Discuss Spatial Computing on Apple Platforms.

Posts under General subtopic

Post

Replies

Boosts

Views

Activity

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!
0
0
323
Sep ’25
VisionOS 2 - Passthrough in screen capture
I'm trying to develop an app that broadcasts what the user sees (priorly we were using main camera access) but now we'd like to investigate and try with this option. I have set up the BroadcastExtension, I've added the picker, I click on my button, I can see my broadcast extension in the options list in the control center, once I click start, it stops after 1 second more or less. I'm not able to get anything in the console from my Sample Handler (prints or logs or anything). I can see however in the console.app some misleading information (one after the other): [INFO] -[RPRecordingManager getSystemBroadcastExtensionInfo:]_block_invoke:1333 Extension has passthrough license [INFO] -[RPRecordingManager getSystemBroadcastExtensionInfo:]_block_invoke:1336 Extension does not have passthrough license We have the entreprise license, the capability and I did add the capability on the extension target as well.
0
0
189
3w
Need to rotate child of a 3D mesh
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?
1
0
177
Sep ’25
Implementing Foveated Streaming with Apple Vision Pro
Hello, Want to understand what's the current state for developing for Apple Vision Pro? I want to stream a video from a remote server in realtime. It is a video stream and can't download it. I want to stream a low quality stream and high res stream. The server will only send the "box" where user is looking at. Are there any API to track where the user is looking at in the experience? Thanks,
1
0
644
1w
Presenting images in RealityKit sample No Longer Builds
After updating to the latest visionOS beta, visionOS 26 Beta 4 (23M5300g) the ‘Presenting images in RealityKit’ sample from the following link no longer builds due to an error. https://developer.apple.com/documentation/RealityKit/presenting-images-in-realitykit Expected / Previous: Application builds and runs on device, working as described in the documentation. Reality: Application builds, but does not run on device due to an error (shown in screenshot) “Thread 1: EXC_BAD_ACCESS (code=1, address=0xb)”. The application still runs on the simulator, but not on device. When launching the app from Xcode, it builds and installs correctly but hangs due to the respective error. When loading the app from the Home Screen, the app does not load, and immediately returns to the Home Screen. This Xcode project previously ran with no changes to code - the only change was updating the visionOS system software to the latest version. visionOS 26 Beta 4 (23M5300g) Is anyone else experiencing this issue?
4
0
216
Aug ’25
How to configure Spatial Audio on a Video Material?, Compile error.
I've tried following apple's documentation to apply a video material on a Model Entity, but I have encountered a compile error while attempting to specify the Spatial Audio type. It is a 360 video on a Sphere which plays just fine, but the audio is too quiet compared to the volume I get when I preview the video on Xcode. So I tried tried to configure audio playback mode on the material but it gives me a compile error: "audioInputMode' is unavailable in visionOS audioInputMode' has been explicitly marked unavailable here RealityFoundation.VideoPlaybackController.audioInputMode)" https://developer.apple.com/documentation/realitykit/videomaterial/ Code: let player = AVPlayer(url: url) // Instantiate and configure the video material. let material = VideoMaterial(avPlayer: player) // Configure audio playback mode. material.controller.audioInputMode = .spatial // this line won’t compile. VisionOS 2.4, Xcode 16.4, also tried Xcode 26 beta 2. The videos are HEVC MPEG-4 codecs. Is there any other way to do this, or is there a workaround available? Thank you.
2
0
240
Jul ’25
How to create a MultiplayerDelegate and use TabletopNetworkSession features?
When building a multiplayer Tabletop game, the documentation includes how to attach a custom TabletopNetworkSessionCoordinator, which could be used in addition to TabletopGame.MultiplayerDelegate. But so far, we have been unable to create these types of custom coordinators or have a delegate that works. Our current setup with our generic GroupActivity works by sending the session to TabletopGame's coordinateWithSession method (like in the current sample project), but we didn't find a way to access and control, for example, the arbiter, seats, player events, among other features mentioned on https://developer.apple.com/documentation/tabletopkit/tabletopnetworksession. Is correct to expect having access to the participants, messenger, or journal without having to maintain a parallel coordinator?   possibly we are missing something here; any suggestions?
2
0
241
Apr ’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
3
0
135
Jun ’25
A Summary of the WWDC25 Group Lab - visionOS
At WWDC25 we launched a new type of Lab event for the developer community - Group Labs. A Group Lab is a panel Q&A designed for a large audience of developers. Group Labs are a unique opportunity for the community to submit questions directly to a panel of Apple engineers and designers. Here are the highlights from the WWDC25 Group Lab for visionOS. I saw that there is a new way to add SwiftUI View attachments in my RealityView, what advantages does this have over the old way? Attachments can now be added directly to your entities with ViewAttachmentComponent. The removes the need to declare your attachments upfront in your RealityView initializer and then add those attachments as child entities. The new approach provides greater flexibility. Canyon Crosser and Petite Asteroids both utilize the new approach. ManipulationComponent looks really cool! Right now my app has a series of complicated custom gestures. What gestures does it handle for me exactly, and are there any situations where I should prefer my own custom gestures? ManipulationComponent provides natural interaction with virtual objects. It seamlessly handles translation and rotation. You can easily add manipulation to a SwiftUI view like Model3D with the manipulable view modifier. The new Object Manipulation API is great for most apps, and is a breeze to implement, but sometimes you might want a more custom feel, and that’s ok! Custom gestures are still fully supported for that scenario. I saw that there is a new API to also access the right main camera. What can I do with this? Correct, in visionOS 26, you can access the left and right main cameras. You can even access them simultaneously as a stereo pair. Camera access still requires a managed entitlement and an enterprise license, see Accessing the main camera for more details about those requirements. More computer vision and machine learning use-cases are unlocked with access to both cameras, we are excited to see what you will do! What do I need to do to add spatial accessory input for my app? First, use the GameController framework to establish a connection with the spatial accessory, and then listen for events from the controller. Then, you can use either RealityKit, ARKit, or a combination of both to track the accessory, anchor virtual content to it, and fine tune the accessory interaction with the content in your app. For more details, check out Discovering and tracking spatial game controllers and styli. By far, the most difficulty with implementing visionOS apps is SwiftUI window management…placing, opening, closing, etc. Are there any improvements to window management in visionOS 26? Yes! We recommend watching Set the scene with SwiftUI in visionOS. You can use the defaultLaunchBehavior to choose whether a particular window is presented (or suppressed) at launch. You can also prevent a window like a secondary toolbar from launching as the initial window using .restorationBehavior(.disabled). Adopting best practices for persistent UI provides a great overview of SwiftUI window management on visionOS. As for placing windows, there is still no API for an app to specify the placement of its windows other than relative placement. If that is a feature you are interested in, please file an enhancement request for it using Feedback Assistant! How to get access to the Enterprise API? First, request the entitlement and license through your Apple Developer or enterprise account. Once these have been granted, include the license and entitlement in your project. Then you can build, test, and distribute as an in-house app.
4
0
320
Jul ’25
Overlaying SwiftUI content with transparency in front of RealityView
Following up on my previous question here: https://developer.apple.com/forums/thread/774262 Having solved the clipping problem, I am now trying to overlay some content in front of the RealityView. However, it looks like any content with transparency does not render in front of the RealityView, while opaque views seem to work; placing content with transparency like glassBackgroundEffect() behind the RealityView in a ZStack causes the entire window to flicker. Additionally, my SwiftUI attachment placed in front of the stereoscopic image plane are invisible if the user look at it straight at 90 degrees. However, if the user look at it from increasing angles from the sides, the attachment gradually turns visible again. Are these behaviors expected? What is a recommended approach to overlay content in front of a RealityView? Thanks!
1
0
391
Feb ’25
How to mix Animation and IKRig in RealityKit
I want an AR character to be able to look at a position while still playing the characters animation. So far, I managed to manually adjust a single bone rotation using skeletalComponent.poses.default = Transform( scale: baseTransform.scale, rotation: lookAtRotation, translation: baseTransform.translation ) which I run at every rendering update, while a full body animation is running. But of course, hardcoding single joints to point into a direction (in my case the head) does not look as nice, as if I were to run some inverse cinematic that includes, hips + neck + head joints. I found some good IKRig code in Composing interactive 3D content with RealityKit and Reality Composer Pro. But when I try to adjust rigs while animations are playing, the animations are usually winning over the IKRig changes to the mesh.
1
0
510
Aug ’25
Hidden window/volume system overlays in Full Space
When I show a window while a sky sphere is shown, the handles to drag/close/resize the window are hidden. The colliders still work, so they are there, but only the visuals are hidden. I already know from another project, that this also happens to volumes. They only appear once you get closer to the window or if the sky sphere gets removed. Is this a known issue or is there a fix for that? .persistentSystemOverlays(.visible)does not fix it Xcode 16.3.0 Beta, visionOS 2.4
5
0
348
Mar ’25