Hi, I'm playing now with hand tracking. I want to get position of hand inside a system update function. I was not sure if transform I'm getting from hand attached AnchorEntity (with trackingMode: .predicted) would give same results as handAnchors(at:) from hand tracking provider, so I started to read them both and compare. For handAnchors i tried using context.scene.timebase.sourceTimebase!.sourceClock!.time.seconds and CACurrentMediaTime() as timestamp source. They seem to use exactly same clock, so that doesn't matter, but: for some reason update handler is always called twice with same context.deltaTime, but first time the query finds 0 entities, second time it finds them all. The query is the standard EntityQuery(where: .has(MyComponent.self)) and in update (matching: Self.query, updatingSystemWhen: .rendering). Here's part of logs: System update called, entity count: 0, dt: 0.01000458374619484, absTime: 4654.222593541 System update called, entity count: 11, dt: 0.01000458374619484, absTime: 4654.22262525 System update called, entity count: 0, dt: 0.009999999776482582, absTime: 4654.249390875 System update called, entity count: 11, dt: 0.009999999776482582, absTime: 4654.249425 accounting for the double update calling I started to calculate time delta of absolute time between calls and they're most of the time much bigger, or much smaller than advertised by system's context.deltaTime, only sometimes they kind of match, for example: system: (dt: 0.01000458374619484) scene : (dt: 0.021419291667371) (absTime: 4654.222628125001) and the very next call system: (dt: 0.010009 166784584522) scene : (dt: 0.0013097083328830195) (absTime: 4654.223937833334) but sometimes system: (dt: 0.009999999776482582) scene : (dt: 0.009 112249999816413) (absTime: 4654.351299 166668) Shouldn't those be more or less equal, or am I missing something? In the end it seems that getting hand position from AnchorEntity and with handAnchors(at:) gives kind of same results, but at different time points, so I'd love to understand what's the correct way to use them and why time flows differently :). --Edit-- P.S. Had to put spaces everywhere in logs between "9" and "1", otherwise post was blocked due to "sensitive content" :D

I am trying to launch a fully immersive game from Unity on a SwiftUI view. The game is using Metal Rendering with Compositor Services. I added the unity Xcode project into the workspace, added the necessary bridge code. When I click on the button to call ufw?.showUnityWindow(), it does not start and I get the following in the console: AR session failed to start after 5 seconds. Is the app configured to use an immersive space?

In Reality Composer, it is possible to create child components and manipulate them within the hierarchy of a ModelEntity. Is there a way to create child components in other 3D modeling programs, such as Blender?

I have two cubes in my blender project. But one gets lost after importing the USDZ file which is exported from the blender project. It seems that Apple frameworks don't support non-English USDZ.

Currently I am using mixed style immersive view to place both my WindowView(plain style) and ImmersiveView content together. The issue is that the rendering depth testing may always let the virtual content block my normal WindowView. Is it possible to manually set windowedVIew always displays in the front of my virtual view in mixed style immersion? (I know modelSortGroup but it doesn't quite fits here) Or if I can dynamically change the .progressive value when the immersive space is open (set the value to zero means .mixed itself right?)

I am encountering an issue while using the multiview video demo provided at this link "https://developer.apple.com/documentation/avkit/creating-a-multiview-video-playback-experience-in-visionos/". Specifically, when running on versions of visionOS prior to 2.2, navigating back results in a blank screen. Has anyone else experienced this problem and found a solution? Any advice or workaround would be greatly appreciated.

I am trying the image tracking of ARKit on VisionPro, but there seems to be some problem when adding reference image. Here is my code: let images = ReferenceImage.loadReferenceImages(inGroupNamed: "photos") print("Images: \(images)") try await appState!.arkitSession.run([imageTracking]) It can successfully print those images, however sometimes it will print the error message like this: ARImageTrackingRemoteService: Adding reference image <ARReferenceImage: 0x3032399e0 name="chair" physicalSize=(0.070, 0.093)> failed. When this error message is printed, the corresponding image can not be tracked. I do not understand why this will happen, because sometimes the image can be successfully added, but other time not, even for the same image. It makes my app not stable. Besides, there are some other error messages, and I do not know whether it is related: ARPredictorRemoteService <0x1042154a0>: Query queue is not running. Execution of the command buffer was aborted due to an error during execution. Insufficient Permission (to submit GPU work from background) (00000006:kIOGPUCommandBufferCallbackErrorBackgroundExecutionNotPermitted)

A few users have recently reported no longer being able to capture point clouds using our app, specifically on iPhone 15 Pro devices. We recently found an in-house device that exhibits this behavior and found that the confidenceMap contains only low confidence values, regardless of the environment being captured. Our app uses a higher confidence threshold; setting the threshold to a lower value produces noisy results as expected, so that is a non-viable option. Other LiDAR based apps have been tested with this device and the results are the same. No points, or noisy point clouds in apps that allow a lower confidence threshold setting. On devices that exhibit this behavior the "Displaying a point cloud using scene depth" Apple sample app can be used to visualize the issue. First reports of this new behavior occurred as early as iOS 18.4. Looking for recommendations on which team(s) at Apple to reach out to with these findings since the behavior manifests on only a small sample of devices.

Using Unity to develop VisionOS program, pressing the right knob of VisionPro during use will exit the Unity space and destroy the model in the space. The model in the space has been disconnected from the SwiftUI interface. After clicking the right knob, return to the system main interface, and then click the right knob again to return to the inside of the program. However, Unity space cannot be restored, and calling the discisWindow method on the SwiftUI interface has no effect, so the interface cannot be destroyed. Is there any solution??

If I place the .usdz file in the project directory alongside other .swift files, ModelEntity loads it perfectly. However, if I try to load the same file from Reality Composer Pro under RealityKitContent.rkassets, I get the error: resourceNotFound("heart"). Could someone help me with this? Thank you so much Code: // // TestttttttApp.swift // Testtttttt // // Created by Zhendong Chen on 2/17/25. // import SwiftUI @main struct TestttttttApp: App { var body: some Scene { WindowGroup { ContentView() } .windowStyle(.volumetric) } } // // ContentView.swift // Testtttttt // // Created by Zhendong Chen on 2/17/25. // import SwiftUI import RealityKit import RealityKitContent struct ContentView: View { @State private var enlarge = false var body: some View { RealityView { content in do { // MARK: Work let scene = try await ModelEntity(named: "heart") content.add(scene) // MARK: Doesn't work // let scene = try await ModelEntity(named: "heart", in: realityKitContentBundle) // content.add(scene) } catch { print(error) } } } } #Preview(windowStyle: .volumetric) { ContentView() }

Can you help to write a code able to pick an element a bit far from me, then bring it near to me, flick it a bit and then send it back to its original position when I release it? Thanks a lot, Christophe

We have a project which is currently being built as a XCFramework. The framework contains a custom component to be used with entities in Reality Composer Pro. I have tried to se set the RCP Package.swift file to reference the framework package for the in the dependancies. Nothing that I do with the folder path to reference the code is working. Do I need to change the project to be using Swift source code instead of a XCFramework? The component needs to be in the framework as there is a class in the framework that works directly with the custom compoent. I am able to reference the XCFramework as a Swift Package with other projects.

Apple published a set of examples for using system gestures to interact with RealityKit entities. I've been using DragGesture a lot in my apps and noticed an issue when using it in an immersive space. When dragging an entity, if I turn my body to face another direction, the dragged entity does not stay relative to my hand. This can lead to situations where the entity is pulled very close to me, or pushed far way, or even ends up behind me. In the examples linked above, there are two versions of how they use drag. handleFixedDrag: This is similar to what I'm doing now. It uses the value from value.gestureValue.translation3D as the basis for the drag handlePivotDrag: This version aims to solve the problem I described above by using value.inputDevicePose3D as the basis of the gesture. I've tried the example from handlePivotDrag, but it has one limitation. Using this version, I can move the entity around me as if it were on the inside of an arc or sphere. However, I can no longer move the entity further or closer. It stays within a similar (though not exact) distance relative to me while I drag. Is there a way to combine these concepts? Ideally, I would like to use a gesture that behaves the same way that visionOS windows do. When we drag windows, I can move them around relative to myself, pull them closer, push them further, all while avoiding the issues described above. Example from handleFixedDrag mutating private func handleFixedDrag(value: EntityTargetValue<DragGesture.Value>) { let state = EntityGestureState.shared guard let entity = state.targetedEntity else { fatalError("Gesture contained no entity") } if !state.isDragging { state.isDragging = true state.dragStartPosition = entity.scenePosition } let translation3D = value.convert(value.gestureValue.translation3D, from: .local, to: .scene) let offset = SIMD3<Float>(x: Float(translation3D.x), y: Float(translation3D.y), z: Float(translation3D.z)) entity.scenePosition = state.dragStartPosition + offset if let initialOrientation = state.initialOrientation { state.targetedEntity?.setOrientation(initialOrientation, relativeTo: nil) } } Example from handlePivotDrag mutating private func handlePivotDrag(value: EntityTargetValue<DragGesture.Value>) { let state = EntityGestureState.shared guard let entity = state.targetedEntity else { fatalError("Gesture contained no entity") } // The transform that the pivot will be moved to. var targetPivotTransform = Transform() // Set the target pivot transform depending on the input source. if let inputDevicePose = value.inputDevicePose3D { // If there is an input device pose, use it for positioning and rotating the pivot. targetPivotTransform.scale = .one targetPivotTransform.translation = value.convert(inputDevicePose.position, from: .local, to: .scene) targetPivotTransform.rotation = value.convert(AffineTransform3D(rotation: inputDevicePose.rotation), from: .local, to: .scene).rotation } else { // If there is not an input device pose, use the location of the drag for positioning the pivot. targetPivotTransform.translation = value.convert(value.location3D, from: .local, to: .scene) } if !state.isDragging { // If this drag just started, create the pivot entity. let pivotEntity = Entity() guard let parent = entity.parent else { fatalError("Non-root entity is missing a parent.") } // Add the pivot entity into the scene. parent.addChild(pivotEntity) // Move the pivot entity to the target transform. pivotEntity.move(to: targetPivotTransform, relativeTo: nil) // Add the targeted entity as a child of the pivot without changing the targeted entity's world transform. pivotEntity.addChild(entity, preservingWorldTransform: true) // Store the pivot entity. state.pivotEntity = pivotEntity // Indicate that a drag has started. state.isDragging = true } else { // If this drag is ongoing, move the pivot entity to the target transform. // The animation duration smooths the noise in the target transform across frames. state.pivotEntity?.move(to: targetPivotTransform, relativeTo: nil, duration: 0.2) } if preserveOrientationOnPivotDrag, let initialOrientation = state.initialOrientation { state.targetedEntity?.setOrientation(initialOrientation, relativeTo: nil) } }

I’m working on a Vision Pro app using Metal and need to implement multi-pass rendering. Specifically, I want to render intermediate results to a texture, then use that texture in a second pass for post-processing before presenting the final output. What’s the best approach in visionOS? Should I use multiple render passes in a single command buffer or separate command buffers? Any insights on efficiently handling this in RealityKit or Metal? Thanks!

Hi, since iOS 18 UnlitMaterial and ShaderGraphMaterial have the option to disable tone mapping, e.g via https://developer.apple.com/documentation/realitykit/unlitmaterial/init(applypostprocesstonemap:) Is it possible to do the same for CustomMaterial? I tried initializing a CustomMaterial based on an UnlitMaterial where tone mapping is disabled, like so: let unlitMat = UnlitMaterial(applyPostProcessToneMap: false) let customMaterial = try CustomMaterial( from: unlitMat, surfaceShader: surfaceShader, geometryModifier: geometryModifier ) but that does not seem to work. The colors of my texture still look altered in comparison to a plain UnlitMaterial or a ShaderGraphMaterial where its disabled. Any hints? Thank you!

I'm working on an iOS app using ARKit and RealityKit where I scan QR codes and want to place 3D models at the exact position of the QR code in the real world. Is it possible to accurately place a 3D model at the exact position of a QR code in AR using ARKit and RealityKit? Specifically, I want the model to appear at the precise location where the QR code is detected, rather than just somewhere in the AR space. If this is possible, could you point me in the right direction or recommend the best approach to achieve this? Thank you for your help!

I need to loop my videoMaterial and I don't know how to make it happen in my code. I have included an image of my videoMaterial code. Any help making this happen with be greatly appreciated. Thank you, Christopher

I'm developing an AR application for the iPad pro where the primary purpose is to overlay 3D design data on top of production parts. For alignment, we are using Vuforia (model targets) which work really well locally. The further the device is moved from the point of original alignment, we are seeing quite a bit of overlay error (drift?). My primary questions are: Are there any best practices to stabilize frame-to-frame tracking when using model targets? We are noticing drift as soon as the device starts moving (the drift appears to occur specifically in the direction the device is moving). After about 15 feet of movement, we are observing about 3-6" of overlay error These use cases can be over 100 feet long. In order to reset drift, we understand we'll need multiple alignment points (model targets) along the way. Is there a standard/best practice for this? Ex: have a new alignment point every x-feet? We are using plane anchors to set our alignment. Typically we attach it to the nearest plane; however, the anchor point can be very far away (the origin of the model, which often is not near where the virtual content is). Could this be the issue? The anchor is far from the plane that we attach it too. Would moving the anchor closer to the plane we attach it too improve stability? After a few steps, the plane we originally attach too will be out of FoV anyway. Thanks in advance!

I am creating a vision pro app with a 3D model, it has a mesh hierarchy of head, hands, feet etc. I want the character to look towards the camera, but am not able to access head of character through sceneKit nor reality kit. when I try to print names of the child meshes, it only prints till the character, it does iterate through all the body parts. Can anyone help?

Hello! I'm a developer of Ping Pong for Apple Vision Pro (Ping Pong Club). I'm experiencing an issues with collisions between ball and paddle. Sometimes the ball just unexpectedly flying away like it has been hit to hard. I believe this is happening because hand anchors are jittering (ping pong paddle has hand anchor component) and at the time of collision unnecessary micro motion produced. I've build a demo app to demonstrate that: https://drive.google.com/file/d/1gBh-DsXuVZdvDrrD7gJcbJ_hg7tvVKUV/view?usp=share_link Video: https://drive.google.com/file/d/1poPbsJdBz87edqrWIfBt1eSVzfm5CTek/view?usp=sharing Is there a way to add some threshold to prevent jittering?