Hi,
Toggling a SwiftUI menu in iOS 26 significantly reduces the framerate of an underlying SKView or ARView.
Below are test cases for SpriteKit and RealityKit. I ran these tests on iOS 26.1 Beta using an iPhone 13 (A15 chip). Results were similar on iOS 26.0.1.
Both scenes consist of circles and balls bouncing on the ground. The restitution of the physics bodies is set for near-perfect elasticity, so they keep bouncing indefinitely.
In both SKView and ARView, the framerate drops significantly whenever the SwiftUI menu is toggled. The menu itself is simple and uses standard SwiftUI animations and styling.
SpriteKit
import SpriteKit
import SwiftUI
class SKRestitutionScene: SKScene {
override func didMove(to view: SKView) {
view.contentMode = .center
size = view.bounds.size
scaleMode = .resizeFill
backgroundColor = .darkGray
anchorPoint = CGPoint(x: 0.5, y: 0.5)
let groundWidth: CGFloat = 300
let ground = SKSpriteNode(color: .gray, size: CGSize(width: groundWidth, height: 10))
ground.physicsBody = SKPhysicsBody(rectangleOf: ground.size)
ground.physicsBody?.isDynamic = false
addChild(ground)
let circleCount = 5
let spacing: CGFloat = 60
let totalWidth = CGFloat(circleCount - 1) * spacing
let startX = -totalWidth / 2
for i in 0..<circleCount {
let circle = SKShapeNode(circleOfRadius: 18)
circle.fillColor = .systemOrange
circle.lineWidth = 0
circle.physicsBody = SKPhysicsBody(circleOfRadius: 18)
circle.physicsBody?.restitution = 1
circle.physicsBody?.linearDamping = 0
let x = startX + CGFloat(i) * spacing
circle.position = CGPoint(x: x, y: 150)
addChild(circle)
}
}
override func willMove(from view: SKView) {
self.removeAllChildren()
}
}
struct SKRestitutionView: View {
var body: some View {
ZStack {
SpriteView(scene: SKRestitutionScene(), preferredFramesPerSecond: 120)
.ignoresSafeArea()
VStack {
Spacer()
Menu {
Button("Edit", systemImage: "pencil") {}
Button("Share", systemImage: "square.and.arrow.up") {}
Button("Delete", systemImage: "trash") {}
} label: {
Text("Menu")
}
.buttonStyle(.glass)
}
.padding()
}
}
}
#Preview {
SKRestitutionView()
}
RealityKit
import RealityKit
import SwiftUI
struct ARViewPhysicsRestitution: UIViewRepresentable {
let arView = ARView()
func makeUIView(context: Context) -> some ARView {
arView.contentMode = .center
arView.cameraMode = .nonAR
arView.automaticallyConfigureSession = false
arView.environment.background = .color(.gray)
// MARK: Root
let anchor = AnchorEntity()
arView.scene.addAnchor(anchor)
// MARK: Camera
let camera = Entity()
camera.components.set(PerspectiveCameraComponent())
camera.position = [0, 1, 4]
camera.look(at: .zero, from: camera.position, relativeTo: nil)
anchor.addChild(camera)
// MARK: Ground
let groundWidth: Float = 3.0
let ground = Entity()
let groundMesh = MeshResource.generateBox(width: groundWidth, height: 0.1, depth: groundWidth)
let groundModel = ModelComponent(mesh: groundMesh, materials: [SimpleMaterial(color: .white, roughness: 1, isMetallic: false)])
ground.components.set(groundModel)
let groundShape = ShapeResource.generateBox(width: groundWidth, height: 0.1, depth: groundWidth)
let groundCollision = CollisionComponent(shapes: [groundShape])
ground.components.set(groundCollision)
let groundPhysicsBody = PhysicsBodyComponent(
material: PhysicsMaterialResource.generate(friction: 0, restitution: 0.97),
mode: .static
)
ground.components.set(groundPhysicsBody)
anchor.addChild(ground)
// MARK: Balls
let ballCount = 5
let spacing: Float = 0.4
let totalWidth = Float(ballCount - 1) * spacing
let startX = -totalWidth / 2
let radius: Float = 0.12
let ballMesh = MeshResource.generateSphere(radius: radius)
let ballMaterial = SimpleMaterial(color: .systemOrange, roughness: 1, isMetallic: false)
let ballShape = ShapeResource.generateSphere(radius: radius)
for i in 0..<ballCount {
let ball = Entity()
let ballModel = ModelComponent(mesh: ballMesh, materials: [ballMaterial])
ball.components.set(ballModel)
let ballCollision = CollisionComponent(shapes: [ballShape])
ball.components.set(ballCollision)
var ballPhysicsBody = PhysicsBodyComponent(
material: PhysicsMaterialResource.generate(friction: 0, restitution: 0.97), /// 0.97 for near perfect elasticity
mode: .dynamic
)
ballPhysicsBody.linearDamping = 0
ballPhysicsBody.angularDamping = 0
ball.components.set(ballPhysicsBody)
let shadow = GroundingShadowComponent(castsShadow: true)
ball.components.set(shadow)
let x = startX + Float(i) * spacing
ball.position = [x, 1, 0]
anchor.addChild(ball)
}
return arView
}
func updateUIView(_ uiView: UIViewType, context: Context) {
}
}
struct PhysicsRestitutionView: View {
var body: some View {
ZStack {
ARViewPhysicsRestitution()
.ignoresSafeArea()
.background(.black)
VStack {
Spacer()
Menu {
Button("Edit", systemImage: "pencil") {}
Button("Share", systemImage: "square.and.arrow.up") {}
Button("Delete", systemImage: "trash") {}
} label: {
Text("Menu")
}
.buttonStyle(.glass)
}
.padding()
}
}
}
#Preview {
PhysicsRestitutionView()
}
RealityKit
RSS for tagSimulate and render 3D content for use in your augmented reality apps using RealityKit.
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Since updating to iOS 26.0 (and confirmed on 26.1), ARBodyTrackingConfiguration no longer detects a valid ARBodyAnchor on devices with LiDAR (e.g., iPhone 15 Pro, iPhone 17 Pro Max).
This issue reproduces in custom projects and Apple’s official sample “Capturing Body Motion in 3D”.
The AR session runs normally, but the delegate call:
func session(_ session: ARSession, didUpdate anchors: [ARAnchor])
never yields an ARBodyAnchor with valid joint transforms.
All joints return nil when calling:
body.skeleton.modelTransform(for: jointName)
resulting in 0 valid joints per frame.
Environment
• Device: iPhone 17 Pro Max (LiDAR)
• iOS: 26.0 / 26.1
• Xcode: 16.0 (stable)
• Framework: ARKit + RealityKit
• Configuration used:
config.worldAlignment = .gravityAndHeading
config.isAutoFocusEnabled = true
config.environmentTexturing = .none
session.run(config)
Also tested: with and without frameSemantics = .bodyDetection
Expected Behavior
ARBodyAnchor should be detected and body.skeleton should contain ~89 valid joints with continuous updates.
I am building a 360 photo viewer in VisionOS 26. Which allows the user to choose a 2 by 1 jpg and then renders it with a sphere mesh entity. And I use: TextureResource(contentsOf: url, options: options).
I noticed two situations here in terms of mipmaps options.
When setting "mipmapsMode: .none":
The graphic quality within the "gaze area" looks sharp and clear
The two poles (top and bottom) are perfectly rendered
Massive shimmer around the "gaze area"
When setting "mipmapsMode: .allocateAndGenerateAll":
The graphic looks slightly blurrier than in ".none" within the "gaze area"
The two poles are very blurry and hard to recognize the texture
Much less shimmer around the "gaze area"
My question would be: Is there a way to have the perfect graphic quality in ".none" without the massive shimmer?
Thank you!
Screenshots:
mipmapsMode: .none
mipmapsMode: .allocateAndGenerateAll
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
Hi, I have a hand model that is in FBX and I'm exporting it to USD in Blender. I get a skinned mesh and while I can track the whole hand how do I track each joint and assign it and animate the skinned mesh itself. All my attempts say this is not possible in RealityKit as of now. True?
Hi All,
We're a studio building an app and as part of a scene we have a 3D asset with a smoke particle emitter and a curved mesh that plays video. I notice that when the video alone is played or the particle effect alone is done then the scene works fine but the frame rate drops drastically when both are turned on.
How do I solve this because this is an important storytelling feature.
Hello,
I am in the process of implementing SharePlay support in my visionOS app. Everything runs fine when I test locally, but when my app is distributed via TestFlight, calling try await activity.activate() shows the SharePlay dialog as usual, but then when I start a new FaceTime call, my ImmersiveSpace gets dismissed.
This is only happening when the app is distributed via TestFlight, when I run it locally the ImmersiveSpace stays active as expected.
Looking at the console on my Mac I found this log:
Invalid initial client settings class: UIApplicationSceneClientSettings; expected class: MRUISharedApplicationSceneClientSettings; bundle ID: com.apple.facetime; scene ID: com.apple.facetime:SFBSystemService-DDA8C751-C0C4-487E-AD85-59EF4E6C6050
Does anyone have an idea how I can fix this? It's driving me nuts and I wasted over a day looking for a workaround but so far been unsuccessful.
Thanks!
Hello,
I've been trying to leverage instanced rendering in RealityKit on visionOS but have not had success.
RealityKit states this is supported:
https://developer.apple.com/documentation/realitykit/validating-usd-files
https://developer.apple.com/videos/play/wwdc2021/10075/?time=1373
https://developer.apple.com/videos/play/wwdc2023/10099/?time=772
RealityKit Trace metrics
Validating instancing is working:
To test I made a base visionOS app with immersive space and the entity replaced with my test usdz file. I've been using the RealityKit Trace profiling template in xcode instruments in the immersive space and volume closed. This gets consistent draw call results.
If I have a single sphere mesh with one material I get one draw call, but the number of draw calls grows linearly with mesh count no matter how my entity is configured.
What I've tried
Create a test scene in blender, export with instancing enabled
Create a test scene in Reality Composer Pro using references
Author usda files by hand based on the OpenUSD spec
Programatically create a MeshResource with Contents at runtime
References
https://openusd.org/release/api/_usd__page__scenegraph_instancing.html
https://developer.apple.com/documentation/realitykit/meshresource
https://developer.apple.com/documentation/realitykit/meshresource/instance
Thank you
Hello,
I'm getting started for my project with Xcode Cloud since I upgraded to the macOS Sequioa Beta and Xcode 16 now refuses to archive builds for TestFlight.
Somewhere very late in the build process I get the following error:
realitytool requires Metal for this operation and it is not available in this build environment
The log says this happens at:
Compile Skybox urban.skybox
My project uses RealityKit. How can I fix this issue?
Thanks!
I have a question I guess more for the Apple team.
But why are there no totally 3D experiences for the Vision Pro lineup?
I know they have given us tools to implement unity 3D games into iPhone and I guess you can also build it in RealityKit. But why at this moment are 3D games limited to just iPad and iPhone and can't you bring that into Vision Pro?
Just to explain. When I say a totally 3D game, I mean games like Gorn. I mean the Vision Pro is definitely powerful enough, but it just feels limited to tabletop games and AR games.
Is this something Apple is thinking about implementing?
Topic:
Graphics & Games
SubTopic:
RealityKit
Tags:
ARKit
Reality Composer
RealityKit
Reality Composer Pro
The issue reproducible with empty project. When you run it and tap "Open immersive space" it takes a couple of minutes to respond. The issue only reproducible on real device with debugger attached. Reproducible other developers too (not specific to my environment). Issue doesn't exists in Xcode 16.
Afer initial long delay subsequent opens works fine.
Console logs:
nw_socket_copy_info [C1:2] getsockopt TCP_INFO failed [102: Operation not supported on socket]
nw_socket_copy_info getsockopt TCP_INFO failed [102: Operation not supported on socket]
Failed to set dependencies on asset 9303749952624825765 because NetworkAssetManager does not have an asset entity for that id.
void * _Nullable NSMapGet(NSMapTable * _Nonnull, const void * _Nullable): map table argument is NULL
PSO compilation completed for driver shader copyFromBufferToTexture so=0 sbpr=256 sbpi=16384 ss=(64, 64, 1) p=70 sc=1 ds=0 dl=0 do=(0, 0, 0) in 1997
XPC connection interrupted
<<<< FigAudioSession(AV) >>>> audioSessionAVAudioSession_CopyMXSessionProperty signalled err=-19224 (kFigAudioSessionError_UnsupportedOperation) (getMXSessionProperty unsupported) at FigAudioSession_AVAudioSession.m:606
Failed to load item AXCodeItem<0x14706f250> [Rank:6000] SpringBoardUIServices [AXBundle name:/System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle/SpringBoardUIServices] [Platforms and Targets:{ iOS = SpringBoardUIServices; } Framework] [Excluded: (null)]. error: Error Domain=AXLoading Code=0 "URL does not exist: file:///System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle" UserInfo={NSLocalizedDescription=URL does not exist: file:///System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle}
Failed to load item AXCodeItem<0x14706f250> [Rank:6000] SpringBoardUIServices [AXBundle name:/System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle/SpringBoardUIServices] [Platforms and Targets:{ iOS = SpringBoardUIServices; } Framework] [Excluded: (null)]. error: Error Domain=AXLoading Code=0 "URL does not exist: file:///System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle" UserInfo={NSLocalizedDescription=URL does not exist: file:///System/Library/AccessibilityBundles/SpringBoardUIServices.axbundle}
[b30780-MRUIFeedbackTypeButtonWithBackgroundTouchDown] Playback timed out before completion (after 3111 ms)
Failed to set dependencies on asset 7089614247973236977 because NetworkAssetManager does not have an asset entity for that id.
If I trigger the apple rating modal in an Immersive space it appears on the ground in (0,0,0) I need it to be in front of the user like push notification perimssion does or other permissions requests.
I'm working on an application for viewing AMF models on macOS, using RealityKit. AMF supports several different ways to color models, including per-vertex color (where the color of a triangle is interpolated from vertex to vertex) as well as per-face color (where the color of the triangle is the same across the entire face).
I'm trying to figure out how to support those color models using a RealityKit mesh. Apple's documentation (https://developer.apple.com/documentation/realitykit/modifying-realitykit-rendering-using-custom-materials) talks about per-vertex colors, but I haven't found a way to create a mesh that includes per-vertex colors, other than use a texture map (which might be the correct solution).
Can someone give me some pointers?
Hey there, I’m currently planning to use RealityKit in a new multiplatform app I’m building. Unfortunately, I noticed that WatchOS is not supported for RealityKit, while SceneKit is getting deprecated. However, I’d like to maintain the same codebase across platforms. What are my options?
Hi team, I'm looking for the RealityKit debugger in Xcode 26 beta 3. I'm running a RealityKit app on my iPad running iPadOS 26 b3, but the debugger option is not there in Xcode.
Hello,
In my project, I have attached a ManipulationComponent to Entity A and as expected, I'm able interact with it using the built-in gestures. I have another Entity B which is a child of A that I would like to interact with as well, so I attempted to add a ManipulationComponent to B. However, no gestures seem to be registered on B; I can still interact with A but B cannot be interacted with despite having ManipulationComponents on both entities.
So I'm wondering if I'm just doing something wrong, if this is an issue with the ManipulationComponent, or if this is a limitation of the API.
Attached is the code used to add the ManipulationComponent to an Entity and it was done on both A and B:
let mc = ManipulationComponent()
model.components.set(mc)
var boxShape = ShapeResource.generateBox(width: 0.25, height: 0.05, depth: 0.25)
boxShape = boxShape.offsetBy(translation: simd_float3(0, -0.05, -0.25))
ManipulationComponent.configureEntity(model, collisionShapes: [boxShape])
if var mc = model.components[ManipulationComponent.self] {
mc.releaseBehavior = .stay
mc.dynamics.inertia = .low
model.components.set(mc)
}
I am using visionOS 26.0; let me know if there's any additional information needed.
Hi all,
I've developed some code that enables an arcball camera interaction with my scene. I've done this using components and systems. The implementation feels a bit messy as I've got gesture code on my realityView, and then a bunch of other code that uses those gesture inputs in my component and system.
Is there a demo app, or some example code that shows a nice way to encapsulate these things in to one item for custom cameras, something like Apple's .realityViewCameraControls(.orbit)
If not can anyone recommend an approach to take?
This post documents an issue I reported in feedback FB19610114 and see if anyone knows of a workaround. Here is a copy of the feedback.
Short version
Manipulation (SwiftUI OR RealityKit) fails to translate entities after changing rooms. By changing rooms, I mean a human wearing an Apple Vision Pro leaving one room and entering another room. Once this issue occurs, it impacts all apps that use these features. A device restart is the only solution I have to fix it.
Feedback FB19610114
This is an odd one. I'm using the new Manipulation Component in visionOS 26. Most of the time this works well. Sometime it stops working and when it does the only way to get it working again is to reboot the headset.
When this happens, I can continue to rotate and scale items, but translation no longer works. It is as if the item is stuck to a fixed point in the parent scene (window, volume, etc). When this bug occurs, it affects every app across the entire operating system that is using manipulation, including the RealityKit component AND the SwiftUI version. This is not limited to one app and is not limited to apps that I am working on. Once this error occurs, it affects literally any application across the operating system that is using this API, including apps from Apple.
I won't speculate on the cause of this, but I do know of one way where I can always get it to happen.
Here is how to reproduce it:
Make an Xcode project with a single entity that uses the Manipulation Component. There is no need to customize the configuration of this component. The default implementation will work.
Build and run this app on device. You can keep running from device or quit and launch the app like normal on device.
Open the app and manipulate the entity - it should work as expected.
Physically walk into another room. It is vital that you leave the current room that you are in and enter a different room entirely.
Use the digital crown to recenter your view and bring your window or volume to you.
Test the manipulation on the entity again - it should still be working as expected at this point.
Physically, move yourself and your headset into the original room where you started.
Use the digital crown to recenter your view and bring your window or volume to you.
Test the manipulation on the entity again - you should now see the issue.
When I follow the steps above, then 100% of the time manipulation translation stops working at this point. It will impact any application using this API. The only way to fix it is to restart my headset.
A few points to keep in mind
It does not matter if an app is actively being run from Xcode.
When this occurs, it impacts every single app, not just one.
When this occurs, rotation and scaling continue to work, but the entity/view cannot be translated.
This impacts BOTH the SwiftUI version and the RealityKit version.
When this occurs, the only way to "fix" it is to reboot the device.
Hello Apple team,
I'm working on an iOS AR app using SwiftUI and RealityKit,
and I was wondering if the Cinematic API can be used with a RealityKit scene. I’d like to achieve a shallow depth of field while keeping the 3D asset in focus, and vice versa.
Thanks!
When using the new RealityKit Manipulation Component on Entities, indirect input will never translate the entity - no matter what settings are applied. Direct manipulation works as expected for both translation and rotation.
Is this intended behaviour? This is different from how indirect manipulation works on Model3D. How else can we get translation from this component?
visionOS 26 Beta 2
Build from macOS 26 Beta 2 and Xcode 26 Beta 2
Attached is replicable sample code, I have tried this in other projects with the same results.
var body: some View {
RealityView { content in
// Add the initial RealityKit content
if let immersiveContentEntity = try? await Entity(named: "MovieFilmReel", in: reelRCPBundle) {
ManipulationComponent.configureEntity(immersiveContentEntity, allowedInputTypes: .all, collisionShapes: [ShapeResource.generateBox(width: 0.2, height: 0.2, depth: 0.2)])
immersiveContentEntity.position.y = 1
immersiveContentEntity.position.z = -0.5
var mc = ManipulationComponent()
mc.releaseBehavior = .stay
immersiveContentEntity.components.set(mc)
content.add(immersiveContentEntity)
}
}
}