RealityKit for VR

Question

Trying to use my RealityKit project as the foundation for an on screen app (VR) instead of projecting onto the real-world (AR) out the back camera.

Anyone know how to load a RealityKit project asynchronously with the .nonAR camera option, so it project in an app instead of leveraging the rear facing camera?

Do I create position information in the Swift code or the Reality Composer project?

Answer 1

Here's how you can asynchronously load .usdz VR-model with a help of RealityKit's .loadModelAsync() instance method and Combine's AnyCancellable type.

import UIKit
import RealityKit
import Combine

class VRViewController: UIViewController {
    
    @IBOutlet var arView: ARView!
    var anyCancellable: AnyCancellable? = nil
    let anchorEntity = AnchorEntity(world: [0, 0,-2])
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        arView.backgroundColor = .black
        arView.cameraMode = .nonAR

        anyCancellable = ModelEntity.loadModelAsync(named: "horse").sink(
                        
            receiveCompletion: { _ in
                self.anyCancellable?.cancel()
            },
            
            receiveValue: { [self] (object: Entity) in
                if let model = object as? ModelEntity {
                    self.anchorEntity.addChild(model)
                    self.arView.scene.anchors.append(self.anchorEntity)
                } else {
                    print("Can't load a model due to some issues")
                }
            }
        )
    }
}

However, if you wanna move inside 3D environment, instead of using .nonAR camera mode use:

arView.environment.background = .color(.black)