily get a custom spotlight on my model, but fail to project any shadows from my it.
I'm stuck with what appears to be the default top-down lighting.
What am I doing wrong?
My code:
override func viewDidLoad() {
super.viewDidLoad()
arView.session.delegate = self
arView.environment.sceneUnderstanding.options = []
arView.environment.sceneUnderstanding.options.insert(.receivesLighting)
arView.automaticallyConfigureSession = false
let configuration = ARWorldTrackingConfiguration()
configuration.planeDetection = [.horizontal, .vertical]
configuration.sceneReconstruction = .mesh
configuration.environmentTexturing = .automatic
arView.session.run(configuration) }
Here's the function I call when adding a model
#IBAction func addMyModel(_ sender: Any) {
do {
let mymodel = try ModelEntity.load(named: "mymodel")
// Lights
let spotLight = CustomSpotLight()
let anchor = AnchorEntity(plane: .horizontal, minimumBounds: [0.30, 1.00])
anchor.children.append(mymodel)
anchor.addChild(spotLight)
self.arView.scene.anchors.append(anchor)
} catch {
fatalError("Failed to load asset.")
}
}
and finally here's my custom spotlight code:
import ARKit
import RealityKit
class CustomSpotLight: Entity, HasSpotLight {
required init() {
super.init()
self.light = SpotLightComponent(color: .blue,
intensity: 500000,
innerAngleInDegrees: 45,
outerAngleInDegrees: 169,
attenuationRadius: 9.0)
self.shadow = SpotLightComponent.Shadow()
self.position.y = 5.0
self.orientation = simd_quatf(angle: -.pi/1.5,
axis: [1,0,0])
}
}