Hello, I have noticed a performance drop on SpriteKit-based projects running on iOS 26.0 (23A341). Below is a SpriteKit scene used to test framerate on different devices: import SpriteKit import SwiftUI class BareboneScene: SKScene { override func didMove(to view: SKView) { size = view.bounds.size anchorPoint = CGPoint(x: 0.5, y: 0.5) backgroundColor = .darkGray let roundedSquare = SKShapeNode(rectOf: CGSize(width: 150, height: 75), cornerRadius: 12) roundedSquare.fillColor = .systemRed roundedSquare.strokeColor = .black roundedSquare.lineWidth = 3 addChild(roundedSquare) let action = SKAction.rotate(byAngle: .pi, duration: 1) roundedSquare.run(.repeatForever(action)) } } struct BareboneSceneView: View { var body: some View { SpriteView( scene: BareboneScene(), debugOptions: [.showsFPS] ) .ignoresSafeArea() } } #Preview { BareboneSceneView() } The scene is very simple, yet framerate drops to ~40 fps as shown by the Metal HUD. Tested on: iPhone 13, iOS 26.0: framerate drops to 40 fps. Sometimes it runs at near 60fps. But if the screen is touched repeatedly, the framerate drops to 40-50 fps again. iPhone 11 Pro, iOS 26.0: ~40fps. iPad 9th Gen, iOS 18.6.2: 60fps, no issues. See screenshots attached. These numbers were observed by me and members of our beloved SpriteKit Discord server. Thank you for your attention.

I have a Core Image filter in my app that uses Metal. I cannot compile it because it complains that the executable tool metal is not available, but I have installed it in Xcode. If I go to the "Components" section of Xcode Settings, it shows it as downloaded. And if I run the suggested command, it also shows it as installed. Any advice? Xcode Version Version 26.0 beta (17A5241e) Build Output Showing All Errors Only Build target Lessons of project StudyJapanese with configuration Light RuleScriptExecution /Users/chris/Library/Developer/Xcode/DerivedData/StudyJapanese-glbneyedpsgxhscqueifpekwaofk/Build/Intermediates.noindex/StudyJapanese.build/Light-iphonesimulator/Lessons.build/DerivedSources/OtsuThresholdKernel.ci.air /Users/chris/Code/SerpentiSei/Shared/iOS/CoreImage/OtsuThresholdKernel.ci.metal normal undefined_arch (in target 'Lessons' from project 'StudyJapanese') cd /Users/chris/Code/SerpentiSei/StudyJapanese /bin/sh -c xcrun\ metal\ -w\ -c\ -fcikernel\ \"\$\{INPUT_FILE_PATH\}\"\ -o\ \"\$\{SCRIPT_OUTPUT_FILE_0\}\"' ' error: error: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain /Users/chris/Code/SerpentiSei/StudyJapanese/error:1:1: cannot execute tool 'metal' due to missing Metal Toolchain; use: xcodebuild -downloadComponent MetalToolchain Build failed 6/9/25, 8:31 PM 27.1 seconds Result of xcodebuild -downloadComponent MetalToolchain (after switching Xcode-beta.app with xcode-select) xcodebuild -downloadComponent MetalToolchain Beginning asset download... Downloaded asset to: /System/Library/AssetsV2/com_apple_MobileAsset_MetalToolchain/4d77809b60771042e514cfcf39662c6d1c195f7d.asset/AssetData/Restore/022-19457-035.dmg Done downloading: Metal Toolchain (17A5241c). Screenshots from Xcode Result of "Copy Information" Metal Toolchain 26.0 [com.apple.MobileAsset.MetalToolchain: 17.0 (17A5241c)] (Installed)

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

Hi — we’re testing our app on iOS 26 and ran into strange behavior with GKLocalPlayer.local.authenticateHandler. GKLocalPlayer.local.authenticateHandler = { [weak self] viewController, error in // additional code } What happens: When we assign authenticateHandler on iOS 26 and the user is not signed in to Game Center, the system shows a full-screen Game Center overlay asking the user to sign in. If the user taps Cancel, nothing further happens — the closure is not invoked again, so we don’t receive an error or any callback. The app never learns whether the auth was cancelled or failed. In previous iOS versions the closure was called (with viewController / error as appropriate) and the flow worked as expected. What we tried: Verified authenticateHandler is being set. Checked GKLocalPlayer.local.isAuthenticated after the overlay dismisses — it’s unchanged. Observed system logs: a com.apple.GameOverlayUI scene is created and later removed (so the auth overlay is shown by the system). Confirmed the same code works on earlier iOS versions. :thinking: Question: Has anyone seen authenticateHandler not being invoked on iOS 26 when the Game Center auth overlay is presented? Could this be a behavioral change in iOS 26 (overlay runs in a separate system process), or a bug? Any suggested workarounds to reliably detect that the user cancelled the sign-in (for example: listening for willResignActive / didBecomeActive, watching for a system overlay, or saving/presenting the viewController manually)? Thanks in advance for any advice — we’d appreciate pointers or suggested diagnostics ?

Hello, Im trying to install it following these steps https://www.applegamingwiki.com/wiki/Game_Porting_Toolkit but i get an error with 'brew install apple/apple/game-porting-toolkit' ==> tar -xf crossover-sources-22.1.1.tar.gz --include=sources/clang/* --strip-components=2 ==> cmake -G Ninja -DCMAKE_VERBOSE_MAKEFILE=Off -DCMAKE_MAKE_PROGRAM=ninja -DCMAKE_VERBOSE_MAKEFILE=On -DCMAKE_OSX_ARCHITECTUR Last 15 lines from /Users/rafael/Library/Logs/Homebrew/game-porting-toolkit-compiler/02.cmake: -DLLVM_INSTALL_TOOLCHAIN_ONLY=On -DLLVM_ENABLE_PROJECTS=clang /private/tmp/game-porting-toolkit-compiler-20250519-44600-qwrjgl/llvm CMake Error at CMakeLists.txt:3 (cmake_minimum_required): Compatibility with CMake < 3.5 has been removed from CMake. Update the VERSION argument <min> value. Or, use the <min>...<max> syntax to tell CMake that the project requires at least <min> but has been updated to work with policies introduced by <max> or earlier. Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway. -- Configuring incomplete, errors occurred! If reporting this issue please do so to (not Homebrew/* repositories): apple/apple MacOS 15.3.1 Thank you in advanced Regards

Hi, developers, I maintain a shipped app that uses string concatenation to construct Metal shader and compile on-device. Beta 4 seems disabled __asm keyword, resulting the compilation failure. The error is: v2/GEMMKernel.cpp:229: error: program_source:23:9: error: illegal string literal in 'asm' __asm("air.simdgroup_async_copy_1d.p3i8.p1i8"); The relevant code is available at https://github.com/liuliu/ccv/blob/unstable/lib/nnc/mfa/v2/GEMMHeaders.cpp#L30 although any __asm will trip this. Please give us guidance on whether this is a regression or this will be something enforced in 26 release. Personally, I would consider this as a bug given it won't impact anything "compiled" shaders. Thanks for your patience reading this!

I've had no issue calling image files in my .swift files, but they are causing crashes when used in my .SKS files. When I set a sprite texture to an image in the inspector/ editor bar, at runtime when that sprite is being called I get the error: "Cannot get value with size 16. The type encoded as {CGRect={CGPoint=dd}{CGSize=dd}} is expected to be 32 bytes." From my research it has something to do with Apple switching from 32 to 64 bite machines. From chatGPT “SpriteKit under the hood uses NSKeyedUnarchiver to load your .sks file. That unarchiver decodes each archived property by reading a fixed‑size blob of bytes and mapping it into a C struct. In your case it ran into a mismatch”. I am using a 64-bite machine to write my code and 64-bite simulators and physical devices, so there isn't a clear cause of the mismatch. My scenes play fine in Xcode 16's preview window and my code builds, it just crashes at runtime. When I don’t use image textured assets in the SKS file it works fine. It loads animated labels, and plain color squares. I’ve been able to work around this for static things like a sprite with a background texture by. in a normal non-game swift file, writing code like: if let scene = SKScene(fileNamed: "GameScene2") { let bg = SKSpriteNode(imageNamed: "YourBackgroundImage") bg.position = CGPoint(x: scene.frame.midX, y: scene.frame.midY) bg.zPosition = -1 scene.addChild(bg) } The issue now is I want to make a particle emitter and other non static sprites, but my understanding of their properities isn’t deep enough to create them without the editor. Also when I set SKTexture in a swift file that causes the same runtime crash with the 16/32 error. Could you help me figure out how to fix the bug so I can use the editor again? Otherwise could you help me figure out how to write a workaround like I do for background images? I have a feeling the answer is in writing my own NSKeyedUnarchiver but I don’t know how to make sure it’s called instead of the default one. I've already tried cleaning my code multiple times and deleting and reading sprite nodes. Thank you.

Any body have the link to the sample code for the “Bring your SceneKit project to RealityKit” session. I can’t see it any where in the Dev sample code pages

We are seeing crashes in Xcode organizer. So far we are not able to reproduce them locally. They affect multiple app releases (some older, built with Xcode 15.x and newer built with Xcode 16.0). They only affect iOS 18.5. Is there anything that changed in latest iOS? It's hard to tell what exactly is causing this crash because setting symbolic breakpoint on CA::Render::Image::new_image(unsigned int, unsigned int, unsigned int, unsigned int, CGColorSpace*, void const*, unsigned long const*, void (*)(void const*, void*), void*) triggers this breakpoint all the time, but not necessarily with exactly the previous stack frames matching the crash report. Is it a known issue? crash.crash Thank you.

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

I have published a number of games that use SpriteKit for everything important. Since the release of macOS Tahoe, I've had a lot of end user reports saying that sound effects have stopped working in many (but not all) of my titles. I'm not doing anything unusual here – typical code is: sndGameOver = [SKAction playSoundFileNamed:@"Audio/GameOver.wav" waitForCompletion:YES]; Then at the appropriate time: [self runAction:sndGameOver]; Has anyone else encountered this? The code still works fine on previous operating systems, and appears to be fine on iOS too. Has something changed in macOS Tahoe? I'm at a bit of a loss. There's nothing obviously different between the titles that do work and the titles that don't. Suggestions welcomed! Thanks

It's a Broadcast Extension issue: on iOS 26.1 beta the extension never launches—after you tap “Start Broadcast” in the system picker the countdown disappears after 3 s and no broadcast starts, so every live-streaming app（and all other non-system apps that use Broadcast Extension） fails to go live (only the native Photos screen recording still works). Is this a known regression or is a new entitlement required?

[CRITICAL] Metal API Memory Leak - Heap Memory Never Released to OS (CWE-400) Security Classification This issue constitutes a resource exhaustion vulnerability (CWE-400): Aspect Details Type Uncontrolled Resource Consumption CWE CWE-400 Vector Local (any Metal application) Impact System instability, denial of service User Control None - no mitigation available Recovery Requires application restart Summary Metal heap allocations are never released back to macOS, even when the memory is entirely unused. This causes continuous, unbounded memory growth until system instability or crash. The issue affects any application using Metal API heap allocation. This was discovered in Unreal Engine 5, but reproduces in a completely blank UE5 project with zero application code - confirming this is Metal framework behavior, not application-level. Environment OS: macOS Tahoe 26.2 Hardware: Apple Silicon M4 Max (also reproduced on M1, M2, M3) API: Metal Reproduction Steps Run any Metal application that allocates and deallocates GPU buffers via Metal heaps Open Activity Monitor and observe the application's memory usage Let the application run idle (no user interaction required) Observe memory growing continuously at ~1-2 MB per second Memory never plateaus or stabilizes Eventually system becomes unstable For testing: Any Unreal Engine 5.4+ project on macOS will reproduce this. Even a blank project with no gameplay code exhibits the leak. (Tested on UE 5.7.1) Observed Behavior Memory Analysis Using Unreal's memreport -full command, two reports taken 86 seconds apart: Metric Report 1 (183s) Report 2 (269s) Delta Process Physical 4373.64 MB 4463.39 MB +89.75 MB Metal Heap Buffer 7168 MB 8192 MB +1024 MB Unused Heap 3453 MB 4477 MB +1024 MB Object Count 73,840 73,840 0 (no change) Key Finding Metal Heap grew by exactly 1 GB while "Unused Heap" also grew by 1 GB. This demonstrates: Metal is allocating new heap blocks in ~1 GB increments Previously allocated heap memory becomes "unused" but is never released The unused memory accumulates indefinitely No application-level objects are leaking (count remains constant) Memory Growth Pattern Continuous growth while idle (no user interaction) Growth rate: approximately 1-2 MB per second No plateau or stabilization occurs Metal allocates new 1 GB heap blocks rather than reusing freed space Eventually leads to system instability and crash What is NOT Causing This We verified the following are NOT the source: Application objects - Object count remains constant Application code - Blank project with no code reproduces the issue Texture streaming - Disabling texture streaming had no effect CPU garbage collection - Running GC has no effect (this is GPU memory) Mitigations Attempted (None Worked) setPurgeableState Setting resources to purgeable state before release: [buffer setPurgeableState:MTLPurgeableStateEmpty]; Result: Metal ignores this hint and does not reclaim heap memory. Avoiding Heap Pooling Forcing individual buffer allocations instead of heap-based pooling. Result: Leak persists - Metal still manages underlying allocations. Aggressive Buffer Compaction Attempting to compact/defragment buffers within heaps every frame. Result: Only moves data between existing heaps. Does NOT release heaps back to OS. Reducing Pool Sizes Minimizing all buffer pool sizes to force more frequent reuse. Result: Slightly slows the leak rate but does not stop it. Root Cause Analysis How Metal Heap Allocation Appears to Work Metal allocates GPU heap blocks in large chunks (~1 GB observed) Application requests buffers from these heaps When application releases buffers, memory becomes "unused" within the heap Metal does NOT release heap blocks back to macOS, even when entirely unused When fragmentation prevents reuse, Metal allocates new heap blocks Result: Continuous memory growth with no upper bound The Core Problem There appears to be no Metal API to force heap memory release. The only way to reclaim this memory is to destroy the Metal device entirely, which requires restarting the application. Expected Behavior Metal should: Release unused heaps - When a heap block is entirely unused, release it back to macOS Respect purgeable hints - Honor setPurgeableState calls from applications Compact allocations - Defragment heap allocations to reduce fragmentation Provide control APIs - Allow applications to request heap compaction or release Enforce limits - Have configurable maximum heap memory consumption Security Implications Local Denial of Service - Any Metal application can exhaust system memory, causing instability affecting all running applications Memory Pressure Attack - Forces other applications to swap to disk, degrading system-wide performance No Upper Bound - Memory consumption continues until system failure Unmitigable - End users have no way to prevent or limit the leak Affects All Metal Apps - Any application using Metal heaps is potentially affected Impact Applications become unstable after extended use System-wide performance degrades as memory pressure increases Users must periodically restart applications Developers cannot work around this at the application level Long-running applications (games, creative tools, servers) are particularly affected Request Investigate Metal heap memory management behavior Implement heap release when blocks become entirely unused Honor setPurgeableState hints from applications Consider providing an API for applications to request heap compaction Document any intended behavior or workarounds Additional Notes This issue has been observed across multiple Unreal Engine versions (5.4, 5.7) and multiple Apple Silicon generations (M1 through M4). The behavior is consistent and reproducible. The Unreal Engine team has implemented various CVars to attempt mitigation (rhi.Metal.HeapBufferBytesToCompact, rhi.Metal.ResourcePurgeInPool, etc.) but none successfully address the issue because the root cause is at the Metal framework level. Tested: January 2026 Platform: macOS Tahoe 26.2, Apple Silicon (M1/M2/M3/M4)

Can I use them in SK and do the animations work? Thanks, Patrick

I'm an experienced SceneKit developer and I want to begin work on a new project using RealityKit. So I appreciated as timely, the WWDC 2025 Session, "Bring your SceneKit project to RealityKit". However, now I am finding that: Blender does not properly support exporting armatures in usdc files, and usdc is really the only file format that should be used for creating 3D assets for RealityKit. The option of exporting from Blender to fbx or some other intermediate format, and then converting that to usdc, is a challenge. Apple's Reality Converter App, which supposedly can support importing and converting fbx files to usdc, is no longer available from Apple's website. And an older copy of it I found at the Kodeco website requires Rosetta on Apple Silicon. As well, this older copy does not in fact import fbx or anything else - I find it doesn't work at all. Apple's Reality Composer Pro, at least as far as I can tell, only supports importing usdc - it is not a file conversion tool. Alternatively, I am under the impression that Maya supports producing usdc files with armatures, but Maya costs over $2000 per year and I am skilled with Blender, so I believe strongly that I should be able to continue with Blender. Maya's expense and skillset simply shouldn't be a requirement for building RealityKit applications. What are my options then, if any, to produce assets with armatures and armature based animations using Blender, and then bring them into RealityKit?

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.

When previewing the recording of gameplay the buttons to exit or save are unclickable behind the top bar clock and Wi-Fi/5G status bar. Which means that you have to quit the game in order to continue. Tested on multiple devices. Does anyone have a solution to this? At the moment we have disabled it altogether for iOS 26 users.

Is there any standard way of efficiently showing a MTLTexture on a RealityKit Entity? I can't find anything proper on how to , for example, generate a LowLevelTexture out of a MTLTexture. Closest match was this two year old thread. In the old SceneKit app, we would just do guard let material = someNode.geometry?.materials.first else { return } material.diffuse.contents = mtlTexture Our flow is as follows (for visualizing the currently detected object): Camera-Stream -> CoreML Segmentation -> Send the relevant part of the MLShapedArray-Tensor to a MTLComputeShader that returns a MTLTexture -> Show the resulting texture on a 3D object to the user

Hi everyone, I'm developing an ARKit app using RealityKit and encountering an issue where a video displayed on a 3D plane shows up as a pink screen instead of the actual video content. Here's a simplified version of my setup: func createVideoScreen(video: AVPlayerItem, canvasWidth: Float, canvasHeight: Float, aspectRatio: Float, fitsWidth: Bool = true) -> ModelEntity { let width = (fitsWidth) ? canvasWidth : canvasHeight * aspectRatio let height = (fitsWidth) ? canvasWidth * (1/aspectRatio) : canvasHeight let screenPlane = MeshResource.generatePlane(width: width, depth: height) let videoMaterial: Material = createVideoMaterial(videoItem: video) let videoScreenModel = ModelEntity(mesh: screenPlane, materials: [videoMaterial]) return videoScreenModel } func createVideoMaterial(videoItem: AVPlayerItem) -> VideoMaterial { let player = AVPlayer(playerItem: videoItem) let videoMaterial = VideoMaterial(avPlayer: player) player.play() return videoMaterial } Despite following the standard process, the video plane renders pink. Has anyone encountered this before, or does anyone know what might be causing it? Thanks in advance!

So I've been trying out GPTK with Elite Dangerous Horizons game and it looks like from what I can tell. The VRAM keeps going up until it goes over the limit where it drops the FPS to 1-3 FPS and then crashes the game. From the Performance HUD I can see that it looks like when using GPTK, the VRAM usage just keeps climbing and I never saw it drop down at all. I did some limited testing, and from that I think I can conclude that it is probably not a VRAM leak, but it might be caching it. The reason for this is because I noticed that if I went back to the area that I've been before. It won't increase the VRAM usage. So either there is something wrong with the freeing VRAM memory part, or it could be that GPTK might not be reporting the right amount of VRAM available to use? So maybe that's why it keeps allocating VRAM until it went out of memory and crashed the game. Just to test, I did try running the game with DXVK+MoltenVK combo, and I can see that it works just fine. VRAM is being freed up when it's no longer used. Is this a known issue in some games?