Displaying a point cloud using scene depth

At a glance

Project structure

Source bundle/
├── pointCloudSample/
│   ├── PointCloudDepthSample.swift
│   ├── ARDataProvider.swift
│   ├── ARReceiver.swift
│   ├── MetalPointCloud.swift
│   ├── MetalViewSample.swift
│   ├── MetalTextureViewCoefs.swift
│   ├── MetalTextureViewConfidence.swift
│   ├── MetalTextureViewDepth.swift
│   ├── EnvironmentVariables.swift
│   └── shaders.metal
├── Configuration/
│   └── SampleCode.xcconfig
└── pointCloudSample.xcodeproj/
    └── .xcodesamplecode.plist

Structure observations

• Architecturally prominent files are ranked from entry points and role-named declarations; resource-only paths are omitted.
• Primary languages: Metal, Swift.
• The verified tree contains 4 project/configuration file(s) and 18 source declaration(s).

Overall architecture

flowchart LR
    N1["PointCloudDepthSample"]
    N2["MetalDepthView"]
    N3["MTKCoordinator"]
    N4["ARProvider"]
    N5["ARKit APIs"]
    N1 --> N2
    N2 --> N3
    N3 --> N4
    N4 --> N5

Reference code

pointCloudSample/PointCloudDepthSample.swift:9 — architecture anchor

@main
struct PointCloudDepthSample: App {
    var body: some Scene {
        WindowGroup {
            MetalDepthView()
        }
    }
}

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

classDiagram
    MetalTextureContent o-- MTLTexture : texture
    ARProvider *-- Float : guidedFilterEpsilon
    ARProvider *-- ARReceiver : arReceiver
    ARProvider o-- ARData : lastArData

Ownership evidence

pointCloudSample/ARDataProvider.swift:17 — stored dependency or nearest verified ownership anchor

final class MetalTextureContent {
    var texture: MTLTexture?
}

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.

No source-visible execution, scheduling, or synchronization boundary was found in the indexed source.

@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.

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.

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

pointCloudSample/ARReceiver.swift:14 — representative type boundary

protocol ARDataReceiver: AnyObject {
    func onNewARData(arData: ARData)
}

The source explicitly defines local protocol relationships: ARProvider → ARDataReceiver.

Access control

Reference code

pointCloudSample/ARDataProvider.swift:76 — representative boundary

    public var isToUpsampleDepth: Bool = false {
        didSet {
            processLastArData()
        }
    }

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

Design patterns

Naming conventions

• Types: Coordinator: MTKCoordinator; Provider: ARProvider; View: MetalDepthView.
• Protocols: ARDataReceiver.
• Methods: texture, createTexture, start, pause, onNewARData, processLastArData, session, makePerspectiveMatrixProjection.
• Files: pointCloudSample/PointCloudDepthSample.swift, pointCloudSample/ARReceiver.swift, pointCloudSample/MetalPointCloud.swift, pointCloudSample/MetalTextureViewCoefs.swift, pointCloudSample/MetalTextureViewConfidence.swift, pointCloudSample/MetalTextureViewDepth.swift.

Architecture takeaways

• PointCloudDepthSample is the main source-visible entry or composition anchor for this sample.
• Framework work reaches SwiftUI, Metal, MetalKit, 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.
• Local protocol relationships provide an explicit substitution boundary.

Source map

• Official Apple documentation