I have a human-like rigged 3D model in a DAE file. I want to programmatically build a scene with several instances of this model in different poses. I can extract the SCNSkinner and skeleton chain from the DAE file without problem. I have discovered that to have different poses, I need to clone the skeleton chain, and clone the SCNSkinner as well, then modify the skeletons position. Works fine. This is done this way: // Read the skinner from the DAE file let skinnerNode = daeScene.rootNode.childNode(withName: "toto-base", recursively: true)! // skinner let skeletonNode1 = skinnerNode.skinner!.skeleton! // Adding the skinner node as a child of the skeleton node makes it easier to // 1) clone the whole thing // 2) add the whole thing to a scene skeletonNode1.addChildNode(skinnerNode) // Clone first instance to have a second instance var skeletonNode2 = skeletonNode1.clone() // Position and move the first instance skeletonNode1.position.x = -3 let skeletonNode1_rightLeg = skeletonNode1.childNode(withName: "RightLeg", recursively: true)! skeletonNode1_rightLeg.eulerAngles.x = 0.6 scene.rootNode.addChildNode(skeletonNode1) // Position and move the second instance skeletonNode2.position.x = 3 let skeletonNode2_leftLeg = skeletonNode2.childNode(withName: "LeftLeg", recursively: true)! skeletonNode2_leftLeg.eulerAngles.z = 1.3 scene.rootNode.addChildNode(skeletonNode2) It seems the boneWeights and boneIndices sources are duplicated for each skinner, so if I have let's say 100 instances, I eat a huge amount of memory, for something that is constant. Is there any way to avoid the duplication of the boneWeights and boneIndices ?

Hi, My app has a volumetric window displaying some 3D content for the user. I would like the user to be able to control the color of the material using a color picker displayed below the model in the same window, but unfortunately neither ColorPicker nor Picker are functional in volumetric scenes. Attempting to use them causes the app to crash with NSInternalInconsistencyException: Presentations are not permitted within volumetric window scenes. This seems rather limiting. Is there a way either of these components can be utilized? I could build a different "control panel" window but it would not be attached to the model window and it would get confusing if user has multiple 3d windows open. Thank you

Hi, I'm an experienced developer on Apple platforms (having worked on iOS/tvOS projects for more than 10 years now). However, I've only worked on applications, or simple games which didn't require more than using UIKit or SwiftUI. Now, I'd like to start a new project, recreating an old game on tvOS with 3D graphics. This is not a project I plan to release, only a simple personal challenge. I'm torn with starting this project with either SceneKit, or Unity. On one hand, I love Apple frameworks and tools, so I guess I could easily progress with SceneKit. Also, I don't know Unity very well, but even if it's a simple project, I've seen that there are several restrictions for free plans (no custom splash screen, etc). On the other hand, I've read several threads (i.e. this one) making it look like that SceneKit isn't going anywhere, and clearly recommending Unity due to the fact that its documentation is way better, and the game more easily portable to other platforms. Also, if I'm going to learn something new, maybe I could learn more with Unity (using a completely different platform, software and language) than I would with SceneKit and Swift stuff. What's your opinion about this? Thanks!

I'm working on a project in Xcode where I need to use a 3D model with multiple morph targets (shape keys in Blender) for animations. The model, specifically the Wolf3D_Head node, contains dozens of morph targets which are crucial for my project. Here's what I've done so far: I verified the morph targets in Blender (I can see all the morph targets correctly when opening both the original .glb file and the converted .dae file in Blender). Given that Xcode does not support .glb file format directly, I converted the model to .dae format, aiming to use it in my Xcode project. After importing the .dae file into Xcode, I noticed that Xcode does not show any morph targets for the Wolf3D_Head node or any other node in the model. I've already attempted using tools like ColladaMorphAdjuster and another version by JakeHoldom to adjust the .dae file, hoping Xcode would recognize the morph targets, but it didn't resolve the issue. My question is: How can I make Xcode recognize and display the morph targets present in the .dae file exported from Blender? Is there a specific process or tool that I need to use to ensure Xcode properly imports all the morph target information from a .dae file? Tools tried: https://github.com/JonAllee/ColladaMorphAdjuster, https://github.com/JakeHoldom/ColladaMorphAdjuster Thanks in advance!

Hello, I am currently working on a project where I am creating a bookstore visualization with racks and shelves(Full immersive view). I have an array of names, each representing a USDZ object that is present in my working directory. Here’s the enum I am trying to iterate over: enum AssetName: String, Codable, Hashable, CaseIterable { case book1 = "B1" case book2 = "B2" case book3 = "B3" case book4 = "B4" } and the code for adding objects I wrote: import SwiftUI import RealityKit struct LocalAssetRealityView: View { let assetName: AssetName var body: some View { RealityView { content in if let asset = try? await ModelEntity(named: assetName.rawValue) { content.add(asset) } } } } Now I get the error, when I try to add multiple objects on Button click: Unable to present another Immersive Space when one is already requested or connected please suggest any solutions. Also suggest if anything can be done to add positions for the objects as well programatically.

Hello! I need to display a .scnz 3D model in an iOS app. I tried converting the file to a .scn file so I could use it with SCNScene but the file became corrupted. I also tried to instantiate a SCNScene with the .scnz file but that didn't work either (crash when instantiating it). After all this, what would be the best way to use this file knowing that converting it or exporting it to a .scn file with scntool hasn't worked? Thank you!

Dear all, I have several scenes, each with it’s own camera at different positions. The scenes will be loaded with transitions. If I set the pointOfView in every Scene to the scene-camera, the transitions don’t work properly. The active scene View switches to the position of the camera of the scene, which is fading in. If I comment the pointOfView out, the transitions works fine, but the following error message appears: Error: camera node already has an authoring node - skip Has someone an idea to fix this? Many Thanks, Ray

We have requirement adding usdz file to UIView and showing the it’s content and archive the data and save to file. When user open the file, we need to unarchive that usdz content and binding with UIView and showing it to user. Initially, we created SCNScene object passing usdz file url like below. do { usdzScene = try SCNScene(url: usdzUrl) } catch let error as NSError { print(error) } Since SCNScene support to NSSecureCoding protocol , we directly archive that object and save it file and load back it from file and created SCNScene object using NSKeyedUnarchiver process. But for some files, we realised high memory consumption while archiving the SCNScene object using below line. func encode(with coder: NSCoder) { coder.encode(self.scnScene, forKey: "scnScene") } File referene link : toy_drummer_idle.usdz When we analyse apple documentation (check discussion section) , it said, scn file extension is the fastest format for processing than the usdz. So we used SCNSecne write to feature for creating scn file from given usdz file. After that, When we do the archive SCNScene object that was created by sun file url, the archive process is more faster and it will not take high memory as well. It is really faster previous case now. But unfortunately, SCNScene write method will take lot of time for this conversion and memory meter is also going high and it will be caused to app crash as well. I check the output file size as well. The given usdz file size is 18MB and generated scn file size is 483 MB. But SCNScene archive process is so fast. Please, analyse this case and please, provide some guideline how we can optimise this behaviour. I really appreciate your feedback. Full Code: import UIKit import SceneKit class ViewController: UIViewController { var scnView: SCNView? var usdzScene: SCNScene? var scnScene: SCNScene? lazy var exportButton: UIButton = { let btn = UIButton(type: UIButton.ButtonType.system) btn.tag = 1 btn.backgroundColor = UIColor.blue btn.addTarget(self, action: #selector(buttonPressed(_:)), for: .touchUpInside) btn.setTitle("USDZ to SCN", for: .normal) btn.setTitleColor(.white, for: .normal) btn.layer.borderColor = UIColor.gray.cgColor btn.titleLabel?.font = .systemFont(ofSize: 20) btn.translatesAutoresizingMaskIntoConstraints = false return btn }() func deleteTempDirectory(directoryName: String) { let tempDirectoryUrl = URL(fileURLWithPath: NSTemporaryDirectory()) let tempDirectory = tempDirectoryUrl.appendingPathComponent(directoryName, isDirectory: true) if FileManager.default.fileExists(atPath: URL(string: tempDirectory.absoluteString)!.path) { do{ try FileManager.default.removeItem(at: tempDirectory) } catch let error as NSError { print(error) } } } func createTempDirectory(directoryName: String) -> URL? { let tempDirectoryUrl = URL(fileURLWithPath: NSTemporaryDirectory()) let toBeCreatedDirectoryUrl = tempDirectoryUrl.appendingPathComponent(directoryName, isDirectory: true) if !FileManager.default.fileExists(atPath: URL(string: toBeCreatedDirectoryUrl.absoluteString)!.path) { do{ try FileManager.default.createDirectory(at: toBeCreatedDirectoryUrl, withIntermediateDirectories: true, attributes: nil) } catch let error as NSError { print(error) return nil } } return toBeCreatedDirectoryUrl } @IBAction func buttonPressed(_ sender: UIButton){ let scnFolderName = "SCN" let scnFileName = "3D" deleteTempDirectory(directoryName: scnFolderName) guard let scnDirectoryUrl = createTempDirectory(directoryName: scnFolderName) else {return} let scnFileUrl = scnDirectoryUrl.appendingPathComponent(scnFileName).appendingPathExtension("scn") guard let usdzScene else {return} let result = usdzScene.write(to: scnFileUrl, options: nil, delegate: nil, progressHandler: nil) if (result) { print("exporting process is success.") } else { print("exporting process is failed.") } } override func viewDidLoad() { super.viewDidLoad() let usdzUrl: URL? = Bundle.main.url(forResource: "toy_drummer_idle", withExtension: "usdz") guard let usdzUrl else {return} do { usdzScene = try SCNScene(url: usdzUrl) } catch let error as NSError { print(error) } guard let usdzScene else {return} scnView = SCNView(frame: .zero) guard let scnView else {return} scnView.translatesAutoresizingMaskIntoConstraints = false self.view.addSubview(scnView) self.view.addSubview(exportButton) NSLayoutConstraint.activate([ scnView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor), scnView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor), scnView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor), scnView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor, constant: -30), exportButton.widthAnchor.constraint(equalToConstant: 200), exportButton.heightAnchor.constraint(equalToConstant: 40), exportButton.centerXAnchor.constraint(equalTo: view.safeAreaLayoutGuide.centerXAnchor), exportButton.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor), ]) DispatchQueue.main.asyncAfter(deadline: .now() + 0.01) {[weak self] in guard let self else {return} loadModel(scene: usdzScene) } } func loadModel(scene: SCNScene){ guard let scnView else {return} scnView.autoenablesDefaultLighting = true scnView.scene = scene scnView.allowsCameraControl = true } } ![]("https://developer.apple.com/forums/content/attachment/5ff0197b-7e0b-4efe-b295-cc205c73dc02" "title=Screenshot 2024-06-20 at 12.23.40.png;width=1712;height=1013")