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.

I am building a MacOS desktop app (https://anukari.com) that is using Metal compute to do real-time audio/DSP processing, as I have a problem that is highly parallelizable and too computationally expensive for the CPU. However it seems that the way in which I am using the GPU, even when my app is fully compute-limited, the OS never increases the power/performance state. Because this is a real-time audio synthesis application, it's a huge problem to not be able to take advantage of the full clock speeds that the GPU is capable of, because the app can't keep up with real-time. I discovered this issue while profiling the app using Instrument's Metal tracing (and Game tracing) modes. In the profiling configuration under "Metal Application" there is a drop-down to select the "Performance State." If I run the application under Instruments with Performance State set to Maximum, it runs amazingly well, and all my problems go away. For comparison, when I run the app on its own, outside of Instruments, the expensive GPU computation it's doing takes around 2x as long to complete, meaning that the app performs half as well. I've done a ton of work to micro-optimize my Metal compute code, based on every scrap of information from the WWDC videos, etc. A problem I'm running into is that I think that the more efficient I make my code, the less it signals to the OS that I want high GPU clock speeds! I think part of why the OS is confused is that in most use cases, my computation can be done using only a small number of Metal threadgroups. I'm guessing that the OS heuristics see that only a small fraction of the GPU is saturated and fail to scale up the power/clock state. I'm not sure what to do here; I'm in a bit of a bind. One possibility is that I intentionally schedule busy work -- spin threadgroups just to waste energy and signal to the OS that I need higher clock speeds. This is obviously a really bad idea, but it might work. Is there any other (better) way for my app to signal to the OS that it is doing real-time latency-sensitive computation on the GPU and needs the clock speeds to be scaled up? Note that game mode is not really an option, as my app also runs as an AU plugin inside hosts like Garageband, so it can't be made fullscreen, etc.

Hey all! I'm got my hands on a refurbished mac mini m1 and already diving into metal. At the moment, i'm currently studying graphics programming with opengl and got to a point where I can almost create a 3d cube. However, I noticed there aren't many tutorials for metal cpp but rather demos. One thing I love about graphic programming, is skinning/skeletal animation. At the moment, I can't find any sources or tutorials on how to load skeletal animations into metal-cpp. So, if I create my character in blender and had all types of animations all loaded into a .FBX or maybe .DAE and load this into metal api with metal-cpp, how can I go on about how this works?

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.

Hello, we are working on a iOS game project, as progress, the project grows larger and larger. Because we are using other game dependencies and libraries, here larger and larger refers to the whole project, and our source files integrated and compiled by Xcode are not many. Now, it seems we hit a bottleneck, when I add new files or functions to the previous files to implement a new feature, Xcode compile stucks(stops), it's Indexing | Initializing datastore forever, cannot produce a final build. macOS 15.1, Xcode 16.2 Can you provide any solutions to solve this problem? Also submitted Feedback ID #FB18432749

Hey folks, I have a legacy game that is running OpenGL ES - and it no longer works on the simulators that are running Apple Silicon, ie iPhone 15 Pro, or the 13" iPads. And yes, i'm also running on Apple Silicon (M1 Max). The apps work fine on the actual devices, but the simulator crashes on any glDrawElements with a stack that looks like the following: I have not yet seen an announcement about this not working but i've seen mention in other apps of stopping to support GL (https://github.com/maplibre/maplibre-native/issues/2351) Can anyone shed some light? I'm obviously going to try to fix it, or find a recent sample app from which to start to see what might be up. Or move to metal, but i hadn't bargained for that level of effort atm ;) Any suggestions appreciated!

I have two apps released -- ReefScan and ReefBuild -- that are based on the WWDC21 sample photogrammetry apps for iOS and MacOS. Those run fine without LiDAR and are used mostly for underwater models where LiDAR does not work at all. It now appears that the updated photogrammetry session requires LiDAR data, and building my app on current xcode results in a non-working app. Has the "old" version of photgrammetry session been broken by this update? It worked very well previously so I would hate to see this regression to needing LiDAR. Most of my users do not have that.

Hello everyone, I must have missed something but why isn't there a depthAttachmentPixelFormat to the new Metal 4 MTL4RenderPipelineDescriptor, unlike the old MTLRenderPipelineDescriptor? So how do you set the depth pixel format? Thanks in advance!

How to create a beautiful fire animation using Swift? Which API is better to use?

Hi, What's the best way to handle drastic changes in scene charateristics with the new MTLFXTemporalDenoisedScaler? Let's say a visible object of the scene radically changes its material properties. I can modify the albedo and roughness textures consequently. But I suspect the history will be corrupted. Blending visual information between the new frame and the previous ones might be a nonsense. I guess the problem should be the same when objects appear or disappear instantly. Is the upsacler manage these events for us (by lowering blending), or should we use the reactive or the denoise strength mask or something like that to handle them?

During regular use, RealityKit generates an excessive amount of internal logging that is not actionable by third party developers. When developing an iOS RealityKit/ARKit app, this makes the Xcode console challenging to use for regular work. (FB19173812) See screenshots below. Xcode does have an option for filtering out logging from specific SDKs, but enabling this feature to suppress the logging of RealityKit and related SDKs like PHASE is something developers have to do dozens of times each day. After a year of developing a RealityKit app, this process becomes frustrating. If SDKs like Foundation, UIKit, and SwiftUI generated as much logging as RealityKit and related SDKs, Xcode's console would be unusable. Is there any way to disable the logging of RealityKit and PHASE permanently? Thank you for any help you provide.

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

I am currently developing a mobile and server-side application using the new ObjectCaptureSession on iOS and PhotogrammetrySession on MacOS. I have two questions regarding the newly updated APIs. From WWDC23 session: "Meet Object Capture for iOS", I know that the Object Capture API uses Point Cloud data captured from iPhone LiDAR sensor. I want to know how to use the Point Cloud data captured on iPhone ObjectCaptureSession and use it to create 3D models on PhotogrammetrySession on MacOS. From the example code from WWDC21, I know that the PhotogrammetrySession utilizes depth map from captured photo images by embedding it into the HEIC image and use those data to create a 3D asset on PhotogrammetrySession on MacOS. I would like to know if Point Cloud data is also embedded into the image to be used during 3D reconstruction and if not, how else the Point Cloud data is inserted to be used during reconstruction. Another question is, I know that Point Cloud data is returned as a result from request to the PhtogrammetrySession.Request. I would like to know if this PointCloud data is the same set of data captured during ObjectCaptureSession from WWDC23 that is used to create ObjectCapturePointCloudView. Thank you to everyone for the help in advance. It's a real pleasure to be developing with all the updates to RealityKit and the Object Capture API.

Hello ladies and gentlemen, I'm writing a simple renderer on the main actor using Metal and Swift 6. I am at the stage now where I want to create a render pipeline state using asynchronous API: @MainActor class Renderer { let opaqueMeshRPS: MTLRenderPipelineState init(/*...*/) async throws { let descriptor = MTLRenderPipelineDescriptor() // ... opaqueMeshRPS = try await device.makeRenderPipelineState(descriptor: descriptor) } } I get a compilation error if try to use the asynchronous version of the makeRenderPipelineState method: Non-sendable type 'any MTLRenderPipelineState' returned by implicitly asynchronous call to nonisolated function cannot cross actor boundary Which is understandable, since MTLRenderPipelineState is not Sendable. But it looks like no matter where or how I try to access this method, I just can't do it - you have this API, but you can't use it, you can only use the synchronous versions. Am I missing something or is Metal just not usable with Swift 6 right now?

I would love to use Background GPU Access to do some video processing in the background. However the documentation of BGContinuedProcessingTaskRequest.Resources.gpu clearly states: Not all devices support background GPU use. For more information, see Performing long-running tasks on iOS and iPadOS. Is there a list available of currently released devices that do (or don't) support GPU background usage? That would help to understand what part of our user base can use this feature. (And what hardware we need to test this on as developers.) For example it seems that it isn't supported on an iPad Pro M1 with the current iOS 26 beta. The simulators also seem to not support the background GPU resource. So would be great to understand what hardware is capable of using this feature!

I'm trying to build an MDLMesh then add normals let mdlMesh = MDLMesh.newBox(withDimensions: SIMD3<Float>(1, 1, 1), segments: SIMD3<UInt32>(2, 2, 2), geometryType: MDLGeometryType.triangles, inwardNormals:false, allocator: allocator) mdlMesh.addNormals(withAttributeNamed: MDLVertexAttributeNormal, creaseThreshold: 0) When I render the mesh, some normals are (0,0,0). I don't know if the problem is in the mesh, or in the conversion to MTKMesh. Is there a way to examine an MDLMesh with the geometry viewer? When I look at the variable values for my mdlMesh I get this: Not too useful. I don't know how to track down the normals. What's the best way to find out where the normals getting broken?

Our application is trying to read all resolutions of an external monitor. We have observed that, for the external monitor there is a mismatch in resolution list in our application and the resolution list in system settings. We are using the apple API "CGDisplayCopyAllDisplayModes" to read the resolutions.

Hi everyone, I'm building a native iOS app using Unreal Engine 5.6 with Firebase for authentication and Firestore. The app uses a MetaHuman avatar and is meant to run as a standalone UE app on iPhone. I'm using this Firebase wrapper: 👉 https://pandoa.github.io/FirebaseFeatures/ I've followed all the steps, including: Adding GoogleService-Info.plist to the Xcode project and ensuring it’s in the correct target Calling FIRApp.configure() in AppDelegate Verifying the plist is bundled correctly However, the app crashes on launch, and Firebase does not initialize properly. Crash log shows: [FirebaseCore][I-COR000005] No app has been configured yet. Setup details: Unreal Engine: 5.6 (source build, macOS) iOS Deployment: 17.5 MetaHuman character packaged correctly and app launches fine without Firebase Has anyone here managed to get Firebase working inside a native Unreal Engine iOS app with this setup? I'd love to hear if there’s something I’m missing — maybe something with initialization timing or module loading? Thanks so much in advance 🙏

I'm a newbee at Vulkan and Xcode. I have my project on github https://github.com/flocela/OrangeSpider/ Whenever I run, two windows open instead of only one. I added testing, which means I have an OrangeSpider.xctestplan in the OrangeSpider/TestsOrangeSpider/ folder. This is my first time adding testing to an XCode project, so I think this may be where the problem is. I also get this error message: ViewBridge to RemoteViewService Terminated: Error Domain=com.apple.ViewBridge Code=18 "(null)" UserInfo={com.apple.ViewBridge.error.hint=this process disconnected remote view controller -- benign unless unexpected, com.apple.ViewBridge.error.description=NSViewBridgeErrorCanceled}

I notice some metal-cpp classes have static funtion like static URL* fileURLWithPath(const class String* pPath); static class ComputePassDescriptor* computePassDescriptor(); static class AccelerationStructurePassDescriptor* accelerationStructurePassDescriptor(); which return a new object. these classes also provide 'alloc' and 'init' function to create object by default. for object created by 'alloc' and 'init', I use something like NS::Shaderd_Ptr or call release directly to free memory. Because 'alloc' and 'init' not explicit call on these static function. I wonder how to correctly free object created by these static function? did they managed by autorelease pool?