I'm seeking detailed information about the rotation matrix of the iPhone's front-facing (selfie) camera when using ARKit.
Specifically, I need to understand:
The exact rotation matrix applied to the front-facing camera's output in ARKit.
Whether this matrix is consistent across all iPhone models or if there are variations.
If there are any transformations applied to align the camera's coordinate system with the device's orientation, particularly in portrait mode.
How this rotation matrix relates to the transform property of `ARFrame.camera
Discuss spatial computing on Apple platforms and how to design and build an entirely new universe of apps and games for Apple Vision Pro.
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Hi, I’m working on a portfolio project for Vision Pro these days.
I have two projects and each of projects are made with Unity and made with Xcode(using ARKit and RealityKit tracking feature). Is it able to combine these two projects in an app?
For example, using the buttons made with SwiftUI in a Reality Composer Pro, jumping to a scene in Unity, and back from a scene in Unity to a scene in Reality Composer Pro in an app.
Hi, currently tinkering with a little shareplay app for the Vision Pro that allows people to facetime and shareplay to play with random 3d models (as well as move them around, which should sync the model positions for everyone in relative space).
When the users start their facetime call, then open the immersive space to see the 3d models, the models load in properly in context of the group immersive space's coordinate system, and moving the models reflects the new positions real-time for each participant.
The main issue comes if/when users use the digital crown to re-center their view. It appears to re-center the model and view, which is expected. However, it also seems to re-position the model/root entity to match the user's origin. Not sure if this is intentional or not, but this essentially makes it so that it "de-syncs" the model (so me moving the model next to someone does not reflect it 1:1 - it still moves properly, but the new "initial" position after re-centering makes it offset).
Is there a potential solution or work-around for this such that re-centering the view doesn't de-sync the model/entity's position?
Rough code for my RealityView component is below:
RealityView { content, attachments in
content.add(appModel.originEntity)
appModel.originEntity.addChild(appModel.modelContainerEntity)
appModel.setInitialModelPosition()
configureGestures(forModel: appModel.modelContainerEntity)
configureToolbarAttachment(content: content, attachments: attachments)
} update: { content, _ in
// I have modified the Apple provided gesture components to
// send the app model the new positions/rotations
// as well as broadcast the position/rotation to shareplay participants
// When user re-centers view, it seems to also re-position the model
// so that its origin is at the local user's origin, rather than
// the original origin
// Can we receive a notification that user has re-centered view?
// Or some other work-around?
appModel.modelContainerEntity.setPosition(appModel.modelState.position, relativeTo: nil)
appModel.modelContainerEntity.setOrientation(.init(appModel.modelState.rotation3d), relativeTo: nil)
} attachments: {
Attachment(id: "customViewAttachment") {
CustomView()
}
}
.installGestures()
Please let me know if anything wasn't clear or if more information is needed. Thanks!
if you check the code here,
https://developer.apple.com/documentation/compositorservices/interacting-with-virtual-content-blended-with-passthrough
var body: some Scene {
ImmersiveSpace(id: Self.id) {
CompositorLayer(configuration: ContentStageConfiguration()) { layerRenderer in
let pathCollection: PathCollection
do {
pathCollection = try PathCollection(layerRenderer: layerRenderer)
} catch {
fatalError("Failed to create path collection \(error)")
}
let tintRenderer: TintRenderer
do {
tintRenderer = try TintRenderer(layerRenderer: layerRenderer)
} catch {
fatalError("Failed to create tint renderer \(error)")
}
Task(priority: .high) { @RendererActor in
Task { @MainActor in
appModel.pathCollection = pathCollection
appModel.tintRenderer = tintRenderer
}
let renderer = try await Renderer(layerRenderer,
appModel,
pathCollection,
tintRenderer)
try await renderer.renderLoop()
Task { @MainActor in
appModel.pathCollection = nil
appModel.tintRenderer = nil
}
}
layerRenderer.onSpatialEvent = {
pathCollection.addEvents(eventCollection: $0)
}
}
}
.immersionStyle(selection: .constant(appModel.immersionStyle), in: .mixed, .full)
.upperLimbVisibility(appModel.upperLimbVisibility)
the only way it's dealing with the error is fatalError.
And don't think I can throw anything or return anything else?
Is there a way I can gracefully handle this and show a message box in UI?
I was hoping I could somehow trigger a failure and have https://developer.apple.com/documentation/swiftui/openimmersivespaceaction return fail.
but couldn't find a nice way to do so.
Let me know if you have ideas.
As the title states, this severely limits the flexibility of multi-window applications in creating a good user experience.
Even effects like the ones shown below cannot be achieved.
Hi everyone,
I'm looking for some guidance on how to create an .arobject file. Is there a way to generate it from a 3D model (like a .objcap or .usdz or .fbx/.obj file)? Or can it only be generated by scanning a real-world object using the ARKitScanner project? Any advice or resources on this would be greatly appreciated!
I've only found this project for scanning real-world objects.
Thanks in advance!
Hello Apple Team,
Is it possible to change the zoom factor, exposure, white balance and other settings, of an iOS ARKit session?
I know how to do it using an AVCaptureSession,
however, I can't figure out how to access the AVCaptureDeviceInput of the current AR session.
Thanks
PS: I'm using ARkit and RealityKit on iOS 17
I am new here, my name is Axel - Hi! 👋 I am both a visionOS beginner and an expert in things 3D, now figuring my way into Reality Composer Pro. Most things are intuitive and easy to understand, yet there is one thing I cannot seem to figure out, and I feel really stupid because it must be there, and that's Keyframing: I would simply make a new Timeline and animate published parameters in a Shader Graph over time.
I know how to do this via Xcode and Custom Components, but that can't be it because that will break even on simple to medium animation in terms of previewing and fine-tuning, complete overkill for a simple value animation. Since key framing is the most basic functionality of 3D apps next to move, I am sure it is in RCP somewhere.
Anyone got a pointer for me?
I found that there is such a click-to-expand horizontally and smoothly effect in the system application called "message", which is good. I wonder if I can add a similar effect to my own app. If possible, are there any implementation ideas or examples that I can refer to? Thanks!
Hi everyone,
I need to synchronize the playback of RealityKit Timelines via SharePlay.
To do this I am trying to get the references of the timelines using "AnimationPlaybackController" and "AnimationResource". In my realitykit scene I have configured both an animation (with blender), and a timeline, the animation starts correctly when the realitykit scene starts, the timeline not.
Below the code:
struct ContentView: View {
@State private var subscriptions = [EventSubscription]()
@Environment(AppModel.self)
private var appModel
let rootEntity = Entity()
@State var testEntity: Entity?
@State var testAnimation: AnimationResource?
@State var testController: AnimationPlaybackController?
init() {
CubeComponent.registerComponent()
}
var body: some View {
RealityView { content in
content.add(rootEntity)
if let scene = try? await Entity(named: "Room", in: realityKitContentBundle) {
rootEntity.addChild(scene)
playAnimations(from: content)
}
}
.gesture(SpatialTapGesture().targetedToAnyEntity()
.onEnded({ value in
_ = value.entity.applyTapForBehaviors()
if let testEntity, let testAnimation {
testController = testEntity.playAnimation(testAnimation.repeat())
}
})
)
}
func playAnimations(from content: RealityViewContent) {
subscriptions.append(content.subscribe(to: ComponentEvents.DidAdd.self, componentType: AnimationLibraryComponent.self, { event in
let entity = event.entity
entity.components[AnimationLibraryComponent.self]?.animations.forEach({ (key, value) in
if value.definition is AnimationGroup {
if key == "/Room/TestTimeline" {
let controller = entity.playAnimation(value.repeat())
testEntity = entity
testAnimation = value
appModel.syncronizedAnimations[key] = .init(name: key, animationController: controller, entityName: entity.name)
}
} else {
if entity.name == "SphereInteractable" {
let controller = entity.playAnimation(value.repeat())
appModel.syncronizedAnimations[key] = .init(name: key, animationController: controller, entityName: entity.name)
}
}
})
}))
}
}
the variables testEntity, testAnimation and testController are for testing purposes only. If I try to start the animations in the playAnimations function, only the animation created via blender starts (the one related to the object "SphereInteractable"), the Timeline starts only if I save a reference and I play it with a tap gesture or with a delay of ! seconds with DispatchQueue.asyncAfter called in the onAppear.
is there a better way to handle this? The goal is to have a reference of the AnimationPlaybackController of the timeline, in order to sync the animation via shareplay.
Thanks
I've tried importing a 3D KTX file into Reality Composer Pro ShaderGraph, but got nothing output. Realitykit doesn't support Image3D yet?
First, I use pyktx to create a 3D KTX texture file and it seems correct in Finder preview.
import numpy as np
from pyktx import KtxTexture2, KtxTextureCreateInfo, KtxTextureCreateStorage, VkFormat
size = 32
image = np.zeros((size, size, size, 3), dtype=np.uint8)
for i in range(size):
image[i, :, :, 0] = np.interp(i, [0, size], [50, 255])
image[:, i, :, 1] = np.interp(i, [0, size], [100, 255])
image[:, :, i, 2] = np.interp(i, [0, size], [150, 255])
info = KtxTextureCreateInfo(
gl_internal_format=None,
vk_format=VkFormat.VK_FORMAT_R8G8B8_SRGB,
base_width=image.shape[2],
base_height=image.shape[1],
base_depth=image.shape[0],
num_dimensions=3,
num_levels=1,
num_layers=1,
num_faces=1,
generate_mipmaps=False,
is_array=False,
)
texture = KtxTexture2.create(info, KtxTextureCreateStorage.ALLOC)
for _ in range(1):
texture.set_image_from_memory(0, 0, _, image[_].tobytes())
texture.write_to_named_file(f'{size}.ktx')
Then I import it into ShaderGraph like this but seems nothing could be read.
In addition, I tested 2D KTX file and it worked.
I also tested different vk_format or KTX1/KTX2 but did not work.
I also tested Image3DPixel/Image2DArray/Image3DRead and none of them work as long as it's 3D.
I am able to create a custom node graph by selecting nodes and then choosing the "Compose Node Graph" option in the context menu. After that, when I select my custom node graph, I see in the top-right panel that it is possible to define inputs and outputs. However, I was not able to figure out how to link those to the inputs and outputs in the underlying nodes.
Hi, I am trying to stream spatial video in realtime from my iPhone 16.
I am able to record spatial video as a file output using:
let videoDeviceOutput = AVCaptureMovieFileOutput()
However, when I try to grab the raw sample buffer, it doesn't include any spatial information:
let captureOutput = AVCaptureVideoDataOutput()
//when init camera
session.addOutput(captureOutput)
captureOutput.setSampleBufferDelegate(self, queue: sessionQueue)
//finally
func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
//use sample buffer (but no spatial data available here)
}
Is this how it's supposed to work or maybe I am missing something?
this video: https://developer.apple.com/videos/play/wwdc2023/10071 gives us a clue towards setting up spatial streaming and I've got the backend all ready for 3D HLS streaming. Now I am only stuck at how to send the video stream to my server.
As you can see, it is a transparent spherical shell model with a ball inside. Everything is normal on the front side, but there are strange mesh triangles on the side and back view. I don't know if this is as expected and what I need to do to remove these strange effects.
On visionOS, I have discovered that if dismissWindow is followed immediately by a call to openWindow, the new window does not open where the user is looking at. Instead, it appears at the same location as the dismissed window. However, if I open the new window after a small delay, or after UIScene's willDeactivateNotification, the new window correctly opens in front of the user. (I tested this within a opened immersive space.)
Does this imply that dismissWindow is actually asynchronous, in the sense that it requires extra time to reset certain internal states before the next openWindow can be called? What is the best practice to close a window, then open a new window in front of the user's current head position?
We are developing a mixed reality app for Vision Pro using Reality Composer Pro, but we're consistently encountering a Protobuf-related crash whenever we enter the immersive space. Our Reality Composer Pro package is quite complex, with numerous objects. Could the complexity of the package be contributing to the issue, or could something else be at play? No errors are being flagged in the code or Reality Composer itself.
Here’s the error log:
[libprotobuf FATAL /Library/Caches/com.apple.xbs/Sources/REKit/ThirdParty/protobuf/src/google/protobuf/io/zero_copy_stream_impl_lite.cc:276] CHECK failed: (count) >= (0):
libc++abi: terminating due to uncaught exception of type google::protobuf::FatalException: CHECK failed: (count) >= (0):
Any insight on what might be causing this would be appreciated.
I have created two scenes, one immersive and one volumetric using Reality Composer Pro. In my test app I can view both and they render correctly.
However, I would like to add entities programmatically. I am trying this;
var body: some View {
RealityView { content in
if let scene = try? await Entity(named: "Scene", in: realityKitContentBundle) {
viewModel.rootEntity = scene
content.add(scene)
var anchorEntity = AnchorEntity(world: [0, 0, -0.5])
let sphere = MeshResource.generateSphere(radius: 2.0)
let material = SimpleMaterial(color: .red, roughness: 0.5, isMetallic: true)
let modelEntity = ModelEntity(mesh: sphere, materials: [material])
anchorEntity.addChild(modelEntity)
content.add(anchorEntity)
}
}
}
However, the sphere does not appear in the volume. I also tried it in the immersive space and it does not appear there either.
What am I missing?
I am trying to achieve an effect such that the particles of a particle system are attracted to my hand entity. The hand entity is essentially an AnchorEntity that is tracking my right hand.
let particleEmitterEntities = context.entities(matching: particleEmitterQuery, updatingSystemWhen: .rendering)
for particleEmitterEntity in particleEmitterEntities {
if var particleEmitter = particleEmitterEntity.components[ParticleEmitterComponent.self] {
particleEmitter.mainEmitter.attractionCenter = rightHandEntity.position(relativeTo: nil)
// trying to get the world space position of the hand
// I also tried relative to particleEmitterEntity
particleEmitterEntity.components[ParticleEmitterComponent.self] = particleEmitter
} else {
fatalError("Cannot find particle emitter")
}
}
The particle attraction center doesn't seem to update
Another issue I am noticing here that My particle system doesn't show the particle image a lot of times and just renders a placeholder square when I do this, when I comment this code out I get the right particle image. I believe this is due to the number of times this loop runs to update the position of the attraction center.
What is the right way to do an effect where the particles are attracted to my hand.
Im asking myself we are the limits of RealityView. For example is it possible to place an entity on postion (x=800m,y=0,z=-900m) What happens if i walk from my (0,0,0) to this point, will i see the entity then ? Does someone know where are the limits ?
I am new to the graph editor and was able to achieve some results. However, I am noticing that my graphs are getting very tangled, confusing, and hard to debug. I was wondering whether:
is it possible to define variables, to store the value of computations, and refer to them in other parts of the graph, without having to link them graphically? This would help in tidying the tangled mess I created. In the "Explore materials in Reality Composer Pro" video, I saw that it is possible to create "instances", but I am not sure if that is what I need. For example: does the shader compiler optimize them, so that there is no need to recompute each instance?
Is there any functionality to debug the graph, trying inputs and seeing what the numeric outputs would be?