Sample CodevisionOSReviewed 2026-07-21View on Apple Developer

Building local experiences with room tracking

At a glance

Item Summary
Purpose Use room tracking in visionOS to provide custom interactions with physical spaces.
App architecture A Swift sample with the source-visible chain ARKitRoomTrackingAppContentViewARKit APIs.
Main patterns Actor-isolated state
Project style 5 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries.

Project structure

Source bundle/
├── ARKitRoomTracking/
│   ├── ARKitRoomTrackingApp.swift
│   ├── ContentView.swift
│   ├── WorldAndRoomView.swift
│   ├── AppState.swift
│   ├── Extensions.swift
│   └── Info.plist
├── ARKitRoomTracking.xcodeproj/
│   ├── .xcodesamplecode.plist
│   └── project.pbxproj
└── Configuration/
    └── SampleCode.xcconfig

Structure observations

  • Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
  • Primary languages: Swift.
  • The verified tree contains 4 project/configuration file(s) and 6 source declaration(s).

Overall architecture

Reference code

ARKitRoomTracking/ARKitRoomTrackingApp.swift:13 — architecture anchor

@main
@MainActor
struct ARKitRoomTrackingApp: App {
    // ...
}

Interpretation

The arrows summarize the source-visible entry, role-named types or folders, and framework direction; when nodes come from structural folders, the sequence is a high-level interpretation rather than proof that every adjacent node calls the next. Ownership is claimed only where the next section cites a stored property or assignment. The diagram is intentionally limited to the dominant path into ARKit.

Ownership and state

Ownership evidence

ARKitRoomTracking/ARKitRoomTrackingApp.swift:17 — stored dependency or nearest verified ownership anchor

@main
@MainActor
struct ARKitRoomTrackingApp: App {
    // ...
    @State private var appState = AppState()
    // ...
}
Owner Object or state Relationship Mutation authority
ARKitRoomTrackingApp AppState (appState) owns wrapper-managed state Owning lexical scope
ARKitRoomTrackingApp Logger (logger) creates and retains Initialized by the owner; the binding is immutable
WorldAndRoomView Entity (previewSphere) owns wrapper-managed state App/module collaborators
WorldAndRoomView Task (updateFacingWallTask) owns wrapper-managed state Owning lexical scope

Composition arrows indicate a source-visible construction expression or locally owned value state; aggregation means the owner stores or receives a dependency without proving exclusive lifetime ownership.

Class and protocol design

ARKitRoomTracking/ARKitRoomTrackingApp.swift:15 — representative type boundary

struct ARKitRoomTrackingApp: App {
    // ...
}
Type Responsibility Depends on or conforms to
ARKitRoomTrackingApp Application entry and top-level composition App
ContentView User-interface presentation and input forwarding View
WorldAndRoomView User-interface presentation and input forwarding View
AppState Represents mutable feature state Concrete collaborators/imported frameworks
VisualizationState Represents mutable feature state Concrete collaborators/imported frameworks
ErrorState Represents mutable feature state Equatable

No local protocol conformance is claimed as protocol-oriented design; external framework conformances are listed only as dependencies.

Access control

Symbol Access Verified effect Likely rationale
appState (ARKitRoomTracking/ARKitRoomTrackingApp.swift:17) private Use is restricted to the lexical declaration and same-file extensions allowed by Swift. Inference: keep state mutation or dependency lifetime inside the owning implementation.
session (ARKitRoomTracking/AppState.swift:39) private Use is restricted to the lexical declaration and same-file extensions allowed by Swift. Inference: keep state mutation or dependency lifetime inside the owning implementation.
worldTracking (ARKitRoomTracking/AppState.swift:40) private Use is restricted to the lexical declaration and same-file extensions allowed by Swift. Inference: keep state mutation or dependency lifetime inside the owning implementation.
roomTracking (ARKitRoomTracking/AppState.swift:41) private Use is restricted to the lexical declaration and same-file extensions allowed by Swift. Inference: keep state mutation or dependency lifetime inside the owning implementation.

Reference code

ARKitRoomTracking/ARKitRoomTrackingApp.swift:17 — representative boundary

@main
@MainActor
struct ARKitRoomTrackingApp: App {
    // ...
}

Swift declarations without a modifier are internal; explicit private, fileprivate, private(set), public, or open entries above are interpreted by language semantics. Objective-C/C samples instead rely on header and implementation boundaries, which are not equivalent to Swift lexical privacy.

Logic ownership and placement

Logic Owning type or file Placement rationale
Application entry and top-level composition ARKitRoomTrackingApp The source’s App suffix makes this role explicit.
User-interface presentation and input forwarding ContentView, WorldAndRoomView The source’s View suffix makes this role explicit.

Design patterns

Pattern Source evidence Purpose or tradeoff
Actor-isolated state ARKitRoomTracking/ARKitRoomTrackingApp.swift:14 Actor annotations make the concurrency ownership boundary explicit.

Naming conventions

  • Types: App: ARKitRoomTrackingApp; View: ContentView, WorldAndRoomView.
  • Protocols: no local protocol declaration in the scanned source.
  • Methods: createPreviewSphere, run, setupContentEntity, areAllDataProvidersAuthorized, runSession, isSphereInCurrentRoom, updateSphereState, getNearestWall.
  • Files: ARKitRoomTracking/ARKitRoomTrackingApp.swift, ARKitRoomTracking/ContentView.swift, ARKitRoomTracking/WorldAndRoomView.swift, ARKitRoomTracking/AppState.swift.

Architecture takeaways

  • ARKitRoomTrackingApp is the main source-visible entry or composition anchor for this sample.
  • Framework work reaches RealityKit, SwiftUI, ARKit through a deliberately small high-level chain; the detailed API graph remains inside the cited implementation files.
  • Stored-property evidence identifies lifecycle collaboration; it does not by itself prove exclusive object ownership.
  • Access-control conclusions separate verified language visibility from the likely design rationale.
  • The source does not justify labeling the design protocol-oriented.

Source map

Source file Relevant symbols
ARKitRoomTracking/ARKitRoomTrackingApp.swift ARKitRoomTrackingApp
ARKitRoomTracking/ContentView.swift ContentView
ARKitRoomTracking/WorldAndRoomView.swift WorldAndRoomView
ARKitRoomTracking/AppState.swift AppState, VisualizationState, ErrorState
ARKitRoomTracking/Extensions.swift Feature implementation