Visualizing and interacting with a reconstructed scene
At a glance
| Item | Summary |
|---|---|
| Purpose | Estimate the shape of the physical environment using a polygonal mesh. |
| App architecture | A Swift sample with the source-visible chain AppDelegate → ViewController → ARKit APIs. |
| Main patterns | View-controller organization, Delegate or data-source callbacks |
| Project style | 5 scanned source file(s) across Swift, organized around ranked entry, type, and file boundaries. |
Project structure
Source bundle/
├── VisualizingSceneSemantics/
│ ├── AppDelegate.swift
│ ├── ViewController.swift
│ ├── RoundedButton.swift
│ ├── Extensions.swift
│ ├── ViewController+CoachingOverlay.swift
│ ├── Base.lproj/
│ │ ├── LaunchScreen.storyboard
│ │ └── Main.storyboard
│ └── Info.plist
├── Configuration/
│ └── SampleCode.xcconfig
└── VisualizingSceneSemantics.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 6 project/configuration file(s) and 3 source declaration(s).
Overall architecture
flowchart LR
N1["AppDelegate"]
N2["ViewController"]
N3["ARKit APIs"]
N1 --> N2
N2 --> N3
Reference code
VisualizingSceneSemantics/AppDelegate.swift:11 — architecture anchor
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
// ...
}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
AppDelegate o-- UIWindow : window
ViewController o-- ARView : arView
ViewController o-- UIButton : hideMeshButton
ViewController o-- UIButton : resetButton
Ownership evidence
VisualizingSceneSemantics/AppDelegate.swift:14 — stored dependency or nearest verified ownership anchor
@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
// ...
var window: UIWindow?
// ...
}| Owner | Object or state | Relationship | Mutation authority |
|---|---|---|---|
AppDelegate |
UIWindow (window) |
stores or receives | App/module collaborators |
ViewController |
ARView (arView) |
stores or receives | App/module collaborators |
ViewController |
UIButton (hideMeshButton) |
holds a non-owning reference | The referenced object’s lifecycle is owned elsewhere |
ViewController |
UIButton (resetButton) |
holds a non-owning reference | The referenced object’s lifecycle is owned elsewhere |
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
VisualizingSceneSemantics/AppDelegate.swift:12 — representative type boundary
class AppDelegate: UIResponder, UIApplicationDelegate {
// ...
}| Type | Responsibility | Depends on or conforms to |
|---|---|---|
AppDelegate |
Receives callback-driven events | UIResponder, UIApplicationDelegate |
ViewController |
View lifecycle, callbacks, and feature coordination | UIViewController, ARSessionDelegate |
RoundedButton |
Owns feature behavior and collaborator lifecycle | UIButton |
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 |
|---|---|---|---|
AppDelegate (VisualizingSceneSemantics/AppDelegate.swift:12) |
implicit internal |
No explicit modifier means the Swift declaration is internal to the module. | Inference: app-target collaboration needs no exported library surface. |
ViewController (VisualizingSceneSemantics/ViewController.swift:11) |
implicit internal |
No explicit modifier means the Swift declaration is internal to the module. | Inference: app-target collaboration needs no exported library surface. |
RoundedButton (VisualizingSceneSemantics/RoundedButton.swift:11) |
implicit internal |
No explicit modifier means the Swift declaration is internal to the module. | Inference: app-target collaboration needs no exported library surface. |
Reference code
VisualizingSceneSemantics/AppDelegate.swift:12 — representative boundary
class AppDelegate: UIResponder, UIApplicationDelegate {
// ...
}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 |
|---|---|---|
| View lifecycle, callbacks, and feature coordination | ViewController |
The source’s Controller suffix makes this role explicit. |
| Receives callback-driven events | AppDelegate |
The source’s Delegate suffix makes this role explicit. |
Design patterns
| Pattern | Source evidence | Purpose or tradeoff |
|---|---|---|
| View-controller organization | VisualizingSceneSemantics/ViewController.swift:11 |
A controller is the verified coordination boundary; this is MVC-style only where a separate model is present. |
| Delegate or data-source callbacks | VisualizingSceneSemantics/AppDelegate.swift:12 |
Callback protocols invert event delivery back into the sample’s owner. |
Naming conventions
- Types: Controller: ViewController; Delegate: AppDelegate.
- Protocols: no local protocol declaration in the scanned source.
- Methods:
application,viewDidLoad,viewDidAppear,handleTap,resetButtonPressed,toggleMeshButtonPressed,togglePlaneDetectionButtonPressed,nearbyFaceWithClassification. - Files:
VisualizingSceneSemantics/AppDelegate.swift,VisualizingSceneSemantics/ViewController.swift,VisualizingSceneSemantics/RoundedButton.swift.
Architecture takeaways
AppDelegateis the main source-visible entry or composition anchor for this sample.- Framework work reaches ARKit, UIKit, RealityKit 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 |
|---|---|
VisualizingSceneSemantics/AppDelegate.swift |
AppDelegate |
VisualizingSceneSemantics/ViewController.swift |
ViewController |
VisualizingSceneSemantics/RoundedButton.swift |
RoundedButton |
VisualizingSceneSemantics/Extensions.swift |
Feature implementation |
VisualizingSceneSemantics/ViewController+CoachingOverlay.swift |
Feature implementation |