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GCDualSenseAdaptiveTrigger API set trigger mode not working
I'm trying to add support to PS5 DualSense controller. when I try to use the API from here: https://developer.apple.com/documentation/gamecontroller/gcdualsenseadaptivetrigger?language=objc None of the API works, am I missed anything? The code is like this: if ( [ controller.extendedGamepad isKindOfClass:[ GCDualSenseGamepad class ] ] ) { GCDualSenseGamepad * dualSenseGamePad = ( GCDualSenseGamepad * )controller.extendedGamepad; auto funcSetEffectTrigger = []( TriggerEffectParams& params, GCDualSenseAdaptiveTrigger *trigger ) { if ( params.m_mode == TriggerEffectMode::Off ) { [ trigger setModeOff ]; NSLog(@"setModeOff trigger.mode:%d", trigger.mode ); } else if ( params.m_mode == TriggerEffectMode::Feedback ) { [ trigger setModeFeedbackWithStartPosition: 0.2f resistiveStrength: 0.5f ]; } else if ( params.m_mode == TriggerEffectMode::Weapon ) { [ trigger setModeWeaponWithStartPosition: 0.2f endPosition: 0.4f resistiveStrength: 0.5f ]; } else if ( params.m_mode == TriggerEffectMode::Vibration ) { [ trigger setModeVibrationWithStartPosition: position amplitude: amplitude frequency: frequency ]; } }; if ( L2 ) { funcSetEffectTrigger( params, dualSenseGamePad.leftTrigger ); } if ( R2 ) { funcSetEffectTrigger( params, dualSenseGamePad.rightTrigger ); } } I've also tested to add "Game Controllers" capability to Target, still not working. Can't find anything else from the document or forums. I've no idea what need to do.
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689
Jan ’25
RealityKit SIMD3<Float> precision decreases with distance?
The farther away the center of a large entity is, the less accurate the positioning is? For example I am changing only the y-axis position of an entity that is tens of meters long, but i notice x and z drifting slowly the farther away the center of the entity is. I would not expect the x and z to move. It might be compounding rounding errors somewhere, or maybe the RealityKit engine is deciding not to be super precise about distant objects? Otherwise I just have a bug somewhere.
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568
Mar ’25
PSVR2 controllers don't report anything in snapshot
I typically read an extended gamepad capture() and get all state. But PSVR2 controllers seem to report nothing. So the stick and other buttons don't do anything in a built app. They register as left/right controllers. This on vOS 26, Xcode 26, etc. They work correctly in the main icon view, although they don't honor inverted vertical and horiztonal scrolling. Both of the default scrolls just feel wrong. When I move left I'm want to scroll level not right. Same for up/down.
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647
Sep ’25
RealityKit and USDZ: Winding Order Issue with Negatively Scaled Meshes
Hi all, I've encountered a potential issue with how the winding order of geometry is handled when their transformations involve negative scaling. I created a simple test asset, a single triangle, to demonstrate this. The triangle's vertices are defined in a counter-clockwise ("right-handed") winding order, and its transform has a negative scale on the X-axis. According to the OpenUSD specification, this negative determinant in the transformation matrix should effectively reverse the winding order of the geometry: However, any given gprim's local-to-world transformation can flip its effective orientation, when it contains an odd number of negative scales. This condition can be reliably detected using the (Jacobian) determinant of the local-to-world transform: if the determinant is less than zero, then the gprim's orientation has been flipped, and therefore one must apply the opposite handedness rule when computing its surface normals (or just flip the computed normals) for the purposes of hidden surface detection and lighting calculations. When I view the asset in tools like Blender or Preview on macOS, it behaves as expected. The triangle's effective orientation is flipped to CW. However, when the same asset is viewed in Reality Composer Pro or with QuickLook on iOS, its effective orientation remains CCW. In other words, the triangle faces the opposite direction. My questions for the community and Apple are: Is this behavior in RealityKit a known issue? If this is a known issue, is there official guidance for DCC tools on how to export USDZ assets to ensure they appear correctly in the Apple ecosystem? Any insights or recommendations would be greatly appreciated.
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How to use MTKTextureLoader to load png data
I am trying to load some PNG data with MTKTextureLoader newTextureWithData,but the result shows wrong at the alpha area. Here is the code. I have an image URL, after it downloads successfully, I try to use the data or UIImagePNGRepresentation (image), they all show wrong. UIImage *tempImg = [UIImage imageWithData:data]; CGImageRef cgRef = tempImg.CGImage; MTKTextureLoader *loader = [[MTKTextureLoader alloc] initWithDevice:device]; id<MTLTexture> temp1 = [loader newTextureWithData:data options:@{MTKTextureLoaderOptionSRGB: @(NO), MTKTextureLoaderOptionTextureUsage: @(MTLTextureUsageShaderRead), MTKTextureLoaderOptionTextureCPUCacheMode: @(MTLCPUCacheModeWriteCombined)} error:nil]; NSData *tempData = UIImagePNGRepresentation(tempImg); id<MTLTexture> temp2 = [loader newTextureWithData:tempData options:@{MTKTextureLoaderOptionSRGB: @(NO), MTKTextureLoaderOptionTextureUsage: @(MTLTextureUsageShaderRead), MTKTextureLoaderOptionTextureCPUCacheMode: @(MTLCPUCacheModeWriteCombined)} error:nil]; id<MTLTexture> temp3 = [loader newTextureWithCGImage:cgRef options:@{MTKTextureLoaderOptionSRGB: @(NO), MTKTextureLoaderOptionTextureUsage: @(MTLTextureUsageShaderRead), MTKTextureLoaderOptionTextureCPUCacheMode: @(MTLCPUCacheModeWriteCombined)} error:nil]; }] resume];
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624
May ’25
Tile Shaders performance when writing to tile texture vs. resolve texture
I am working on a custom resolve tile shader for a client. I see a big difference in performance depending on where we write to: 1- the resolve texture of the color attachment 2- a rw tile shader texture set via [renderEncoder setTileTexture: myResolvedTexture] Option 2 is more than twice as slow than option 1. Our compute shader writes to 4 UAVs so just using the resolve texture entry is not possible. Why such a difference as there is no more data being written? Can option 2 be as fast as option 1? I can demonstrate the issue in a modified version of the Multisample code sample.
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568
Feb ’25
Roblox freezing on MacOS 26.1 Beta
After updating to MacOS 26.1 I encountered an issue that Roblox tends to freeze quite often for 10 - 60 seconds at most, this is really annoying that it is doing this as i play the game a lot. My theory is that it is like a driver issue with metal or something, I have reinstalled MacOS, reinstalled the game and lowed the performance manually but nothing is working. Wondering if you could help, when it will be fixed and if others are having the same issue. Many thanks, William.
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730
Oct ’25
Feature Request: Support .reality File Export in Reality Composer Pro for Mac
I am an AR developer working on Apple Silicon Macs. Currently, Reality Composer Pro does not allow exporting .reality files, and Reality Composer (classic) is not available for Apple Silicon. This creates a gap in the workflow for ARKit/RealityKit developers who need interactive .reality files for use in Xcode projects. Having the ability to export .reality files directly from Reality Composer Pro on Mac would greatly streamline development and enable a fully native workflow on modern Macs. Alternatively, bringing Reality Composer (classic) to Apple Silicon would also resolve this issue. I have submitted this as a feature request via Feedback Assistant (FB17900386). I encourage others with similar needs to reply or submit feedback as well. Thank you!
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187
Jul ’25
Sample code for WWDC25 Session
Hi! I watched the WWDC25 session "Bring your SceneKit project to RealityKit" which seemed like a great resource for those of us transitioning from the now-deprecated SceneKit framework. The session mentioned that the full sample code for the project would be available to download, but I haven't been able to find it in the Code section of the video page or in the Sample Code Library. Has the sample code been released yet? Having the project code would make it much easier to follow along with the RealityKit changes shown in the video. Thanks again for the great session.
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276
Jun ’25
X11 applications run with XQuartz not working properly in macOS Tahoe
Hello XQuartz is an open-source effort to develop a version of the X.Org X Window System (https://www.xquartz.org/), widely used to bring graphical support to applications running in remote servers (usually via SSH). Since macOS Tahoe, XQuartz fails to refresh properly on window resize (more info here https://github.com/XQuartz/XQuartz/issues/438#issuecomment-3371409500), leading to severe usability issues. The XQuartz developers are already aware of the issue, but I’m wondering if there’s anything we can do at the OS level to resolve it and restore the usual behavior from before macOS Tahoe. Thanks, KiM
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Transferring Apps with iCloud KVS
Hi All! I'm being asked to migrate an app which utilizes iCloud KVS (Key Value Storage). This ability is a new-ish feature, and the documentation about this is sparse [1]. Honestly, the entire documentation about the new iCloud transfer functionality seems to be missing. Same with Game Center / GameKit. While the docs say that it should work, I'd like to understand the process in more detail. Has anyone migrated an iCloud KVS app? What happens after the transfer goes through, but before the first release? Do I need to do anything special? I see that the Entitlements file has the TeamID in the Key Value store - is that fine? <key>com.apple.developer.ubiquity-kvstore-identifier</key> <string>$(TeamIdentifierPrefix)$(CFBundleIdentifier)</string> Can someone please share their experience? Thank you! [1] https://developer.apple.com/help/app-store-connect/transfer-an-app/overview-of-app-transfer
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2.2k
Feb ’25
Are there complete code examples available for “Combine Metal 4 machine learning and graphics”?
Hello, I recently watched the WWDC2025 session titled “Combine Metal 4 machine learning and graphics” (https://developer.apple.com/videos/play/wwdc2025/262/ ), and I’m very excited about the new Metal 4 features that integrate machine learning with graphics—such as neural ambient occlusion, shader-based ML inference, and the use of MTLTensor and MTL4MachineLearningCommandEncoder. While the session includes helpful code snippets and a compelling debug demo (e.g., the neural ambient occlusion example), the implementation details are not fully shown, and I haven’t been able to find a complete, runnable sample project that demonstrates end-to-end integration of ML and rendering in Metal 4. Would Apple be able to provide a full, working example—such as an Xcode project—that shows how to: Export a model to an .mlpackage, Convert it to an .mtlpackage, Use MTL4MachineLearningCommandEncoder alongside render passes, Or embed small neural networks directly in shaders using Shader ML? Having such a sample would greatly help developers like me adopt these powerful new capabilities correctly and efficiently. Thank you very much for your time and support! Best regards,
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857
Nov ’25
visionOS + Unity PolySpatial: Is 15,970 MeshFilters the True Upper Limit for Industrial Scenes?
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)
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646
Oct ’25
GKMatch.chooseBestHostingPlayer(_:) always returns nil player
I'm building a game with a client-server architecture. Using GKMatch.chooseBestHostingPlayer(_:) rarely works. When I started testing it today, it worked once at the very beginning, and since then it always succeeds on one client and returns nil on the other client. I'm testing with a Mac and an iPhone. Sometimes it fails on the Mac, sometimes on the iPhone. On the device that it succeeds on, the provided host can be the device itself or the other one. I created FB9583628 in August 2021, but after the Feedback Assistant team replied that they are not able to reproduce it, the feedback never went forward. import SceneKit import GameKit #if os(macOS) typealias ViewController = NSViewController #else typealias ViewController = UIViewController #endif class GameViewController: ViewController, GKMatchmakerViewControllerDelegate, GKMatchDelegate { var match: GKMatch? var matchStarted = false override func viewDidLoad() { super.viewDidLoad() GKLocalPlayer.local.authenticateHandler = authenticate } private func authenticate(_ viewController: ViewController?, _ error: Error?) { #if os(macOS) if let viewController = viewController { presentAsSheet(viewController) } else if let error = error { print(error) } else { print("authenticated as \(GKLocalPlayer.local.gamePlayerID)") let viewController = GKMatchmakerViewController(matchRequest: defaultMatchRequest())! viewController.matchmakerDelegate = self GKDialogController.shared().present(viewController) } #else if let viewController = viewController { present(viewController, animated: true) } else if let error = error { print(error) } else { print("authenticated as \(GKLocalPlayer.local.gamePlayerID)") let viewController = GKMatchmakerViewController(matchRequest: defaultMatchRequest())! viewController.matchmakerDelegate = self present(viewController, animated: true) } #endif } private func defaultMatchRequest() -> GKMatchRequest { let request = GKMatchRequest() request.minPlayers = 2 request.maxPlayers = 2 request.defaultNumberOfPlayers = 2 request.inviteMessage = "Ciao!" return request } func matchmakerViewControllerWasCancelled(_ viewController: GKMatchmakerViewController) { print("cancelled") } func matchmakerViewController(_ viewController: GKMatchmakerViewController, didFailWithError error: Error) { print(error) } func matchmakerViewController(_ viewController: GKMatchmakerViewController, didFind match: GKMatch) { self.match = match match.delegate = self startMatch() } func match(_ match: GKMatch, player: GKPlayer, didChange state: GKPlayerConnectionState) { print("\(player.gamePlayerID) changed state to \(String(describing: state))") startMatch() } func startMatch() { let match = match! if matchStarted || match.expectedPlayerCount > 0 { return } print("starting match with local player \(GKLocalPlayer.local.gamePlayerID) and remote players \(match.players.map({ $0.gamePlayerID }))") match.chooseBestHostingPlayer { host in print("host is \(String(describing: host?.gamePlayerID))") } } }
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349
Apr ’25
USDZ files with camera can't be opened on IOS 18.2/iPadOS 18.2 correctly.
Hi experts, When I open a USDZ file which contains perspective cameras by "Files" app in IOS 18.2/iPadOS 18.2, I can't see anything. And when I open the USDZ file in IOS 18.1/iPadOS 18.1, it works well. On the other hand, when I open a USDZ file which contains orthographic cameras in IOS 18.1 or IOS 18.2, the scene is stuck. Could you help to solve these issues please? Thanks.
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653
Dec ’24
GKLocalPlayer save and fetch data to iCloud issue
Hi all I have two mystic issues with saving and fetching data to and from iCloud. Both repro only after first launch of an app. 1. [GKLocalPlayer fetchSavedGamesWithCompletionHandler:] After first attempt I can see 0 saved games (but i know that there is at least one saved game) and there is no any error. In case if I try fetch one more time (without any additional actions) even immediately after first attempt I receive saved games correctly (not 0) 2. [GKLocalPlayer saveGameData: withName: completionHandler:] After first attempt I can see error The requested operation could not be completed because local player has not been authenticated. In case if I try save one more time (without any additional actions) even immediately after first attempt I can save data successfully without any error I found the same issue in StackOverflow, but there are no fixes...
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1.4k
Feb ’25
Scene with over 12,000 duplicate entities
I am creating a RealityKit scene that will contain over 12,000 duplicate cubes arranged in a circle (see image below). This is for some high-energy physical simulations I am doing. I accomplish this scene by creating a single cube and cloning it a bunch of times. So, I there is a single MeshResource and Material even though there are a lot of entities. I have confirmed this by checking with Swift's === operator. Even with this, the program is unworkably slow. Any suggestions or tricks that could help with this type of scene? Using a single geometry was the trick to getting SceneKit to work fast with geometries like this. I've been updating my software to RealityKit because I far prefer the structure of RealityKit over SceneKit.
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1.4k
Jan ’25
RealityKit Instanced Rendering on visionOS
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
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1.4k
Oct ’25