Discuss Spatial Computing on Apple Platforms.

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VisionOS: Detect plane to place objects issue for animated objects
Hi, I have used the template code for Plane Detection and placing models on them from here https://developer.apple.com/documentation/visionos/placing-content-on-detected-planes This source code did not copy the animations in the preview model to the PlacedModel and hence I modified it to do a manual copy of animations and textures. There is a function called materialize() that does this and I was able to modify it to get it working where the placed models are now animating. The issue is when I apply gestures on them like drag or rotate. For those models that go through this logic I'm unable to add gestures even though I'm making sure that Collision and Input Target is set on the Placed Models. Has anyone been able to get this working or is it even a possibility? My materialize function func materialize() -> PlacedObject { let shapes = previewEntity.components[CollisionComponent.self]!.shapes // Clone render content first as we need its materials let clonedRenderContent = renderContent.clone(recursive: true) print("To be finding main model: \(descriptor.displayName)") // Find the main model in preview hierarchy func findMainModel(_ entity: Entity) -> Entity? { if entity.name == descriptor.displayName.replacingOccurrences(of: " ", with: "_") { print("Found main model: \(entity.name)") return entity } for child in entity.children { if child.name == descriptor.displayName.replacingOccurrences(of: " ", with: "_") { print("Found main model in children: \(child.name)") return child } } return nil } // Clone hierarchy preserving structure, names, and materials func cloneHierarchy(_ entity: Entity) -> Entity { print("Cloning: \(entity.name)") let cloned: Entity if let model = entity as? ModelEntity { // Clone with recursive false to handle children manually cloned = model.clone(recursive: false) if let clonedModel = cloned as? ModelEntity, let originalMaterials = model.model?.materials { // Preserve the original model's materials clonedModel.model?.materials = originalMaterials } } else { cloned = Entity() } // Preserve name and transform cloned.name = entity.name cloned.transform = entity.transform // Clone children for child in entity.children { let clonedChild = cloneHierarchy(child) cloned.addChild(clonedChild) } return cloned } print("=== Cloning Preview Structure ===") // Clone the preview hierarchy with proper structure let clonedStructure = cloneHierarchy(previewEntity) // Find and use the main model if let mainModel = findMainModel(clonedStructure) { print("Using main model for PlacedObject") let modelEntity: ModelEntity if let asModel = mainModel as? ModelEntity { print("Using asModel ") modelEntity = asModel } else { modelEntity = ModelEntity() modelEntity.name = mainModel.name // Copy children and transforms for child in mainModel.children { modelEntity.addChild(child) } modelEntity.transform = mainModel.transform } // Add collision component here let collisionComponent = CollisionComponent(shapes: shapes, isStatic: false, filter: CollisionFilter(group: PlacedObject.collisionGroup, mask: .all)) modelEntity.components.set(collisionComponent) // Create the placed object let placedObject = PlacedObject(descriptor: descriptor, renderContentToClone: modelEntity, shapes: shapes) // Set input target on the placed object itself placedObject.components.set(InputTargetComponent(allowedInputTypes: [.direct, .indirect])) return placedObject } else { print("Fallback to original render content") let placedObject = PlacedObject(descriptor: descriptor, renderContentToClone: clonedRenderContent, shapes: shapes) placedObject.components.set(InputTargetComponent(allowedInputTypes: [.direct, .indirect])) return placedObject } } My PlacedObject class where the init has the recursive cloning removed because it is handled in materialize class PlacedObject: Entity { let fileName: String // The 3D model displayed for this object. private let renderContent: ModelEntity static let collisionGroup = CollisionGroup(rawValue: 1 << 29) // The origin of the UI attached to this object. // The UI is gravity aligned and oriented towards the user. let uiOrigin = Entity() var affectedByPhysics = false { didSet { guard affectedByPhysics != oldValue else { return } if affectedByPhysics { components[PhysicsBodyComponent.self]!.mode = .static } else { components[PhysicsBodyComponent.self]!.mode = .static } } } var isBeingDragged = false { didSet { affectedByPhysics = !isBeingDragged } } var positionAtLastReanchoringCheck: SIMD3<Float>? var atRest = false init(descriptor: ModelDescriptor, renderContentToClone: ModelEntity, shapes: [ShapeResource]) { fileName = descriptor.fileName // renderContent = renderContentToClone.clone(recursive: true) renderContent = renderContentToClone super.init() name = renderContent.name // Apply the rendered content’s scale to this parent entity to ensure // that the scale of the collision shape and physics body are correct. scale = renderContent.scale renderContent.scale = .one // Make the object respond to gravity. let physicsMaterial = PhysicsMaterialResource.generate(restitution: 0.0) let physicsBodyComponent = PhysicsBodyComponent(shapes: shapes, mass: 1.0, material: physicsMaterial, mode: .static) components.set(physicsBodyComponent) components.set(CollisionComponent(shapes: shapes, isStatic: false, filter: CollisionFilter(group: PlacedObject.collisionGroup, mask: .all))) addChild(renderContent) addChild(uiOrigin) uiOrigin.position.y = extents.y / 2 // Position the UI origin in the object’s center. // Allow direct and indirect manipulation of placed objects. components.set(InputTargetComponent(allowedInputTypes: [.direct, .indirect])) // Add a grounding shadow to placed objects. renderContent.components.set(GroundingShadowComponent(castsShadow: true)) } required init() { fatalError("`init` is unimplemented.") } } Thanks
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445
Feb ’25
USDZ with Blend Shapes Workflow Recommendations
Hi, since RealityKit 4 now supports Blend Shapes I was wondering if there are any workflow or tooling recommendations to bake/export them into a USDZ. Are Blender or Cinema4D capable to do that out of the box? Should we look into NVIDIA omniverse (https://docs.omniverse.nvidia.com/connect/latest/blender/manual.htm) So far this topic seems very sparsely documented and I would appreciate any hints. Thank you!
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1.4k
Jan ’25
Cannot extract imagePair from generated Spatial Photos
Hi I am trying to implement something simple as people can share their Spatial Photos with others (just like this post). I encountered the same issue with him, but his answer doesn't help me out here. Briefly speaking, I am using CGImgaeSoruce to extract paired leftImage and rightImage from one fetched spatial photo let photos = PHAsset.fetchAssets(with: .image, options: nil) // enumerating photos .... if asset.mediaSubtypes.contains(PHAssetMediaSubtype.spatialMedia) { spatialAsset = asset } // other code show below I can fetch left and right images from native Spatial Photo (taken by Apple Vision Pro or iPhone 15+), but it didn't work on generated spatial photo (2D -> 3D feat in Photos). // imageCount is 1 when it comes to generated spatial photo let imageCount = CGImageSourceGetCount(source) I searched over the net and someone says the generated version is having a depth image instead of left/right pair. But still I cannot extract any depth image from imageSource. The full code below, the imagePair extraction will stop at "no groups found": func extractPairedImage(phAsset: PHAsset, completion: @escaping (StereoImagePair?) -> Void) { let options = PHImageRequestOptions() options.isNetworkAccessAllowed = true options.deliveryMode = .highQualityFormat options.resizeMode = .none options.version = .original return PHImageManager.default().requestImageDataAndOrientation(for: phAsset, options: options) { imageData, _, _, _ in guard let imageData, let imageSource = CGImageSourceCreateWithData(imageData as CFData, nil) else { completion(nil) return } let stereoImagePair = stereoImagePair(from: imageSource) completion(stereoImagePair) } } } func stereoImagePair(from source: CGImageSource) -> StereoImagePair? { guard let properties = CGImageSourceCopyProperties(source, nil) as? [CFString: Any] else { return nil } let imageCount = CGImageSourceGetCount(source) print(String(format: "%d images found", imageCount)) guard let groups = properties[kCGImagePropertyGroups] as? [[CFString: Any]] else { /// function returns here print("no groups found") return nil } guard let stereoGroup = groups.first(where: { let groupType = $0[kCGImagePropertyGroupType] as! CFString return groupType == kCGImagePropertyGroupTypeStereoPair }) else { return nil } guard let leftIndex = stereoGroup[kCGImagePropertyGroupImageIndexLeft] as? Int, let rightIndex = stereoGroup[kCGImagePropertyGroupImageIndexRight] as? Int, let leftImage = CGImageSourceCreateImageAtIndex(source, leftIndex, nil), let rightImage = CGImageSourceCreateImageAtIndex(source, rightIndex, nil), let leftProperties = CGImageSourceCopyPropertiesAtIndex(source, leftIndex, nil), let rightProperties = CGImageSourceCopyPropertiesAtIndex(source, rightIndex, nil) else { return nil } return (leftImage, rightImage, self.identifier) } Any suggestion? Thanks visionOS 2.4
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144
Jun ’25
Setting clip shape of a RealityView
I am following this example to create a stereoscopic image: https://developer.apple.com/documentation/visionos/creating-stereoscopic-image-in-visionos I would also like to add corner radius to the stereoscopic RealityView. With ordinary SwiftUI views, we typically just use .clipShape(RoundedRectangle(cornerRadius: 32)): struct StereoImage: View { var body: some View { let spacing: CGFloat = 10.0 let padding: CGFloat = 40.0 VStack(spacing: spacing) { Text("Stereoscopic Image Example") .font(.largeTitle) RealityView { content in let creator = StereoImageCreator() guard let entity = await creator.createImageEntity() else { print("Failed to create the stereoscopic image entity.") return } content.add(entity) } .frame(depth: .zero) } .padding(padding) .clipShape(RoundedRectangle(cornerRadius: 32)) // <= HERE! } } This doesn't seem to actually clip the RealityView shown in the sample above. I am guessing this is due to the fact that the box in the RealityView has a non-zero z scale, which means it isn't on the same "layer" as its SwiftUI containers, and thus isn't clipped by the modifiers apply to the containers. How can I properly apply a clipshape to RealityViews like this? Thanks!
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472
Feb ’25
WorldTrackingProvider stops working on device
After re-launching the immersive space in my app 5-10 times, the WorldTrackingProvider stops working. Only restarting the app will allow it to start working again. Only on device, not the simulator. I get these errors when it happens: The device_anchor can only be queried when the world tracking provider is running. ARPredictorRemoteService <0x107cbb5e0>: Service configured with error: Error Domain=com.apple.arkit.error Code=501 "(null)" Remote Service was invalidated: <ARPredictorRemoteService: 0x107cbb5e0>, will stop all data_providers. ARRemoteService: remote object proxy failed with error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service with pid 81 named com.apple.arkit.service.session was invalidated from this process." UserInfo={NSDebugDescription=The connection to service with pid 81 named com.apple.arkit.service.session was invalidated from this process.} ARRemoteService: weak self released before invalidation @Observable class VisionPro { let session = ARKitSession() let worldTracking = WorldTrackingProvider() func transformMatrix() async -> simd_float4x4 { guard let deviceAnchor = worldTracking.queryDeviceAnchor(atTimestamp: CACurrentMediaTime()) else { return .init() } return deviceAnchor.originFromAnchorTransform } func runArkitSession() async { Task { try? await session.run([worldTracking]) } } } which I call from my RealityView: .task { await visionPro.runArkitSession() }
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435
Feb ’25
Looking for a way to implement the video display effect in Apple's 'Spatial Gallery'
Hi guys, I noticed that Apple created a really engaging visual effect for browsing spatial videos in the app. The video appears embedded in glass panel with glowing edges and even shows a parallax effect as you move around. When I tried to display the stereo video using RealityView, however, the video entity always floats above the panel. May I ask how does VisionOS implement this effect? Is there any approach to achieve this effect or example code I can use in my own code. Thanks!
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209
Jun ’25
Creating a voxel mesh and render it using metal within a RealityKit ImmersiveView
Hi everyone, I'm creating an educational App that allows doing computational design in an immersive environment with the Vision Pro. The App is free and can be found here: https://apps.apple.com/us/app/arcade-topology/id6742103633 The problem I have is that the mesh of voxels I currently create use ModelEntity and I recently read that this is horrible for scalability. I already start to see issues when I try to use thousands of voxels. I also read somewhere that I should then take advantage of GPUs and use metal to that end. I was wondering if someone could point me to a tutorial or article that discusses this. In essence, I need to create a 3D voxel mesh, and those voxels have to update their opacity within an iterative loop. Thanks! —Alejandro
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129
Jun ’25
Reading scenePhase from custom Scene
Hi, I've encountered a thread where an Apple engineer points out that there are 2 possible ways to anchor scenePhase, either App or View implementation: https://developer.apple.com/forums/thread/757429 This thread also links to documentation which states If you read the phase from within a custom Scene instance, the value similarly reflects an aggregation of all the scenes that make up the custom scene: This doesn't seem to be the case on visionOS 2, I tried the following code starting from an empty app template: import SwiftUI @main struct SceneTestApp: App { var body: some Scene { MyScene() WindowGroup(id: "extra") { Text("Extra window") } } } struct MyScene: Scene { @Environment(\.scenePhase) private var scenePhase @Environment(\.openWindow) private var openWindow var body: some Scene { WindowGroup { ContentView() .onAppear { openWindow(id: "extra") } } .onChange(of: scenePhase) { oldValue, newValue in print("scenePhase changed") } } } The result was that I didn't get onChange callback if I only closed the extra window, the callback only came after I closed both windows and the whole app was suspended. Is this expected behavior?
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373
Feb ’25
For a third year, no screenshot capability for immersive visionOS apps... here's a workaround?
Since only the user can take a screenshot using the Apple Vision Pro's top buttons, the only workaround available to an immersive app that needs a screenshot to document the user's creative interior design choices is ask the user to take a screenshot wait until the user taps a button indicating the screenshot has been taken then the app asks the user to select the screenshot when the app opens the PhotoPicker when the user presses Done, the screenshot is handed off to the app. One wonders why there is no Apple Api for doing this in a simple privacy protective way such as: When called, the Apple api captures the screenshot in Apple secured memory The api displays the screenshot to the user with appropriate privacy warnings and asks if the user wants to a. share this screenshot with the app, or b. cancel, c. retake the screenshot If the user approves, the app receives the screenshot
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83
Jun ’25
Vision OS: HUD mode windows
If I correctly understand, a new Enterprise API has been introduced In visionOS 26 allowing to fix windows to the user frame of reference, implementing a something like an "head up display", with the window tracking the user movements. Is this API only available to enterprise applications, and if so is there a plan to make it available for every kind of app?
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107
Jun ’25
RealityView Not Refreshing With SwiftData
Hi, I am trying to update what entities are visible in my RealityView. After the SwiftData set is updated, I have to restart the app for it to appear in the RealityView. Also, the RealityView does not close when I move to a different tab. It keeps everything on and tracking, leaving the model in the same location I left it. import SwiftUI import RealityKit import MountainLake import SwiftData struct RealityLakeView: View { @Environment(\.modelContext) private var context @Query private var items: [Item] var body: some View { RealityView { content in print("View Loaded") let lakeScene = try? await Entity(named: "Lake", in: mountainLakeBundle) let anchor = AnchorEntity(.plane(.horizontal, classification: .any, minimumBounds: SIMD2<Float>(0.2, 0.2))) @MainActor func addEntity(name: String) { if let lakeEntity = lakeScene?.findEntity(named: name) { // Add the Cube_1 entity to the RealityView anchor.addChild(lakeEntity) } else { print(name + "entity not found in the Lake scene.") } } addEntity(name: "Island") for item in items { if(item.enabled) { addEntity(name: item.value) } } // Add the horizontal plane anchor to the scene content.add(anchor) content.camera = .spatialTracking } placeholder: { ProgressView() } .edgesIgnoringSafeArea(.all) } } #Preview { RealityLakeView() }
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515
Jan ’25
RealityKit Trace Metric Max/Range for VisionOS app
Hi Nathaniel, I spoke with you yesterday in the WWDC lab. Thanks for chatting with me! Is it possible to get a link to a doc that has some key metrics I'd find in a RealityKit trace so I know if that metric is exceeding limits and probably causing a problem? Right now, I just see numbers and have no idea if a metric is high or low :). This is specifically for a VisionOS app. Thanks, Bob
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132
Jun ’25
[WWDC25] For GuessTogether, can you initiate a FaceTime call via the custom SharePlay button?
Hello, For GuessTogether source code, it seems like the code assumes that you're already in a FaceTime call before pressing the custom SharePlay button (labeled "Play Guess Together"). If not already on a FaceTime call, my Apple Vision Pro and the visionOS simulator both do nothing after throwing warnings. Is this intended behavior? If so, how do I make it so that pressing the button can also initiate FaceTime calls? Is this allowed? Thank you!
3
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114
Sep ’25
RotateGesture3D auto constrained to axis
Hi, On visionOS to manage entity rotation we can rely on RotateGesture3D. We can even with the constrainedToAxis parameter authorize only rotation on an x, y or z axis or even make combinations. What I want to know is if it is possible to constrain the rotation on axis automatically. Let me explain, the functionality that I would like to implement is to constrain the rotation on an axis only once the user has started his gesture. The initial gesture the user makes should let us know which axis they want to rotate on. This would be equivalent to activating a constraint automatically on one of the axes, as if we were defining the gesture on one of the axes. RotateGesture3D(constrainedToAxis: .x) RotateGesture3D(constrainedToAxis: .y) RotateGesture3D(constrainedToAxis: .z) Is it possible to do this? If so, what would be the best way to do it? A code example would be greatly appreciated. Regards Tof
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422
Feb ’25
Loading USDZ asset into Model3D causes visionOS 2.0 beta 5 to crash
We've recently discovered that our app crashes on startup on the latest visionOS 2.0 beta 5 (22N5297g) build. In fact, the entire field of view would dim down and visionOS would then restart, showing the Apple logo. Interestingly, no app crash is reported by Xcode during debug. After investigation, we have isolated the issue to a specific USDZ asset in our app. Loading it in a sample, blank project also causes visionOS to reliably crash, or become extremely unresponsive with rendering artifacts everywhere. This looks like a potentially serious issue. Even if the asset is problematic, loading it should not crash the entire OS. We have filed feedback FB14756285, along with a demo project. Hopefully someone can take a look. Thanks!
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564
Jul ’25
RealityKit Entity ComponentSet does not conform to Sequence?
Hello, I'm trying to view the components of an Entity I'm creating in RealityKit by reading from a USDZ file. I have the following code snippet in my app. if let appleEntity = try? Entity.loadModel(named: "apple_tile") { let c = appleEntity.components for comp in c { // <- compiler error here print(comp) } } The compiler error I'm receiving says "For-in loop requires 'Entity.ComponentSet' to conform to 'Sequence'". However, I thought this was the case, according to the documentation for Entity.ComponentSet? Curious if anyone else has had this problem. Running XCode 15.4, and my Swift version is xcrun swift -version swift-driver version: 1.90.11.1 Apple Swift version 5.10 (swiftlang-5.10.0.13 clang-1500.3.9.4) Target: x86_64-apple-macosx14.0
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411
Mar ’25
ManipulationComponent create parent/child crash
Hello, If you add a ManipulationComponent to a RealityKit entity and then continue to add instructions, sooner or later you will encounter a crash with the following error message: Attempting to move entity “%s” (%p) under “%s” (%p), but the new parent entity is currently being removed. Changing the parent/child entities of an entity in an event handler while that entity is already being reassigned is not supported. CoreSimulator 1048 – Device: Apple Vision Pro 4K (B87DD32A-E862-4791-8B71-92E50CE6EC06) – Runtime: visionOS 26.0 (23M336) – Device Type: Apple Vision Pro The problem occurs precisely with this code: ManipulationComponent.configureEntity(object) I adapted Apple's ObjectPlacementExample and made the changes available via GitHub. The desired behavior is that I add entities to ManipulationComponent and then Realitiykit runs stably and does not crash randomly. GitHub Repo Thanks Andre
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460
Oct ’25
MainActor attribute on RealityKit APIs is causing problems
Hello, A lot of the RealityKit APIs (Ex. LowLevelMesh, LowLevelTexture, etc.) are marked with MainActor so they needed to be accessed on the main thread. This creates issues when we need to perform expensive GPU related operations since now we need to perform those on the main thread. This results in bottlenecks and hangs in our application. We would like to use a multi-threaded approach to solve these problems which is difficult to do here. We are constantly streaming data whether the app is just appearing or the user is interacting with our application so we need to be able to perform these operations on a separate thread. Any advice on how to achieve this using RealityKit? Thank you.
3
8
204
Mar ’25