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ARKit Eye Tracking Calibration Issues - Word-Level Reading Tracking Feasibility
Hi Apple Developer Community, I'm developing an eye-tracking application using ARKit's ARFaceTrackingConfiguration and ARFaceAnchor.blendShapes for gaze detection using Xcode. I'm experiencing several calibration and accuracy issues and would appreciate insights from the community. Current Implementation Using ARFaceAnchor.blendShapes (.eyeLookUpLeft, .eyeLookDownLeft, .eyeLookInLeft, .eyeLookOutLeft, etc.) Implementing custom sensitivity curves and smoothing algorithms Applying baseline correction and coordinate mapping Using quadratic regression for calibration point mapping Issues I'm Facing 1. Calibration Mismatch Red dot position doesn't align with where I'm actually looking Significant offset between intended gaze point and actual cursor position Calibration seems to drift or become inaccurate over time 2. Extreme Eye Movement Requirements Need to make exaggerated eye movements to reach screen edges/corners Natural eye movements don't translate to proportional cursor movement Difficulty reaching certain screen regions even with calibration 3. Sensitivity and Stability Issues Cursor jitters or jumps around when looking at center Too much sensitivity to micro-movements Inconsistent behavior between calibration and normal operation 4. I also noticed that tracking on calibration screen as well as tracking on reading screen works better as expected when head movement is there, but I do not want much head movement. I want tracking with normal eye movement while reading an Ebook. Primary Question: Word-Level Eye Tracking Feasibility Is word-level eye tracking (tracking gaze as users read through individual words in an ebook) technically feasible with current iPhone/iPad hardware? I understand that Apple's built-in eye tracking is primarily an accessibility feature for UI navigation. However, I'm wondering if the TrueDepth camera and ARKit's eye tracking capabilities are sufficient for: Tracking natural reading patterns (left-to-right, line-by-line progression) Detecting which specific words a user is looking at Maintaining accuracy for sustained reading sessions (15-30 minutes) Working reliably across different users and lighting conditions Questions for the Community Hardware Limitations: Are iPhone/iPad TrueDepth cameras capable of the precision needed for word-level tracking, or is this beyond current hardware capabilities? Calibration Best Practices: What calibration strategies have worked best for accurate gaze mapping? How many calibration points are typically needed? Reading-Specific Challenges: Are there particular challenges when tracking reading behavior vs. general gaze tracking? Alternative Approaches: Are there better approaches than ARKit blend shapes for this use case? Current Setup Devices: iPhone 14 Pro iOS Version: iOS 18.3 ARKit Version: Latest available Any insights, experiences, or technical guidance would be greatly appreciated. I'm particularly interested in hearing from developers who have worked on similar eye tracking applications or have experience with the limitations and capabilities of ARKit's eye tracking features. Thank you for your time and expertise!
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718
Oct ’25
Depth matrix accuracy with the iPhone 14 Pro and Lidar
Hello Community, I’m currently working with the sample code “CapturingDepthUsingTheLiDARCamera” and using it to capture the depth map of an image taken with the iPhone 14 Pro. From this depth map, I generate a point cloud using the intrinsic camera parameters. I've noticed that objects not facing the camera directly appear distorted in the resulting point cloud. For example: An object with surfaces that are perpendicular to each other appears with a sharper angle in the point cloud — around 60° instead of 90°. My question is: Is this due to the general accuracy limitations of the LiDAR sensor? Or could it be related to the sample code? To obtain the depth map, I’m using: AVCapturePhoto.depthData.converting(toDepthDataType: kCVPixelFormatType_DepthFloat32) Thanks in advance for your help!
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99
Apr ’25
How to Move and Rotate WindowGroup with Code in Xcode
当我进入混合空间时,出现一个模型,但模型后面有一个 windowGroup,无法完全查看。如果我想点击进入 mix 空间,我需要使用代码将 windowGroup 移动到另一个位置,而不是手动移动 ![](“https://developer.apple.com/forums/content/attachment/0471ead0-4c74-43a7-9ecc-12e67e81cec6” “title=WechatIMG31.jpg;宽度=915;高度=777”)
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60
Mar ’25
Vision Pro stucks on "Retrieving configuration"
Hi, after upgrading to 2.4.1 (from 1.0) my vision stucks on "Retrieving configuration" screen. Apple Store didn't support my case since it has been sold in USA and the product isn't still present in italian market. I don't have dev strap, how can I manage the issue? Thank you
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111
May ’25
How to add visual thickness to a glass background view
Hi guys, In visionOS, when using a ZStack decorated with .glassBackgroundEffect(), you can see the 3D glass background from the front, but when viewed from the side, the view appears to have no thickness. However, I noticed that in an app built by Apple, when viewing a glass background view from the side, it appears to have thickness. I tried adding .frame(depth:) to a glass background view, but it appears as two separate layers spaced by the depth value. My question is: Is there a view modifier that adds visual thickness to a glass background view, as shown in the picture? Or, if not, how should I write a custom view modifier to achieve this effect? Thanks!
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102
May ’25
Hand Tracking Latency When UITextView Becomes Active in Vision Pro Immersive Space
I'm placing sphere at finger tip and updating its position as hand move. Finger joint tracking functions correctly, but I’ve observed noticeable latency in hand tracking updates whenever a UITextView becomes active. This lag happens intermittently during app usage, lasting about 5–10 seconds, after which the latency disappears and the sphere starts following the finger joints immediately. When I open the immersive space for the first time, the profiler shows a large performance spike upto 328%. After that, it stabilizes and runs smoothly. Note: I don’t observe any lag when CPU usage spikes to 300% (upon immersive view load) yet the lag still occurs even when CPU usage remains below 100%. I’m using the following code for hand tracking: private func processHandTrackingUpdates() async { for await update in handTracking.anchorUpdates { let handAnchor = update.anchor if handAnchor.isTracked { switch handAnchor.chirality { case .left: leftHandAnchor = handAnchor updateHandJoints(for: handAnchor, with: leftHandJointEntities) case .right: rightHandAnchor = handAnchor updateHandJoints(for: handAnchor, with: rightHandJointEntities) } } else { switch handAnchor.chirality { case .left: leftHandAnchor = nil hideAllJoints(in: leftHandJointEntities) case .right: rightHandAnchor = nil hideAllJoints(in: rightHandJointEntities) } } await MainActor.run { handTrackingData.processNewHandAnchors( leftHand: self.leftHandAnchor, rightHand: self.rightHandAnchor ) } } } And here’s the function I’m using to update the joint positions: private func updateHandJoints( for handAnchor: HandAnchor, with jointEntities: [HandSkeleton.JointName: Entity] ) { guard handAnchor.isTracked else { hideAllJoints(in: jointEntities) return } // Check if the little finger tip and intermediate base are both tracked. if let tipJoint = handAnchor.handSkeleton?.joint(.littleFingerTip), let intermediateBaseJoint = handAnchor.handSkeleton?.joint(.littleFingerIntermediateTip), tipJoint.isTracked, intermediateBaseJoint.isTracked, let pinkySphere = jointEntities[.littleFingerTip] { // Convert joint transforms to world space. let tipTransform = handAnchor.originFromAnchorTransform * tipJoint.anchorFromJointTransform let intermediateBaseTransform = handAnchor.originFromAnchorTransform * intermediateBaseJoint.anchorFromJointTransform // Extract positions from the transforms. let tipPosition = SIMD3<Float>(tipTransform.columns.3.x, tipTransform.columns.3.y, tipTransform.columns.3.z) let intermediateBasePosition = SIMD3<Float>(intermediateBaseTransform.columns.3.x, intermediateBaseTransform.columns.3.y, intermediateBaseTransform.columns.3.z) // Calculate the midpoint. let midpointPosition = (tipPosition + intermediateBasePosition) / 2.0 // Position the sphere at the midpoint and make it visible. pinkySphere.isEnabled = true pinkySphere.transform.translation = midpointPosition } else { // If either joint is not tracked, hide the sphere. jointEntities[.littleFingerTip]?.isEnabled = false } // Update the positions of all other hand joint spheres. for (jointName, entity) in jointEntities { if jointName == .littleFingerTip { // Already handled the pinky above. continue } guard let joint = handAnchor.handSkeleton?.joint(jointName), joint.isTracked else { entity.isEnabled = false continue } entity.isEnabled = true let jointTransform = handAnchor.originFromAnchorTransform * joint.anchorFromJointTransform entity.transform.translation = SIMD3<Float>(jointTransform.columns.3.x, jointTransform.columns.3.y, jointTransform.columns.3.z) } } I’ve attached both a profiler trace and a video recording from Vision Pro that clearly demonstrate the issue. Profiler: https://drive.google.com/file/d/1fDWyGj_fgxud2ngkGH_IVmuH_kO-z0XZ Vision Pro Recordings: https://drive.google.com/file/d/17qo3U9ivwYBsbaSm26fjaOokkJApbkz- https://drive.google.com/file/d/1LxTxgudMvWDhOqKVuhc3QaHfY_1x8iA0 Has anyone else experienced this behavior? My thought is that there might be some background calculations happening at the OS level causing this latency. Any guidance would be greatly appreciated. Thanks!
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334
Sep ’25
Cannot reassign worldTracking / planeDetection providers in my PlacementManager when switching environments
Environment Xcode: 16.2 VisionOS SDK 2.4 Swift 6.1 Targets: Apple Vision Pro (immersive space) Frameworks: ARKit, RealityKit, SwiftUI What I’m Trying to Do I have a view-model class PlacementManager that holds two AR providers: private var worldTracking: WorldTrackingProvider private var planeDetection: PlaneDetectionProvider I want to dynamically replace these providers in a setEnvironment(_:) method (so I can save/clear a JSON scene and restart ARKit). What’s Happening If I declare them as : private let worldTracking = WorldTrackingProvider() private let planeDetection = PlaneDetectionProvider() I get compile-errors when I later do: self.worldTracking = newWorldTracking // Cannot assign to property: 'worldTracking' is a 'let' constant If I change them to un-initialized vars: private var worldTracking: WorldTrackingProvider private var planeDetection: PlaneDetectionProvider then in my init() I get: self used in property access 'worldTracking' before all stored properties are initialized Code snipet @Observable final class PlacementManager : ObservableObject { private var worldTracking: WorldTrackingProvider private var planeDetection: PlaneDetectionProvider // … other props … @MainActor init() { // error: self.worldTracking used before init… planeAnchorHandler = PlaneAnchorHandler(rootEntity: root) persistenceManager = PersistenceManager( worldTracking: worldTracking, rootEntity: root ) // … } @MainActor func setEnvironment(env: Environnement) async { let newWorldTracking = WorldTrackingProvider() let newPlaneDetection = PlaneDetectionProvider() try await appState!.arkitSession.run( [ newWorldTracking, newPlaneDetection ] ) self.worldTracking = newWorldTracking self.planeDetection = newPlaneDetection // … } } What I’ve Tried Giving them default values at declaration (= WorldTrackingProvider()) Initializing them at the top of init() before any use Passing the new providers into arkitSession.run(...) My Question What is the recommended Swift-style pattern to declare and reassign these ARKit provider properties so that: They’re fully initialized before use in init(), and I can swap them out later in setEnvironment(...) without compiler errors? Any pointers (or links to forum threads / docs) would be greatly appreciated!
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116
May ’25
visionOS 26 - Rendering Issues related to Transparency
Summary After updating to visionOS 26, we’ve encountered severe transparency rendering issues in RealityKit that did not exist in visionOS 2.6 and earlier. These regressions affect applications that dynamically control scene opacity (via OpacityComponent). Our app renders ultra-realistic apartment environments in real time, where users can walk or teleport inside 3D spaces. When the user moves above a speed threshold, we apply a global transparency effect to prevent physical collisions with real-world objects. Everything worked perfectly in visionOS 2.6 — the problems appeared only after upgrading to 26. Scene Setup Overview The environment consists of multiple USDZ models (e.g., architecture, rooms, furniture). We manage LODs manually for performance (e.g., walls and floors always visible in full-res, while rooms swap between low/high-res versions based on user position and field of view). Transparency is achieved using OpacityComponent, applied dynamically when the user moves. Some meshes (e.g., portals to skyboxes, glass windows) use alpha materials We also use OcclusionMaterials to prevent things to be seen through walls when scene is transparent Observed Behavior by Scenario (I can share a video showing the results of each scenario if needed.) Scenario 1 — Severe Flickering (Root Opacity) Setup: OpacityComponent applied to the root entity NO ModelSortGroupComponent used Symptoms: Strong flickering when transparency is active Triangles within the same mesh render at inconsistent opacity levels Appears as if per-triangle alpha sorting is broken Workaround: Moving the OpacityComponent from the root to each individual USDZ entity removes the per-triangle flicker Pros: No conflicts with portals or alpha materials Scenario 2 — Partially Stable, But Alpha Conflicts Setup: OpacityComponent applied per USDZ entity ModelSortGroupComponent(planarUIAlwaysBehind) applied to portal meshes Other entities have NO ModelSortGroupComponent Symptoms: Frequent alpha blending conflicts: Transparent surfaces behind other transparent surfaces flicker or disappear Example: Wine glasses behind glass doors — sometimes neither is rendered, or only one Even opaque meshes behind glass flicker due to depth buffer confusion Alpha materials sometimes render portals or the real world behind them, ignoring other geometry entirely Analysis: Appears related to internal changes in alpha sorting or depth pre-pass behavior introduced in visionOS 26 Pros: Most stable setup so far Cons: Still unreliable when OpacityComponent is active Scenario 3 — Layer Separation Attempt (Regression) Setup: Same as Scenario 2, but: Entities with alpha materials moved to separate USDZs Explicit ModelSortGroupComponent order set (alpha surfaces rendered last) Symptoms: Transparent surfaces behind other transparent surfaces flicker or disappear Depth is completely broken when there's a large transparent surface Alpha materials sometimes render portals or the real world behind them, ignoring other geometry entirely Workaround Attempt: Re-ordering and further separating models did not solve it Pros: None — this setup makes transparency unusable Conclusion There appears to be a regression in RealityKit’s handling of transparency and sorting in visionOS 26, particularly when: OpacityComponent is applied dynamically, and Scenes rely on multiple overlapping transparent materials. These issues did not exist prior to 26, and the same project (no code changes) behaves correctly on previous versions. Request We’d appreciate any insight or confirmation from Apple engineers regarding: Whether alpha sorting or opacity blending behavior changed in visionOS 26 If there are new recommended practices for combining OpacityComponent with transparent materials If a bug report already exists for this regression Thanks in advance!
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185
Nov ’25
Logitech Muse: OS-level support?
I've been experimenting with the Muse pen and understand that it can be accessed by my app through a SpatialTrackingSession, but is there any current or planned support for devices like this as for general UI input like game controllers are? For example, using the button as a tap analogue for SwiftUI views.
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103
Oct ’25
Accessing LiDAR Depth Data and Scene Reconstruction on Apple Vision Pro
Hello, I'm developing a visionOS application for Apple Vision Pro that aims to scan unknown physical objects, capture their 3D data (such as meshes or point clouds), and export them as 3D models. Ideally, I'd also like to visualize these reconstructions in real-time within the headset. This functionality is similar to what's available in Reality Composer on iPad and iPhone, but I'm seeking to implement it natively on Vision Pro. I've reviewed the visionOS documentation but haven't found clear guidance on accessing LiDAR depth data or performing scene reconstruction. Specifically, I'm interested in: 1.Accessing LiDAR or depth data from Vision Pro's sensors. 2.Utilizing ARKit's scene reconstruction capabilities on visionOS. 3.Exporting captured 3D data as models (e.g., USDZ or OBJ formats). Are there APIs or frameworks in visionOS that support these features?
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128
May ’25
多相机切换时画质参数差异显著
切换后两者的亮度、色彩饱和度、对比度等画质参数差距较大,导致画面视觉体验割裂,破坏直播连贯性,影响用户观看沉浸感。 期望 "· 对标常规直播单反相机的画质基准,优化 Vision Pro 的画面亮度、色彩还原能力; · 提供设备端或配套软件的画质自定义调节功能(亮度、对比度、色温等),支持直播前手动校准,确保与单反相机画面风格一致。"
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2w
Help Configuring Unity for Immersive VR on Vision Pro with Pinch Teleport
How do I configure a Unity project for a fully immersive VR app on Apple Vision Pro using Metal Rendering, and add a simple pinch-to-teleport-where-looking feature? I've tried the available samples and docs, but they don't cover this clearly (to me). So far, I've reviewed Unity XR docs, Apple dev guides, and tutorials, but most emphasize spatial apps. Metal examples exist but don't include teleportation. Specifically: visionOS sample "XRI_SimpleRig" – Deploys to device/simulator, but no full immersion or teleport. XRI Toolkit sample "XR Origin Hands (XR Rig)" – Pinch gestures detect, but not linked to movement. visionOS "XR Plugin" sample "Metal Sample URP" – Metal setup works, but static scene without locomotion. I'm new in Unity XR development and would appreciate a simple, standalone scene or document focused only on the essentials for "teleport to gaze on pinch" in VR mode—no extra features. I do have some experience in unreal, world toolkit, cosmo, etc from the 90's and I'm ok with code. Please include steps for: Setting up immersive VR (disabling spatial defaults if needed). Integrating pinch detection with ray-based teleport. Any config changes or basic scripts. Project Configuration: Unity Editor Version: 6000.2.5f1.2588.7373 (Revision: 6000.2/staging 43d04cd1df69) Installed Packages: Apple visionOS XR Plugin: 2.3.1 AR Foundation: 6.2.0 PolySpatial XR: 2.3.1 XR Core Utilities: 2.5.3 XR Hands: 1.6.1 XR Interaction Toolkit: 3.2.1 XR Legacy Input Helpers: 2.1.12 XR Plugin Management: 4.5.1 Imported Samples: Apple visionOS XR Plugin 2.3.1: Metal Sample - URP XR Hands 1.6.1 XR Interaction Toolkit 3.2.1: Hands Interaction Demo, Starter Assets, visionOS Build Platform Settings: Target: Apple visionOS App Mode: Metal Rendering with Compositor Services Selected Validation Profiles: visionOS Metal Documentation: Enabled Xcode Version: 26.01 visionOS SDK: 26 Mac Hardware: Apple M1 Max Target visionOS Version: 20 or 26 Test Environment: Model: Apple Vision Pro, visionOS 26.0.1 (23M341), Apple M1 Max No errors in builds so far; just missing the desired functionality. Thanks for a complete response with actionable steps.
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232
Oct ’25
onWorldRecenter memory leak and duplicate callbacks in ImmersiveSpace
Posting this here in case this information is helpful to other developers: As of visionOS 26.3 beta 1, onWorldRecenter has two significant issues: (FB21557639) Memory Leak: When onWorldRecenter is assigned to a RealityView within an ImmersiveSpace, it appears to retain a strong reference to the view's internal SwiftUI context. When the immersive space is dismissed, the view's @State objects will not be deallocated. Also, each time the immersive space view's body is executed, additional state storage will be allocated and leaked. Multiple Callbacks: When the user long-presses the Digital Crown, the onWorldRecenter closure will be called multiple times, once for each past view body execution, including those of immersive space views that have been previously dismissed. Although these issues seem to be most prevalent when onWorldRecenter is used with an ImmersiveSpace, they may also occur in the context of a WindowGroup under certain circumstances. It's possible to work around this problem by moving onWorldRecenter to an empty overlay view within the app's primary WindowGroup and forwarding the world recenter events to ImmersiveSpace views through a notification system, coupled with a debouncer as an extra precaution.
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248
1d
VisionPro MRApp issue: location reset
We use Unity6+VisonOS2.2 to develop an MR Application. App Mode: RealityKit with PolySpatial, In the actual test, we found that when my moving position is more than 80~100 meters away from the starting position of the application, my current position will be reset to Vector.zero, which will cause my application experience to be very bad. Is anyone experiencing the same problem? Is there a solution?
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225
Jan ’25