I am working on adding synchronized physical properties to EntityEquipment in TableTopKit, allowing seamless coordination during GroupActivities sessions between players.
Treating EntityEquipment's state to DieState is not a way, because it doesn't support custom collision shapes.
I have also tried adding PhysicsBodyComponent and CollisionComponent to EntityEquipment's Entity. However, the main issue is that the position of EntityEquipment itself does not synchronize with the Entity's physics body, resulting in two separate instances of one object.
struct PlayerPawn: EntityEquipment {
let id: ID
let entity: Entity
var initialState: BaseEquipmentState
init(id: ID, entity: Entity) {
self.id = id
let massProperties = PhysicsMassProperties(mass: 1.0)
let material = PhysicsMaterialResource.generate(friction: 0.5, restitution: 0.5)
let shape = ShapeResource.generateBox(size: [0.4, 0.2, 0.2])
let physicsBody = PhysicsBodyComponent(massProperties: massProperties, material: material, mode: .dynamic)
let collisionComponent = CollisionComponent(shapes: [shape])
entity.components.set(physicsBody)
entity.components.set(collisionComponent)
self.entity = entity
initialState = .init(parentID: .tableID, pose: .init(position: .init(), rotation: .zero), entity: self.entity)
}
}
I’d appreciate any guidance on the recommended approach to adding synchronized physical properties to EntityEquipment.
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Hi,
I tried to save the game progress using the official Apple plugin for Unity but the crash happened when I active the "iCloud Documents" inside capabilities and when deactivated it this error message appeared:
Code=27 Domain=GKErrorDomain Description=The requested operation could not be completed because you are not signed in to iCloud or have not enabled iCloud Drive. (UbiquityContainerUnavailable)
Authentication with Game Center works fine using the Core plugin, but nothing works correctly when I use the GameKit plugin.
Note:
I already active iCloud for app Identifier.
Tichnecal informations:
Unity version: 2022.3.47f1 LTS
XCode 16
Swift 6
GameKit-3.0.0 (Apply unity plugin)
Core-3.1.5 (Apply unity plugin)
Ever since the release of iOS18, we've been seeing a new crash related to calling jpegData(compressionQuality:). From reports, this isn't crashing during foreground usage of the app, but instead will prompt the user about a background app crash upon foregrounding. The stacks from crash reports show this crash is happening from a variety of callers, but all go through jpegData(compressionQuality:), down through [HDRImageConverter_Metal init] and end up in apthread_mutex_local call when it crashes.
Attached is a sample crash report from 18.2(22C5125e), but we've been seeing this since the first iOS18 release.
Did something change with around these calls in iOS18 that prohibits their use in the background?
crash.txt
Topic:
Graphics & Games
SubTopic:
Metal
In macOS project with RealityKit and SwiftUI, adding OrthographicCameraComponent causes crashes in both Xcode Preview and at runtime.
import SwiftUI
import RealityKit
struct ContentView: View {
var body: some View {
RealityView { content in
var camera = Entity()
var component = OrthographicCameraComponent()
component.scale = 5
camera.position = [0, 0, 5]
camera.components.set(component)
content.add(camera)
content.add(ModelEntity(mesh: .generateSphere(radius: 1)))
}
}
}
#Preview {
ContentView()
}
Has anyone faced this issue or knows a fix?
I have an oval UIBezierPath with a moving SKSpriteNode,
I stop its motion and record the stopped position. I then restart this motion and want it to restart where it initially stopped.
Works great if motion is not stopped. Movement is great around entire oval Path.
Also works great as long as this stop-restart sequence occurs along the top half of the oval UIBezierPath. However, I have problems along the bottom half of this Path -- it stops okay, but the restart position is not where it previously stopped.
My method to create this oval UIBezierePath is as follows:
func createTrainPath() {
trainRect = CGRect(x: tracksPosX - tracksWidth/2,
y: tracksPosY - tracksHeight/2,
width: tracksWidth,
height: tracksHeight)
// these methods come from @DonMag
trainPoints = generatePoints(inRect: trainRect,
withNumberOfPoints: nbrPathPoints)
trainPath = generatePathFromPoints(trainPoints!,
startingAtIDX: savedTrainIndex)
} // createTrainPath
My method to stop this motion is as follows:
func stopFollowTrainPath() {
guard (myTrain != nil) else { return }
myTrain.isPaused = true
savedTrainPosition = myTrain.position
// also from @DonMag
savedTrainIndex = closestIndexInPath(
trainPath,
toPoint: savedTrainPosition) ?? 0
} // stopFollowTrainPath
Finally, I call this to re-start this motion:
func startFollowTrainPath() {
var trainAction = SKAction.follow(trainPath.cgPath,
asOffset: false,
orientToPath: true,
speed: thisSpeed)
trainAction = SKAction.repeatForever(trainAction)
myTrain.run(trainAction, withKey: runTrainKey)
myTrain.isPaused = false
} // startFollowTrainPath
Again, great if motion is not stopped. Movement is great around entire oval Path.
Again, no problem for stopping and then restarting along top half of oval .. the ohoh occurs along bottom half.
Is there something I need to do within GameScene's update method that I am missing? For example, do I need to reconstruct my UIBezierPath? every time my node moves between the top half and the bottom half and therein account for the fact that the node is traveling in the opposite direction from the top half?
Topic:
Graphics & Games
SubTopic:
SpriteKit
I want to implement the ability to apply Lightroom Preset (.xmp file) to an image in my app, but am running into difficulties. How can I configure things like color grading, curve, etc. in Swift?
Dear Apple Support Team,
I recently purchased an iPad Pro 2022 and updated it to iOS 18.2. However, I am experiencing an issue while using Call of Duty Mobile. The Game Mode activates randomly and sometimes does not activate at all. Additionally, when the Game Mode is on, the game crashes unexpectedly, causing an unstable experience. I kindly request that you address this issue in upcoming iOS updates.
Thank you for your attention and support.
Best regards,
[samadBg]
Topic:
Graphics & Games
SubTopic:
General
I would like to take YCbCr CVPixelBuffers from AVCaptureVideoDataOutput, apply some processing in RGB space, render to an MTKView, and pass to AVAssetWriter for recording.
Right now, I'm doing this all manually – deswing the incoming data if necessary, choose the right matrix to convert to RGB, apply processing, etc. I also have to convert back to YCbCr before feeding the frames to AVAssetWriter because encoding performs much better if I do. Is there any efficient, built-in way to achieve the same?
I can't use AVCaptureVideoPreviewLayer, since I need to do some further processing before display. I can't use AVCaptureVideoDataOutput's videoSettings to get automatic BGRA conversion because that would lose bit depth for 10 bit video formats (and isn't available on all formats anyway).
I see these Accelerate functions, but they seemingly don't use the GPU, nor do they support all the formats and bit depths I'd need.
I found reference to some undocumented MTLPixelFormats that seem to do exactly what I want, but I don't want to rely on something like this unless it's explicitly endorsed. This would also incur an RGB/YCbCr conversion on every texture read and write, right?
Is there anything I'm missing here?
I decided to use a club to kick a ball and let it roll on the turf in RealityKit, but now I can only let it slide but can not roll.
I add collision on the turf(static), club (kinematic) and the ball(dynamic), and set some parameters: radius, mass.
Using these parameters calculate linear damping, inertia, besides, use time between frames and the club position to calculate speed. Code like these:
let radius: Float = 0.025
let mass: Float = 0.04593 // 质量,单位:kg
var inertia = 2/5 * mass * pow(radius, 2)
let currentPosition = entity.position(relativeTo: nil)
let distance = distance(currentPosition, rgfc.lastPosition)
let deltaTime = Float(context.deltaTime)
let speed = distance / deltaTime
let C_d: Float = 0.47 //阻力系数
let linearDamping = 0.5 * 1.2 * pow(speed, 2) * .pi * pow(radius, 2) * C_d //线性阻尼(1.2表示空气密度)
entity.components[PhysicsBodyComponent.self]?.massProperties.inertia = SIMD3<Float>(inertia, inertia, inertia)
entity.components[PhysicsBodyComponent.self]?.linearDamping = linearDamping
// force
let acceleration = speed / deltaTime
let forceDirection = normalize(currentPosition - rgfc.lastPosition)
let forceMultiplier: Float = 1.0
let appliedForce = forceDirection * mass * acceleration * forceMultiplier
entityCollidedWith.addForce(appliedForce, at: rgfc.hitPosition, relativeTo: nil)
Also I try to applyImpulse but not addForce, like:
let linearImpulse = forceDirection * speed * forceMultiplier * mass
No matter how I adjust the friction(static, dynamic) and restitution, using addForce or applyImpulse, the ball can only slide. How can I solve this problem?
I plan to create a simple motion graphics software for macOS that animates text, basic shapes, and handles audio. I'll use SwiftUI for the UI.
What are the commonly used technologies for rendering animated graphics? Core Animation is suitable for UI animations but not for exporting and controlling UI animations.
Basic requirements:
Timeline user interface
Animation of text and basic shapes
Viewer in SwiftUI GUI with transport control (play, pause, scrub, …)
Export to video file
Is Metal or Core Graphics typically used directly? I want to keep it as simple as possible.
I’m trying to build my project using Unreal Engine 5.4 for iOS. I use SocketIO to connect to the backend. The plugin SocketIOClient version 2.8.0, is used for this.
When trying to connect to the socket, a crash occurs. This only happens on iOS, only in Distribution builds, and only on Unreal 5.4. There are no problems on Unreal 5.2. Callstack:
crashlog.crash
The callstack may be slightly different, but the problem is always when allocating or deallocating memory. I suspect that this may be a race condition and is related to some peculiarities of working with memory on iOS. There are also several similar issues in the plugin repository, for example this one.
I tried using other versions of plugin, other versions of xcode, tried to build socket io using both c++20 and c++17, nothing helps. Does anyone know what can be done about this?
Topic:
Graphics & Games
SubTopic:
General
Into a SKScene, I add a SCNSphere as a child of SKShapeNode, as depicted below.
When the sphere hit another node (the fence in the example) the sphere is deformed as it were elastic.
I didn't found any information about elastic properties.
Someone know a way to avoid the deformation?
import SwiftUI
import SpriteKit
import SceneKit
@main struct MyApp: App
{
var body: some Scene
{
WindowGroup {SpriteView(scene: GameSceneSK(size: UIScreen.main.bounds.size))}
}
}
class GameSceneSK: SKScene
{
override func sceneDidLoad() {
var fencePoints = [
CGPoint(x: 300, y: 0), CGPoint(x: 300, y: 400), CGPoint(x: 0, y: 400)
]
let fence = SKShapeNode(points: &fencePoints,
count: fencePoints.count)
fence.physicsBody = SKPhysicsBody(edgeChainFrom: fence.path!)
addChild(fence)
let sphereGeometry = SCNSphere(radius: 20)
let sphereNode = SCNNode(geometry: sphereGeometry)
let sphereScnScene = SCNScene()
sphereScnScene.rootNode.addChildNode(sphereNode)
let ball3D = SK3DNode(viewportSize: CGSize(width: 40,
height: 40))
ball3D.scnScene = sphereScnScene
let ball = SKShapeNode(circleOfRadius: 20)
ball.physicsBody = SKPhysicsBody(circleOfRadius: 20)
ball.addChild(ball3D)
physicsWorld.gravity = CGVector(dx: 0.2, dy: 0.2)
addChild(ball)
}
}
GKGameCenterViewController won't turn off.
With Core and GameKit from GitHub apple/unityplugins,
I succeeded in logging in and displaying GKGameCenterViewController.
Other leaderboards and everything work fine, but when I press X on GameCenter to return to the game, nothing happens.
I tried debugging by printing logs here and there in the plugin to check, but I didn't get any results.
When I press X, I couldn't get any logs or responses. It was like a button with no listener attached. No, it was more like an image.
Based on the community posts that said it worked fine before, it seems that the recent GameCenter update was not applied to the plugin, was omitted, or changed, causing a mismatch.
Hi,
I have a test app with a single "game centre achievement" and I am running it on my iPad and unable to list that achievement with
GameCenterManager.shared.loadAchievements
The app is still in version 1.0, prepare for submission status, (it is not ready for review submission). Game Center entitlement is added for the app and the achievement is added to the Game Center section of app. However it is marked as NotLive.
I am using a sandbox account to login to game centre on the iPad and I can't fetch this achievement. Is it because it is "NotLive". ? How do I test my Game Center achivement on the device without releasing it yet.
Topic:
Graphics & Games
SubTopic:
GameKit
I am using SCNTechnique in combination with ARSCNView.
The technique is doing so minor post-processing. I have written several filter variant for this post-processing, but I'm facing an issue when with one of the filters/fragment shaders, SCNTechnique discards my output and just presents the plain camera feed on screen instead. This is clearly visible in the Metal pipeline, using the GPU frame debugger.
Let me stress that my setup works for 90% of my filters, but not this one and I want to know why.
iOS 18.1, iPhone 13 Mini. Xcode 16.1.
Encoder 0 & 1 are injected by the system.
Render encoder 2 & 3 correspond to my SCNTechnique's render passes: one to manipulate pixel data (darken it in this case) and another to BLIT it back to the main texture. I know the separate buffer is not strictly for this particular operation, but it shouldn't matter.
Note that the issue occurs in encoder 4 (not mine but ARKit's).
In Render Encoder 4, scn_postprocess_AR_fragment handle my texture (#0, ending in f980) and another from the camera feed (Texture 2). I know this pass is typically used for grain because that's what it used to do before I disabled grain on ARSCNView (+ the buffer still contains grain paramaters).
I have other post-processing filters that work just fine. By what magic is ARKit determining to use Texture 2 instead of my Texture 0?
Sure, I could keep digging into the minute differences between my shaders to find out which LoC affects how some ARKit shader down the line operates, but it's awfully opaque so far.
In my SceneKit game I'm able to connect two players with GKMatchmakerViewController. Now I want to support the scenario where one of them disconnects and wants to reconnect. I tried to do this with this code:
nonisolated public func match(_ match: GKMatch, player: GKPlayer, didChange state: GKPlayerConnectionState) {
Task { @MainActor in
switch state {
case .connected:
break
case .disconnected, .unknown:
let matchRequest = GKMatchRequest()
matchRequest.recipients = [player]
do {
try await GKMatchmaker.shared().addPlayers(to: match, matchRequest: matchRequest)
} catch {
}
@unknown default:
break
}
}
}
nonisolated public func player(_ player: GKPlayer, didAccept invite: GKInvite) {
guard let viewController = GKMatchmakerViewController(invite: invite) else {
return
}
viewController.matchmakerDelegate = self
present(viewController)
}
But after presenting the view controller with GKMatchmakerViewController(invite:), nothing else happens. I would expect matchmakerViewController(_:didFind:) to be called, or how would I get an instance of GKMatch?
Here is the code I use to reproduce the issue, and below the reproduction steps.
Code
Run the attached project on an iPad and a Mac simultaneously.
On both devices, tap the ship to connect to GameCenter.
Create an automatched match by tapping the rightmost icon on both devices.
When the two devices are matched, on iPad close the dialog and tap on the ship to disconnect from GameCenter.
Wait some time until the Mac detects the disconnect and automatically sends an invitation to join again.
When the notification arrives on the iPad, tap it, then tap the ship to connect to GameCenter again. The iPad receives the call player(_:didAccept:), but nothing else, so there’s no way to get a GKMatch instance again.
I am working on a SceneKit project where I use a CAShapeLayer as the content for SCNMaterial's diffuse.contents to display a progress bar. Here's my initial code:
func setupProgressWithCAShapeLayer() {
let progressLayer = createProgressLayer()
progressBarPlane?.firstMaterial?.diffuse.contents = progressLayer
DispatchQueue.main.async {
var progress: CGFloat = 0.0
Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { timer in
progress += 0.01
if progress > 1.0 {
progress = 0.0
}
progressLayer.strokeEnd = progress // Update progress
}
}
}
// MARK: - ARSCNViewDelegate
func renderer(_ renderer: SCNSceneRenderer, didAdd node: SCNNode, for anchor: ARAnchor) {
progressBarPlane = SCNPlane(width: 0.2, height: 0.2)
setupProgressWithCAShapeLayer()
let planeNode = SCNNode(geometry: progressBarPlane)
planeNode.position = SCNVector3(x: 0, y: 0.2, z: 0)
node.addChildNode(planeNode)
}
This works fine, and the progress bar updates smoothly. However, when I change the code to use a class property (self.progressLayer) instead of a local variable, the rendering starts flickering on the screen:
func setupProgressWithCAShapeLayer() {
self.progressLayer = createProgressLayer()
progressBarPlane?.firstMaterial?.diffuse.contents = progressLayer
DispatchQueue.main.async { [weak self] in
var progress: CGFloat = 0.0
Timer.scheduledTimer(withTimeInterval: 0.1, repeats: true) { [weak self] timer in
progress += 0.01
if progress > 1.0 {
progress = 0.0
}
self?.progressLayer?.strokeEnd = progress // Update progress
}
}
}
After this change, the progressBarPlane in SceneKit starts flickering while being rendered on the screen.
My Question:
Why does switching from a local variable (progressLayer) to a class property (self.progressLayer) cause the flickering issue in SceneKit rendering?
I'm building a proof of concept application leveraging the PlaneDetectionProvider to generate UI and interactive elements on a horizontal plane the user is looking at. I'm able to create a cube at the centroid of the plane and change it's location via position. However, I can't seem to rotate the cube programmatically and from this forum post in September I'm not sure if the modelEntity.move functionality is still bugged or the documentation is not up to date.
if let planeCentroid = planeEntity.centroid {
// Create a cube at the centroid
let cubeMesh = MeshResource.generateBox(size: 0.1) // Create a cube with side length of 0.1 meters
let cubeMaterial = SimpleMaterial(color: .blue, isMetallic: false)
let cubeEntity = ModelEntity(mesh: cubeMesh, materials: [cubeMaterial])
cubeEntity.position = planeCentroid
cubeEntity.position.y += 0.3048
planeEntity.addChild(cubeEntity)
let rotationY = simd_quatf(angle: Float(45.0 * .pi/180.0), axis: SIMD3(x: 0, y: 1, z: 0))
let cubeTransform = Transform(rotation: rotationY)
cubeEntity.move(to: cubeTransform, relativeTo: planeEntity, duration: 5, timingFunction: .linear)
Ideally, I'd like to have the cube start/stop rotation when the user pinches on the plane mesh but I'd be happy just to see it rotate!
I have a Mac Studio 2023 M2 Max
Running Sonoma 14.6.1
Developing in XCode 16.1
It seems that the NSScreen frame settings may be incorrect. The frame settings received from NSScreen.screens don't seem to match up with the Desktop arrangement settings in the Settings.
Apologies in advance for this long post!
for screen in NSScreen.screens {
let name = screen.localizedName
Globals.logger.debug("Globals initializeScreens - screen \(i) '\(name, privacy: .public)'")
Globals.logger.debug("Globals initializeScreens - '\(screen.debugDescription, privacy: .public)'")
}
This is what I receive in the log:
Globals initializeScreens - '<NSScreen: 0x600000ef4240;
name="PHL 346E2C";
backingScaleFactor=1.000000;
frame={{0, 0}, {3440, 1440}};
visibleFrame={{0, 0}, {3440, 1415}}>'
Globals initializeScreens - screen 2 'Blackmagic (1)'
Globals initializeScreens - '<NSScreen: 0x600000ef42a0;
name="Blackmagic (1)";
backingScaleFactor=1.000000;
frame={{-3840, 0}, {1920, 1080}};
visibleFrame={{-3840, 0}, {1920, 1055}}>'
Globals initializeScreens - screen 3 'Blackmagic (4)'
Globals initializeScreens - '<NSScreen: 0x600000ef4360;
name="Blackmagic (4)";
backingScaleFactor=1.000000;
frame={{-1920, 0}, {1920, 1080}};
visibleFrame={{-1920, 0}, {1920, 1055}}>'
Globals initializeScreens - screen 4 'Blackmagic (2)'
Globals initializeScreens - '<NSScreen: 0x600000ef43c0;
name="Blackmagic (2)";
backingScaleFactor=1.000000;
frame={{5360, 0}, {1920, 1080}};
visibleFrame={{5360, 0}, {1920, 1055}}>'
Globals initializeScreens - screen 5 'Blackmagic (3)'
Globals initializeScreens - '<NSScreen: 0x600000ef4420;
name="Blackmagic (3)";
backingScaleFactor=1.000000;
frame={{3440, 0}, {1920, 1080}};
visibleFrame={{3440, 0}, {1920, 1055}}>'
It looks like the frame settings for Blackmagic (2) and Blackmagic (4) are switched.
The setup has five monitors. Four are using the USB-C Digital AV Multiport Adapters. The output for these are streamed into a rack of A/V equipment using BlackMagic Design mini converters and monitors.
My Swift application allows users to open four movies, one for each of the AV Adapters. The movies can then be played back in sync for later processing by the A/V equipment.
Here are some screen captures that show my display settings.
Blackmagic (1) and Blackmagic (2) are to the left of the main screen.
Blackmagic (3) and Blackmagic(4) are to the right of the main screen.
The desktop is hard to see but is correct.
The wallpaper settings are all correct.
The wallpaper is correctly ordered when displayed on the monitors.
After opening the movies and using the NSScreen frame settings, the displays are incorrectly ordered. Test B and Test D are switched, which is what I would expect given the NSScreen frame values.
Any ideas? I've tried re-arranging the desktops, rebooting, etc. but no luck.
The code that changes the screen location is similar to this post on Stack Overflow
public func setDisplay( screen: NSScreen ) {
Globals.logger.log("MovieWindowController - setDisplay = \(screen.localizedName, privacy: .public)")
Globals.logger.debug("MovieWindowController - setDisplay - '\(screen.debugDescription, privacy: .public)'")
let dx = CGFloat(Constants.midX)
let dy = CGFloat(Constants.midY)
var pos = NSPoint()
pos.x = screen.visibleFrame.midX - dx
pos.y = screen.visibleFrame.midY - dy
Globals.logger.debug("MovieWindowController - setDisplay - x = '\(pos.x, privacy: .public)', y = '\(pos.y, privacy: .public)'")
window?.setFrameOrigin(pos)
}
The log show just what I would expect given the incorrect frame values.
MovieWindowController - setDisplay = Blackmagic (1)
MovieWindowController - setDisplay - '<NSScreen: 0x6000018e8420; name="Blackmagic (1)"; backingScaleFactor=1.000000; frame={{-3840, 0}, {1920, 1080}}; visibleFrame={{-3840, 0}, {1920, 1055}}>'
MovieWindowController - setDisplay - x = '-3840.000000', y = '-12.500000'
MovieWindowController - setDisplay = Blackmagic (2)
MovieWindowController - setDisplay - '<NSScreen: 0x6000018a10e0; name="Blackmagic (2)"; backingScaleFactor=1.000000; frame={{5360, 0}, {1920, 1080}}; visibleFrame={{5360, 0}, {1920, 1055}}>'
MovieWindowController - setDisplay - x = '5360.000000', y = '-12.500000'
MovieWindowController - setDisplay = Blackmagic (3)
MovieWindowController - setDisplay - '<NSScreen: 0x6000018cc8a0; name="Blackmagic (3)"; backingScaleFactor=1.000000; frame={{3440, 0}, {1920, 1080}}; visibleFrame={{3440, 0}, {1920, 1055}}>'
MovieWindowController - setDisplay - x = '3440.000000', y = '-12.500000'
MovieWindowController - setDisplay = Blackmagic (4)
MovieWindowController - setDisplay - '<NSScreen: 0x6000018c9ce0; name="Blackmagic (4)"; backingScaleFactor=1.000000; frame={{-1920, 0}, {1920, 1080}}; visibleFrame={{-1920, 0}, {1920, 1055}}>'
MovieWindowController - setDisplay - x = '-1920.000000', y = '-12.500000'
Am I correct? I think this is driving me crazy!
Thanks in advance!
Edit: The mouse behavior is correct in moving across the displays!
Topic:
Graphics & Games
SubTopic:
General
I want to turn off my ray-tracing conditionally. There's is_null_acceleration_structure but when I don't bind an acceleration structure (or pass nil to setFragmentAccelerationStructure), I get the following API validation error:
-[MTLDebugRenderCommandEncoder validateCommonDrawErrors:]:5782: failed assertion `Draw Errors Validation
Fragment Function(vol_deferred_lighting): missing instanceAccelerationStructure binding at index 6 for accelerationStructure[0].
I can turn off API validation and it works, but it seems like I should be able to use nil for the acceleration structure w/o triggering a validation error. Seems like a bug, right?
I suppose I can work around this by creating a separate pipeline with the ray-tracing disabled via a function constant instead of using is_null_acceleration_structure.
(Can we get a ray-tracing tag for questions?)