This week, I developed a small multiplatform RealityKit project. I also created a demo scene in Reality Composer Pro. Afterward, I imported the local package into the project. Running the project on macOS works perfectly. However, when I tried to run it on my iPhone, I encountered a permission error indicating that it couldn’t read the package. This seems unusual to me because I assumed that the dependency is bundled into the binary file. In an attempt to resolve the issue, I pushed the RCP package to GitHub, hoping it would work. Fortunately, everything compiles successfully now, but the loading time is significantly long, and the animations don’t play on tap gestures.
Could someone please help me identify the root cause of this problem?
RealityKit
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I've loaded a ShaderGraphMaterial from a RealityKit content bundle and I'm attempting to access the initial values of its parameters using getParameter(handle:), but this method appears to always return nil:
let shaderGraphMaterial = try await ShaderGraphMaterial(named: "MyMaterial", from: "MyFile")
let namedParameterValue = shaderGraphMaterial.getParameter(name: "myParameter")
// This prints the value of the `myParameter` parameter, as expected.
print("namedParameterValue = \(namedParameterValue)")
let handle = ShaderGraphMaterial.parameterHandle(name: "myParameter")
let handleParameterValue = shaderGraphMaterial.getParameter(handle: handle)
// Expected behavior: prints the value of the `myParameter` parameter, as above.
// Observed behavior: prints `nil`.
print("handleParameterValue = \(handleParameterValue)")
Is this expected behavior?
Based on the documentation at https://developer.apple.com/documentation/realitykit/shadergraphmaterial/getparameter(handle:) I'd expect getParameter(handle:) to return the value of the parameter, just as getParameter(name:) does.
I've tested this on iOS 18.5 and iOS 26.0 beta 2.
Assuming this getParameter(handle:) works as designed, is the following ShaderGraphMaterial extension an appropriate workaround, or can you recommend a better approach?
Thank you.
public extension ShaderGraphMaterial {
/// Reassigns the values of all named material parameters using the handle-based API.
///
/// This works around an issue where, at least as of RealityKit 26.0 beta 2 and
/// earlier, `getParameter(handle:)` will always return `nil` when used to read the
/// initial value of a shader graph material parameter read using
/// `ShaderGraphMaterial(named:from:in:)`, whereas `getParameter(name:)` will work
/// as expected.
private mutating func copyNamedParametersToHandles() {
for parameterName in self.parameterNames {
if let value = self.getParameter(name: parameterName) {
let handle = ShaderGraphMaterial.parameterHandle(name: parameterName)
do {
try self.setParameter(handle: handle, value: value)
} catch {
assertionFailure("Cannot set parameter value")
}
}
}
}
}
Topic:
Graphics & Games
SubTopic:
RealityKit
Tags:
RealityKit
Reality Composer Pro
Shader Graph Editor
visionOS
Is there a way to permanently disable PHASE SDK logging? It seems to be a lot chattier than Apple's other SDKs.
While developing a RealityKit app that uses AudioPlaybackController, I must manually hide the PHASE SDK log output several times each day so I can see my app's log messages.
Thank you.
Hi,
we've been through the Explore Object Tracking for visionOS and worked through the sample code ExploringObjectTrackingWithARKit.
What we'd really like to see is Object Tracking for iOS using devices with either LiDAR or the TrueDepth/RGB cameras.
Has anyone had success with MeshInstancesComponent? I tried to follow the sample code from What's New in RealityKit but it wouldn't compile. I was able to use one of the init overloads to get it to compile, but using it crashes both my device and the simulator. Even with one instance.
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.
So I am exporting a .usdc file from blender that already has some morph animations. The animations play well in blender but when I export I cannot seem to play them in RealityKit or RCP.
Entity.availableAnimations is an empty array.
Not of the child objects in the entity hierarchy has an animation library component with it.
Maybe I am exporting it wrong but I tried multiple combinations but doesn't seem to work.
Here are my export settings in blender
The original file I purchased is an FBX file that has the animation but when I try to directly get it in RealityConverter it doesn't seem to play animations.
Topic:
Spatial Computing
SubTopic:
General
Tags:
Reality Converter
RealityKit
Reality Composer Pro
visionOS
I need a MeshResource from ModelEntity to generate a box collider, but ModelEntity fails to load USDZ files from the Reality Composer Pro (RCP) bundle.
This code works for loading an Entity:
// Successfully loads as generic Entity
previewEntity = try await Entity(named: fileName, in: realityKitContentBundle)
But this fails when trying to load as ModelEntity:
// Fails to load as ModelEntity
modelEntity = try await ModelEntity(named: fileName, in: realityKitContentBundle)
I found this thread mentioning:
"You'll likely go from USDZ to Entity which contains a MeshResource when you load/init the USDZ file."
But it doesn't explain how to actually extract the MeshResource. Could anyone advise:
How to properly load USDZ files as ModelEntity from RCP bundles?
How to extract MeshResource from a successfully loaded Entity?
Alternative approaches to generate box colliders if direct extraction isn't possible?
Sample code for extraction or workarounds would be greatly appreciated!
I'm using a class with tangents to render on RealityKit for VisionOS but in Vision26 it cause a crash on App and there not documentation how implement cp_drawable_compute_projection I have tried a few options but without success. Could you help me to implement it ?
The part of code is:
return drawable.views.map { view in
let userViewpointMatrix = (simdDeviceAnchor * view.transform).inverse
let projectionMatrix = ProjectiveTransform3D(
leftTangent: Double(view.tangents[0]),
rightTangent: Double(view.tangents[1]),
topTangent: Double(view.tangents[2]),
bottomTangent: Double(view.tangents[3]),
nearZ: Double(drawable.depthRange.y),
farZ: Double(drawable.depthRange.x),
reverseZ: true
)
let screenSize = SIMD2(x: Int(view.textureMap.viewport.width),
y: Int(view.textureMap.viewport.height))
return ModelRendererViewportDescriptor(viewport: view.textureMap.viewport,
projectionMatrix: .init(projectionMatrix),
viewMatrix: userViewpointMatrix * translationMatrix * rotationMatrix * scalingMatrix * commonUpCalibration,
screenSize: screenSize)
}
I want the effect of the model to be similar to the HoverEffect effect, but not by staring with the eyes. Instead, by clicking a button elsewhere, the corresponding model will appear highlighted,How can it be achieved
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?
Hi Nathaniel,
I spoke with you yesterday in the WWDC lab. Thanks for chatting with me! Is it possible to get a link to a doc that has some key metrics I'd find in a RealityKit trace so I know if that metric is exceeding limits and probably causing a problem? Right now, I just see numbers and have no idea if a metric is high or low :). This is specifically for a VisionOS app.
Thanks,
Bob
Hello,
I'm working on a visionOS project that uses Reality Composer Pro, and we are managing our project files with Git.
We've noticed that simply opening and closing the Reality Composer Pro application consistently generates changes in the following files, even when no explicit modifications have been made by the developer:
{ProjectName}/Packages/RealityKitContent/Package.realitycomposerpro/PluginData/*******/ShaderGraphEditorPluginID/ShaderGraphEditorPluginID
{ProjectName}/Packages/RealityKitContent/Package.realitycomposerpro/WorkspaceData/SceneMetadataList.json
Could you please clarify the purpose of these files? Why do they appear as modified when no direct changes are made from our end?
More importantly, is it safe to add these files to our .gitignore to prevent them from being tracked by Git? We are concerned that ignoring these files might lead to unexpected issues or inconsistencies when other team members pull the latest changes, especially if these files contain critical project metadata or state that needs to be synchronized.
Any insights or recommended best practices for managing Reality Composer Pro projects with Git would be greatly appreciated.
Thank you for your time and assistance.
Topic:
Spatial Computing
SubTopic:
Reality Composer Pro
Tags:
Reality Composer
RealityKit
Reality Composer Pro
I'm looking to create an effect on iOS that tracks the user's face position with ARKit and shifts nearer/more prominent geometry in the scene around while more "distant" geometry stays fixed to the XY plane - making it look like the geometry on screen "sticks out"
I've managed to implement most of this successfully, but it's not perfect when using PerspectiveCameraComponent in RealityKit because as I shift the camera (and change its field of view based on the user's distance) the backplane changes its orientation (it's always orthogonal to camera's direction).
I've tried adopting ProjectiveTransformCameraComponent instead. The idea is that the camera shifts around the scene, mirroring the user's head's position, looking at (0,0,0) and the back plane is adjusted to be parallel with the X,Y plane (animation replicated in Blender below).
However, I can't manage to set up ProjectiveTransformCameraComponent with an appropriate matrix or update its transform property in a RealityKit System correctly.
I also tried setting many simpler projection matrices as described in a number of guides on camera projection matrices on the internet and all I get is a blank view.
Does anyone have some guidance on what the projection matrix that ProjectiveTransformCameraComponent expects is meant to look like or how I would go about accomplishing my goal?
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.
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.
Hi,
since iOS 18 UnlitMaterial and ShaderGraphMaterial have the option to disable tone mapping, e.g via https://developer.apple.com/documentation/realitykit/unlitmaterial/init(applypostprocesstonemap:)
Is it possible to do the same for CustomMaterial? I tried initializing a CustomMaterial based on an UnlitMaterial where tone mapping is disabled, like so:
let unlitMat = UnlitMaterial(applyPostProcessToneMap: false)
let customMaterial = try CustomMaterial(
from: unlitMat,
surfaceShader: surfaceShader,
geometryModifier: geometryModifier
)
but that does not seem to work. The colors of my texture still look altered in comparison to a plain UnlitMaterial or a ShaderGraphMaterial where its disabled.
Any hints? Thank you!
Had anyone experienced convexCast causing a crash and what might be behind it?
Here's the call stack:
At the moment the map kit APls only support non-volumetric maps (i.e. in a window or in a volume, but on a 2D surface).
Is support for 3D volumetric maps in VisionOS in the works? And if so when can we expect it to be available?