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,

I have an AR game using ARKit with SceneKit that works just fine in iOS 17. In the iOS 18 betas, the AR background image shows black instead of showing the real world. As a result there's no tracking and obviously the whole game is useless. I narrowed down the issue to showing the Game Center Access Point. My app has ViewController 1 (VC1) showing the main menu and that's where I want to show the GC Access Point. From there you open VC2 which shows a list of levels. Selecting any level will open VC3 which has the ARScene. Following is the code I use to start Game Center in VC1: GKLocalPlayer.local.authenticateHandler = { gcAuthVC, error in let isGameCenterReady = (gcAuthVC == nil) && (error == nil) if let viewController = gcAuthVC { self.present (viewController, animated: true, completion: nil) } if error != nil { print(error?.localizedDescription ?? "") } if isGameCenterReady { GKAccessPoint.shared.location = .topLeading GKAccessPoint.shared.showHighlights = true GKAccessPoint.shared.isActive = true } } When switching to VC2 I run GKAccessPoint.shared.isActive = false so that the Access Point will no longer show in any of the following VCs. I tried running it in VC1, VC2, and again in VC3 - it doesn't change anything. Once I reach VC3, the background is black. If in VC1 I don't run GKAccessPoint.shared.isActive = true, so I don't activate the access point, the behavior is as follows: If I wait until after the Game Center login animation completes and closes on its own and then I proceed to VC2 and VC3, the camera image will show correctly If I quickly move to VC2 before the Game Center login animation has completed, so my code will close it by setting active = false, and then I continue to VC3, I will see the black background problem. So it does look like activating the access point and then de-activating it causes the issue. BTW, if I activate the access point and leave it on in all VCs, the same black background issue persists. Other than that, when I'm in VC3 with the black background and I switch to another app (so my game moves to the background), when it returns to the foreground, the camera suddenly shows the real world correctly! I tried to manually reset the AR session by pausing and restarting it, but that didn't change anything. Also, when I check with the debugger, it looks like when the app comes back to the foreground it also doesn't run the session start code. But something does seem to reset itself so I wonder what that is. Maybe I could trigger the same manually in my cdoe??? I repeat that everything works just fine in iOS 17 and below. This problem only started with the iOS 18 beta (currently on beta 5, but it started in some of the previous betas as well). So could this be a bug in iOS 18? As a workaround I could check the iOS version and if it's iOS18 not activate the access point, hoping that the user will not jump to VC2 too quickly, and show my own button which will open Game Center. But I'd rather give the users the full experience with their own avatar and the highlights showing up. Plus, certainly some users will move quickly to VC2 and that will be an awful experience. Any help would be greatly appreciated. Thanks!

I recently published my first game on the App Store. It uses SceneKit with a SpriteKit overlay. All crashes Xcode downloaded for it so far are related to some SpriteKit/SceneKit internals. The most common crash is caused by SKCShapeNode::_NEW_copyRenderPathData. What could cause such a crash? crash.crash While developing this game (and the BoardGameKit framework that appears in the crash log) over the years I experienced many crashes presumably caused by the SpriteKit overlay (I opened a post SceneKit app randomly crashes with EXC_BAD_ACCESS in jet_context::set_fragment_texture about such a crash in September 2024), and other people on the internet also mention that they experience crashes when using SpriteKit as a SceneKit overlay. Should I use a separate SKView and lay it on top of SCNView rather than setting SCNView.overlaySKScene? That seemed to solve the crashes for a guy on stackoverflow, but is it also encouraged by Apple? I know SceneKit is deprecated, but according to Apple critical bugs would still be fixed. Could this be considered a critical bug?

I noticed that MTLPixelFormat has this cases: case r32Float = 55 case rg32Float = 105 case rgba32Float = 125 But no case rgb32Float. What's the reason for such a discrimination?

For an app of mine I use CGSetDisplayTransferByTable to adjust the gamma table of the device. Since macOS Tahoe, these modifications are silently ignored. The display's actual gamma curve remains unchanged despite the API reporting successful completion. I've filed a FB for it a few weeks ago, and would love to figure out what could be causing this. FB18559786

اريد انشاء لعبه في ابل ستور و تكون اول صفحه تكون شروط و الاحكام و خيار بدا اللعبه200 فئات من السعوديه من مسلسل من العب من بنات و بس وقطر و الإمارات وانمي ومسلسلات تركيه و السياحه و الدول وشركات عالميه و شركات كترونيه

We are developing a video processing app that applies CIFilter chains to video frames. To not force the user to keep the app foregrounded, we were happy to see the introduction of BGContinuedProcessingTask to continue processing when backgrounded. With iOS 26, I was excited to see the com.apple.developer.background-tasks.continued-processing.gpu entitlement, which should allow GPU access in the background. Even the article in the documentation provides "exporting video in a film-editing app" or "applying visual filters (HDR, etc) or compressing images for social media posts" as use cases. However, when I check BGTaskScheduler.shared.supportedResources.contains(.gpu) at runtime, it returns false on every iPhone I've tested (including iPhone 15 Pro and iPhone 16 Pro). From forum responses I've seen, it sounds like background GPU access is currently limited to iPad only. If that's the case, I have a few questions: Is this an intentional, permanent limitation — or is iPhone support planned for a future iOS release? What is the recommended approach for GPU-dependent background work on iPhone? My custom CIKernels are written in Metal (as Apple recommends since CIKL is deprecated), but Metal CIKernels cannot fall back to CPU rendering. This creates a situation where Apple's own deprecation guidance (migrate to Metal) conflicts with background processing realities (no GPU on iPhone). Should developers maintain deprecated CIKL kernel versions alongside Metal kernels purely as a CPU fallback for background execution? That feels like it defeats the purpose of the migration. It seems like a gap in the platform: the API exists, the entitlement exists, but the hardware support isn't there for the most common device category. Any clarity on Apple's direction here would be very helpful.

I'm updating our app to support metal 4, but the metal 4 types don't seem to get recognized when targeting simulator. Is it known if metal 4 will be supported in the near future, or am I setting up the app wrong?

I have an app that uses GameController to read the inputs of a connected JoyCon. However, the controller also interacts with the OS. For example, when I press the Home button on the controller, it brings me to the home of my Vision Pro. Is it possible to disable this interaction while still being able to read the controller inputs inside my app?

Added achievements to my approved app. Added them for the next release version, which I am running in simulator. When I look at the Achievements page, I can see that there are 17 Achievements available (correct), but they all show as hidden, despite checking the "No" box in App Store Connect.

I've been playing with the new GameSave API and cannot get it to work. I followed the 3-step instructions from the Developer video. Step 2, "Next, login to your Apple developer account and include this entitlement in the provisioning profile for your game." seems to be unnecessary, as Xcode set this for you when you do step 1 "First add the iCloud entitlement to your game." Running the app on my device and tapping "Load" starts the sync, then fails with the error "Couldn’t communicate with a helper application." I have no idea how to troubleshoot this. Every other time I've used CloudKit it has Just Worked™. Halp‽ Here is my example app: import Foundation import SwiftUI import GameSave @main struct GameSaveTestApp: App { var body: some Scene { WindowGroup { GameView() } } } struct GameView: View { @State private var loader = GameLoader() var body: some View { List { Button("Load") { loader.load() } Button("Finish sync") { Task { try? await loader.finish() } } } } } @Observable class GameLoader { var directory: GameSaveSyncedDirectory? func stateChanged() { let newState = withObservationTracking { directory?.state } onChange: { Task { @MainActor [weak self] in self?.stateChanged() } } print("State changed to \(newState?.description ?? "nil")") switch newState { case .error(let error): print("ERROR: \(error.localizedDescription)") default: _ = 0 // NOOP } } func load() { print("Opening gamesave directory") directory = GameSaveSyncedDirectory.openDirectory() stateChanged() } func finish() async throws { print("finishing syncing") await directory?.finishSyncing() } }

I have something like this drawing in an MTKView (see at bottom). I am finding it difficult to figure out when can the Swift-land resources used in making the MTLBuffer(s) be released? Below, for example, is it ok if args goes out of scope (or is otherwise deallocated) at point 1, 2, or 3? Or perhaps even earlier, as soon as argsBuffer has been created? I have been reading through various articles such as Setting resource storage modes Choosing a resource storage mode for Apple GPUs Copying data to a private resource but it's a lot to absorb and I haven't been really able to find an authoritative description of the required lifetime of the resources in CPU land. I should mention that this is Metal 4 code. In previous versions of Metal, the MTLCommandBuffer had the ability to add a completion handler to be called by the GPU after it has finished running the commands in the buffer but in Metal 4 there is no such thing (it it were even needed for the purpose I am interested in). Any advice and/or pointers to the definitive literature will be appreciated. guard let argsBuffer = device.makeBuffer(bytes: &args,... argumentTable.setAddress(argsBuffer.gpuAddress, ... encoder.setArgumentTable(argumentTable, stages: .vertex) // encode drawing renderEncoder.draw... ... encoder.endEncoding() // 1 commandBuffer.endCommandBuffer() // 2 commandQueue.waitForDrawable(drawable) commandQueue.commit([commandBuffer]) // 3 commandQueue.signalDrawable(drawable) drawable.present()

When running my game in the Unity Editor on Windows platform I get an error: DllNotFoundException: GameKitWrapper assembly:<unknown assembly> type:<unknown type> member:(null) Apple.GameKit.DefaultNSErrorHandler.Init () (at ./Library/PackageCache/com.apple.unityplugin.gamekit@0abcad546f73/Source/DefaultHandlers.cs:35) This is because GameKitWrapper dynamically linked library is not available under Windows platform. Besides, "Apple Build Settings" are declared under UNITY_EDITOR_OSX and also not available under Windows platform. Does anyone managed to solve this?

Is the pseudocode below thread-safe? Imagine that the Main thread sets the CAMetalLayer's drawableSize to a new size meanwhile the rendering thread is in the middle of rendering into an existing MTLDrawable which does still have the old size. Is the change of metalLayer.drawableSize thread-safe in the sense that I can present an old MTLDrawable which has a different resolution than the current value of metalLayer.drawableSize? I assume that setting the drawableSize property informs Metal that the next MTLDrawable offered by the CAMetalLayer should have the new size, right? Is it valid to assume that "metalLayer.drawableSize = newSize" and "metalLayer.nextDrawable()" are internally synchronized, so it cannot happen that metalLayer.nextDrawable() would produce e.g. a MTLDrawable with the old width but with the new height (or a completely invalid resolution due to potential race conditions)? func onWindowResized(newSize: CGSize) { // Called on the Main thread metalLayer.drawableSize = newSize } func onVsync(drawable: MTLDrawable) { // Called on a background rendering thread renderer.renderInto(drawable: drawable) }

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.

Hello If you add a ModelEntity to a world inside a portal, the drawing of the model will be occluded properly to the portal bounds. However the invisible shape of the InputTargetComponent and CollisionComponent are not occluded. They are able to cross the portal, and if you have gestures on your ModelEntity you can trigger them in areas outside the portal bounds. This happens even if the ModelEntity has no PortalCrossingComponent.

I wanted to drag EntityA while also dragging EntityB independently. I've tried to separate them by entity but it only recognizes the latest drag gesture RealityView { content, attachments in ... } .gesture( DragGesture() .targetedToEntity(EntityA) .onChanged { value in ... } ) .gesture( DragGesture() .targetedToEntity(EntityB) .onChanged { value in ... } ) also tried using the simultaneously but didn't work too, maybe i'm missing something .gesture( DragGesture() .targetedToEntity(EntityA) .onChanged { value in ... } .simultaneously(with: DragGesture() .targetedToEntity(EntityB) .onChanged { value in ... } )

Dear Apple Color Management Team, I’m a professional visual creator working on color-critical photo and graphic projects using macOS (currently 26.1 Tahoe). In recent macOS releases, LUT-based ICC display profiles (such as XYZ LUT + Matrix types generated by DisplayCAL or professional spectrophotometers) can no longer be installed or activated via ColorSync. This limitation significantly affects professional workflows in photography, graphic design, prepress, and video color grading — fields that rely on precise display profiling. The current workaround (converting LUT profiles to simple shaper/matrix ICC v2) results in less accurate tone response and color reproduction, particularly in the dark range and wide-gamut displays. I kindly request Apple to restore or re-enable the ability to install and use ICC v2/v4 LUT-based display profiles under ColorSync, as was possible on macOS Monterey and Ventura. This would allow professionals to continue using trusted calibration tools such as DisplayCAL, X-Rite i1Profiler, and Calibrite Profiler to achieve accurate color management. macOS is widely used in professional creative industries, and restoring this feature would be a huge help for countless photographers, designers, and colorists. Thank you for your attention and commitment to professional users. Best regards, Richárd Deutsch Professional Photographer https://riccio.hu/ MacBook Pro (M4 Pro, macOS 26.1)

Hi all, I'm encountering an issue with Metal raytracing on my M5 MacBook Pro regarding Instance Acceleration Structure (IAS). Intersection tests suddenly stop working after a certain point in the sampling loop. Situation I implemented an offline GPU path tracer that runs the same kernel multiple times per pixel (sampleCount) using metal::raytracing. Intersection tests are performed using an IAS. Since this is an offline path tracer, geometries inside the IAS never changes across samples (no transforms or updates). As sampleCount increases, there comes a point where the number of intersections drops to zero, and remains zero for all subsequent samples. Here's a code sketch: let sampleCount: UInt16 = 1024 for sampleIndex: UInt16 in 0..<sampleCount { // ... do { let commandBuffer = commandQueue.makeCommandBuffer() // Dispatch the intersection kernel. await commandBuffer.completed() } do { let commandBuffer = commandQueue.makeCommandBuffer() // Use the intersection test results from the previous command buffer. await commandBuffer.completed() } // ... } kernel void intersectAlongRay( const metal::uint32_t threadIndex [[thread_position_in_grid]], // ... const metal::raytracing::instance_acceleration_structure accelerationStructure [[buffer(2)]], // ... ) { // ... const auto result = intersector.intersect(ray, accelerationStructure); switch (result.type) { case metal::raytracing::intersection_type::triangle: { // Write intersection result to device buffers. break; } default: break; } Observations Encoding both the intersection kernel and the subsequent result usage in the same command buffer does not resolve the problem. Switching from IAS to Primitive Acceleration Structure (PAS) fixes the problem. Rebuilding the IAS for each sample also resolves the issue. Intersections produce inconsistent results even though the IAS and rays are identical — Image 1 shows a hit, while Image 2 shows a miss. Questions Am I misusing IAS in some way ? Could this be a Metal bug ? Any guidance or confirmation would be greatly appreciated.

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.