My app for framing and arranging pictures from Photos on visionOS allows users to write the arrangements they create to .reality files using RealityKit entity.write(to:) that they then display to customers on their websites. This works perfectly on visionOS 2, but fails with a fatal protection error on visionOS 26 beta 1 and beta 2 when write(to:) attempts to write to its internal cache:
2025-06-29 14:03:04.688 Failed to write reality file Error Domain=RERealityFileWriterErrorDomain Code=10 "Could not create parent folders for file path /var/mobile/Containers/Data/Application/81E1DDC4-331F-425D-919B-3AB87390479A/Library/Caches/com.GeorgePurvis.Photography.FrameItVision/RealityFileBundleZippingTmp_A049685F-C9B2-479B-890D-CF43D13B60E9/41453BC9-26CB-46C5-ADBE-C0A50253EC27."
UserInfo={NSLocalizedDescription=Could not create parent folders for file path /var/mobile/Containers/Data/Application/81E1DDC4-331F-425D-919B-3AB87390479A/Library/Caches/com.GeorgePurvis.Photography.FrameItVision/RealityFileBundleZippingTmp_A049685F-C9B2-479B-890D-CF43D13B60E9/41453BC9-26CB-46C5-ADBE-C0A50253EC27.}
Has anyone else encountered this problem? Do you have a workaround? Have you filed a feedback?
ChatGPT analysis of the error and my code reports:
Why there is no workaround
• entity.write(to:) is a black box — you cannot override where it builds its staging bundle
• it always tries to create those random folders itself
• you cannot supply a parent or working directory to RealityFileWriter
• so if the system fails to create that folder, you cannot patch it
👉 This is why you see a fatal error with no recovery.
See also feedbacks: FB18494954, FB18036627, FB18063766
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I'm playing about with the hand tracking systems in reality kit / Vision Pro
I thought it would be interesting if I could attach a virtual object to a hand when the hand is gripping (thought it would be fun to attach a basic cylinder to mimic a wand from Harry Potter)
I'm able to detect when the user is gripping but having trouble placing an object as though it's within the hand.
The simplest version of this is using an AnchorEntity pointing to the user's palm which kind of works, but quickly breaks the illusion when you rotate the wrist or hand.
It seems as though I will have to roll my own anchor entity using the various points of the user's hand and I thought calculating some median point between the thumb and little finger tips would be a good start but it's proven a little difficult as we need both rotation and position.
I'm already out of my depth with reality kit and matrices (and thanks to ChatGPT) I have some code, but as soon as I apply the position manually (as opposed to a hand anchor entity) it fails to render on the user's hand.
It feels like this should already have been something someone has looked in to, any ideas on what might be the issue here?
Note: HandTrackingSystem.handTracking is a HandTrackingProvider()
guard let anchors = HandTrackingSystem.handTracking.latestAnchors.leftHand else {
return
}
if
let thumb = anchors.handSkeleton?.joint(.thumbTip),
let little = anchors.handSkeleton?.joint(.littleFingerTip)
{
let thumbPos = simd_make_float3(thumb.anchorFromJointTransform.columns.3)
let littlePos = simd_make_float3(little.anchorFromJointTransform.columns.3)
let midPos = (thumbPos + littlePos) / 2
let direction = normalize(littlePos - thumbPos)
let rotation = simd_quatf(from: [0, 1, 0], to: direction)
wandEntity.transform.translation = midPos
wandEntity.transform.rotation = rotation
content.add(wandEntity)
}
Hi, we would like to create something where you can open multiple volumetric windows and place them in a room, our biggest issue is that we want these windows to be persistent, so when I close and reopen the app, the windows to be in the same position. We can't use immersive spaces because we also want to have the possibility to access the shared space.
Is it possible with the current features and capabilities to do that? If yes do you have some advices how can we achieve this?
The alternative is if is it possible to open the virtual display in immersive spaces or if we have the possibility to implement our own virtual display.
In WWDC25 session What’s new for the spatial web, the presenter showed creating an immersive environment for a web page by adding to the page's HEAD section
<link rel="spatial-backdrop" href="office.usdz" environmentmap="lighting.hdr">
My first attempt failed, and I am trying to track down why.
Before I search all the potential failure paths, I wanted to ask the community,
Is this feature available in the latest visionOS 26 beta?
I haven't seen anyone talk about their use of the feature yet.
Topic:
Spatial Computing
SubTopic:
General
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
With Xcode 26, loading ressources with RealityKit is extremely slow.
Here my project takes almost 50 seconds to load.
I also get multiple Hang detected messages in the console:
When I uncheck "Debug executable" in the schema, the same project loads in 2 seconds.
I'm using RealityKit asynchronous loading:
private static func loadFromRealityComposerPro(
named entityName: String,
fromSceneNamed sceneName: String
) async -> Entity? {
var entity: Entity?
do {
let scene = try await Entity(
named: sceneName,
in: visionPetsContentBundle
)
entity = scene.findEntity(named: entityName)
} catch {
print(
"Error loading \(entityName) from scene \(sceneName): \(error.localizedDescription)"
)
}
return entity
}
Anyone having the same problem?
Topic:
Spatial Computing
SubTopic:
General
The Section struct only publicly makes the center property available, but this is a SIMD3 that doesn't seem to line up with the rest of the model. All other objects have a 4x4 transform matrix that accurately gives each position and rotation.
When inspecting a Section in the debugger, many more properties are visible such as polygon and transform. Why are these not visible? The transform in particular seems necessary to make any sort of use of the Sections.
In an earlier beta, BillboardComponent had rotationAxis and upDirection properties which allowed more fine-grained control of how an entity rotates towards the camera.
Currently, it is only possible to orient the z axis of the entity.
Looking at the robot in the documentation, the rotation of its z axis causes its feet to lift off the ground.
Before, it was possible to restrain the rotation to one axis (y, for example) so that the robot's feet stayed on the ground with
billboard.upDirection = [0, 1, 0]
billboard.rotationAxis = [0, 1, 0]
Is there an alternative way to achieve this? Are these properties (or similar) coming back?
This modifier in visionOS 2.5 works perfectly with LazyVgrid inside a Stack in ScrollView:
.hoverEffect { effect, isActive, _ in
effect.scaleEffect(isActive ? 1.1 : 1.0)
But the grid does not scroll in visionOS 26 beta 1 unless the scaleEffect is commented out.
FB17941468
I have been experimenting with the Hello World sample app from https://developer.apple.com/documentation/visionos/world and I came across behavior that appears inconsistent with user-facing documentation describing the device controls at https://support.apple.com/en-gb/guide/apple-vision-pro/tan1e2a29e00/visionos
I tried pressing simulator's "Home" button while "Objects in Orbit" immersive space was presented alongside with the main application window. According to user documentation, pressing Digital Crown should take the user directly to Home View. In my test a single press only dismissed the immersive space, I needed another press to "exit" the app and go to Home View.
Is this behavior expected? I am assuming that "Home" button in the simulator behaves as if the user pressed Digital Crown on the device, I don't have access to the actual hardware.
I found some snapshot API in developer documents, like blows:
RealityKit / Views and attachments / ARView / /snapshot(saveToHDR:completion:)
SceneKit / SCNView / snapshot()
Is there a similar API in visionOS?and if not, how can I implement snapshot for realityview and usdz?
When I've made an animated UDSZ, at what framerate will the animation be rendered in QuickLook? Is it the same across all devices? (iPhone, Apple Vision Pro, etc.) and viewing environments? (QuickLook, inside an ARView, etc.)
Suppose I export my file at 30fps and the device draws at 60fps, does the device interpolate between frames automatically, animate at a lower frame rate, or play it at twice the speed? What if it were 24fps?
My primary concern with understanding frame rates is a bit of trouble I've had making perfectly looping animations. There always seems to be the slightest stutter between iterations.
Thanks in advance for any insights you're able to provide!
I am trying to get the new PresentationComponent working in VisionOS26 as seen in this WWDC video:
https://developer.apple.com/videos/play/wwdc2025/274/?time=962 (18:29 minutes into video)
Here is some other example code but it doesn't work either: https://stepinto.vision/devlogs/project-graveyard-devlog-002/
My simple Text view (that I am adding as a PresentationComponent) does not appear in my RealityView even though the entity is found. Here is a simple example built from an Xcode immersive view default project:
struct ImmersiveView: View {
@Environment(AppModel.self) var appModel
var body: some View {
RealityView { content in
// Add the initial RealityKit content
if let immersiveContentEntity = try? await Entity(named: "Immersive", in: realityKitContentBundle) {
content.add(immersiveContentEntity)
if let materializedImmersiveContentEntity = try? await Entity(named: "Test", in: realityKitContentBundle) {
content.add(materializedImmersiveContentEntity)
var presentation = PresentationComponent(
configuration: .popover(arrowEdge: .bottom),
content: Text("Hello, World!")
.foregroundColor(.red)
)
presentation.isPresented = true
materializedImmersiveContentEntity.components.set(presentation)
}
}
}
}
}
Here is the Apple reference: https://developer.apple.com/documentation/realitykit/presentationcomponent
My VisionOS App (Travel Immersive) has two interface windows: a main 2D interface window and a 3D Earth window. If the user first closes the main interface window and then the Earth window, clicking the app icon again will only launch the Earth window while failing to display the main interface window. However, if the user closes the Earth window first and then the main interface window, the app restarts normally.
Below is the code of
import SwiftUI
@main
struct Travel_ImmersiveApp: App {
@StateObject private var appModel = AppModel()
var body: some Scene {
WindowGroup(id: "MainWindow") {
ContentView()
.environmentObject(appModel)
.onDisappear {
appModel.closeEarthWindow = true
}
}
.windowStyle(.automatic)
.defaultSize(width: 1280, height: 825)
WindowGroup(id: "Earth") {
if !appModel.closeEarthWindow {
Globe3DView()
.environmentObject(appModel)
.onDisappear {
appModel.isGlobeWindowOpen = false
}
} else {
EmptyView() // 关闭时渲染空视图
}
}
.windowStyle(.volumetric)
.defaultSize(width: 0.8, height: 0.8, depth: 0.8, in: .meters)
ImmersiveSpace(id: "ImmersiveView") {
ImmersiveView()
.environmentObject(appModel)
}
}
}
At the moment the map kit APls only support non-volumetric maps (i.e. in a window or in a volume, but on a 2D surface).
Is support for 3D volumetric maps in VisionOS in the works? And if so when can we expect it to be available?
I’m currently developing an app for visionOS and working with an ImmersiveSpace. I’ve noticed that the system automatically enforces a safety boundary at approximately 1.5 meters. If the user moves beyond this limit, the content fades out or the system reverts to Passthrough.
Is there any way to disable this boundary or extend its radius?
This app is currently in the experimental/verification phase, and it is intended to be run on a Vision Pro in Developer Mode. Since the primary goal is to test large-scale spatial interactions during development, I am looking for any way—including developer-specific settings or configurations—to bypass or expand this limit.
If there isn't a direct API to change the boundary size, are there any recommended workarounds for testing movement within large environments?
Any insights would be greatly appreciated!
Hi community,
I have a pair of stereo images, one for each eye. How should I render it on visionOS?
I know that for 3D videos, the AVPlayerViewController could display them in fullscreen mode. But I couldn't find any docs relating to 3D stereo images.
I guess my question can be brought up in a more general way: Is there any method that we can render different content for each eye? This could also be helpful to someone who only has sight on one eye.
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?
Hi,
We are trying to port our Unity app from other XR devices to Vision Pro. Thus it's way easier for us to use the Metal rendering layer, fully immersive. And to stay true to the platform, we want to keep the gaze/pinch interaction system.
But we just noticed that, unlike Polyspatial XR apps, VisionOS XR in Metal does not provide gaze info unless the user is actively pinching... Which forbids any attempt to give visual feedback on what they are looking at (buttons, etc).
Is this planned in Apple's roadmap ?
Thanks
When viewing an immersive space and I open a spatial photo in Quick Look, which hides the entire app interface to show the photo. Is there a memory limit? If the inmersive space is not active, the application keep the interface.