This is my code in ContentView: import SwiftUI import SceneKit import PlaygroundSupport struct ContentView: View { var body: some View { VStack { Text("SceneKit with SwiftUI") .font(.headline) .padding() SceneView( scene: loadScene(), options: [.autoenablesDefaultLighting, .allowsCameraControl] ) .frame(width: 400, height: 400) .border(Color.gray, width: 1) } } } func loadScene() -> SCNScene? { if let fileURL = Bundle.main.url(forResource: "a", withExtension: "dae") { do { let scene = try SCNScene(url: fileURL, options: [ SCNSceneSource.LoadingOption.checkConsistency: true ]) print("Scene loaded successfully.") return scene } catch { print("Error loading scene: \(error.localizedDescription)") } } else { print("Error: Unable to locate a.dae in Resources.") } return nil } a.dae file exists in the Resources section of macOS Playground app. And a.dae can be viewed in Xcode. Console shows: Error loading scene: The operation couldn’t be completed. (Foundation._GenericObjCError error 0.) Any input is appreciated.

Up to now I have created multiple new SCNNodes using an instance of SCNGeometry and it was OK that they all had the same appearance. Now I want variety and when I make a copy of that instance using: let newGeo = myGeoInstance.copy() as! SCNGeometry (must be force cast because copy() -> any?) all elements are verified present. :-) Likewise: node.geometry?.replaceMaterial(at: index, with: myNewMaterial) is verified to correctly change the material(s) at the correct index(s). The only problem is the modified "teapot" is not visible, and yes I have set node.isHidden = false. Has anyone experienced this? In the old days reversing the verts was a solution. In desperation I tried that. |-(

The Actions Editor doesn't seem to work in Xcode 16.1. With a node selected, when I try to drag an action from the Library into the Actions panel nothing happens, the action icon just disappears. Clicking the '+' button to create a new action doesn't work either. Actions do work when created in code, though. Is this a bug, or am I missing something?

I would like to implement zoom functionality in my SceneKit game: when the user performs the pinch gesture on a point on the screen, the scene zooms in to make that point larger. Until now I simply changed SCNCamera.focalLength, but this simply zooms in to the center of what is currently visible on screen. Is it somehow possible to implement the zoom functionality described above by perhaps interactively rotating the camera at the same time towards the pinched point? Is there a formula for this? I would like to avoid suddenly rotating the camera to face the pinched point when the pinch gesture begins and then zoom in while the pinch is in progress.

I am trying to extract some built-in and custom render passes from SceneKit, so that I can pass them into a metal pipeline and do some additional work with them. I have a metal viewport, and have instantiated a SCNRenderer so that I can render a SCNScene using SceneKit to a texture as part of my metal draw pass. This works as expected. Now I want to output multiple textures from the SceneKit render, not just the final color. I want to extract Depth, Normal, Lighting, Colour and a custom SCNTechnique for world position. I can easily use a SCNTechnique to render one of these to the color output, but it's not clear how I would render multiple passes in one render call. Is there some way to pass a writeable buffer/texture to a SCNTechnique, so that I can populate it in my SCNTechnique shader at render time with the output from the pass? Similar to how one would bind a buffer for a metal shader. SCNTechnique obfuscates things, so it's not clear how to proceed. Does anyone have any ideas?

When running the sample code below, every 3 seconds the middle sprite is replaced by a new one. When this happens, most of the time a flicker is noticeable. When recording the screen and stepping through the recording frame by frame, I noticed that the flicker is caused by a temporary reordering of the nodes’. Below you find two screenshots of two consecutive frames where the reordering is clearly visible. This only happens for a SpriteKit scene used as an overlay for a SceneKit scene. Commenting out buttons.zPosition = 1 or avoiding the fade in/out animations solves the issue. I have created FB15945016. import SceneKit import SpriteKit class GameViewController: NSViewController { let overlay = SKScene() var buttons: SKNode! var previousButton: SKSpriteNode! var nextButton: SKSpriteNode! var pageContainer: SKNode! var pageViews = [SKNode]() var page = 0 override func viewDidLoad() { super.viewDidLoad() let scene = SCNScene(named: "art.scnassets/ship.scn")! let scnView = self.view as! SCNView scnView.scene = scene overlay.anchorPoint = CGPoint(x: 0.5, y: 0.5) scnView.overlaySKScene = overlay buttons = SKNode() buttons.zPosition = 1 overlay.addChild(buttons) previousButton = SKSpriteNode(systemImage: "arrow.uturn.backward.circle") previousButton.position = CGPoint(x: -100, y: 0) buttons.addChild(previousButton) nextButton = SKSpriteNode(systemImage: "arrow.uturn.forward.circle") nextButton.position = CGPoint(x: 100, y: 0) buttons.addChild(nextButton) pageContainer = SKNode() pageViews = [SKSpriteNode(systemImage: "square.and.arrow.up"), SKSpriteNode(systemImage: "eraser")] overlay.addChild(pageContainer) setPage(0) Timer.scheduledTimer(withTimeInterval: 3, repeats: true) { [self] _ in setPage((page + 1) % 2) } } func setPage(_ page: Int) { pageViews[self.page].run(.sequence([ .fadeOut(withDuration: 0.2), .removeFromParent() ]), withKey: "fade") self.page = page let pageView = pageViews[page] pageView.alpha = 0 pageView.run(.fadeIn(withDuration: 0.2), withKey: "fade") pageContainer.addChild(pageView) } override func viewDidLayout() { overlay.size = view.frame.size } } extension SKSpriteNode { public convenience init(systemImage: String) { self.init() let width = 100.0 let image = NSImage(systemSymbolName: systemImage, accessibilityDescription: nil)!.withSymbolConfiguration(.init(hierarchicalColor: NSColor.black))! let scale = NSScreen.main!.backingScaleFactor image.size = CGSize(width: width * scale, height: width / image.size.width * image.size.height * scale) texture = SKTexture(image: image) size = CGSize(width: width, height: width / image.size.width * image.size.height) } }

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 want to apply a SCNTechnique pipeline to the camera feed. To achieve this, I want to bring the camera input into the SceneKit world. The perfects API seems to be: let captureDevice = … scnScene.background.contents = captureDevice This is demonstrated in "SceneKit: What's New" (WWDC17) (at 44m19s) and is mentioned in the documentation of SCNMaterialProperty's contents. Instead of showing camera feed, it crashes with these messages: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[AVCaptureVideoDataOutput setVideoSettings:] Unsupported pixel format type - use -availableVideoCVPixelFormatTypes' *** First throw call stack: (0x18993c7cc <REDACTED> 0x211e18488) libc++abi: terminating due to uncaught exception of type NSException Please advise. STEPS TO REPRODUCE Create a new Xcode project, starting from the SceneKit game template. Add Info.plist entry for NSCameraUsageDescription. Add a capture device property to GameViewController: class GameViewController: UIViewController { let captureDevice = AVCaptureDevice.default(for: .video) Set the background contents: scene.background.contents = captureDevice Run the app on device. PLATFORM AND VERSION iOS Development environment: Xcode 16.1, macOS 15.0.1. Run-time configuration: iOS 18.1

I would like to preload and use some images for both SpriteKit and SceneKit models (my game uses SceneKit with a SpriteKit overlay), and as far as I can see the only efficient way would be to create and preload SKTexture objects which can be supplied to SKSpriteNode(texture:) and SCNMaterial.diffuse.contents. The problem is that SKTexture are rendered too bright in SceneKit, for some unknown reason. Here a comparison between rendering an image (from URL) and a SKTexture: And the code that produces it: let url = Bundle.main.url(forResource: "art.scnassets/texture.png", withExtension: nil)! let plane1 = SCNPlane(width: 10, height: 10) plane1.firstMaterial!.diffuse.contents = url.path let node1 = SCNNode(geometry: plane1) node1.position.x = -5 scene.rootNode.addChildNode(node1) let plane2 = SCNPlane(width: 10, height: 10) plane2.firstMaterial!.diffuse.contents = SKTexture(image: NSImage(byReferencing: url)) let node2 = SCNNode(geometry: plane2) node2.position.x = 5 scene.rootNode.addChildNode(node2) This issue was already mentioned in this other post, but since I wasn't notified of the reply from Quinn asking about the feedback number I created at the time, it didn't make any progress.

I've been running my SceneKit game for many weeks in Xcode without performance issues. The game itself is finished, so I thought I could go on with publishing it on the App Store, but when archiving it in Xcode and running the archived app, I noticed that it seriously hangs. The hangs only seem to happen when I run the game in fullscreen mode. I tried disabling game mode, but the hangs still happen. Only when I run in windowed mode the game runs smoothly. Instruments confirms that there are many serious hangs, but it also reports that CPU usage is quite low during those hangs, on average about 15%. From what I know, hangs happen when the main thread is busy, but how can that be when CPU usage is so low, and why does it only happen in fullscreen mode for release builds?

In the simplest case I can come up with, I create a scene (either fully or partially in code) with a single dynamic body, located slightly away from the origin. I give the body a charge as well as adding an electric field to the node. Body does nothing (as to be expected, since it's the source of the field). However if I replace that field with a custom field (does nothing except reports back the passed in position value) the position shown is the location of the body in the local space of its parent (in this case, the root node) rather than the node the field is attached to (i.e. itself). I've attached the code customising the SwiftUI app template. Hopefully someone can tell me what I'm doing wrong? ContentView customisation… struct ContentView: View { var body: some View { SceneView(scene: ElectricScene(), options: [.allowsCameraControl, .autoenablesDefaultLighting]) } } And the code to create the scene… import Foundation import SceneKit class ElectricScene: SCNScene { override init() { super.init() physicsWorld.gravity = SCNVector3(0, 0, 0) let cameraNode = SCNNode() cameraNode.camera = SCNCamera() cameraNode.position = SCNVector3(0, 0, 10) rootNode.addChildNode(cameraNode) let ballNode = SCNNode(geometry: SCNSphere(radius: 0.5)) ballNode.position = SCNVector3(2, 0, 0) ballNode.physicsBody = SCNPhysicsBody(type: .dynamic, shape: nil) ballNode.physicsBody?.charge = -1 rootNode.addChildNode(ballNode) // ballNode.physicsField = SCNPhysicsField.electric() ballNode.physicsField = SCNPhysicsField .customField {position, _, _, _, _ in print(position) return SCNVector3Zero } } @available(*, unavailable) required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } } This (repeatedly) prints out the following… SCNVector3(x: 2.0, y: 0.0, z: 0.0) …which is the position of the node relative to the root node, rather than relative to the source of the field (itself).

Even when the action is run on the main thread, the following code causes a crash on iOS, but not on macOS. The game launches with a simple yellow rectangle, and when it finishes fading out and should be removed from the overlay scene, the app crashes. The code can be pasted into the file GameController.swift of Xcode's default project for Multiplatform macOS and iOS game. import SceneKit import SpriteKit @MainActor class GameController: NSObject { let scene: SCNScene let sceneRenderer: SCNSceneRenderer init(sceneRenderer renderer: SCNSceneRenderer) { sceneRenderer = renderer scene = SCNScene(named: "Art.scnassets/ship.scn")! super.init() sceneRenderer.scene = scene renderer.overlaySKScene = SKScene(size: CGSize(width: 500, height: 500)) DispatchQueue.main.async { let node = SKShapeNode(rect: CGRect(x: 100, y: 100, width: 100, height: 100)) node.fillColor = .yellow node.run(.sequence([ .fadeOut(withDuration: 1), .removeFromParent() ])) renderer.overlaySKScene!.addChild(node) } } } The Xcode console shows this stacktrace: *** Assertion failure in -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:], UIApplication.m:3246 *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Call must be made on main thread' *** First throw call stack: ( 0 CoreFoundation 0x00000001804ae0f8 __exceptionPreprocess + 172 1 libobjc.A.dylib 0x0000000180087db4 objc_exception_throw + 56 2 Foundation 0x0000000180d17058 _userInfoForFileAndLine + 0 3 UIKitCore 0x00000001853cf678 -[UIApplication _performAfterCATransactionCommitsWithLegacyRunloopObserverBasedTiming:block:] + 376 4 UIKitCore 0x000000018553f7a0 -[_UIFocusUpdateThrottle scheduleProgrammaticFocusUpdate] + 300 5 UIKitCore 0x0000000184e2e22c -[UIFocusSystem _requestFocusUpdate:] + 548 6 UIKitCore 0x0000000184e2dfa4 -[UIFocusSystem requestFocusUpdateToEnvironment:] + 76 7 UIKitCore 0x0000000184e2e864 -[UIFocusSystem _focusEnvironmentWillDisappear:] + 408 8 SpriteKit 0x00000001a3d472f4 _ZL12_removeChildP6SKNodeS0_P7SKScene + 240 9 SpriteKit 0x00000001a3d473b0 -[SKNode removeChild:] + 80 10 SpriteKit 0x00000001a3d466b8 -[SKNode removeFromParent] + 128 11 SpriteKit 0x00000001a3d1678c -[SKRemove updateWithTarget:forTime:] + 64 12 SpriteKit 0x00000001a3d1b740 _ZN11SKCSequence27cpp_updateWithTargetForTimeEP7SKCNoded + 84 13 SpriteKit 0x00000001a3d20e3c _ZN7SKCNode6updateEdf + 156 14 SpriteKit 0x00000001a3d20f20 _ZN7SKCNode6updateEdf + 384 15 SpriteKit 0x00000001a3d26fb8 -[SKScene _update:] + 464 16 SpriteKit 0x00000001a3cf3168 -[SKSCNRenderer _update:] + 80 17 SceneKit 0x000000019c932bf0 -[SCNMTLRenderContext renderSKSceneWithRenderer:overlay:atTime:] + 60 18 SceneKit 0x000000019c9ebd98 -[SCNRenderer _drawOverlaySceneAtTime:] + 204 19 SceneKit 0x000000019cb1a1c0 _ZN3C3D11OverlayPass7executeERKNS_10RenderArgsE + 60 20 SceneKit 0x000000019c8e05ec _ZN3C3D13__renderSliceEPNS_11RenderGraphEPNS_10RenderPassERtRKNS0_9GraphNodeERPNS0_5StageENS_10RenderArgsEbRPU27objcproto16MTLCommandBuffer11objc_object + 2660 21 SceneKit 0x000000019c8e18ac _ZN3C3D11RenderGraph7executeEv + 3808 22 SceneKit 0x000000019c9ed26c -[SCNRenderer _renderSceneWithEngineContext:sceneTime:] + 756 23 SceneKit 0x000000019c9ed544 -[SCNRenderer _drawSceneWithNewRenderer:] + 208 24 SceneKit 0x000000019c9ed9fc -[SCNRenderer _drawScene:] + 40 25 SceneKit 0x000000019c9edce4 -[SCNRenderer _drawAtTime:] + 500 26 SceneKit 0x000000019ca87950 -[SCNView _drawAtTime:] + 368 27 SceneKit 0x000000019c943b74 __83-[NSObject(SCN_DisplayLinkExtensions) SCN_setupDisplayLinkWithQueue:screen:policy:]_block_invoke + 44 28 SceneKit 0x000000019ca50600 -[SCNDisplayLink _displayLinkCallbackReturningImmediately] + 132 29 libdispatch.dylib 0x000000010239173c _dispatch_client_callout + 16 30 libdispatch.dylib 0x0000000102394c14 _dispatch_continuation_pop + 756 31 libdispatch.dylib 0x00000001023aa4e0 _dispatch_source_invoke + 1736 32 libdispatch.dylib 0x00000001023997f0 _dispatch_lane_serial_drain + 340 33 libdispatch.dylib 0x000000010239a774 _dispatch_lane_invoke + 420 34 libdispatch.dylib 0x00000001023a71a8 _dispatch_root_queue_drain_deferred_wlh + 324 35 libdispatch.dylib 0x00000001023a6604 _dispatch_workloop_worker_thread + 488 36 libsystem_pthread.dylib 0x000000010242bb74 _pthread_wqthread + 284 37 libsystem_pthread.dylib 0x000000010242a934 start_wqthread + 8 ) libc++abi: terminating due to uncaught exception of type NSException Am I doing something wrong?

I am trying to port SceneKit projects to Swift 6, and I just can't figure out how that's possible. I even start thinking SceneKit and Swift 6 concurrency just don't match together, and SceneKit projects should - hopefully for the time being only - stick to Swift 5. The SCNSceneRendererDelegate methods are called in the SceneKit Thread. If the delegate is a ViewController: class GameViewController: UIViewController { let aNode = SCNNode() func renderer(_ renderer: any SCNSceneRenderer, updateAtTime time: TimeInterval) { aNode.position.x = 10 } } Then the compiler generates the error "Main actor-isolated instance method 'renderer(_:updateAtTime:)' cannot be used to satisfy nonisolated protocol requirement" Which is fully understandable. The compiler even tells you those methods can't be used for protocol conformance, unless: Conformance is declare as @preconcurrency SCNSceneRendererDelegate like this: class GameViewController: UIViewController, @preconcurrency SCNSceneRendererDelegate { But that just delays the check to runtime, and therefore, crash in the SceneKit Thread happens at runtime... Again, fully understandable. or the delegate method is declared nonisolated like this: nonisolated func renderer(_ renderer: any SCNSceneRenderer, updateAtTime time: TimeInterval) { aNode.position.x = 10 } Which generates the compiler error: "Main actor-isolated property 'position' can not be mutated from a nonisolated context". Again fully understandable. If the delegate is not a ViewController but a nonisolated class, we also have the problem that SCNNode can't be used. Nearly 100% of the SCNSceneRendererDelegate I've seen do use SCNNode or similar MainActor bound types, because they are meant for that. So, where am I wrong ? What is the solution to use SceneKit SCNSceneRendererDelegate methods with full Swift 6 compilation ? Is that even possible for now ?

Hello dear forum, I need to emit an exact amount of particles from a SCNParticleSystem in a burst (this is for an UI effect). This worked for me perfectly in the scene editor by setting the birthrate to the amount and emission duration to 0. Sadly when I either load such a particle system from a scene or creating it by code, the emitted particles are sometimes one less, or one more. The first time I run it in the simulator, it seems to work fine but then amount of particles varies as described. video: https://youtube.com/shorts/MRzqWBy2ypA?feature=share Does anybody know how to make this predictable? Thanks so much in advance, Seb

There is a significant regression in Xcode 16.0 and 16.1 (16B5014f) in that it no longer allows asset files other than .SCN files to be added to a .scnasset group and folder. This really wrecks our ability to maintain our app since we heavily depend on additional assets like .USDZ, .JPEG, .PNG, etc. files to be able to be included in the group for on-demand resource tagging and loading. I filed FB15239224 but I'm wondering if this is intentional and if anyone knows of a workaround.

In my app, I have an ARView that has cameraMode set to nonAR. I occasionally hide the ARView when it is not needed and reveal it again later. While the ARView is hidden, I'd like to pause the animation to save iPhone battery life. I'd also like to do this when I know that animation in my scene has paused and the contents of the view, although still visible, is static. This was possible using SceneKit, but I can't seem to find an equivalent way to do it using RealityKit. At least as of iOS 18, a hidden ARView with an empty scene appears to use approximately 30% of the CPU. How can I pause ARView so that it won't use the battery unnecessarily? Thank you for considering this question.

Every now and then my SceneKit game app crashes and I have no idea why. The SCNView has a overlaySKScene, so it might also be SpriteKit's fault. The stack trace is #0 0x0000000241c1470c in jet_context::set_fragment_texture(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char>> const&, jet_texture*) () #27 0x000000010572fd40 in _pthread_wqthread () Does anyone have an idea where I could start debugging this, without being able to consistently reproduce it?

After scanning the room I use the .export method passing a ModelProvider. Then I import the USDZ into a SCNView and continue processing the scene: I would like to apply a texture to the walls and floor, but I can't do it for the walls and floor because they don't contain the TextureCoordinates. Creating them from the USDZ file is not easy. I tried to combine the CapturedRoom data for the walls and floor only, adding the TextureCoordinates. I'm managing, but I'm struggling a lot. Isn't there an easier way to do it? Is there a ModelProvider planned for surfaces in the future? If so, where can I access the RoomPlan beta documentation?

Hi everyone, I'm looking for a way to convert an FBX file to USDZ directly within my iOS app. I'm aware of Reality Converter and the Python USDZ converter tool, but I haven't been able to find any documentation on how to do this directly within the app (assuming the user can upload their own file). Any guidance on how to achieve this would be greatly appreciated. I've heard about Model I/O and SceneKit, but I haven't found much information on using them for this purpose either. Thanks!

Hello, I’m playing around with making an fully immersive multiplayer, air to air dogfighting game, but I’m having trouble figuring out how to attach a camera to an entity. I have a plane that’s controlled with a GamePad. And I want the camera’s position to be pinned to that entity as it moves about space, while maintaining the users ability to look around. Is this possible? -- From my understanding, the current state of SceneKit, ARKit, and RealityKit is a bit confusing with what can and can not be done. SceneKit Full control of the camera Not sure if it can use RealityKits ECS system. 2D Window. - Missing full immersion. ARKit Full control of the camera* - but only for non Vision Pro devices. Since Vision OS doesn't have a ARView. Has RealityKits ECS system 2D Window. - Missing full immersion. RealityKit Camera is pinned to the device's position and orientation Has RealityKits ECS system Allows full immersion