RealityKit

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Simulate and render 3D content for use in your augmented reality apps using RealityKit.

RealityKit Documentation

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Per-vertex color. in a custom RealityKit mesh? (macOS)
I'm working on an application for viewing AMF models on macOS, using RealityKit. AMF supports several different ways to color models, including per-vertex color (where the color of a triangle is interpolated from vertex to vertex) as well as per-face color (where the color of the triangle is the same across the entire face). I'm trying to figure out how to support those color models using a RealityKit mesh. Apple's documentation (https://developer.apple.com/documentation/realitykit/modifying-realitykit-rendering-using-custom-materials) talks about per-vertex colors, but I haven't found a way to create a mesh that includes per-vertex colors, other than use a texture map (which might be the correct solution). Can someone give me some pointers?
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USDZ files with camera can't be opened on IOS 18.2/iPadOS 18.2 correctly.
Hi experts, When I open a USDZ file which contains perspective cameras by "Files" app in IOS 18.2/iPadOS 18.2, I can't see anything. And when I open the USDZ file in IOS 18.1/iPadOS 18.1, it works well. On the other hand, when I open a USDZ file which contains orthographic cameras in IOS 18.1 or IOS 18.2, the scene is stuck. Could you help to solve these issues please? Thanks.
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Dec ’24
Spatial Scene API for iOS Apps
As part of the WWDC25 Keynote, a technology was announced that can present 2D images as 3D spatial scenes. This announcement is supported by a Press Release. ...developers can use the Spatial Scene API to make their app experience even more immersive. Zillow is taking advantage of the API for their Zillow Immersive app, allowing users to see images of homes and apartments with the rich depth and dimension that spatial scenes offer. The feature also appears in the Photos App on iOS 26 Developer Beta 1. Tapping "Spatial Scene" on any photo opens a view of that photo with a parallax effect. I've searched the WWDC sessions and new documentation and have come up short. Reaching out here for help. Is there any documentation for Spatial Scene API? Or any guidance on how to implement the spatial scene in iOS?
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Jun ’25
How to attach SwiftUI Views to entities on non-visionOS platforms?
What is the recommended way to attach SwiftUI views to RealityKit entities on macOS, iOS, etc? All the APIs seem to be visionOS only: https://developer.apple.com/documentation/realitykit/realityviewattachments https://developer.apple.com/documentation/realitykit/viewattachmentcomponent https://developer.apple.com/documentation/realitykit/presentationcomponent https://developer.apple.com/documentation/realitykit/imagepresentationcomponent My only idea is to do it "manually" with a ZStack and RealityView somehow? I submitted this as a feedback since it seemed like an oversight: FB18034856.
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Jun ’25
Is migrating from ARView to RealityView recommended?
We're using RealityKit to create a science education AR app for iOS, iPadOS, and visionOS. In the WWDC25 session video "Bring your SceneKit project to RealityKit" https://developer.apple.com/videos/play/wwdc2025/288 at 8:15, it's explained that when using RealityKit, RealityView should be used in all cases, whereas in the past, SceneKit required SCNView, SceneView, or ARSCNView, depending on an app's requirements. Because the initial development of our app on iOS predates iOS 18's RealityView, our app currently uses ARView to render RealityKit AR content on iOS and iPadOS. Is it recommended that we migrate to RealityView, or can we safely continue using our existing ARView implementation? We'd prefer to avoid unnecessary development cost. If migrating from ARView to RealityView is recommended, what specific benefits should we expect from this transition? Thank you.
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Jun ’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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Jul ’25
GestureComponent does not support DragGesture
The following code using the new GestureComponent demonstrates inconsistency. The tap gesture prints output, but the drag gesture does not. I already checked this post, which points to this seemingly outdated sample code I assume that example is deprecated in favour of the now built in version of GestureComponent. Nonetheless, there are no compiler warnings or errors, it just fails silently. TapGesture, LongPressGesture, MagnifyGesture, RotateGesture all work, so this feels like an oversight. RealityView { content in let testEntity = ModelEntity(mesh: .generateBox(size: .init(x: 1, y: 1, z: 1))) testEntity.position = SIMD3<Float>(0,0,-1) testEntity.components.set(InputTargetComponent()) testEntity.components.set(CollisionComponent( shapes: [.generateBox(size: .init(x: 1, y: 1, z: 1))] )) let testGesture = TapGesture() .onEnded { value in print("Tapped") } testEntity.components.set(GestureComponent(testGesture)) let dragGesture = DragGesture() .onEnded { value in print("Dragged") } testEntity.components.set(GestureComponent(dragGesture)) content.add(testEntity) }
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Jul ’25
PhotogrammetrySession fails with internal errors 4011 / 4012 when using iOS Object Capture (Area Mode) images
Hi all, I’m running into an issue when trying to reconstruct a 3D model using PhotogrammetrySession on macOS from a set of images captured via the iOS Object Capture sample app, specifically in Area mode. When I attempt to create the model from these images (using the raw Images/ folder exported directly from the capture session), I get the following errors: ERROR cv3dapi.pg: Internal error codes (2): 4011 4012 WARN cv3dapi.pg: Internal warning codes (1): 4507 Output error with code = -15 requestError: CoreOC.PhotogrammetrySession.Error.processError I use the "Images" directory directly exported from Object Capture with my iphone 12 pro max (has lidar) set to "area mode" in the object capture app here is an example heic image metadata from the sequence. heif-info Images/00044.869568833.HEIC MIME type: image/heic main brand: heic compatible brands: mif1, MiHE, MiPr, miaf, MiHB, heic image: 3024x4032 (id=49), primary tiles: 6x8, tile size: 512x512 colorspace: YCbCr, 4:2:0 bit depth: 8 thumbnail: 240x320 color profile: nclx alpha channel: no depth channel: yes size: 192x256 bits per pixel: 8 z-near: 1.173828 z-far: 2.552734 d-min: undefined d-max: undefined representation: uniform Z metadata: Exif: 960 bytes uri /tag:apple.com,2023:ObjectCapture#CameraTrackingState: 4 bytes uri /tag:apple.com,2023:ObjectCapture#CameraCalibrationData: 1015 bytes uri /tag:apple.com,2023:ObjectCapture#ObjectTransform: 48 bytes uri /tag:apple.com,2023:ObjectCapture#ObjectBoundingBox: 48 bytes uri /tag:apple.com,2023:ObjectCapture#RawFeaturePoints: 832 bytes uri /tag:apple.com,2023:ObjectCapture#PointCloudData: 23984 bytes uri /tag:apple.com,2023:ObjectCapture#BundleVersion: 5 bytes uri /tag:apple.com,2023:ObjectCapture#SegmentID: 4 bytes uri /tag:apple.com,2024:ObjectCapture#SessionUUID: 36 bytes uri /tag:apple.com,2024:ObjectCapture#CaptureMode: 4 bytes uri /tag:apple.com,2023:ObjectCapture#Feedback: 4 bytes uri /tag:apple.com,2023:ObjectCapture#WideToDepthCameraTransform: 48 bytes uri /tag:apple.com,2023:ObjectCapture#TemporalDepthPointClouds: 864026 bytes transformations: angle (ccw): 270 region annotations: none properties: camera intrinsic matrix: focal length: 2813.695557; 2813.695557 principal point: 1522.338502; 2002.843018 skew: 0.000000 camera extrinsic matrix: rotation matrix: -0.695 0.344 -0.632 0.007 -0.875 -0.483 -0.719 -0.340 0.606 Questions: • What do internal error codes 4011 and 4012 refer to? • Is there something specific about Area mode captures that require preprocessing before they’re compatible with PhotogrammetrySession? • Has anyone successfully reconstructed a model from an Area mode session using the stock Apple tools? NOTE: I can provide the folder of images for debugging if that would help!
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Jul ’25
RealityKit captureHighResolutionFrame from session is broken on iOS26?
A bit of background on what our app is doing: We have a RealityKit ARView session running. During this period we place objects in RealityKit. At some point user can "take photo" and we use session.captureHighResolutionFrame to capture a frame. We then use captured frame and frame.camera.projectPoint to project my objects back to 2D Issue we found is that on devices that have iOS26, first photo user takes and the first frame received from session.captureHighResolutionFrame gives incorrect CGPoint for frame.camera.projectPoint. If user takes the second photo with the same camera phostion, second frame received from session.captureHighResolutionFrame gives correct CGPoint for frame.camera.projectPoint I notices some difference between first and subsequent frames that i believe is corresponding with the issue. Yaw value of camera (frame.camera.eulerAngles.y) on first frame is not correct ( inconsistent with any subsequent frame) I also created a small example app and i followed Building an Immersive Experience with RealityKit example to create it. The issue exists in this app for iOS26, while iOS18.* has consistent values between first and subsequent captured frames. Note: The yaw value seems to differ more if we start session in portrait but take photo in landscape. Example result for 3 captured frames: Frame captured with yaw: 1.4855177402496338 Frame captured with yaw: -0.08803760260343552 Frame captured with yaw: -0.08179682493209839 Example code: class CustomARView: ARView, ARSessionDelegate { required init(frame: CGRect) { super.init(frame: frame) } required init?(coder decoder: NSCoder) { fatalError("init(coder:) has not been implemented")} func setup() { let singleTap = UITapGestureRecognizer(target: self, action: #selector(handleTap)) addGestureRecognizer(singleTap) } @objc func handleTap(_ gestureRecognizer: UIGestureRecognizer) { Task { do { let frame = try await session.captureHighResolutionFrame() print("Frame captured with yaw: \(Double(frame.camera.eulerAngles.y))") } catch { } } } } struct CustomARViewUIViewRepresentable: UIViewRepresentable { func makeUIView(context: Context) -> some UIView { let arView = CustomARView(frame: .zero) arView.setup() return arView } func updateUIView(_ uiView: UIViewType, context: Context) { } } struct ContentView: View { var body: some View { CustomARViewUIViewRepresentable() .frame(maxWidth: .infinity, maxHeight: .infinity) .ignoresSafeArea() } }
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Sep ’25
Pink Screen with VideoMaterial in ARKit
Hi everyone, I'm developing an ARKit app using RealityKit and encountering an issue where a video displayed on a 3D plane shows up as a pink screen instead of the actual video content. Here's a simplified version of my setup: func createVideoScreen(video: AVPlayerItem, canvasWidth: Float, canvasHeight: Float, aspectRatio: Float, fitsWidth: Bool = true) -> ModelEntity { let width = (fitsWidth) ? canvasWidth : canvasHeight * aspectRatio let height = (fitsWidth) ? canvasWidth * (1/aspectRatio) : canvasHeight let screenPlane = MeshResource.generatePlane(width: width, depth: height) let videoMaterial: Material = createVideoMaterial(videoItem: video) let videoScreenModel = ModelEntity(mesh: screenPlane, materials: [videoMaterial]) return videoScreenModel } func createVideoMaterial(videoItem: AVPlayerItem) -> VideoMaterial { let player = AVPlayer(playerItem: videoItem) let videoMaterial = VideoMaterial(avPlayer: player) player.play() return videoMaterial } Despite following the standard process, the video plane renders pink. Has anyone encountered this before, or does anyone know what might be causing it? Thanks in advance!
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May ’25
BlendShapes don’t animate while playing animation in RealityKit
Hi everyone, I’m running into an issue with RealityKit when trying to animate BlendShapes (ShapeKeys) while a skeletal animation is playing. The model is a rigged character in .usdz format with both predefined skeletal animations and BlendShapes (exported from Blender). The problem: when I play any animation using entity.playAnimation(...), the BlendShapes stop responding. Calling setBlendShapes(...) still logs that weights are being updated, but the visual changes are not visible. The exact same blend shape animation works perfectly when no animation is playing. In SceneKit the same model works as expected: shape keys get animated during animation playback. But not in realitykit Still, as soon as an animation starts, the shape keys don’t animate anymore. Here’s the test project on GitHub that demonstrates the issue clearly: https://github.com/IAMTHEBURT/RealityKitWitnBlendShapesSample The goal is to play facial expressions (like blinking or talking) while a body animation (like waving) is playing. Is this a known limitation in RealityKit? Or is there a recommended way to combine skeletal animations with real-time BlendShape updates? Thanks in advance for any insights.
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Jul ’25
Showing a MTLTexture on an Entity in RealityKit
Is there any standard way of efficiently showing a MTLTexture on a RealityKit Entity? I can't find anything proper on how to , for example, generate a LowLevelTexture out of a MTLTexture. Closest match was this two year old thread. In the old SceneKit app, we would just do guard let material = someNode.geometry?.materials.first else { return } material.diffuse.contents = mtlTexture Our flow is as follows (for visualizing the currently detected object): Camera-Stream -> CoreML Segmentation -> Send the relevant part of the MLShapedArray-Tensor to a MTLComputeShader that returns a MTLTexture -> Show the resulting texture on a 3D object to the user
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Sep ’25
Sample code for WWDC25 Session
Hi! I watched the WWDC25 session "Bring your SceneKit project to RealityKit" which seemed like a great resource for those of us transitioning from the now-deprecated SceneKit framework. The session mentioned that the full sample code for the project would be available to download, but I haven't been able to find it in the Code section of the video page or in the Sample Code Library. Has the sample code been released yet? Having the project code would make it much easier to follow along with the RealityKit changes shown in the video. Thanks again for the great session.
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Jun ’25
Export Armatures from Blender to USDC for use in RealityKit
I'm an experienced SceneKit developer and I want to begin work on a new project using RealityKit. So I appreciated as timely, the WWDC 2025 Session, "Bring your SceneKit project to RealityKit". However, now I am finding that: Blender does not properly support exporting armatures in usdc files, and usdc is really the only file format that should be used for creating 3D assets for RealityKit. The option of exporting from Blender to fbx or some other intermediate format, and then converting that to usdc, is a challenge. Apple's Reality Converter App, which supposedly can support importing and converting fbx files to usdc, is no longer available from Apple's website. And an older copy of it I found at the Kodeco website requires Rosetta on Apple Silicon. As well, this older copy does not in fact import fbx or anything else - I find it doesn't work at all. Apple's Reality Composer Pro, at least as far as I can tell, only supports importing usdc - it is not a file conversion tool. Alternatively, I am under the impression that Maya supports producing usdc files with armatures, but Maya costs over $2000 per year and I am skilled with Blender, so I believe strongly that I should be able to continue with Blender. Maya's expense and skillset simply shouldn't be a requirement for building RealityKit applications. What are my options then, if any, to produce assets with armatures and armature based animations using Blender, and then bring them into RealityKit?
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Jun ’25
Scene with over 12,000 duplicate entities
I am creating a RealityKit scene that will contain over 12,000 duplicate cubes arranged in a circle (see image below). This is for some high-energy physical simulations I am doing. I accomplish this scene by creating a single cube and cloning it a bunch of times. So, I there is a single MeshResource and Material even though there are a lot of entities. I have confirmed this by checking with Swift's === operator. Even with this, the program is unworkably slow. Any suggestions or tricks that could help with this type of scene? Using a single geometry was the trick to getting SceneKit to work fast with geometries like this. I've been updating my software to RealityKit because I far prefer the structure of RealityKit over SceneKit.
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Jan ’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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Oct ’25
RealityKit visionOS anchor to POV
Hi, is there a way in visionOS to anchor an entity to the POV via RealityKit? I need an entity which is always fixed to the 'camera'. I'm aware that this is discouraged from a design perspective as it can be visually distracting. In my case though I want to use it to attach a fixed collider entity, so that the camera can collide with objects in the scene. Edit: ARView on iOS has a lot of very useful helper properties and functions like cameraTransform (https://developer.apple.com/documentation/realitykit/arview/cameratransform) How would I get this information on visionOS? RealityViews content does not seem offer anything comparable. An example use case would be that I would like to add an entity to the scene at my users eye-level, basically depending on their height. I found https://developer.apple.com/documentation/realitykit/realityrenderer which has an activeCamera property but so far it's unclear to me in which context RealityRenderer is used and how I could access it. Appreciate any hints, thanks!
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Dec ’24