Incorporating real-world surroundings in an immersive experience
At a glance
| Item | Summary |
|---|---|
| Purpose | Create an immersive experience by making your app’s content respond to the local shape of the world. |
| App architecture | A Swift sample with the source-visible chain SceneReconstructionExampleApp → EntityModel → ARKit / RealityKit APIs. |
| Main patterns | No named application pattern supported by the extracted structure |
| Project style | 4 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries. |
| Execution model | Source-visible boundaries: await suspension point, @MainActor; none alone proves a background thread. |
| State/event model | Source-visible mechanisms: SwiftUI state property wrapper, @Observable. |
| Key frameworks/packages | ARKit, RealityKit, SwiftUI, OSLog; these are source dependencies, not architecture labels. |
Project structure
Source bundle/
├── SceneReconstructionExample/
│ ├── SceneReconstructionExampleApp.swift
│ ├── EntityModel.swift
│ ├── CubeMeshInteraction.swift
│ ├── Extensions.swift
│ └── Info.plist
├── Configuration/
│ └── SampleCode.xcconfig
└── SceneReconstructionExample.xcodeproj/
├── .xcodesamplecode.plist
└── project.pbxproj
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 3 source declaration(s).
Overall architecture
flowchart LR
N1["SceneReconstructionExampleApp"]
N2["EntityModel"]
N3["ARKit / RealityKit APIs"]
N1 --> N2
N2 --> N3
Reference code
SceneReconstructionExample/SceneReconstructionExampleApp.swift:12 — architecture anchor
@main
struct SceneReconstructionExampleApp: App {
@State private var model = EntityModel()
var body: some Scene {
ImmersiveSpace(id: cubeMeshInteractionID) {
CubeMeshInteraction()
.environment(model)
}
}
}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 visionOS.
Ownership and state
classDiagram
SceneReconstructionExampleApp *-- EntityModel : model
SceneReconstructionExampleApp *-- Logger : logger
EntityModel *-- ARKitSession : session
EntityModel *-- HandTrackingProvider : handTracking
Ownership evidence
SceneReconstructionExample/SceneReconstructionExampleApp.swift:14 — stored dependency or nearest verified ownership anchor
@main
struct SceneReconstructionExampleApp: App {
@State private var model = EntityModel()
// ...
}| Owner | Object or state | Relationship | Mutation authority |
|---|---|---|---|
SceneReconstructionExampleApp |
EntityModel (model) |
owns wrapper-managed state | Owning lexical scope |
SceneReconstructionExampleApp |
Logger (logger) |
creates and retains | Initialized by the owner; the binding is immutable |
EntityModel |
ARKitSession (session) |
creates and retains | Initialized by the owner; the binding is immutable |
EntityModel |
HandTrackingProvider (handTracking) |
creates and retains | Initialized by the owner; the binding is immutable |
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.
Concurrency, scheduling, and thread safety
Evidence limit: actor isolation, async/await, or Task creation does not by itself prove background-thread execution; Sendable conformance alone does not prove thread-safe mutation.
| Concern | Source mechanism | Verified placement or handoff | Evidence |
|---|---|---|---|
| Suspension boundary | await suspension point |
The source declares or crosses an asynchronous boundary; it does not by itself establish background execution. | SceneReconstructionExample/CubeMeshInteraction.swift:46 |
| Main isolation | @MainActor |
The cited annotation marks its attached declaration or closure as main-actor isolated. | SceneReconstructionExample/EntityModel.swift:13 |
@MainActor/MainActor.run, DispatchQueue.main, and RunLoop.main are reported as distinct isolation, queue, and event-loop mechanisms. A plain Task is kept separate from Task.detached; neither is labeled as a background thread.
Reference code
SceneReconstructionExample/CubeMeshInteraction.swift:46 — representative execution boundary
struct CubeMeshInteraction: View {
// ...
try await model.session.run([model.sceneReconstruction, model.handTracking])
// ...
}State propagation, frameworks, and dependencies
Evidence limit: an import proves a source-level compilation dependency at the cited line; it does not prove runtime use, architectural adoption, or whether a Swift package is a direct application dependency.
| Category | Mechanism or module | Verified role | Evidence |
|---|---|---|---|
| State propagation | SwiftUI state property wrapper |
A SwiftUI property wrapper supplies or observes UI state. | SceneReconstructionExample/CubeMeshInteraction.swift:18 |
| State propagation | @Observable |
Observation macro publishes source-visible changes. | SceneReconstructionExample/EntityModel.swift:12 |
| Source import | ARKit |
The cited file imports this module; runtime use and architectural role are not inferred. | SceneReconstructionExample/CubeMeshInteraction.swift:8 |
| Source import | RealityKit |
The cited file imports this module; runtime use and architectural role are not inferred. | SceneReconstructionExample/CubeMeshInteraction.swift:10 |
| Source import | SwiftUI |
The cited file imports this module; runtime use and architectural role are not inferred. | SceneReconstructionExample/CubeMeshInteraction.swift:9 |
| Source import | OSLog |
The cited file imports this module; runtime use and architectural role are not inferred. | SceneReconstructionExample/SceneReconstructionExampleApp.swift:8 |
receive(on:) describes downstream delivery scheduling, while subscribe(on:) describes upstream subscription/request/cancel scheduling. An import Combine alone establishes neither behavior nor a Store, reducer, Redux, or other application architecture.
Class and protocol design
SceneReconstructionExample/SceneReconstructionExampleApp.swift:13 — representative type boundary
@main
struct SceneReconstructionExampleApp: App {
@State private var model = EntityModel()
// ...
}| Type | Responsibility | Depends on or conforms to |
|---|---|---|
SceneReconstructionExampleApp |
Application entry and top-level composition | App |
EntityModel |
Feature data or observable state | Concrete collaborators/imported frameworks |
CubeMeshInteraction |
Represents a feature value or composable behavior | View |
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 |
|---|---|---|---|
meshEntities (SceneReconstructionExample/EntityModel.swift:21) |
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. |
fingerEntities (SceneReconstructionExample/EntityModel.swift:22) |
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. |
model (SceneReconstructionExample/SceneReconstructionExampleApp.swift:14) |
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
SceneReconstructionExample/EntityModel.swift:21 — representative boundary
@Observable
@MainActor
class EntityModel {
// ...
private var meshEntities = [UUID: ModelEntity]()
// ...
}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 | SceneReconstructionExampleApp |
The source’s App suffix makes this role explicit. |
| Feature data or observable state | EntityModel |
The source’s Model suffix makes this role explicit. |
Design patterns
| Pattern | Source evidence | Purpose or tradeoff |
|---|---|---|
| No named application pattern | SceneReconstructionExample/SceneReconstructionExampleApp.swift:12 |
The verified source directly composes concrete framework types; this document avoids forcing a pattern name. |
Naming conventions
- Types: App: SceneReconstructionExampleApp; Model: EntityModel.
- Protocols: no local protocol declaration in the scanned source.
- Methods:
setupContentEntity,processHandUpdates,processReconstructionUpdates,monitorSessionEvents,addCube,createFingertip. - Files:
SceneReconstructionExample/SceneReconstructionExampleApp.swift,SceneReconstructionExample/EntityModel.swift,SceneReconstructionExample/CubeMeshInteraction.swift.
Architecture takeaways
SceneReconstructionExampleAppis the main source-visible entry or composition anchor for this sample.- Framework work reaches ARKit, RealityKit, SwiftUI 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 |
|---|---|
SceneReconstructionExample/SceneReconstructionExampleApp.swift |
Cited implementation, SceneReconstructionExampleApp, OSLog |
SceneReconstructionExample/EntityModel.swift |
Cited implementation, @MainActor, @Observable, EntityModel |
SceneReconstructionExample/CubeMeshInteraction.swift |
await suspension point, SwiftUI state property wrapper, ARKit, RealityKit, SwiftUI, CubeMeshInteraction |
SceneReconstructionExample/Extensions.swift |
func |