I have a model that uses a video material as the surface shader and I need to also use a geometry modifier on the material.
This seemed like it would be promising (adapted from https://developer.apple.com/wwdc21/10075 ~5m 50s).
// Did the setup for the video and AVPlayer eventually leading me to
let videoMaterial = VideoMaterial(avPlayer: avPlayer)
// Assign the material to the entity
entity.model!.materials = [videoMaterial]
// The part shown in WWDC: Set up the library and geometry modifier before, so now try to map the new custom material to the video material
entity.model!.materials = entity.model!.materials.map { baseMaterial in
try! CustomMaterial(from: baseMaterial, geometryModifier: geometryModifier)
}
But, I get the following error
Thread 1: Fatal error: 'try!' expression unexpectedly raised an error: RealityFoundation.CustomMaterialError.defaultSurfaceShaderForMaterialNotFound
How can I apply a geometry modifier to a VideoMaterial? Or, if I can't do that, is there an easy way to route the AVPlayer video data into the baseColor of CustomMaterial?
RealityKit
RSS for tagSimulate and render 3D content for use in your augmented reality apps using RealityKit.
Posts under RealityKit tag
200 Posts
Selecting any option will automatically load the page
Post
Replies
Boosts
Views
Activity
I'm trying to understand how Apple handles dragging windows around in an immersive space. 3d Gestures seem to be only half of the solution in that they are great if you're standing still and want to move the window an exaggerated amount around the environment, but if you then start walking while dragging, the amplified gesture sends the entity flying off into the distance. It seems they quickly transition from one coordinate system to another depending on if the user is physically moving. If you drag a window and start walking the movement suddenly matches your speed. When you stop moving, you can push and pull the windows around again like a super hero. Am I missing something obvious in how to copy this behavior? Hello world, which uses the 3d gesture has the same problem. You can move the world around but if you walk with it, it flies off. Are they tracking the head movement and if it's moved more than a certain amount it uses that offset instead? Is there anything out of the box that can do this before I try and hack my own solution?
I have tried every combination of suggestions to get a skybox to appear. Using swiftUI, realityKit and iOS. Non immersive environment. Does anyone have code that works to display a skybox.
When i use a do/catch loop i get environmentResource not found. I have checked the syntax, ensured the folder is referencing the target, used the same name for the folder as the file, the file is a .hdr (i assume this is supported), i have moved the file folder to the top level - no change.
I'm preparing my submission for the Swift Student Challenge, and I have a couple of questions regarding the development environment.
Is it allowed to use Xcode to program my scene, or do I have to use Swift Playgrounds?
Can I use iPadOS 18 for development? I noticed that Swift Playgrounds currently only supports up to iPadOS 17.5, but I would like to use RealityView, which is only available starting from iPadOS 18.
I appreciate any clarification on this. Thanks in advance!
Topic:
Community
SubTopic:
Swift Student Challenge
Tags:
Swift Student Challenge
Swift Playground
Playground Support
RealityKit
A ShaderGraphMaterial with an Occlusion Surface Output generated with RealityComposer 2 fails to load on iOS 18 and macOS 15 with the following error:
RealityFoundation.ShaderGraphMaterial.LoadError.invalidTypeFound (https://developer.apple.com/documentation/realitykit/shadergraphmaterial/loaderror/invalidtypefound)
This happens with both https://developer.apple.com/documentation/shadergraph/realitykit/occlusion-surface-(realitykit) and https://developer.apple.com/documentation/shadergraph/realitykit/shadow-receiving-occlusion-surface-(realitykit)
RealityView { content in
do {
let bgEntity = ModelEntity(mesh: .generateCone(height: 0.5, radius: 0.1), materials: [SimpleMaterial(color: .red, isMetallic: true)])
bgEntity.position.z = -0.2
content.add(bgEntity)
let occlusionMaterial = try await ShaderGraphMaterial(named: "/Root/OcclusionMaterial", from: "OcclusionMaterial")
let testEntity = ModelEntity(mesh: .generateSphere(radius: 0.4), materials: [occlusionMaterial])
content.add(testEntity)
content.cameraTarget = testEntity
} catch {
print("Shader Graph Load Error:")
dump(error)
}
}
.realityViewCameraControls(.orbit)
.edgesIgnoringSafeArea(.all)
Feedback ID: FB15081296
Topic:
Spatial Computing
SubTopic:
Reality Composer Pro
Tags:
RealityKit
Reality Composer Pro
Shader Graph Editor
I'm developing a VisionOS app with bouncing ball physics and struggling to achieve natural bouncing behavior using RealityKit's physics system. Despite following Apple's recommended parameters, the ball loses significant energy on each bounce and doesn't behave like a real basketball, tennis ball, or football would.
With identical physics parameters (restitution = 1.0), RealityKit shows significant energy loss. I've had to implement a custom physics system to compensate, but I want to use native RealityKit physics. It's impossible to make it work by applying custom impulses.
Ball Physics Setup (Following Apple Forum Recommendations)
// From PhysicsManager.swift
private func createBallEntityRealityKit() -> Entity {
let ballRadius: Float = 0.05
let ballEntity = Entity()
ballEntity.name = "bouncingBall"
// Mesh and material
let mesh = MeshResource.generateSphere(radius: ballRadius)
var material = PhysicallyBasedMaterial()
material.baseColor = .init(tint: .cyan)
material.roughness = .float(0.3)
material.metallic = .float(0.8)
ballEntity.components.set(ModelComponent(mesh: mesh, materials: [material]))
// Physics setup from Apple Developer Forums
let physics = PhysicsBodyComponent(
massProperties: .init(mass: 0.624), // Seems too heavy for 5cm ball
material: PhysicsMaterialResource.generate(
staticFriction: 0.8,
dynamicFriction: 0.6,
restitution: 1.0 // Perfect elasticity, yet still loses energy
),
mode: .dynamic
)
ballEntity.components.set(physics)
ballEntity.components.set(PhysicsMotionComponent())
// Collision setup
let collisionShape = ShapeResource.generateSphere(radius: ballRadius)
ballEntity.components.set(CollisionComponent(shapes: [collisionShape]))
return ballEntity
}
Ground Plane Physics
// From GroundPlaneView.swift
let groundPhysics = PhysicsBodyComponent(
massProperties: .init(mass: 1000),
material: PhysicsMaterialResource.generate(
staticFriction: 0.7,
dynamicFriction: 0.6,
restitution: 1.0 // Perfect bounce
),
mode: .static
)
entity.components.set(groundPhysics)
Wall Physics
// From WalledBoxManager.swift
let wallPhysics = PhysicsBodyComponent(
massProperties: .init(mass: 1000),
material: PhysicsMaterialResource.generate(
staticFriction: 0.7,
dynamicFriction: 0.6,
restitution: 0.85 // Slightly less than ground
),
mode: .static
)
wall.components.set(wallPhysics)
Collision Detection
// From GroundPlaneView.swift
content.subscribe(to: CollisionEvents.Began.self) { event in
guard physicsMode == .realityKit else { return }
let currentTime = Date().timeIntervalSince1970
guard currentTime - lastCollisionTime > 0.1 else { return }
if event.entityA.name == "bouncingBall" || event.entityB.name == "bouncingBall" {
let normal = event.collision.normal
// Distinguish between wall and ground collisions
if abs(normal.y) < 0.3 { // Wall bounce
print("Wall collision detected")
} else if normal.y > 0.7 { // Ground bounce
print("Ground collision detected")
}
lastCollisionTime = currentTime
}
}
Issues Observed
Energy Loss: Despite restitution = 1.0 (perfect elasticity), the ball loses ~20-30% energy per bounce
Wall Sliding: Ball tends to slide down walls instead of bouncing naturally
No Damping Control: Comments mention damping values but they don't seem to affect the physics
Change in mass also doesn't do much.
Custom Physics System (Workaround)
I've implemented a custom physics system that manually calculates velocities and applies more realistic restitution values:
// From BouncingBallComponent.swift
struct BouncingBallComponent: Component {
var velocity: SIMD3<Float> = .zero
var angularVelocity: SIMD3<Float> = .zero
var bounceState: BounceState = .idle
var lastBounceTime: TimeInterval = 0
var bounceCount: Int = 0
var peakHeight: Float = 0
var totalFallDistance: Float = 0
enum BounceState {
case idle
case falling
case justBounced
case bouncing
case settled
}
}
Is this energy loss expected behavior in RealityKit, even with perfect restitution (1.0)?
Are there additional physics parameters (damping, solver iterations, etc.) that could improve bounce behavior?
Would switching to Unity be necessary for more realistic ball physics, or am I missing something in RealityKit?
Even in the last video here: https://stepinto.vision/example-code/collisions-physics-physics-material/ bounce of the ball is very unnatural - stops after 3-4 bounces. I apply custom impulses, but then if I have walls around the ball, it's almost impossible to make it look natural. I also saw this post https://developer.apple.com/forums/thread/759422 and ball is still not bouncing naturally.
Hi team,
I believe I’ve found a registration issue between ARFrame.sceneDepth and ARFrame.capturedImage when using high-resolution frame capture on a 2022 iPad Pro (6th gen).
When enabling high-resolution capture:
if let highResFormat = ARWorldTrackingConfiguration.recommendedVideoFormatForHighResolutionFrameCapturing {
config.videoFormat = highResFormat
}
…
arView.session.captureHighResolutionFrame { ... }
the depth map provided by ARFrame.sceneDepth no longer aligns correctly with the corresponding high-resolution capturedImage.
This misalignment results in consistently over-estimated distance measurements in my app (which relies on mapping depth to 2D pixel coordinates).
iPad Pro (6th gen): misalignment occurs only when capturing high-resolution frames.
iPhone 16 Pro: depth is correctly registered for both standard and high-resolution captures.
It appears the camera intrinsics, specifically the FOV, change between the “regular” resolution stream and the high-resolution capture on the iPad. My suspicion is that the depth data continues using the intrinsics of the lower resolution stream, resulting in an unregistered depth-to-RGB mapping.
Once I have the iPad in hand again, I will confirm whether camera.intrinsics or FOV differ between the low-res and high-res frames.
Is this a known issue with high-resolution frame capture on the 2022 iPad Pro? If not, I’m happy to provide some more thorough sample code.
Thanks for your time!
Hi everyone! I am working on AR app and wanted to implement object occlusion because it removes drift pretty much from the object. This working great with RealityKit sample But I am unable to replicate such behaviour it with scenekit. Because scenekit does not offer object occlusion. Can we say scenekit is getting depricated, and we should re-write app in RealityKit (which is obviously a big task)?
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?
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!
Is there any support pr plans for support for for raytraced reflections in RealityKit on the Vision Pro M5? I cannot find any documentation regarding this topic.
Hello,
Question re: iOS RealityView postProcess. I've got a working postProcess kernel and I'd like to add some depth-based effects to it. Theoretically I should be able to just do:
encoder.setTexture(context.sourceDepthTexture, index: 1)
and then in the kernel:
texture2d<float, access::read> depthIn [[texture(1)]]
...
outTexture.write(depthIn.read(gid), gid);
And I consistently see all black rendered to the view. The postProcess shader works, so that's not the issue. It just seems to not be receiving actual depth information.
(If I set a breakpoint at the encoder setTexture step, I can see preview the color texture of the scene, but the context's depthTexture looks like all NaN / blank.)
I've looked at all the WWDC samples, but they include ARView for all the depth sample code, which has a different set of configuration options than RealityView. So far I haven't seen anywhere to explicitly tell RealityView "include the depth information". So I'm not sure if I'm missing something there.
It appears that there is indeed a depth texture being passed, but it looks blank.
Is there a working example somewhere that we can reference?
Game Controller Input Limitations in visionOS Volumetric Windows
Hello Apple Developer Community,
I'm developing a game for visionOS and have encountered significant limitations with game controller input when using volumetric windows (WindowGroup with .volumetric style). I'd appreciate clarification on whether this is expected behavior and any guidance on best practices.
🧩 Issue Summary
When using a DualSense controller with a volumetric window in visionOS, only a subset of controller inputs are available to the app. The remaining inputs appear to be reserved by the system for UI navigation.
✅ Working Inputs (Volumetric Window)
D-Pad (all directions)
L3 (left thumbstick button click)
R3 (right thumbstick button click)
Menu button
Options button
❌ Not Working Inputs (Volumetric Window)
Left thumbstick analog movement (used for UI scrolling instead)
Right thumbstick analog movement (used for UI scrolling instead)
Face buttons (Cross, Circle, Square, Triangle / A, B, X, Y)
Shoulder buttons (L1, R1)
Triggers (L2, R2)
Key observation: When moving the left thumbstick in a volumetric window, the window's UI scrolls vertically instead of sending input to my app's GameController handlers. Similarly, face buttons seem to be reserved for system UI interactions.
⚙️ Implementation Details
I'm using the standard GameController framework:
Connect to controller via GCController.controllers()
Access extendedGamepad profile
Set up valueChangedHandler and pressedChangedHandler for all inputs
Handlers confirmed registered via logging
Working inputs (D-Pad, L3, R3) trigger immediately and consistently
Non-working inputs (thumbsticks, face buttons) never trigger
🧠 Critical Finding: ImmersiveSpace Works Perfectly
When testing the exact same code in an ImmersiveSpace (.mixed immersion style), all controller inputs work perfectly:
✅ Both thumbsticks provide full analog input
✅ All face buttons trigger their handlers
✅ All shoulder buttons and triggers work correctly
✅ 100% success rate with no intermittent issues
This suggests the issue isn't with my code, but rather how visionOS handles controller input differently between Volumetric Windows and ImmersiveSpace.
🧪 Test Environment
I created a minimal test project (Controller-Playground) to isolate the issue:
A simple ControllerTester class that registers all GameController handlers
A visual UI showing real-time input state
No game logic, RealityKit physics, or other complexity
Results
In volumetric window: Only D-Pad, L3, R3, Menu, Options work
In ImmersiveSpace: All inputs work perfectly
This confirms the limitation exists at the visionOS platform level, not in app code.
🧰 Attempted Workarounds
I tried the following without success:
Setting GCSupportsControllerUserInteraction = false in Info.plist
Setting UIRequiresFullScreen = true
Changing window styles (.plain, .volumetric)
Polling vs. handler-based input approaches
Various threading models (MainActor, separate thread)
Result: The only way to enable full controller support is to switch to ImmersiveSpace.
❓ Questions for Apple
Is this input reservation behavior in volumetric windows intended and documented?
Are game controllers expected to have limited functionality in volumetric windows while full functionality is reserved for ImmersiveSpace?
Is there a way to request full controller input access in a volumetric window, or is ImmersiveSpace the only option for complete controller support?
Where can I find official documentation about controller input differences between window types?
Are there any APIs or configuration options to disable system controller shortcuts in volumetric windows?
🎯 Impact
This limitation has a significant effect on game design and architecture:
Volumetric windows offer a multitasking-friendly, less immersive experience
ImmersiveSpace provides full controller support but may be more immersive than some games require
Games that only need basic D-Pad and button input can work fine in volumetric windows
Games requiring analog sticks or face buttons must currently use ImmersiveSpace
It would be very helpful if Apple could clarify or reference existing documentation regarding controller input handling in different visionOS window types. If such documentation doesn't exist yet, it might be valuable to include this information in future developer guides or best-practice documents.
🕹 Current Workaround
For now, I'm using:
D-Pad for character movement (digital 8-direction)
R3 (right stick click) as a substitute for the "X" button
This setup allows the game to function within a volumetric window, though full controller support still requires ImmersiveSpace.
📄 Request
If this is expected behavior, I may have simply missed the relevant documentation — could you please point me to any existing resources that explain this design?
If there isn't one yet, it would be great if future visionOS documentation could:
Clearly outline controller input behavior across window types
Provide guidance on when to use Volumetric Windows vs. ImmersiveSpace for games
Consider adding an API option to request full controller access when appropriate
If this is not expected behavior, I'm happy to file a detailed bug report with sample code.
💻 System Information
visionOS: Latest Simulator
Xcode: Latest version
Controller: Sony DualSense
Framework: GameController (standard extendedGamepad profile)
Test project: Minimal reproducible example available
Thank you for any clarification or guidance you can provide. This information would be valuable for many developers working on visionOS games.
When assigning a ManipulationComponent to an Entity SceneEvents.WillRemoveEntity will be called for that Entity.
Expected Behavior: the Entity is not (even if temporarily) removed from the Scene and no SceneEvents will be triggered as a result of assigning a ManipulationComponent.
FB20872220
I want to let users place 2D/3D “artworks” on detected walls and have them reappear in exactly the same real‑world spot after quitting and relaunching the app (like widgets do, but for my own entities).Environment: Xcode 26, visionOS 2.0, RealityKit + ARKitSession/WorldTrackingProvider Entities are parented to a holder that’s aligned to a wall via plane/mesh raycasts.
What I’ve tried:
Create a WorldAnchor at placement, save UUID + full 4×4 transform On next launch, re-create the WorldAnchor (or set the saved transform) and attach the entity Gate restore on relocalization/mesh updates and disable all raycast/search after restore Issue: After relaunch, placement still resolves relative to current device pose, not the same wall position.
Questions:
Is there a public API in visionOS 2.0 to persist app‑managed world anchors across sessions (room‑fixed), e.g., AnchorStore or equivalent?
If not, what’s the recommended pattern to reliably restore wall‑anchored content?
Are persistence features mentioned for widgets/windows available to third‑party RealityKit entities?
Can the event of long pressing the digital display in VisionPro be monitored in RealityView
I used colorpick on the view, but after converting it to a model, colorpick doesn't work. Is there any way to use colorpick
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()
}
Breaking Through PolySpatial's ~8k Object Limit – Seeking Alternative Approaches for Large-Scale Digital Twins
Confirmed: PolySpatial make Doubles MeshFilter Count – Hard Limit at ~8k Active Objects (15.9k Total)
Project Context & Research Goals
I’m developing an industrial digital twin application for Apple Vision Pro using Unity’s PolySpatial framework (RealityKit rendering in Unbounded_Volume mode). The scene contains complex factory environments with:
Production line equipment Many fragmented grid objects need to be merged.)
Dynamic product racks (state-switchable assets)
Animated worker avatars
To optimize performance, I’m systematically testing visionOS’s rendering capacity limits. Through controlled stress tests, I’ve identified a critical threshold:
Key Finding
When the total MeshFilter count reaches 15,970 (system baseline + 7,985 user-created objects × 2 due to PolySpatial cloning), the application crashes consistently. This suggests:
PolySpatial’s mirroring mechanism effectively doubles GameObject overhead
An apparent hard limit exists around ~8k active mesh objects in practice
Objectives for This Discussion
Verify if others have encountered similar limits with PolySpatial/RealityKit
Understand whether this is a:
Memory constraint (per-app allocation)
Render pipeline limit (Metal draw calls)
Unity-specific PolySpatial behavior
Explore optimization strategies beyond brute-force object reduction
Why This Matters
Industrial metaverse applications require rendering thousands of interactive objects . Confirming these limits will help our team:
Design safer content guidelines
Prioritize GPU instancing/LOD investments
Potentially contribute back to PolySpatial’s optimization
I’d appreciate insights from engineers who’ve:
Pushed similar large-scale scenes in visionOS
Worked around PolySpatial’s cloning overhead
Discovered alternative capacity limits (vertices/draw calls)
I'm currently implementing 180° / 360° immersive video for my app.
I easily implemented 360° by just applying VideoMaterial to flipped sphere.
But I'm stuck at 180°. I'm trying to implement by applying VideoMaterial to hemisphere (half sphere). I want to make VideoMaterial to be visible half front sphere and half back sphere transparent / clear.
Would there be any advice / information / idea to implement this? Your help would be grateful.