swift - 显示来自网络的现实文件时出错

Question

我正在尝试显示 reality使用 Reality Composer 创建的文件.以下代码适用于 usdz但不适用于 reality .这是我的代码

struct ARViewContainer: UIViewRepresentable {
    
    var modelConfirmedForPlacement: AnchorEntity?
    
    func makeUIView(context: Context) -> ARView {
        
        let arView = ARView(frame: .zero,
                            cameraMode: .ar,automaticallyConfigureSession: true)
        
        let config = ARFaceTrackingConfiguration()
            
        arView.session.run(config)
        return arView            
    }
    
    func updateUIView(_ uiView: ARView, context: Context) {
        if let modelEntity = modelConfirmedForPlacement {
                      
           // Add the box anchor to the scene
            uiView.scene.anchors.append(modelEntity)   
        }
    }
}

// View 模型

final class ContentViewModel: ObservableObject {
    
    @Published var modelConfirmedForPlacement: AnchorEntity?
    
    private var cancellable: AnyCancellable? = nil
    
    func updateModelEntity(path: String){
        let url = URL(fileURLWithPath: path)
        self.cancellable = AnchorEntity.loadAnchorAsync(contentsOf: url)
            .sink(receiveCompletion: { loadCompletion in
                if case let .failure(error) = loadCompletion {
                    print("Unable to load a model due to error \(error)")
                }
                self.cancellable?.cancel()
            }, receiveValue: { modelEntity in
                debugPrint("hereeeeeeeee")
                self.modelConfirmedForPlacement = modelEntity
            })
    }

func loadFileSync(url: URL, completion: @escaping (String?, Error?) -> Void)
    { 
//load from network and save locally }

该文件确实在本地正确保存，但对于现实文件，它没有显示
这是 Xcode 日志

File already exists [/var/mobile/Containers/Data/Application/880ED2EE-CCE7-4EE5-B854-0D1398650705/Documents/Experience.reality]
2021-07-25 16:29:09.060267+0530 RealityKitLoadModelFromNetwork[1352:474463] Metal GPU Frame Capture Enabled
2021-07-25 16:29:09.060478+0530 RealityKitLoadModelFromNetwork[1352:474463] Metal API Validation Enabled

Answer 1

上传 .reality来自网络的模型工作正常。您可以在 Xcode Simulator 中轻松检查:

import UIKit
import RealityKit

class ViewController: UIViewController {
    
    @IBOutlet var arView: ARView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let url = URL(string: "https://developer.apple.com/augmented-reality/quick-look/models/cosmonaut/CosmonautSuit_en.reality")
        let documents = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
        let destination = documents.appendingPathComponent(url!.lastPathComponent)
        let session = URLSession(configuration: .default,
                                      delegate: nil,
                                 delegateQueue: nil)
        
        var request = URLRequest(url: url!)
        request.httpMethod = "GET"
        
        let downloadTask = session.downloadTask(with: request, completionHandler: { (location: URL?,
                                  response: URLResponse?,
                                     error: Error?) -> Void in
            
            let fileManager = FileManager.default
                
            if fileManager.fileExists(atPath: destination.path) {
                try! fileManager.removeItem(atPath: destination.path)
            }
            try! fileManager.moveItem(atPath: location!.path,
                                      toPath: destination.path)
                
            DispatchQueue.main.async {
                do {
                    let model = try Entity.loadAnchor(contentsOf: destination)
                    self.arView.scene.addAnchor(model)
                } catch {
                    print("Fail loading entity.")
                }
            }
        })
        downloadTask.resume()
    }
}