Implementing adjustable material
At a glance
| Item | Summary |
|---|---|
| Purpose | Update the adjustable parameters of a 3D model in visionOS. |
| App architecture | GlassApp composes WindowGroup around MainView; view-local SwiftUI state owns interaction while RealityView manages the entity graph. |
| Main patterns | SwiftUI scene composition, SwiftUI–RealityKit bridge |
| Project style | Code-light sample with 4 scanned Swift file(s) and 147 Swift line(s); resources and generated assets are excluded from those counts. |
Project structure
Source bundle/
└── Glass/
├── App/
│ └── EntryPoint.swift # GlassApp
├── Views/
│ ├── GlassView.swift # GlassView
│ └── MainView.swift # MainView
└── Extentions/
└── Entity.swift
Structure observations
- The runtime boundary is WindowGroup; the pruned tree lists only files that explain lifecycle, state, or framework integration.
- App code is compact; any explicit model, provider, or entity owner is still shown below rather than collapsed into view-local state.
Overall architecture
flowchart LR
GlassApp_1["GlassApp"]
WindowGroup_2["WindowGroup"]
MainView_3["MainView"]
RealityView_entity_graph_4["RealityView entity graph"]
RealityKit_entity_graph_5["RealityKit entity graph"]
GlassApp_1 --> WindowGroup_2
WindowGroup_2 --> MainView_3
MainView_3 --> RealityView_entity_graph_4
RealityView_entity_graph_4 --> RealityKit_entity_graph_5
Reference code
Glass/App/EntryPoint.swift:11 — the app or executable entry declares the outer scene lifecycle.
struct GlassApp: App {
var body: some Scene {
WindowGroup {
MainView()
}
}
}The diagram is a responsibility flow, not a claim that every adjacent node directly calls the next. It keeps scene ownership, shared state, RealityKit content, and framework-provider work at separate levels.
Ownership and state
classDiagram
GlassView *-- Entity : entity
Ownership evidence
Glass/Views/GlassView.swift:20 — representative stored state or the nearest verified lifecycle anchor.
struct GlassView: View {
// ...
@State var entity: Entity?
// ...
}| Owner | Object or state | Relationship | Mutation authority |
|---|---|---|---|
GlassView |
Entity as entity |
owns a SwiftUI-managed reference slot | The owning type coordinates writes |
Ownership here is deliberately narrow: @Environment and weak references are shared links, initialized @State or stored services are lifecycle ownership, and a RealityView content closure owns additions to its entity graph without making the SwiftUI view a reference-type owner.
Class and protocol design
| Type | Responsibility | Depends on or conforms to |
|---|---|---|
GlassApp (Glass/App/EntryPoint.swift:11) |
Declares app scenes and top-level dependency lifetime. | App |
MainView (Glass/Views/MainView.swift:10) |
Presents UI and forwards gestures or lifecycle events. | View |
GlassView (Glass/Views/GlassView.swift:12) |
Presents UI and forwards gestures or lifecycle events. | View |
The source defines no local substitution protocol in the reviewed boundary. Its protocol use is framework-facing (App, View, RealityKit/ARKit protocols, or platform adapters), so this document does not label the whole app protocol-oriented.
Access control
| Symbol | Access | Verified effect | Likely rationale |
|---|---|---|---|
public func updateMaterials(_ update: (inout Material) -> Void) { (Glass/Extentions/Entity.swift:13) |
public |
The declaration is available to importing modules, subject to its containing type’s visibility. | Inference: Satisfy a cross-target or framework-facing surface without implying subclassability. |
No reviewed declaration uses fileprivate, private(set), open; unmodified Swift declarations are internal.
Reference code
Glass/Extentions/Entity.swift:13 — representative visibility boundary.
public func updateMaterials(_ update: (inout Material) -> Void) {
// ...
}Logic ownership and placement
| Logic | Owning type or file | Placement rationale |
|---|---|---|
| Scene declaration and dependency lifetime | GlassApp |
The App/entry boundary determines window, volume, and immersive-space lifetime. |
| Presentation, attachments, and gestures | MainView |
SwiftUI view code forwards user intent and RealityView lifecycle events. |
Design patterns
| Pattern | Source evidence | Purpose or tradeoff |
|---|---|---|
| SwiftUI scene composition | Glass/App/EntryPoint.swift:11 |
Keeps windows, volumes, and immersive-space lifecycle visible at the app boundary. |
| SwiftUI–RealityKit bridge | Glass/Views/GlassView.swift:24 |
Builds and updates a RealityKit entity graph from SwiftUI lifecycle closures. |
Naming conventions
- Role suffixes are evidence, not decoration: App:
GlassApp; View:GlassView,MainView. - Protocols: no app-defined protocol in the reviewed source.
- Commands use verb-led methods:
updateMaterials. - Files generally match their primary type;
Views,Models,Managers,Providers,Components,Systems, andPackagesfolders describe architectural roles where present.
Architecture takeaways
- Treat
GlassAppas the owner of scene declarations, not as the owner of every RealityKit entity created later. - Keep view-local interaction in SwiftUI, but move provider sessions, playback resources, shared game state, or transport state into a stable owner when their lifetime exceeds one render pass.
- The compact source does not justify adding repository, coordinator, or protocol layers beyond the model, provider, or view boundary the sample actually declares.
Source map
| Source file | Relevant symbols |
|---|---|
Glass/App/EntryPoint.swift:11 |
GlassApp |
Glass/Views/GlassView.swift:12 |
GlassView |
Glass/Views/MainView.swift:10 |
MainView |
Glass/Extentions/Entity.swift:1 |
Feature implementation |