Hello, I’m working on an iOS app built around a single skinned character with fur, rendered in Metal and shown in close-up, so it takes up most of the screen. It needs to run at a steady 60fps, and the oldest hardware I want to support is the A15 (iPhone 13). The fur will be alpha cards layered over the base mesh. All of the character’s motion is computed on the GPU each frame, and ARKit and Vision hand tracking are running at the same time. This is what I have so far. A 180k-triangle test character with no hair cards runs smoothly in the Simulator on my Mac (yes, I know it's not entirely representative of the GPU numbers on a phone). On an actual iPhone 16, a synthetic bench (60k vertices, 4 influences each) put GPU skinning at 1.1 to 1.3 ms whether I used 250 joints or 1000, so I’m not worried about skinning. The final model is still being built, so I can’t test the real thing yet, but I have to give the modeler a budget now. I’m thinking of 100k to 120k triangles in total, base mesh plus alpha cards. Would that look fairly reasonable for an A15, or not? Thanks!

Hey all, hoping someone on the Metal team can take a look at this one. It's a crash inside Metal 4's binary capture, and as far as I can tell there's no way to fix it from the app side. Filed as FB25478288 (partial repro is link is there too). Why I think it matters The setup that crashes is basically the recommended Metal 4 workflow: one MTL4Compiler with a MTL4PipelineDataSetSerializer (CaptureBinaries) attached, called from maximumConcurrentCompilationTaskCount threads, to harvest pipelines for an offline archive. Lots of pipelines share a vertex function, which I'd guess is true for most real renderers. The crash is 100% inside Metal.framework, with no app code on the crashing thread. It's easy to hit: 3 out of 3 harvest runs crashed for us, one of them 2 s in. The serializer is attached to the compiler implicitly, so the app can't put a lock around whatever it does internally. MTL4Compiler is Sendable, and the docs say it handles multithreading by default, so I'd expect capture to be thread-safe too. Environment MacBook Pro M2 Max, macOS 27.2, Xcode 27.2, Metal toolchain 32023.922.4 Also reported on an M3 Pro ~33k render pipelines over ~16k vertex functions, up to ~1,000 pipelines in a row sharing one vertex function MTL4RenderPipelineDescriptor with MTL4LibraryFunctionDescriptor stages (sometimes wrapped in MTL4SpecializedFunctionDescriptor), all colour attachments Unspecialized The serializer gets written out with serializeAsArchiveAndFlushToURL: every so often, then we start a fresh compiler + serializer Crash EXC_BAD_ACCESS (SIGSEGV), "possible pointer authentication failure": objc_msgSend MultiLevelAirntBinaryCache::getElementAtDestination(MTLBinaryKey*, ...) -[MTLCompiler compileFunctionRequestInternal:frameworkLinking:linkDataSize:reflectionOnly:compilerTask:completionHandler:] ... AGX::Compiler::compileProgram<AGX::VertexProgramKey, ...>It looks like a use-after-free: two compiles capturing the same vertex program at the same time, and an entry in the destination archive gets freed while the other one is still using it. It only happens with capture on, and it goes away if we never let two capture compiles that share a stage function run at once. Workaround we ship (not great) A lock per stage function around each capture compile, plus sending runs of pipelines that share a vertex shader to the same thread. That stopped the crashes, but we had to put a timeout on the lock, because the compiler occasionally never returns, so in theory it can still race. Second, related crash If serializeAsArchiveAndFlushToURL: runs while other threads are still compiling into that serializer, we get a different crash (null deref at 0x30) in dispatch_data_create_map ← -[_MTLBinaryArchive newArchiverIdWithBinaryKey:entry:srcArchiverId:functionType:]. Our standalone repro hits this one reliably. The getElementAtDestination crash only shows up with our real workload so far. Repro + details https://github.com/Aeonitis/metal4-capture-race It's a small Objective-C repro (Metal + Foundation only) with a bunch of modes, the results so far, and a comparison with how Vulkan (VkPipelineCache) and D3D12 spell out the thread-safety rules for this same pattern. Questions Is capturing from multiple threads into one MTL4PipelineDataSetSerializer meant to be supported? If not, could the docs say so? Is one compiler + one serializer per thread a safe workaround, or is there shared state between compilers in the same process that would still race? Is calling serializeAsArchiveAndFlushToURL: while compiles are still in flight on that serializer allowed? Is this already fixed in a seed

I ma trying to figure out if there is a Boolean subtraction functionality native in SceneKit or RealityKit. Simple operation like cutting a hole in a box from a sphere. If not, are there any libraries (free) that I can look into?

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?

I have 2 planes with textures on. I want these planes to intersect [ –|– ], and I want the blend mode to be additive. Currently I get z fighting on the planes, and I can't see how to set blend modes. I've done this before in Unity and Godot in a fairly straight forward manner. How do I accomplish this with RealityKit, preferably using code only (my scene is quite dynamic)? Do I need to do it with a shader manually? How can I stop the z fighting?

Is there any limitation in Vision Pro when loading scenes with large-scale models? ​Test Case: Asset: Composite USDA file containing ​10 individual models​ (total triangles count: ~4.2M) Simulator: Loads and renders correctly Real Device: Loads asset successfully but ​ failure during rendering phase: Environment abruptly dims System spontaneously reboots How can we resolve this issue? Below are excerpted logs preceding the crash: <<<< FigAudioSession(AV) >>>> audioSessionAVAudioSession_CopyMXSessionProperty signalled err=-19224 (kFigAudioSessionError_UnsupportedOperation) (getMXSessionProperty unsupported) at FigAudioSession_AVAudioSession.m:606 Attempted to add ornament: <MRUIPlatterOrnament: 0x10a658f00; _isInternal: YES; _displaceWindowChrome: NO; _canCaptureUI: NO; _isBeingRemoved: NO; contentAnchorPoint3D: "{0.5, 0.5, 0}"; position: <MRUIPlatterOrnamentRelativePosition: 0x105b68e70; anchorPoint: {0.5, 0.5, 1}>; rotation: "{{0, 0, 0}, 0}"; opacity: 1.000000; canFollowUser: YES; effectiveOffset: "{0, 0, 0}"; presentingViewController: 0x0; billboardingBehavior: 0x0; scalingBehavior: 0x0; relativeToParent: NO; nonHeritableDepthDisplacement: 0.000000; order: 0.000000; _window._determinedSize: {0, 0}; _window: (null)> to nil or non-supporting UIScene: <UIWindowScene: 0x10a8a0000; role: UISceneSessionRoleImmersiveSpaceApplication; persistentIdentifier: test.test:SFBSystemService-BA3A21A3-D1AB-42E2-8AF0-AE0AB83BE528; activationState: UISceneActivationStateUnattached>. No action taken. Failed to set dependencies on asset 2823930584475958382 because NetworkAssetManager does not have an asset entity for that id. apply fence tx failed (client=0x98490e18) [0x10000003 (ipc/send) invalid destination port] Failed to commit transaction (client=0xa86516e2) [0x10000003 (ipc/send) invalid destination port]

Use case: When SharePlay -ing a fully immersive 3D scene (e.g. a virtual stage), I would like to shine lights on specific Personas, so they show up brighter when someone in the scene is recording the feed (think a camera person in the scene wearing Vision Pro). Note: This spotlight effect only needs to render in the camera person's headset and does NOT need to be journaled or shared. Before I dive into this, my technical question: Can environmental and/or scene lighting affect Persona brightness in a SharePlay? If not, is there a way to programmatically make Personas "brighter" when recording? My screen recordings always seem to turn out darker than what's rendered in environment, and manually adjusting the contrast tends to blow out the details in a Persona's face (especially in visionOS 26).

I didn't find a suggestion box on Swift's website so I'll post it here. SwiftCharts are great but limited. I need more data on a single chart. Candlestick and OHLC type charts would be an excellent addition. Hopefully, influencers from Apple can make that happen. Thanks.

I am new here and would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model. I am able to create from LiDAR scanning 3D mesh and .OBJ file but can not generate .MTL and .JPEG for a texture of 3D model.

I would appreciate help in coding or an explanation what to use in swift for an app which will be able to capture LiDAR scanning and RGB data from taken pictures, generate a 3D mesh, and create .OBJ, .MTL, and .JPEG file set for further manipulation of 3D model.

Hi Looking at the documentation for screenSpaceAmbientOcclusionIntensity, I noticed that it says this is supported on visionOS 1.0+: https://developer.apple.com/documentation/scenekit/scncamera/screenspaceambientocclusionintensity Could someone enlighten me as to how that would work? As far as I know, we don't use an SCNCamera on visionOS. So, what's the idea here? Can we activate SSAO on visionOS?

Hi, since RealityKit 4 now supports Blend Shapes I was wondering if there are any workflow or tooling recommendations to bake/export them into a USDZ. Are Blender or Cinema4D capable to do that out of the box? Should we look into NVIDIA omniverse (https://docs.omniverse.nvidia.com/connect/latest/blender/manual.htm) So far this topic seems very sparsely documented and I would appreciate any hints. Thank you!

Hi, I trying to use Metal cpp, but I have compile error: ISO C++ requires the name after '::' to be found in the same scope as the name before '::' metal-cpp/Foundation/NSSharedPtr.hpp(162): template <class _Class> _NS_INLINE NS::SharedPtr<_Class>::~SharedPtr() { if (m_pObject) { m_pObject->release(); } } Use of old-style cast metal-cpp/Foundation/NSObject.hpp(149): template <class _Dst> _NS_INLINE _Dst NS::Object::bridgingCast(const void* pObj) { #ifdef __OBJC__ return (__bridge _Dst)pObj; #else return (_Dst)pObj; #endif // __OBJC__ } XCode Project was generated using CMake: target_compile_features(${MODULE_NAME} PRIVATE cxx_std_20) target_compile_options(${MODULE_NAME} PRIVATE "-Wgnu-anonymous-struct" "-Wold-style-cast" "-Wdtor-name" "-Wpedantic" "-Wno-gnu" ) May be need to set some CMake flags for C++ compiler ?

Hello, I've been tinkering with PortalComponent on visionOS a bit but noticed that the content of the WorldComponent is always clipped to the mesh geometry of whatever entities have the PortalComponent applied. Now I'm wondering if there is any way or trick to allow contents of the portal to peek out – similar to the Encounter Dinosaurs experience on Vision Pro (I assume it also uses PortalComponent?). I saw that PortalComponent has a clippingPlane property (https://developer.apple.com/documentation/realitykit/portalcomponent/clippingplane-swift.property). But so far I haven't been able to achieve a perceptible visual difference with it. If possible I would like to avoid hacky tricks using duplicate meshes or similar to achieve this. Thanks for any hints!

Hello friends, We are about to launch new app where we want to implement 3d animations that we designed in Cinema 4d and rendered it in Redshift render engine. We worked with sRGB color profile and ACEScg colors profile which both works fine and display correct on Windows machines, but we got to the point where nothing is correct on Apple devices – simply we lost our colors, apple devices displays our 3d animation in a wrong way, since windows works fine. Does anyone know the best workflow from Cinema 4d + Redshift + After Effects to match same colors on both systems and everywhere? We already tried youtube, adobe support, exporting it in EXR, PNG, JPG, LINEAR, TIFF, MP4 etc. – Importing it to After effects with sRGB workflow and ACEScg – it doesnt't work on Macbook, ipad, iphone etc. Please help CHRIS

We have a native iOS app that supports the upload and display of USDZ files. It has been working great since beta (late 2022) and live launch (late 2023) until now. But recently we had reports from some users on Max model phones (14 + 15 Pro Max) at least. When they launch tap and launch a 3D file the Quick Look player is triggered. So far so good. But for affected users the controls along the top of the player - X (close) AR | Object (toggle) and share button - are moving too high up the phone screen and getting stuck (untappable) behind the phone's top status bar (time, camera bug, connection, battery). This means that when they open a USDZ file in AR or 3D view they have to hard-close the app to get out of it again. This doesn't happen when they open a USDZ file from Files, Dropbox etc on their phone (which also uses the Quick Look player). The controls only move up and get stuck when launching a USDZ from within our app. I'm at a loss to figure out what might be causing this on some phones and not all others. And why only when opening a USDZ file from our app! So far we have replicated this issue on a single iphone 14 Pro Max and a 15Pro Max, both running iOS18+ We have tested on other 15Pro Max's on same OS, and Pros, normal iPhones, Minis and are not experiencing the issue. You would think that a USDZ file is a USDZ file and that your iPhone knows what to do with it and open it in the Quick Look player regardless of where you open the file from. Why would the navigation items be moving if you open the USDZ file from within our app, and why only for some select users? We will continue to troubleshoot and test but I wanted to throw this out to the community in case anyone had experienced this or if anyone had any theories that would expedite our testing. Your thoughts are most appeciated! Here is a video showing the expected (correct) behaviour: https://www.dropbox.com/scl/fi/0sp8s4opaf2m4gukkcbrk/How-opening-a-USDZ-should-behave_correct-behaviour.MP4?rlkey=tzzau9x91mwox66gsgguryhep&st=qiykmne9&dl=0 and a screenSHOT attached below of what is happening on one of the affected user's iPhone 15Pro Max.

I'm using the Apple RoomPlan sdk to generate a .usdz file, which works fine, and gives me a 3D scan of my room. But when I try to use Model I/O's MDLAsset to convert that output into an .obj file, it comes out as a completely flat model shaped like a rectangle. Here is my Swift code: let destinationURL = destinationFolderURL.appending(path: "Room.usdz") do { try FileManager.default.createDirectory(at: destinationFolderURL, withIntermediateDirectories: true) try finalResults?.export(to: destinationURL, exportOptions: .model) let newUsdz = destinationURL; let asset = MDLAsset(url: newUsdz); let obj = destinationFolderURL.appending(path: "Room.obj") try asset.export(to: obj) } Not sure what's wrong here. According to MDLAsset documentation, .obj is a supported format and exporting from .usdz to the other formats like .stl and .ply works fine and retains the original 3D shape. Some things I've tried: changing "exportOptions" to parametric, mesh, or model. simply changing the file extension of "destinationURL" (throws error)

Hello Dev team, 3 weeks I'm looking for how I can export a static Cinema 4D objects WITH TEXTURES to Reality Composer Pro ! I can export it directly on USDA format and it works well for the 3D model in Reality Composer Pro, BUT, I can't have the textures on my model. My model is simple not colored ! Of course I expect to have textures applied on the good place and same appearance I've in Cinema 4D. Could you give me a process to do that please ? I'm using Cinema 4D R25 and Last XCode and Reality Composer Pro beta versions. Big big thanks to the one could help me on this. It will unblock many things to me!!!! Cheers Mathis

I am creating a 3D model from multiple images using the photogrammetry session. Now, when the session generates an OBJ file and I measure the distance between two points, the distance is displayed sporadically in different units. Sometimes it's meters, then centimeters, or another unit altogether. How can I tell the photogrammetry session to always create the model in millimeters?

Working on a vision OS app. I've noticed that even when castsShadow is false, performance goes down the drain when there are more than a few dozen entities that have GroundingShadowComponent. I managed to hard crash the Vision Pro with about 200 or so entities that each had two ModelEntities with GroundingShadowComponent attached but set to castShadows = false. My solution is to add and remove the GroundingShadowComponent from entities as needed, but I thought maybe someone at Apple might want to look into this. I don't expect great performance with that many entities casting shadows, but I'd think turning the shadow off would effectively disable the component and not incur a performance penalty.