Integrate iOS device camera and motion features to produce augmented reality experiences in your app or game using ARKit.

ARKit Documentation

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Projecting a Cube with a Number in ARKit
I'm a novice in RealityKit and ARKit. I'm using ARKit in SwiftUI to show a cube with a number as shown below. import SwiftUI import RealityKit import ARKit struct ContentView : View { var body: some View { return ARViewContainer() } } #Preview { ContentView() } struct ARViewContainer: UIViewRepresentable { typealias UIViewType = ARView func makeUIView(context: UIViewRepresentableContext<ARViewContainer>) -> ARView { let arView = ARView(frame: .zero, cameraMode: .ar, automaticallyConfigureSession: true) arView.enableTapGesture() return arView } func updateUIView(_ uiView: ARView, context: UIViewRepresentableContext<ARViewContainer>) { } } extension ARView { func enableTapGesture() { let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(handleTap(recognizer:))) self.addGestureRecognizer(tapGestureRecognizer) } @objc func handleTap(recognizer: UITapGestureRecognizer) { let tapLocation = recognizer.location(in: self) // print("Tap location: \(tapLocation)") guard let rayResult = self.ray(through: tapLocation) else { return } let results = self.raycast(from: tapLocation, allowing: .estimatedPlane, alignment: .any) if let firstResult = results.first { let position = simd_make_float3(firstResult.worldTransform.columns.3) placeObject(at: position) } } func placeObject(at position: SIMD3<Float>) { let mesh = MeshResource.generateBox(size: 0.3) let material = SimpleMaterial(color: UIColor.systemRed, roughness: 0.3, isMetallic: true) let modelEntity = ModelEntity(mesh: mesh, materials: [material]) var unlitMaterial = UnlitMaterial() if let textureResource = generateTextResource(text: "1", textColor: UIColor.white) { unlitMaterial.color = .init(tint: .white, texture: .init(textureResource)) modelEntity.model?.materials = [unlitMaterial] let id = UUID().uuidString modelEntity.name = id modelEntity.transform.scale = [0.3, 0.1, 0.3] modelEntity.generateCollisionShapes(recursive: true) let anchorEntity = AnchorEntity(world: position) anchorEntity.addChild(modelEntity) self.scene.addAnchor(anchorEntity) } } func generateTextResource(text: String, textColor: UIColor) -> TextureResource? { if let image = text.image(withAttributes: [NSAttributedString.Key.foregroundColor: textColor], size: CGSize(width: 18, height: 18)), let cgImage = image.cgImage { let textureResource = try? TextureResource(image: cgImage, options: TextureResource.CreateOptions.init(semantic: nil)) return textureResource } return nil } } I tap the floor and get a cube with '1' as shown below. The background color of the cube is black, I guess. Where does this color come from and how can I change it into, say, red? Thanks.
4
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259
Jul ’25
VisionOS 26 - threadsPerThreadgroup limit causing crash on device (but not in simulator)
Hi all, I'm running into an issue with an app that previously worked fine on device using visionOS 2.0. After updating to visionOS 26, the same code runs fine in the simulator but crashes on the device with the following error: -[MTLDebugComputeCommandEncoder _validateThreadsPerThreadgroup:]:1330: failed assertion `(threadsPerThreadgroup.width(32) * threadsPerThreadgroup.height(32) * threadsPerThreadgroup.depth(1))(1024) must be <= 832. (kernel threadgroup size limit)` Is there any documented way to check or increase the allowed threadsPerThreadgroup size on Apple Vision Pro? Or any recommended workaround for this regression? Thanks in advance!
3
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267
Jun ’25
I need to troubleshoot Transform Drift in ARKit
Hi all, I'm currently developing a real-time object reconstruction app using ARKit. The goal is to scan large objects using ARKit’s depth and transform data, and generate a point cloud. However, I’m facing a major challenge - Transform Drift / World Alignment Issues The localToWorld transform provided by ARKit frequently seems to drift or become unstable across frames. This results in misaligned point clouds even when the device is moved slowly or kept relatively still. In some cases, a static surface scanned over a few seconds results in clearly misaligned fragments. This makes it difficult to accurately stitch a multi-frame point cloud. I have experimented with various lighting conditions and object textures, but the issue persists in all cases. At times, the relative error between frames reaches up to 20 cm, while in other instances the error is minimal; however, the drift gradually accumulates over time, leading to an overall enlargement of the reconstructed object. I have attached images of both cases here. Questions: Are there specific conditions under which ARKit’s world transform is expected to drift? Is there a way to detect or recover from this drift during runtime? Any best practices for maintaining consistent tracking during scanning or measurement sessions?
1
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197
Jun ’25
Possible contradiction between ARKit's definition of UIDeviceOrientation.landscapeRight and the actual definition of UIDeviceOrientation.landscapeRight
So it seems to be that there is a contradiction between how ARKit defines UIDeviceOrientation.landscapeRight, and the actual definition of UIDeviceOrientation.landscapeRight in the UIKit documentation. In the ARKit documentation for ARCamera.transform, it says the following: This transform creates a local coordinate space for the camera that is constant with respect to device orientation. In camera space, the x-axis points to the right when the device is in UIDeviceOrientation.landscapeRight orientation—that is, the x-axis always points along the long axis of the device, from the front-facing camera toward the Home button. The y-axis points upward (with respect to UIDeviceOrientation.landscapeRight orientation), and the z-axis points away from the device on the screen side. Going through the same link, we see the definition of UIDeviceOrientation.landscapeRight given as: The device is in landscape mode, with the device held upright and the front-facing camera on the right side. There seems to be a conflict in the two definitions, that has already been asked and visualized in this StackOverflow thread The resolution of that answer says that ARKit landscapeRight, unlike what is given in UIDeviceOrientation.landscapeRight, has home button on the right, as stated in the ARCamera.transform documentation. It says that more details are given in this StackOverflow thread, but this thread talks about the discrepancy between the definitions of landscapeRight in UIDeviceOrientation and UIInterfaceOrientation, and not anything related to ARKit. So I am wondering, why does ARKit definition of landscapeRight contradict with that of UIDeviceOrientation despite explicitly mentioning it? Is it just a mistake by Apple developers that hasn't been resolved even after so long?
1
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163
Jun ’25
ARKit camera transform orientation vector doesn't match physical device heading (despite `.gravityAndHeading`)
Hi all, I'm working on an ARKit-based iOS app where I need to accurately determine the direction the device is facing to localize objects in the real world. I'm using: let config = ARWorldTrackingConfiguration() config.worldAlignment = .gravityAndHeading Thus, I would expect the world alignment to behave as given in the gravityAndHeading page. The AR session is started after verifying that CLLocationManager.headingAccuracy <= 20, and the compass appears to be calibrated. However, I'm seeing a major inconsistency: When the rear camera is physically pointed toward true North, I would expect: cameraTransform.columns.2.z ≈ -1 // (i.e. ARKit's -Z pointing North) But instead, I'm consistently seeing: cameraTransform.columns.2.z ≈ +0.97 // Implies camera is facing South Meanwhile, the translation vector behaves as expected: As I physically move North, cameraTransform.columns.3.z becomes more negative, matching the world’s +Z = South assumption. For example, let's say I have the device in landscapeRight (or landscapeLeft for UIDeviceOrientation). Let's say the device rear camera is pointing towards True North, and I start moving towards True North. I get something like this: Camera Transform = simd_float4x4( [ [0.98446155, -0.030119859, 0.172998, 0.0], [0.023979114, 0.9990097, 0.037477385, 0.0], [-0.17395553, -0.032746706, 0.98420894, 0.0], [0.024039675, -0.037087332, -0.22780673, 0.99999994] ]) As you can see, the cameraTransform.columns.2.z is positive despite the rear camera pointing towards True North, while cameraTransform.columns.3.z is correctly positive as the device is moving towards True North. So here is my question: Why is cameraTransform.columns.2.z positive when the rear camera is physically facing North? Any clarity would be deeply appreciated. I've read the documentation and tested with different heading accuracies and AR session resets, but I keep running into this orientation mismatch. Thanks in advance!
1
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198
Jun ’25
ARKit sessionInterruptionEnded never called in Window Mode.
Hi 26 beta guys, I have apps using ARKit. In iPadOS 26 beta, ARKit stops working after switching to other apps. how to: Enable WindowMode in iPadOS 26 Launch my app and start ARSession Switch to another app (preference app, etc.) Switch back to my app AR stops updating camerafeed. I debug printed ARSessionDelegate, and found that after sessionWasInterrupted was called, sessionInterruptionEnded was never called. sessionInterruptionEnded is called if WindowMode disabled. Is this just a bug for 26 beta? I suspect there is similar problem with non-AR camera. Any idea?
2
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171
Jun ’25
Projecting a Cube with a Number in ARKit
I'm a novice in RealityKit and ARKit. I'm using ARKit in SwiftUI to show a cube with a number as shown below. import SwiftUI import RealityKit import ARKit struct ContentView : View { var body: some View { return ARViewContainer() } } #Preview { ContentView() } struct ARViewContainer: UIViewRepresentable { typealias UIViewType = ARView func makeUIView(context: UIViewRepresentableContext<ARViewContainer>) -> ARView { let arView = ARView(frame: .zero, cameraMode: .ar, automaticallyConfigureSession: true) arView.enableTapGesture() return arView } func updateUIView(_ uiView: ARView, context: UIViewRepresentableContext<ARViewContainer>) { } } extension ARView { func enableTapGesture() { let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(handleTap(recognizer:))) self.addGestureRecognizer(tapGestureRecognizer) } @objc func handleTap(recognizer: UITapGestureRecognizer) { let tapLocation = recognizer.location(in: self) // print("Tap location: \(tapLocation)") guard let rayResult = self.ray(through: tapLocation) else { return } let results = self.raycast(from: tapLocation, allowing: .estimatedPlane, alignment: .any) if let firstResult = results.first { let position = simd_make_float3(firstResult.worldTransform.columns.3) placeObject(at: position) } } func placeObject(at position: SIMD3<Float>) { let mesh = MeshResource.generateBox(size: 0.3) let material = SimpleMaterial(color: UIColor.systemRed, roughness: 0.3, isMetallic: true) let modelEntity = ModelEntity(mesh: mesh, materials: [material]) var unlitMaterial = UnlitMaterial() if let textureResource = generateTextResource(text: "1", textColor: UIColor.white) { unlitMaterial.color = .init(tint: .white, texture: .init(textureResource)) modelEntity.model?.materials = [unlitMaterial] let id = UUID().uuidString modelEntity.name = id modelEntity.transform.scale = [0.3, 0.1, 0.3] modelEntity.generateCollisionShapes(recursive: true) let anchorEntity = AnchorEntity(world: position) anchorEntity.addChild(modelEntity) self.scene.addAnchor(anchorEntity) } } func generateTextResource(text: String, textColor: UIColor) -> TextureResource? { if let image = text.image(withAttributes: [NSAttributedString.Key.foregroundColor: textColor], size: CGSize(width: 18, height: 18)), let cgImage = image.cgImage { let textureResource = try? TextureResource(image: cgImage, options: TextureResource.CreateOptions.init(semantic: nil)) return textureResource } return nil } } I tap the floor and get a cube with '1' as shown below. The background color of the cube is black, I guess. Where does this color come from and how can I change it into, say, red? Thanks.
Replies
4
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0
Views
259
Activity
Jul ’25
VisionOS 26 - threadsPerThreadgroup limit causing crash on device (but not in simulator)
Hi all, I'm running into an issue with an app that previously worked fine on device using visionOS 2.0. After updating to visionOS 26, the same code runs fine in the simulator but crashes on the device with the following error: -[MTLDebugComputeCommandEncoder _validateThreadsPerThreadgroup:]:1330: failed assertion `(threadsPerThreadgroup.width(32) * threadsPerThreadgroup.height(32) * threadsPerThreadgroup.depth(1))(1024) must be <= 832. (kernel threadgroup size limit)` Is there any documented way to check or increase the allowed threadsPerThreadgroup size on Apple Vision Pro? Or any recommended workaround for this regression? Thanks in advance!
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3
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0
Views
267
Activity
Jun ’25
I need to troubleshoot Transform Drift in ARKit
Hi all, I'm currently developing a real-time object reconstruction app using ARKit. The goal is to scan large objects using ARKit’s depth and transform data, and generate a point cloud. However, I’m facing a major challenge - Transform Drift / World Alignment Issues The localToWorld transform provided by ARKit frequently seems to drift or become unstable across frames. This results in misaligned point clouds even when the device is moved slowly or kept relatively still. In some cases, a static surface scanned over a few seconds results in clearly misaligned fragments. This makes it difficult to accurately stitch a multi-frame point cloud. I have experimented with various lighting conditions and object textures, but the issue persists in all cases. At times, the relative error between frames reaches up to 20 cm, while in other instances the error is minimal; however, the drift gradually accumulates over time, leading to an overall enlargement of the reconstructed object. I have attached images of both cases here. Questions: Are there specific conditions under which ARKit’s world transform is expected to drift? Is there a way to detect or recover from this drift during runtime? Any best practices for maintaining consistent tracking during scanning or measurement sessions?
Replies
1
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0
Views
197
Activity
Jun ’25
Having Issues In ARViewContainer Code
My ARViewContainer code is not working. I don't know how to debug the issue and I don't know or see where my results is going to. I need help to resolve this issue. please help debug. See code below:
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3
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0
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140
Activity
Jun ’25
RemoteImmersiveSpace sample isn't working
Hello RemoteDeviceIdentifier returns nil and therefore it crashes the HoverEffect sample project. I have vision26 beta 2 on both devices what the correct method of running this code sample ?
Replies
3
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0
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251
Activity
Jun ’25
Possible contradiction between ARKit's definition of UIDeviceOrientation.landscapeRight and the actual definition of UIDeviceOrientation.landscapeRight
So it seems to be that there is a contradiction between how ARKit defines UIDeviceOrientation.landscapeRight, and the actual definition of UIDeviceOrientation.landscapeRight in the UIKit documentation. In the ARKit documentation for ARCamera.transform, it says the following: This transform creates a local coordinate space for the camera that is constant with respect to device orientation. In camera space, the x-axis points to the right when the device is in UIDeviceOrientation.landscapeRight orientation—that is, the x-axis always points along the long axis of the device, from the front-facing camera toward the Home button. The y-axis points upward (with respect to UIDeviceOrientation.landscapeRight orientation), and the z-axis points away from the device on the screen side. Going through the same link, we see the definition of UIDeviceOrientation.landscapeRight given as: The device is in landscape mode, with the device held upright and the front-facing camera on the right side. There seems to be a conflict in the two definitions, that has already been asked and visualized in this StackOverflow thread The resolution of that answer says that ARKit landscapeRight, unlike what is given in UIDeviceOrientation.landscapeRight, has home button on the right, as stated in the ARCamera.transform documentation. It says that more details are given in this StackOverflow thread, but this thread talks about the discrepancy between the definitions of landscapeRight in UIDeviceOrientation and UIInterfaceOrientation, and not anything related to ARKit. So I am wondering, why does ARKit definition of landscapeRight contradict with that of UIDeviceOrientation despite explicitly mentioning it? Is it just a mistake by Apple developers that hasn't been resolved even after so long?
Replies
1
Boosts
0
Views
163
Activity
Jun ’25
ARKit camera transform orientation vector doesn't match physical device heading (despite `.gravityAndHeading`)
Hi all, I'm working on an ARKit-based iOS app where I need to accurately determine the direction the device is facing to localize objects in the real world. I'm using: let config = ARWorldTrackingConfiguration() config.worldAlignment = .gravityAndHeading Thus, I would expect the world alignment to behave as given in the gravityAndHeading page. The AR session is started after verifying that CLLocationManager.headingAccuracy <= 20, and the compass appears to be calibrated. However, I'm seeing a major inconsistency: When the rear camera is physically pointed toward true North, I would expect: cameraTransform.columns.2.z ≈ -1 // (i.e. ARKit's -Z pointing North) But instead, I'm consistently seeing: cameraTransform.columns.2.z ≈ +0.97 // Implies camera is facing South Meanwhile, the translation vector behaves as expected: As I physically move North, cameraTransform.columns.3.z becomes more negative, matching the world’s +Z = South assumption. For example, let's say I have the device in landscapeRight (or landscapeLeft for UIDeviceOrientation). Let's say the device rear camera is pointing towards True North, and I start moving towards True North. I get something like this: Camera Transform = simd_float4x4( [ [0.98446155, -0.030119859, 0.172998, 0.0], [0.023979114, 0.9990097, 0.037477385, 0.0], [-0.17395553, -0.032746706, 0.98420894, 0.0], [0.024039675, -0.037087332, -0.22780673, 0.99999994] ]) As you can see, the cameraTransform.columns.2.z is positive despite the rear camera pointing towards True North, while cameraTransform.columns.3.z is correctly positive as the device is moving towards True North. So here is my question: Why is cameraTransform.columns.2.z positive when the rear camera is physically facing North? Any clarity would be deeply appreciated. I've read the documentation and tested with different heading accuracies and AR session resets, but I keep running into this orientation mismatch. Thanks in advance!
Replies
1
Boosts
0
Views
198
Activity
Jun ’25
ARKit sessionInterruptionEnded never called in Window Mode.
Hi 26 beta guys, I have apps using ARKit. In iPadOS 26 beta, ARKit stops working after switching to other apps. how to: Enable WindowMode in iPadOS 26 Launch my app and start ARSession Switch to another app (preference app, etc.) Switch back to my app AR stops updating camerafeed. I debug printed ARSessionDelegate, and found that after sessionWasInterrupted was called, sessionInterruptionEnded was never called. sessionInterruptionEnded is called if WindowMode disabled. Is this just a bug for 26 beta? I suspect there is similar problem with non-AR camera. Any idea?
Replies
2
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0
Views
171
Activity
Jun ’25
Has iOS26 brought anything new to RoomPlan?
With iOS26 unveiled, has anyone noticed or found any changes related to RoomPlan? I can't find anything myself, which is disappointing. Has anyone found any improvements or changes?
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0
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1
Views
308
Activity
Jun ’25