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How to verify with the appropriate signing authority that Apple signed the public key
Hello I trying to implement authentication via apple services in unity game with server made as another unity app On client side I succesfully got teamPlayerID signature salt timestamp publicKeyUrl According to this documentation https://developer.apple.com/documentation/gamekit/gklocalplayer/fetchitems(foridentityverificationsignature:)?language=objc I have to Verify with the appropriate signing authority that Apple signed the public key. As I said my server is special build of unity project So now I have this kind of C# programm to check apple authority over public certificate i got from publicKeyUrl TextAsset textAsset; byte[] bytes; textAsset = Resources.Load<TextAsset>("AppleRootCA-G3"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load<TextAsset>("AppleRootCA-G2"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load<TextAsset>("AppleIncRootCertificate"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); rootCert.Build(cert); Where cert is X509Certificate2 object I ge from publicKeyUrl AppleIncRootCertificate AppleRootCA-G2 AppleRootCA-G3 is certificates I got from https://www.apple.com/certificateauthority/ But it is not work Anytime rootCert.Build(cert); return false Why it is not work? May be I build keychain using wrong root CA cert? Or whole approach incorrect? Please help
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173
Jun ’25
Animations for streaming
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?
0
0
160
May ’25
Unity PolySpatia
Hello, We are experiencing an issue with apparent lag or latency when interacting with objects in Unity using the XR Interaction Toolkit. Even when interactables are configured with the Movement Type set to Instantaneous, objects exhibit a noticeable delay when following hand movement. This issue is particularly apparent when the hand moves at higher speeds. We would like to know: is any additional configuration required, or is there something else we need to do to resolve this? Thank you very much for your assistance.
2
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604
Aug ’25
RealityView content scale factor
Hi, following the recent deprecation of SceneKit, I'm trying to move a couple of my SceneKit projects to RealityKit. One thing I can't seem to find is how to change the content scale factor when using a RealityView in SwiftUI. It was really easy to do in SceneKit with just a SCNView property, and it seems that it's also possible when using ARView, but I can't find a way to do it with a RealityView. Maybe it's a SwiftUI limitation?
3
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238
Jul ’25
iPhone Pro Model - RefreshRate
I want to display the refresh rate on the screen of the iPhone (14 Pro Max), but each app of the App Store's "Floating Clock", "Floating Clock Premium" and "Screen Renewal Rate - RefreshRate Realtime" can only display two of 60Hz and 120Hz, and I wonder if it can display numbers of 1Hz, 10Hz, tens of Hz, or more than 3 levels. Does anyone know how to do it?
1
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334
Sep ’25
Unable to play .aivu with VideoPlayerComponent
I’m trying to play an Apple Immersive video in the .aivu format using VideoPlayerComponent using the official documentation found here: https://developer.apple.com/documentation/RealityKit/VideoPlayerComponent Here is a simplified version of the code I'm running in another application: import SwiftUI import RealityKit import AVFoundation struct ImmersiveView: View { var body: some View { RealityView { content in let player = AVPlayer(url: Bundle.main.url(forResource: "Apple_Immersive_Video_Beach", withExtension: "aivu")!) let videoEntity = Entity() var videoPlayerComponent = VideoPlayerComponent(avPlayer: player) videoPlayerComponent.desiredImmersiveViewingMode = .full videoPlayerComponent.desiredViewingMode = .stereo player.play() videoEntity.components.set(videoPlayerComponent) content.add(videoEntity) } } } Full code is here: https://github.com/tomkrikorian/AIVU-VideoPlayerComponentIssueSample But the video does not play in my project even though the file is correct (It can be played in Apple Immersive Video Utility) and I’m getting this error when the app crashes: App VideoPlayer+Component Caption: onComponentDidUpdate Media Type is invalid Domain=SpatialAudioServicesErrorDomain Code=2020631397 "xpc error" UserInfo={NSLocalizedDescription=xpc error} CA_UISoundClient.cpp:436 Got error -4 attempting to SetIntendedSpatialAudioExperience [0x101257490|InputElement #0|Initialize] Number of channels = 0 in AudioChannelLayout does not match number of channels = 2 in stream format. Video I’m using is the official sample that can be found here but tried several different files shot from my clients and the same error are displayed so the issue is definitely not the files but on the RealityKit side of things: https://developer.apple.com/documentation/immersivemediasupport/authoring-apple-immersive-video Steps to reproduce the issue: - Open AIVUPlayerSample project and run. Look at the logs. All code can be found in ImmersiveView.swift Sample file is included in the project Expected results: If I followed the documentation and samples provided, I should see my video played in full immersive mode inside my ImmersiveSpace. Am i doing something wrong in the code? I'm basically following the documentation here. Feedback ticket: FB19971306
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880
Aug ’25
Unknown CHHapticError.Code (1852797029 == 'nope') in iOS 18+ on iPhone 11 Pro
Hello, I'm getting this error when launching a SpriteKit Swift game in iOS 18+ on an iPhone 11 Pro, whose shell is partly damaged in the back: CHHapticEngine.mm:1206 -[CHHapticEngine doStartWithCompletionHandler:]_block_invoke: ERROR: Player start failed: The operation couldn’t be completed. (com.apple.CoreHaptics error 1852797029.) Haptics do not work on this device, due to the damaged shell, so some error — which obviously occurs when calling start(completionHandler:) — is definitely expected; what is not expected is the main thread sometimes blocking for up to 5 seconds — although the method is not called from the main thread... the error itself is always displayed from some other secondary (system) thread. During this time, the main thread does not access the haptics engine at all; on average, it blocks once every four or five launches. In each launch (blocking or not), the 'nope' error is displayed ~5 seconds after trying to start the engine. After going nuts with all kinds of breakpoints and instrumentation, I'm at a loss as to why the main thread would sometimes block... Ideas, anyone? Thank you, D.
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413
Jul ’25
Unity GameKit Plugin w/ Matchmaking Queue is not working
TLDR; I can't get QueueName to work with matchmaking a turn-based match in Unity using matchmaking rules. Long version: I'm using the apple unity plugin found here: https://github.com/apple/unityplugins/blob/main/plug-ins/Apple.GameKit/Apple.GameKit_Unity/Assets/Apple.GameKit/Documentation~/Apple.GameKit.md I have created a Queue, RuleSet and a simple Rule to match players by following these docs tightly: https://developer.apple.com/documentation/gamekit/finding-players-using-matchmaking-rules. Here is the single rule I have that drives matchmaking: { "data" : { "type" : "gameCenterMatchmakingRules", "id" : "[hiddden-rule-id]", "attributes" : { "referenceName" : "ComplimentaryFactionPreference", "description" : "default desc", "type" : "MATCH", "expression" : "requests[0].properties.preference != requests[1].properties.preference", "weight" : null }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules/[hidden-rule-id]" } }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules" } } which belongs to a rule set which belongs to a queue. I have verified these are setup and linked via the App Store Connect API. Additionally, when I tested queue-based matchmaking without a queue established, I got an error in Unity. Now, with this, I do not. However there is a problem when I attempt to use the queue for matchmaking. I have the basic C# function here: public override void StartSearch(NSMutableDictionary<NSString, NSObject> properties) { if (searching) return; base.StartSearch(properties); //Establish matchmaking requests _matchRequest = GKMatchRequest.Init(); _matchRequest.QueueName = _PreferencesToQueue(GetSerializedPreferences()); _matchRequest.Properties = properties; _matchRequest.MaxPlayers = PLAYERS_COUNT; _matchRequest.MinPlayers = PLAYERS_COUNT; _matchTask = GKTurnBasedMatch.Find(_matchRequest); } The _PreferencesToQueue(GetSerializedPreferences()); returns the exact name of the queue I added my ruleset to. After this function is called, I poll the task generated from the .Find(...) function. Every time I run this function, a new match is created almost instantly. No two players are ever added to the same match. Further, I'm running two built game instances, one on a mac and another on an ipad and when I simultaneously test, I am unable to join games this way. Can someone help me debug why I cannot seem to match make when using a queue based approach?
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1.1k
Sep ’25
Can spatial scene function be used outside of the Photo App?
I'm new here so I don't know what's this function belongs to which topic... Sorry about that! I watched the WWDC stream and I am really interested in this function, I'm wondering if this function could be used in my apps. I looked up the document but I find it only support visionOS(i'm not sure about that, but I saw the demo is base on the visionOS)
2
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316
Jun ’25
Metal HUD Display Value Range
Can't seem to get the Metal HUD to display value range's (pre 26 Tahoe). The documented environment variable MTL_HUD_SHOW_VALUE_RANGE doesn't seem to work. https://developer.apple.com/documentation/xcode/monitoring-your-metal-apps-graphics-performance#Display-the-value-range-of-metrics Anyone having any luck?
2
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359
Sep ’25
How to Configure angularLimitInYZ for PhysicsSphericalJoint in RealityKit (Pendulum/Swing Behavior)
Hello RealityKit developers, I'm currently working on physics simulations in my visionOS app and am trying to adapt the concepts from the official sample Simulating physics joints in your RealityKit app. In the sample, a sphere is connected to the ceiling using a PhysicsRevoluteJoint to create a hinge-like simulation. I've successfully modified this setup to use a PhysicsSphericalJoint instead. The basic replacement works as expected: pin1 (attached to the sphere) rotates freely around pin0 (attached to the ceiling), much like a ball-and-socket joint should, removing all translational degrees of freedom. My challenge lies with the PhysicsSphericalJoint's angularLimitInYZ property. The documentation mentions that this property allows limiting the rotation around the Y and Z axes, defining an "elliptical cone shape around the x-axis of pin0." However, I'm struggling to understand how to specify these values to achieve a desired rotational limit. If I have a sphere that is currently capable of rotating 360 degrees around pin0 (like a free-spinning ball on a string), how would I use angularLimitInYZ to restrict its rotation to a certain height or angular range, preventing it from completing a full circle? Specifically, I'm trying to achieve a "swing" like behavior where the sphere oscillates back and forth but cannot rotate completely overhead or underfoot. What values or approach should I use for the angularLimitInYZ tuple to define such a restricted pendulum-like motion? Any insights, code examples, or explanations on how to properly configure angularLimitInYZ for this kind of behavior would be incredibly helpful! The following code is modified from the sample. extension MainView { func addPinsTo(ballEntity: Entity, attachmentEntity: Entity) throws { let hingeOrientation = simd_quatf(from: [1, 0, 0], to: [0, 0, 1]) let attachmentPin = attachmentEntity.pins.set( named: "attachment_hinge", position: .zero, orientation: hingeOrientation ) let relativeJointLocation = attachmentEntity.position( relativeTo: ballEntity ) let ballPin = ballEntity.pins.set( named: "ball_hinge", position: relativeJointLocation, orientation: hingeOrientation ) // Create a PhysicsSphericalJoint between the two pins. let revoluteJoint = PhysicsSphericalJoint(pin0: attachmentPin, pin1: ballPin) try revoluteJoint.addToSimulation() } } The following image is a screenshot of the operation when changing to PhysicsSphericalJoint. Thank you in advance for your assistance.
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285
Jul ’25
Pink screen on MTLCommandBuffer.presentDrawable.
I rewrote my graphics pipeline to use Load/Store better for clearing and don't care cases. All my tests pass, and in the Metal debugger, all the draw calls succeed. But when I present drawables (before [commandBuffer commit]) I only get a pink screen. I've tried everything I can think of: making sure the pixel formats are the same for the back buffer as my render targets, etc. But it's still pink. Could you point me in the right direction so I can fix this, or help describe why it's pink. That would be really helpful. Thank you, Brian Hapgood
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417
Sep ’25
MacOS Catalina 10.15.7 CoreGraphic.framework not find symbol
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?
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113
May ’25
How to Apple Unity Plugins
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?
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636
Jul ’25
请问Game Center的数据保存逻辑
我们想在游戏类 App 内接入 Game Center。用户可以在游戏内创建多个角色,若用户在游戏内创建了2个角色:角色1、角色2,请问: 当用户将角色1与 Game Center 绑定后,数据将上报至 Game Center。此时玩家想要将角色1与 Game Center 解除绑定,解绑后,再将角色2与 Game Center 绑定。那么这时角色1的数据是留存在 Game Center 中,还是将被移除?
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382
Oct ’25
ProjectiveTransformCameraComponent with custom matrix
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?
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177
Jun ’25
RealityKit Instanced Rendering on visionOS
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
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1.5k
Oct ’25
Struggles with attaching a ModelEntity to the skeleton joints of another ModelEntity
In SceneKit, when creating an .scn file from a rigged model, the framework created an SCNNode for each bone/joint, so you could add and remove child nodes directly to and from joints, and like any other SCNNode, you could access world position and world orientation for each joint. The analog would be for joints to be accessible as child entities of a ModelEntity in RealityKit. I am unable to proceed with migrating my project from SceneKit because of this, as there does not seem to be a way to even access the true world position of a joint with the current jointNames/jointTransforms paradigm. The translation information from the given transforms is insufficient to determine the location of a joint at any given time, and other approaches like creating a GeometricPin for the given joint name and attaching it to another entity do not seem to work. So conveniently being able to attach an item to the hand of a rigged model was trivial in SceneKit and now feels impossible in RealityKit. I am not the first person to notice this, and am feeling demoralized about proceeding with RealityKit with such a critical piece of functionality blocked https://stackoverflow.com/questions/76726241/how-do-i-attach-an-entity-to-a-skeletons-joint-in-realitykit Will this be addressed in some way?
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846
Jul ’25
How to verify with the appropriate signing authority that Apple signed the public key
Hello I trying to implement authentication via apple services in unity game with server made as another unity app On client side I succesfully got teamPlayerID signature salt timestamp publicKeyUrl According to this documentation https://developer.apple.com/documentation/gamekit/gklocalplayer/fetchitems(foridentityverificationsignature:)?language=objc I have to Verify with the appropriate signing authority that Apple signed the public key. As I said my server is special build of unity project So now I have this kind of C# programm to check apple authority over public certificate i got from publicKeyUrl TextAsset textAsset; byte[] bytes; textAsset = Resources.Load&lt;TextAsset&gt;("AppleRootCA-G3"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load&lt;TextAsset&gt;("AppleRootCA-G2"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load&lt;TextAsset&gt;("AppleIncRootCertificate"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); rootCert.Build(cert); Where cert is X509Certificate2 object I ge from publicKeyUrl AppleIncRootCertificate AppleRootCA-G2 AppleRootCA-G3 is certificates I got from https://www.apple.com/certificateauthority/ But it is not work Anytime rootCert.Build(cert); return false Why it is not work? May be I build keychain using wrong root CA cert? Or whole approach incorrect? Please help
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173
Activity
Jun ’25
Issues creating a spatial gallery, how to sync a ImagePresentationComponent size and a SwiftUI overlay ?
Post can be removed.
Replies
2
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0
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271
Activity
Aug ’25
Animations for streaming
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?
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0
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160
Activity
May ’25
Unity PolySpatia
Hello, We are experiencing an issue with apparent lag or latency when interacting with objects in Unity using the XR Interaction Toolkit. Even when interactables are configured with the Movement Type set to Instantaneous, objects exhibit a noticeable delay when following hand movement. This issue is particularly apparent when the hand moves at higher speeds. We would like to know: is any additional configuration required, or is there something else we need to do to resolve this? Thank you very much for your assistance.
Replies
2
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0
Views
604
Activity
Aug ’25
RealityView content scale factor
Hi, following the recent deprecation of SceneKit, I'm trying to move a couple of my SceneKit projects to RealityKit. One thing I can't seem to find is how to change the content scale factor when using a RealityView in SwiftUI. It was really easy to do in SceneKit with just a SCNView property, and it seems that it's also possible when using ARView, but I can't find a way to do it with a RealityView. Maybe it's a SwiftUI limitation?
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3
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238
Activity
Jul ’25
iPhone Pro Model - RefreshRate
I want to display the refresh rate on the screen of the iPhone (14 Pro Max), but each app of the App Store's "Floating Clock", "Floating Clock Premium" and "Screen Renewal Rate - RefreshRate Realtime" can only display two of 60Hz and 120Hz, and I wonder if it can display numbers of 1Hz, 10Hz, tens of Hz, or more than 3 levels. Does anyone know how to do it?
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1
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334
Activity
Sep ’25
Unable to play .aivu with VideoPlayerComponent
I’m trying to play an Apple Immersive video in the .aivu format using VideoPlayerComponent using the official documentation found here: https://developer.apple.com/documentation/RealityKit/VideoPlayerComponent Here is a simplified version of the code I'm running in another application: import SwiftUI import RealityKit import AVFoundation struct ImmersiveView: View { var body: some View { RealityView { content in let player = AVPlayer(url: Bundle.main.url(forResource: "Apple_Immersive_Video_Beach", withExtension: "aivu")!) let videoEntity = Entity() var videoPlayerComponent = VideoPlayerComponent(avPlayer: player) videoPlayerComponent.desiredImmersiveViewingMode = .full videoPlayerComponent.desiredViewingMode = .stereo player.play() videoEntity.components.set(videoPlayerComponent) content.add(videoEntity) } } } Full code is here: https://github.com/tomkrikorian/AIVU-VideoPlayerComponentIssueSample But the video does not play in my project even though the file is correct (It can be played in Apple Immersive Video Utility) and I’m getting this error when the app crashes: App VideoPlayer+Component Caption: onComponentDidUpdate Media Type is invalid Domain=SpatialAudioServicesErrorDomain Code=2020631397 "xpc error" UserInfo={NSLocalizedDescription=xpc error} CA_UISoundClient.cpp:436 Got error -4 attempting to SetIntendedSpatialAudioExperience [0x101257490|InputElement #0|Initialize] Number of channels = 0 in AudioChannelLayout does not match number of channels = 2 in stream format. Video I’m using is the official sample that can be found here but tried several different files shot from my clients and the same error are displayed so the issue is definitely not the files but on the RealityKit side of things: https://developer.apple.com/documentation/immersivemediasupport/authoring-apple-immersive-video Steps to reproduce the issue: - Open AIVUPlayerSample project and run. Look at the logs. All code can be found in ImmersiveView.swift Sample file is included in the project Expected results: If I followed the documentation and samples provided, I should see my video played in full immersive mode inside my ImmersiveSpace. Am i doing something wrong in the code? I'm basically following the documentation here. Feedback ticket: FB19971306
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3
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880
Activity
Aug ’25
Unknown CHHapticError.Code (1852797029 == 'nope') in iOS 18+ on iPhone 11 Pro
Hello, I'm getting this error when launching a SpriteKit Swift game in iOS 18+ on an iPhone 11 Pro, whose shell is partly damaged in the back: CHHapticEngine.mm:1206 -[CHHapticEngine doStartWithCompletionHandler:]_block_invoke: ERROR: Player start failed: The operation couldn’t be completed. (com.apple.CoreHaptics error 1852797029.) Haptics do not work on this device, due to the damaged shell, so some error — which obviously occurs when calling start(completionHandler:) — is definitely expected; what is not expected is the main thread sometimes blocking for up to 5 seconds — although the method is not called from the main thread... the error itself is always displayed from some other secondary (system) thread. During this time, the main thread does not access the haptics engine at all; on average, it blocks once every four or five launches. In each launch (blocking or not), the 'nope' error is displayed ~5 seconds after trying to start the engine. After going nuts with all kinds of breakpoints and instrumentation, I'm at a loss as to why the main thread would sometimes block... Ideas, anyone? Thank you, D.
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2
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413
Activity
Jul ’25
Unity GameKit Plugin w/ Matchmaking Queue is not working
TLDR; I can't get QueueName to work with matchmaking a turn-based match in Unity using matchmaking rules. Long version: I'm using the apple unity plugin found here: https://github.com/apple/unityplugins/blob/main/plug-ins/Apple.GameKit/Apple.GameKit_Unity/Assets/Apple.GameKit/Documentation~/Apple.GameKit.md I have created a Queue, RuleSet and a simple Rule to match players by following these docs tightly: https://developer.apple.com/documentation/gamekit/finding-players-using-matchmaking-rules. Here is the single rule I have that drives matchmaking: { "data" : { "type" : "gameCenterMatchmakingRules", "id" : "[hiddden-rule-id]", "attributes" : { "referenceName" : "ComplimentaryFactionPreference", "description" : "default desc", "type" : "MATCH", "expression" : "requests[0].properties.preference != requests[1].properties.preference", "weight" : null }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules/[hidden-rule-id]" } }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules" } } which belongs to a rule set which belongs to a queue. I have verified these are setup and linked via the App Store Connect API. Additionally, when I tested queue-based matchmaking without a queue established, I got an error in Unity. Now, with this, I do not. However there is a problem when I attempt to use the queue for matchmaking. I have the basic C# function here: public override void StartSearch(NSMutableDictionary<NSString, NSObject> properties) { if (searching) return; base.StartSearch(properties); //Establish matchmaking requests _matchRequest = GKMatchRequest.Init(); _matchRequest.QueueName = _PreferencesToQueue(GetSerializedPreferences()); _matchRequest.Properties = properties; _matchRequest.MaxPlayers = PLAYERS_COUNT; _matchRequest.MinPlayers = PLAYERS_COUNT; _matchTask = GKTurnBasedMatch.Find(_matchRequest); } The _PreferencesToQueue(GetSerializedPreferences()); returns the exact name of the queue I added my ruleset to. After this function is called, I poll the task generated from the .Find(...) function. Every time I run this function, a new match is created almost instantly. No two players are ever added to the same match. Further, I'm running two built game instances, one on a mac and another on an ipad and when I simultaneously test, I am unable to join games this way. Can someone help me debug why I cannot seem to match make when using a queue based approach?
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1
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1.1k
Activity
Sep ’25
Can spatial scene function be used outside of the Photo App?
I'm new here so I don't know what's this function belongs to which topic... Sorry about that! I watched the WWDC stream and I am really interested in this function, I'm wondering if this function could be used in my apps. I looked up the document but I find it only support visionOS(i'm not sure about that, but I saw the demo is base on the visionOS)
Replies
2
Boosts
0
Views
316
Activity
Jun ’25
Metal HUD Display Value Range
Can't seem to get the Metal HUD to display value range's (pre 26 Tahoe). The documented environment variable MTL_HUD_SHOW_VALUE_RANGE doesn't seem to work. https://developer.apple.com/documentation/xcode/monitoring-your-metal-apps-graphics-performance#Display-the-value-range-of-metrics Anyone having any luck?
Replies
2
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0
Views
359
Activity
Sep ’25
How to Configure angularLimitInYZ for PhysicsSphericalJoint in RealityKit (Pendulum/Swing Behavior)
Hello RealityKit developers, I'm currently working on physics simulations in my visionOS app and am trying to adapt the concepts from the official sample Simulating physics joints in your RealityKit app. In the sample, a sphere is connected to the ceiling using a PhysicsRevoluteJoint to create a hinge-like simulation. I've successfully modified this setup to use a PhysicsSphericalJoint instead. The basic replacement works as expected: pin1 (attached to the sphere) rotates freely around pin0 (attached to the ceiling), much like a ball-and-socket joint should, removing all translational degrees of freedom. My challenge lies with the PhysicsSphericalJoint's angularLimitInYZ property. The documentation mentions that this property allows limiting the rotation around the Y and Z axes, defining an "elliptical cone shape around the x-axis of pin0." However, I'm struggling to understand how to specify these values to achieve a desired rotational limit. If I have a sphere that is currently capable of rotating 360 degrees around pin0 (like a free-spinning ball on a string), how would I use angularLimitInYZ to restrict its rotation to a certain height or angular range, preventing it from completing a full circle? Specifically, I'm trying to achieve a "swing" like behavior where the sphere oscillates back and forth but cannot rotate completely overhead or underfoot. What values or approach should I use for the angularLimitInYZ tuple to define such a restricted pendulum-like motion? Any insights, code examples, or explanations on how to properly configure angularLimitInYZ for this kind of behavior would be incredibly helpful! The following code is modified from the sample. extension MainView { func addPinsTo(ballEntity: Entity, attachmentEntity: Entity) throws { let hingeOrientation = simd_quatf(from: [1, 0, 0], to: [0, 0, 1]) let attachmentPin = attachmentEntity.pins.set( named: "attachment_hinge", position: .zero, orientation: hingeOrientation ) let relativeJointLocation = attachmentEntity.position( relativeTo: ballEntity ) let ballPin = ballEntity.pins.set( named: "ball_hinge", position: relativeJointLocation, orientation: hingeOrientation ) // Create a PhysicsSphericalJoint between the two pins. let revoluteJoint = PhysicsSphericalJoint(pin0: attachmentPin, pin1: ballPin) try revoluteJoint.addToSimulation() } } The following image is a screenshot of the operation when changing to PhysicsSphericalJoint. Thank you in advance for your assistance.
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285
Activity
Jul ’25
Pink screen on MTLCommandBuffer.presentDrawable.
I rewrote my graphics pipeline to use Load/Store better for clearing and don't care cases. All my tests pass, and in the Metal debugger, all the draw calls succeed. But when I present drawables (before [commandBuffer commit]) I only get a pink screen. I've tried everything I can think of: making sure the pixel formats are the same for the back buffer as my render targets, etc. But it's still pink. Could you point me in the right direction so I can fix this, or help describe why it's pink. That would be really helpful. Thank you, Brian Hapgood
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2
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417
Activity
Sep ’25
MacOS Catalina 10.15.7 CoreGraphic.framework not find symbol
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?
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113
Activity
May ’25
Cinematic Camera API with ARKit / RealityKit
Hello Apple team, I'm working on an iOS AR app using SwiftUI and RealityKit, and I was wondering if the Cinematic API can be used with a RealityKit scene. I’d like to achieve a shallow depth of field while keeping the 3D asset in focus, and vice versa. Thanks!
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252
Activity
Oct ’25
How to Apple Unity Plugins
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?
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1
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636
Activity
Jul ’25
请问Game Center的数据保存逻辑
我们想在游戏类 App 内接入 Game Center。用户可以在游戏内创建多个角色,若用户在游戏内创建了2个角色:角色1、角色2,请问: 当用户将角色1与 Game Center 绑定后,数据将上报至 Game Center。此时玩家想要将角色1与 Game Center 解除绑定,解绑后,再将角色2与 Game Center 绑定。那么这时角色1的数据是留存在 Game Center 中,还是将被移除?
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382
Activity
Oct ’25
ProjectiveTransformCameraComponent with custom matrix
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?
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177
Activity
Jun ’25
RealityKit Instanced Rendering on visionOS
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
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1.5k
Activity
Oct ’25
Struggles with attaching a ModelEntity to the skeleton joints of another ModelEntity
In SceneKit, when creating an .scn file from a rigged model, the framework created an SCNNode for each bone/joint, so you could add and remove child nodes directly to and from joints, and like any other SCNNode, you could access world position and world orientation for each joint. The analog would be for joints to be accessible as child entities of a ModelEntity in RealityKit. I am unable to proceed with migrating my project from SceneKit because of this, as there does not seem to be a way to even access the true world position of a joint with the current jointNames/jointTransforms paradigm. The translation information from the given transforms is insufficient to determine the location of a joint at any given time, and other approaches like creating a GeometricPin for the given joint name and attaching it to another entity do not seem to work. So conveniently being able to attach an item to the hand of a rigged model was trivial in SceneKit and now feels impossible in RealityKit. I am not the first person to notice this, and am feeling demoralized about proceeding with RealityKit with such a critical piece of functionality blocked https://stackoverflow.com/questions/76726241/how-do-i-attach-an-entity-to-a-skeletons-joint-in-realitykit Will this be addressed in some way?
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846
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Jul ’25