Hello! I need to "draw" a set of particles into the texture. It would be trivial in render encoder of course. However, I would like to implement the task in compute kernel. Every particle draw operation is expected to set 5 texels - "center" one and left/right/upper/lower. Particles can and will overlap, so concurrent draws are to be expected. I tried using texture atomics - atomic_store() to be more precise. This worked, albeit pretty slowly - too slow for my purpose. Just to test what would happen, I tried using normal texture write(). I was expecting to see some kind of visual artefacts, but to my surprise, it worked very well (and much faster). My question: is it safe? I understand that calling write() doesn't guarantee any ordering of the operations, so if multiple threads write to the same texel, the final value may come from any of those threads. But suppose all the threads were to write the very same color? Can I assume that the texel in question will have said color after the compute kernel finishes? I am using M2 Pro MacBook, but ideally I would love to get the answer for the all Apple Silicon devices. My texture format is R32Int (so as to be able to use atomics), but I could do with any single-channel format, the purpose of the texture is to be binary mask of sorts. Thanks!

Hi all, I've developed some code that enables an arcball camera interaction with my scene. I've done this using components and systems. The implementation feels a bit messy as I've got gesture code on my realityView, and then a bunch of other code that uses those gesture inputs in my component and system. Is there a demo app, or some example code that shows a nice way to encapsulate these things in to one item for custom cameras, something like Apple's .realityViewCameraControls(.orbit) If not can anyone recommend an approach to take?

Hi everyone, I'm using the Vision framework’s ImageAestheticsScoresObservation class (https://developer.apple.com/documentation/vision/imageaestheticsscoresobservation). I noticed that the overallScore returned sometimes gives negative values. Could someone confirm whether the expected range of the score is from -1.0 to 1.0? The documentation doesn’t explicitly state the possible score range, so I’d appreciate any clarification or insights. Thanks in advance!

I implemented an EntityAction to change the baseColor tint - and had it working on VisionOS 2.x. import RealityKit import UIKit typealias Float4 = SIMD4<Float> extension UIColor { var float4: Float4 { if cgColor.numberOfComponents == 4, let c = cgColor.components { Float4(Float(c[0]), Float(c[1]), Float(c[2]), Float(c[3])) } else { Float4() } } } struct ColourAction: EntityAction { // MARK: - PUBLIC PROPERTIES let startColour: Float4 let targetColour: Float4 // MARK: - PUBLIC COMPUTED PROPERTIES var animatedValueType: (any AnimatableData.Type)? { Float4.self } // MARK: - INITIATION init(startColour: UIColor, targetColour: UIColor) { self.startColour = startColour.float4 self.targetColour = targetColour.float4 } // MARK: - PUBLIC STATIC FUNCTIONS @MainActor static func registerEntityAction() { ColourAction.subscribe(to: .updated) { event in guard let animationState = event.animationState else { return } let interpolatedColour = event.action.startColour.mixedWith(event.action.targetColour, by: Float(animationState.normalizedTime)) animationState.storeAnimatedValue(interpolatedColour) } } } extension Entity { // MARK: - PUBLIC FUNCTIONS func changeColourTo(_ targetColour: UIColor, duration: Double) { guard let modelComponent = components[ModelComponent.self], let material = modelComponent.materials.first as? PhysicallyBasedMaterial else { return } let colourAction = ColourAction(startColour: material.baseColor.tint, targetColour: targetColour) if let colourAnimation = try? AnimationResource.makeActionAnimation(for: colourAction, duration: duration, bindTarget: .material(0).baseColorTint) { playAnimation(colourAnimation) } } } This doesn't work in VisionOS 26. My current fix is to directly set the material base colour - but this feels like the wrong approach: @MainActor static func registerEntityAction() { ColourAction.subscribe(to: .updated) { event in guard let animationState = event.animationState, let entity = event.targetEntity, let modelComponent = entity.components[ModelComponent.self], var material = modelComponent.materials.first as? PhysicallyBasedMaterial else { return } let interpolatedColour = event.action.startColour.mixedWith(event.action.targetColour, by: Float(animationState.normalizedTime)) material.baseColor.tint = UIColor(interpolatedColour) entity.components[ModelComponent.self]?.materials[0] = material animationState.storeAnimatedValue(interpolatedColour) } } So before I raise this as a bug, was I doing anything wrong in the former version and got lucky? Is there a better approach?

I recently needed to develop an application to obtain the window list, which requires Screen Recording permissions. Apple's official documentation mentions using the two functions CGPreflightScreenCaptureAccess and CGRequestScreenCaptureAccess to request permissions. These functions are stated to be available since version 10.15. However, when I used these two functions on a device running macOS 10.15.7, I encountered the errors shown in the attached screenshot. I used the nm tool to inspect the symbols in the CoreGraphics.framework and found that these two functions were not present. Could you help me understand why this is happening?

Hi, I'm trying to add game center challenges and activities to an already live game, but they are not appearing in game for testing, GameCenter, or the Games app. I know the game is setup with GameKit entitlements since this is a live game and it has working leaderboards and achievements. I've updated to Tahoe beta 8, added a challenge and activity on app store connect, added that to a new distribution and added that distribution to 'Add for Review' I'm using Unity and the Apple Unity plugin Not sure what other steps I'm missing Thanks

So, I'm done with GPTK and decided to delete it. The only thing I installed was brew -v install apple/apple/game-porting-toolkit and the external libraries from the ditto command. Now, I tried to remove it, but even after brew remove game-porting-toolkit brew autoremove all of the dependencies installed with brew are still there. The most obvious was game-porting-toolkit-compiler, but even after removing this there are so many libraries that are now orphaned and it's just impossible to manually identify those. Is there a way or is the easiest way to simply uninstall Homebrew completely and reinstall it again?

I have a visionOS app that I’m adding support for IOS and will like to keep using RealityView. I know there are the following modifiers to add some navigation .realityViewCameraControls(.orbit) .realityViewCameraControls(.dolly) .realityViewCameraControls(.pan) But how can I add more than one? For example I would like to orbit with one finger, Pan with 2 fingers and dolly by pinching. Is this possible and if so can someone share some sample code on how to achieve that? Thanks, Guillermo

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()

Hello! I'm a developer working on a plugin for the Elgato Stream Deck, called GPU Metrics. The plugin currently only works on Windows but I'd like to bring it to macOS. However, based on forum posts I've read (and StackOverflow) there isn't a very clear path to query GPU metrics like usage, temperature, used GPU memory, and power consumption. There are some tools out there that do similar things, but I wanted to see what would be the recommendation from Apple's engineering team to get this data via a public API. Requirements: Access GPU utilization, temperature, memory usage, power usage C/C++ based API for querying the metrics so I can expose the data to JavaScript via Node Addon No need to compatibile with Intel-based Macs, as Apple silicon will be fine for now Plugin GitHub Thank you! Noah

My app has a number of heterogeneous GPU workloads that all run concurrently. Some of these should be executed with the highest priority because the app’s responsiveness depends on them, while others are triggered by file imports and the like which should have a low priority. If this was running on the CPU I’d assign the former User Interactive QoS and the latter Utility QoS. Is there an equivalent to this for GPU work?

I have a game built in Unreal Engine 5.6 which uses tilt motion controls to rotate an object. I've restricted the app to only run in portrait for iPhone, and everything works fine, however for iPad I've had a few issues relating to multitasking and I can't seem to solve it. Forcing the app to portrait only still allows the app to run in landscape mode, but shows black bars either side of the game, and the axes for the motion controls are incorrect. X becomes Y and Y becomes X, and there's no way for my app to know which orientation it is because the container is still technically portrait. Allowing my game to run in all orientations makes the whole app more presentable, it doesn't add black bars and the game is still functional and I'm able to map the controls correctly because the game knows it's landscape rather than portrait. The problem with allowing my app to run in landscape mode is if multitasking is enabled on the ipad, you can resize the app to be portrait, and then I run into the same problem again where the game thinks it's portrait mode and all of the axes are wrong again. I tried getting the true orientation of the device rather than the scene, but the game is intended to be played flat so instead of returning the orientation of the OS the orientation is FaceUp, which doesn't help. I need to either disable multitasking or find a way of getting the orientation of the OS (not the scene or the device). I haven't found how to get the OS orientation so I've been trying to disable multitasking. I've got Requires Fullscreen true and UIApplicationSupportsMultipleScreens false in my info.plist but my iPad still seems to allow the window to be resized in landscape view. Opening the IOS workspace of my project Requires Fullscreen is ticked but under that it says "Supports Multiple Windows" and the arrow button next to it takes my to my info.plist values, but no indication of how I can change it. I'm using Unreal Engine 5.6 and Xcode 16.0. Xcode is old I know, but this version of unreal engine doesn't seem to support any newer.

I'm looking to create an effect on iOS that tracks the user's face position with ARKit and shifts nearer/more prominent geometry in the scene around while more "distant" geometry stays fixed to the XY plane - making it look like the geometry on screen "sticks out" I've managed to implement most of this successfully, but it's not perfect when using PerspectiveCameraComponent in RealityKit because as I shift the camera (and change its field of view based on the user's distance) the backplane changes its orientation (it's always orthogonal to camera's direction). I've tried adopting ProjectiveTransformCameraComponent instead. The idea is that the camera shifts around the scene, mirroring the user's head's position, looking at (0,0,0) and the back plane is adjusted to be parallel with the X,Y plane (animation replicated in Blender below). However, I can't manage to set up ProjectiveTransformCameraComponent with an appropriate matrix or update its transform property in a RealityKit System correctly. I also tried setting many simpler projection matrices as described in a number of guides on camera projection matrices on the internet and all I get is a blank view. Does anyone have some guidance on what the projection matrix that ProjectiveTransformCameraComponent expects is meant to look like or how I would go about accomplishing my goal?

Since macOS 15.3.2, we have observed that when another window is moved near the App Store's install button, the button disappears. We have attached a related video in the Feedback submission here https://feedbackassistant.apple.com/feedback/20444423 Our application overlays a transparent, watermark-window on top of the system window, which causes the install button in the App Store to be hidden when a user attempts to install an application.Could you advise on how to avoid this issue?

We have a macOS app (not yet released, but in use by ourselves), that provides scoreboards for streaming sport events. Today it is expected, that there are nice animations for goals, etc. We are streaming using NDI, which requires a CVPixelBuffer for each frame. We currently create these animations using CABasicAnimation, CAAnimation and CAKeyframeAnimation. In addition we use ScreenCaptureKit to generate the frames. This works fine with 25/30 fps, as long as the window where our animations are performed in is visible. But this is not what it should be. We have a smaller window as main app window and control display performing the animations in reduced size, while the streaming animations need to be in HD format and later maybe in 4K. When using an offscreen window, the animations are not calculated. We get 1 frame per second or so. So we actually have to connect an external display to the MacBook and open the large windows there. Ugly solution. Do we use a completely wrong approach? Or is there a way to tell the macOS to perform the animations although it is an offscreen window? If it cannot work that way, what is an alternative?

hi When analyzing our game using Instruments, I've always been confused about the two items "Drawable Present" and "Drawable Presented" in the GPU column. The timing of Drawable Present seems to be when the CPU layer calls commandbuffer:present, rather than when the actual encoding is completed on the GPU. Also, what does drawable presented specifically mean? In our case, when a CPU stall occurs, it appears that the vsync interval changes in the next frame, and a surface that has already been calculated is not displayed. Why is this happening?

I am trying to use the SVGF denoiser to denoise my ray traced shadows (and also other textures later). I do get a smoothed image, but with wonky denoising. I need the depth-normal textures and motion textures for the SVGF and assume that these are badly filled in my case. However, neither in the above linked documentation nor in the WWDC19 video I find how they should be defined. I am looking to answers to: Is depth in red or alpha channel for the depth-normal texture? Are the normals in screen space? Is depth linear? Is it distance or z coordinate in view space? Or even logarithmically scaled or something else? Are the motion vectors supposed to be in pixels per frame? What is the orientation of the axis? Is y up or down? Are there are other restrictions on the formats? Also the linked code did not help me (I have not found any SVGF so far; also all the code is in Objective-C++, not Swift, but that's a different topic). So how should I fill these textures. Can someone point me to the documentation where these kinds of questions are answered?

iPhone(14 Pro Max)で端末の画面にリフレッシュレートを表示させたいのですが、どなたか方法をご存知ないでしょうか？

I am trying to create an empty metadata, and set the HDRGainMapHeadroom at xxx. However the final returned mutableMetadata doesn't contain the HDRGainMap:HDRGainMapVersion or HDRGainMap:HDRGainMapHeadroom. But iio:hasXMP exist. why? Is that the reason that the namespace HDRGainMap is private? func createHDRGainMapMetadata(version: Int, headroom: Double) -> CGImageMetadata? { // Create a mutable metadata object let mutableMetadata = CGImageMetadataCreateMutable() // Define the namespace for HDRGainMap let namespace = "HDRGainMap" let xmpKeyPath = "iio:hasXMP" let xmpValue = String(true) // Set the HDRGainMapVersion item let versionKeyPath = "\(namespace):HDRGainMapVersion" let versionValue = String(version) // Set the version value let xmpSetResult = CGImageMetadataSetValueWithPath(mutableMetadata, nil, xmpKeyPath as CFString, xmpValue as CFString) if xmpSetResult == false { print("Failed to set xmp") } // Set the version value let versionSetResult = CGImageMetadataSetValueWithPath(mutableMetadata, nil, versionKeyPath as CFString, versionValue as CFString) if versionSetResult == false { print("Failed to set HDRGainMapVersion") } // Set the HDRGainMapHeadroom item let headroomKeyPath = "\(namespace):HDRGainMapHeadroom" let headroomValue = String(headroom) // Set the headroom value let headroomSetResult = CGImageMetadataSetValueWithPath(mutableMetadata, nil, headroomKeyPath as CFString, headroomValue as CFString) if headroomSetResult == false { print("Failed to set HDRGainMapHeadroom") } return mutableMetadata }

Hi, I am working with a large project. We are compiling each material to its own .metallib. They all include many common files full of inline functions. Finally we link it all together at the end with a single big pathtrace kernel. Everything works as expected, however the compile times have gotten completely out of hand and it takes multiple minutes to compile at runtime (to native code). I have gathered that I can do this offline by using metal-tt however if I am wondering if there is a way to reduce the compile times in such a scenario, and how to investigate what the root cause of the problem is. I suspect it could have to do with the fact that every materials metallib contains duplications of all the inline functions. Any ideas on how to profile and debug this? Thanks, Rasmus