Hello there, I'm having trouble matching what I see in the scenekit editor and the output of the resulting scene in a scnview. For a glitter effect I have set a high value on the diffuse intensity which looks fine in the editor but when running the game the colors are much darker. To see if the intensity value is merely capped I have set the same multiplier on the hat below - but it is blown out which looks to me like there is some grading going on I have tried to switch on hdr rendering but that didn't make a difference. I tried disabling linear rendering and that simply made everything darker still - which I expect. Does someone have an idea what else this could be? What rendering is the scenekit editor using and how can I match it? Interestingly when I take a screenshot of the editor window for this post, the image is also blown out... what is going on? :) Thanks so much for any pointers, Seb

In my project I need to do the following: In runtime create metal Dynamic library from source. In runtime create metal Executable library from source and Link it with my previous created Dynamic library. Create compute pipeline using those two libraries created above. But I get the following error at the third step: Error Domain=AGXMetalG15X_M1 Code=2 "Undefined symbols: _Z5noisev, referenced from: OnTheFlyKernel " UserInfo={NSLocalizedDescription=Undefined symbols: _Z5noisev, referenced from: OnTheFlyKernel } import Foundation import Metal class MetalShaderCompiler { let device = MTLCreateSystemDefaultDevice()! var pipeline: MTLComputePipelineState! func compileDylib() -> MTLDynamicLibrary { let source = """ #include <metal_stdlib> using namespace metal; half3 noise() { return half3(1, 0, 1); } """ let option = MTLCompileOptions() option.libraryType = .dynamic option.installName = "@executable_path/libFoundation.metallib" let library = try! device.makeLibrary(source: source, options: option) let dylib = try! device.makeDynamicLibrary(library: library) return dylib } func compileExlib(dylib: MTLDynamicLibrary) -> MTLLibrary { let source = """ #include <metal_stdlib> using namespace metal; extern half3 noise(); kernel void OnTheFlyKernel(texture2d<half, access::read> src [[texture(0)]], texture2d<half, access::write> dst [[texture(1)]], ushort2 gid [[thread_position_in_grid]]) { half4 rgba = src.read(gid); rgba.rgb += noise(); dst.write(rgba, gid); } """ let option = MTLCompileOptions() option.libraryType = .executable option.libraries = [dylib] let library = try! self.device.makeLibrary(source: source, options: option) return library } func runtime() { let dylib = self.compileDylib() let exlib = self.compileExlib(dylib: dylib) let pipelineDescriptor = MTLComputePipelineDescriptor() pipelineDescriptor.computeFunction = exlib.makeFunction(name: "OnTheFlyKernel") pipelineDescriptor.preloadedLibraries = [dylib] pipeline = try! device.makeComputePipelineState(descriptor: pipelineDescriptor, options: .bindingInfo, reflection: nil) } }

I’m running into unexpected problems with the Unity GameKit plugin setup with the new Activities. I didn’t see anyone else mentioning these issues, so my guess is that it’s a problem with my setup. The authentication (GKLocalPlayer.Authenticate()) works as expected, but any call to the new GameActivity functionality (e.g. GKGameActivityDefinition.LoadGameActivityDefinitions() or GKGameActivity.WantsToPlay) gives me an exception with a 'UnsupportedOperationForOSVersion' reason despite it running on an iOS 18.6.1 device. I’m using a completely empty Unity 2022.3.62f1 project that only contains the official authentication example, followed by an event handler for activities from another example and the Unity core and gamekit plugins. The setup: macOS 15.6 Xcode 26 beta 6 (also tried with 5) Physical iPhone device running iOS 18.6.1 Unity 2022.3.62f1, which satisfies the requirements Unity plugin, Xcode setup, and build steps: I Followed the official beta branch build steps for Unity plugins with python3 build.py -m iOS iPhoneSimulator macOS -p Core GameKit which ran through after a slight modification for the macOS target that somehow contained an unknown team reference for the GameKitWrapper project, which I changed to not reference a team and use ‘sign to run locally’, as was the case for the other packages. As far as I understood the macOS version is not strictly necessary either way just for running it on a local iOS device(?) I Imported these as tarball packages into the empty Unity 2022.3.62f1 project as per the official instructions, which seems to work as expected Added a single script with the mentioned example code added in a MonoBehavior.Start Building in Unity works as expected as well, creating the Xcode project The Unity-iPhone target has the GameKit framework linked (’do not embed’) and the GameCenter capability was added automatically as expected The GameKit framework seems to not be added to the UnityFramework target, but I don’t think this is necessary? Quickly testing this with the GameKit framework added there as well didn’t make a difference The linked GameKit framework is indeed the expected Xcode 26 beta version I can then build and run this on the physical iPhone iOS 18.6.1 device, where I get an ‘UnsupportedOperationForOSVersion’ as soon as I try to subscribe to deeplinking events (GKGameActivity.WantsToPlay) or use other GameKit Activity functionality from the official examples: // log showing that it's actually running on iOS 18.6: [Apple.Core Plug-In Runtime] Availability Runtime Environment: iOS 18.6 Apple.Core.Availability:OnApplicationStart() // and the exception I get: GameKitException: Code=-7 Domain=GKErrorDomain Description=The operation couldn’t be completed. (GKErrorDomain error -7.) (UnsupportedOperationForOSVersion) at Apple.GameKit.DefaultNSErrorHandler.ThrowNSError (System.IntPtr nsErrorPtr) [0x00000] in <00000000000000000000000000000000>:0 Rethrow as TypeInitializationException: The type initializer for 'Apple.GameKit.GKGameActivity' threw an exception. I unfortunately didn’t find any clues as to why this happens and how to resolve it on this forum or otherwise. Changing the minimum iOS version - up to 18.6 from the previously used (Unity export default) 12.0 for any and all targets - did not yield a different result I'd rather not update the phone to use the iOS 26 beta, though as far as I understood this is not necessary Any pointers to what I might be missing or doing wrong are greatly appreciated! Thank you very much in advance!

This is the first time I have tried adding achievements to my games. The online documentation says: "Before you can access achievements in your code, you can configure them in Xcode and sync the configuration updates you make with App Store Connect. Begin configuring achievements by creating a GameKit configuration file. In Xcode, choose File > New > File from Template. Select GameKit File, and click Next. In the sheet that appears, enter a name for the configuration and click Create." Sounds easy - except Xcode 16.2 does not have a GameKit File as one of the Templates. Please advise on how to proceed and it would be nice if the documentation were updated.

Hi, is there any way to use front camera to do the motion capture? I want recognize if the user raised there hands up with the front camera on iPhone. I was able to do it with the back camera, not the front. Also, if there is any sample code, or document, I would be super happy. Waiting for your reply!!

New to achievements. I added them in App Store Connect and want to test them. Apple Documentation says this: "Before you begin testing your GameKit configuration, you need to enable Debug Mode. In Xcode, choose Product > Scheme > Edit Scheme. From the Run configuration, select Options and toggle Enable Debug Mode. To begin testing your achievement configuration, open the game Progress Manager. In Xcode, choose Debug > GameKit > Manage Game Progress." Sounds easy enough, but there is no "GameKit" under Debug in Xcode 16.2.

Due to the release of ProMotion devices, the system may switch frame rates in certain scenarios, resulting in the loss of reference value for data collected through CADisplayLink callbacks at a fixed 60Hz frame rate. We cannot distinguish whether the slow callback of CADisplayLink is due to a stutter or a system switch in frame rate. I know Hitch Time Ratio, but I can't use this scheme for some reasons. How can I distinguish between stuck and frame rate gear shift in CADisplaylink callback? In iOS 15, CADisplayLink.preferredFrameRateRange.preferred always returns 0, while minimum and maximum do change. Can I use these minimum and maximum range values as criteria to distinguish between frame rate switching and stuttering?

Hello — I shipped an App Store build that signs in to Game Center using the Apple Unity Plugins (GameKit). The login banner appears, but my app still doesn’t show up in Game Center’s “All activity” (You started playing XXX 2d ago) What I’ve done Call await GKLocalPlayer.Authenticate(); “Game Center” is enabled for the current version in App Store Connect Confirmed: other App Store games do appear under “All Activity” on the same device/account Timeline: This is the first version that enables Game Center (not the app’s first release), and it has been about 2 hours since this build went live. Questions Is authentication alone sufficient for “Recently Played,” or is at least one Game Center component (leaderboards, achievements, activities, multiplayer) required? Is there a typical propagation delay before “Recently Played” starts showing a newly enabled app/version? Is there anything else I should configure in App Store Connect or entitlements to make “Recently Played” visible? Thanks for any help.

I am interested in learning the Metal framework for rendering development. However, most of Apple’s official documentation uses Objective-C code. Therefore, I am seeking guidance on whether it is more advantageous for me to focus solely on learning Swift to gain proficiency in Metal.

I use SCNScene.write To file ".usdz", then open the ".usdz" by SCNScene.url , all Nodes color fades. Export and load only once. The fading is not obvious. Return and repeat 4 or 5 times. It is obvious that the color is inconsistent with the original color and has become much lighter.

Hello! I'm developing a GPU (shader) language, where I aim to target multiple backends with a common frontend. I wanted to avoid having to round trip through Metal, and go straight to IR just like I have with SPIRV, in order to have a fast and efficient compilation process. I've been looking for a reference page where I can read about Metals IR, and as far as I'm aware, it exists, but I can't seem to find it anywhere. Furthermore, if such a reference is available, is there also a toolkit where I can run validation on the output IR, and perhaps even run optimizations, much like spv-tools for SPIRV? Any help would be appreciated! Thanks, Gustav

After following the instructions here: https://developer.apple.com/metal/cpp/ I attempted building my project and Xcode presented several errors. In essence it's complaining about some redeclarations in the Metal-CPP headers. NSBundle.hpp and NSError.hpp are included in the metal-cpp/foundation directory from the metal-cpp download. Any help in getting these issues resolved is appreciated. Thanks!

Hello, Apple! This post is a bug report for Metal driver in MacOS Sequoia. I'm working on opensource game engine and one of my users reported a bug, on "MacOS Sequoia" + "AMD Radeon RX 6900 XT".  Engine crashes, when liking a compute pipeline, with following NSError: "Compiler encountered an internal error: I" Offended shader (depth aware blur): https://shader-playground.timjones.io/27565de40391f62f078c891077ba758c On my end, compiling same shader on M1 (Sonoma) or with offline compiler doesn't reproduce the issue. Post with bug-report on github: https://github.com/Try/OpenGothic/issues/712 Looking forward for your help and driver fix ;)

I have a bare-bones Metal app setup where I attach a CAMetalLayer to a window that inherits from a NSWindow with a custom delegate. Everything else is vanilla. I'm also using metal-cpp and metal shader converter. I'm running into a issue where the application runs fine in the beginning, but once I resize the window, it starts hitching. It turns out that [CAMetalLayer nextDrawable:] frequently (but not always) takes around a full second (plus or minus a few milliseconds) to return once drawableSize has been updated. I've tried setting allowsNextDrawableTimeout to false which doesn't work; it returns a valid drawable after a second instead of nil. Setting displaySyncEnabled to false reduces the likelihood of this happening to around 50% from 90%+ but does not eliminate it. Setting maximumDrawableCount to 2 or 3 does not seem to make a difference. By dumping the resource IDs of the returned textures I've noticed something interesting: Before resizing, the layer seems to shuffle between 2 textures or at least 2 resource IDs, but after resizing it starts to create new textures for each returned drawable. Occasionally it seems to reuse a previous resource ID, but it does not seem to have anything to do with whether the method returns quickly or not. Why does this happen, and how can I fix it? Should I create a new CAMetalLayer when resizing the window instead of updating drawableSize?

If I compile a compute kernel with a call to texture.read(), it fails with the following error: "Error Domain=AGXMetalG13X Code=3 "Encountered unlowered function call to air.get_read_sampler" UserInfo={NSLocalizedDescription=Encountered unlowered function call to air.get_read_sampler}." This error occurs on both macOS and iOS 26 Beta 5, but not when running on a simulator or in a playground. It does not occur on a macOS Sequoia VM. It occurs whether I use the old metal 3 or new metal 4 compilation method. A workaround would be to use a sampler, but according to the feature tables, all platforms support reading from textures of all formats. Below is a minimal example which produces the error: let device = MTLCreateSystemDefaultDevice()! let library = device.makeDefaultLibrary()! let computeFunction = library.makeFunction(name: "compute_test")! do { let pipeline = try device.makeComputePipelineState(function: computeFunction) debugPrint(pipeline) } catch { debugPrint("Metal 3 failed with error:\n\(error)") } #import <metal_stdlib> using namespace metal; kernel void compute_test(uint2 gid [[thread_position_in_grid]], texture2d<float, access::read> in [[texture(0)]], texture2d<float, access::write> out [[texture(1)]]) { out.write(in.read(gid), gid); } I filed feedback FB19530049.

Hi there, Is it possible to customize the Metal Performance HUD on Apple TV, similar to how it can be done on iPhone & iPad? Would like to see things like Compiled Shaders for my Apps on tvOS .

Now that SceneKit has been marked as soft deprecated, is there a planned date or timeframe when it will be completely removed from iOS? I’m concerned about how long my existing SceneKit-based game will continue to work, especially as an indie developer without the resources for a quick rewrite to RealityKit.

Hi, I am a Multimedia and Graphics researcher and I am wondering if OpenGL API and drivers will be removed after appleOS 26? macOS 26 iOS 26 iPadOS 26 visionOS 26 I am asking this because most of the libraries I use depends on OpenGL. Like CGAL, libigl, immediate mode ui, nanovg, nanogui, bullet physics. Transitioning from Vulkan and metal while using and learning those libraries is just not viable. I would like to ask you that. I am the sole developer and I just want to ask you that. Regards.

I'm experiencing a specific issue where when using any of the MacOS 26 Tahoe betas with Low Power Mode enabled and using Vsync in fullscreen, my application framerate gets limited to a hard 30 fps. I have not experienced this on any older OS. For example Low Power Mode on 13.6 Ventura with Vsync fullscreen lets my application run at full 60 fps without issues. Is this a bug or a change in behavior of Low Power Mode on Tahoe? My application is 3D, runs at 60 fps and is sensitive to tearing, so I need Vsync and it is mostly utilized in fullscreen. And Low Power Mode is a default for many Macs, so default experience on Tahoe currently is a halved 30 fps. However there also seems to be inconsistencies of on which machines this happens, but older OSes are always fine.

Hi, I'm rewriting my game from SceneKit to RealityKit, and I'm having trouble implementing the following scenario: I tap on the iPhone screen to select an Entity that I want to drag. If an Entity was tapped, it should then be possible to drag it left, right, etc. SceneKit solution: func CGPointToSCNVector3(_ view: SCNView, depth: Float, point: CGPoint) -> SCNVector3 { let projectedOrigin = view.projectPoint(SCNVector3Make(0, 0, Float(depth))) let locationWithz = SCNVector3Make(Float(point.x), Float(point.y), Float(projectedOrigin.z)) return view.unprojectPoint(locationWithz) } and then I was calling: SCNView().hitTest(location, options: [SCNHitTestOption.firstFoundOnly:true]) the code was called inside of the UIPanGestureRecognizer in my UIViewController. Could I reuse that code or should I go with the SwiftUI approach - something like that: var body: some View { RealityView { .... } .gesture(TapGesture().onEnded { }) ? I already have this code: @State private var location: CGPoint? .onTapGesture { location in self.location = location } I'm trying to identify the entity that was tapped within the RealityView like that: RealityView { content in let box: ModelEntity = createBox() // for now there is only one box, however there will be many boxes content.add(box) let anchor = AnchorEntity(world: [0, 0, 0]) content.add(anchor) _ = content.subscribe(to: SceneEvents.Update.self) { event in //TODO: find tapped entity, so that it could be dragged inside of the DragGesture() } Any help would be appreciated. I also noticed that if I create a TapGesture like that: TapGesture(count: 1) .targetedToAnyEntity() and add it to my view using .gesture() then it is not triggered.