Happy Beam

At a glance

Project structure

Source bundle/
├── HappyBeam/HappyBeamApp.swift  # HappyBeamApp, HeartGestureModelContainer
├── HappyBeam/GameModel.swift  # GameModel, InputKind
├── HappyBeam/Gameplay/HeartGestureModel.swift  # HeartGestureModel, HandsUpdates
├── HappyBeam/Gameplay/Multiplayer.swift  # HeartProjection, BeamMessage, ScoreMessage
├── HappyBeam/Views/HappyBeam.swift  # HappyBeam, GameScreen
├── HappyBeam/HappyBeamSpace.swift  # HappyBeamSpace, BeamType
├── HappyBeam/Gameplay/Clouds.swift  # Cloud, CloudAnimations, CloudSpawnParameters
├── Packages/HappyBeamAssets/Sources/HappyBeamAssets/HappyBeamAssets.swift
└── Packages/HappyBeamAssets/Package.realitycomposerpro/ProjectData/main.json  # authored RealityKit content

Structure observations

• The runtime boundary is WindowGroup + ImmersiveSpace; the pruned tree lists only files that explain lifecycle, state, or framework integration.
• App code is split into role-named views, models, managers, providers, components, or systems.
• Authored .reality or Reality Composer Pro content is a real implementation boundary; Swift loads or drives it rather than reproducing its entity graph.

Overall architecture

flowchart LR
    HappyBeamApp_1["HappyBeamApp"]
    WindowGroup___ImmersiveSpace_2["WindowGroup + ImmersiveSpace"]
    HappyBeam_3["HappyBeam"]
    GameModel_4["GameModel"]
    RealityView_entity_graph_5["RealityView entity graph"]
    GroupActivities_session_6["GroupActivities session"]
    HappyBeamApp_1 --> WindowGroup___ImmersiveSpace_2
    WindowGroup___ImmersiveSpace_2 --> HappyBeam_3
    HappyBeam_3 --> GameModel_4
    GameModel_4 --> RealityView_entity_graph_5
    RealityView_entity_graph_5 --> GroupActivities_session_6

Reference code

HappyBeam/HappyBeamApp.swift:13 — the app or executable entry declares the outer scene lifecycle.

struct HappyBeamApp: App {
    // ...
}

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
    HappyBeamApp *-- GameModel : gameModel
    HappyBeamApp *-- ImmersionStyle : immersionState
    HeartGestureModel *-- ARKitSession : session
    HappyBeam *-- GroupSession : session

Ownership evidence

HappyBeam/HappyBeamApp.swift:14 — representative stored state or the nearest verified lifecycle anchor.

    @State private var gameModel = GameModel()

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

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

No reviewed declaration uses fileprivate, open; unmodified Swift declarations are internal.

Reference code

HappyBeam/HappyBeamApp.swift:41 — representative visibility boundary.

    private(set) static var heartGestureModel = HeartGestureModel()

Logic ownership and placement

Design patterns

Naming conventions

• Role suffixes are evidence, not decoration: App: HappyBeamApp; Model: GameModel, HeartGestureModel.
• Protocols: no app-defined protocol in the reviewed source.
• Commands use verb-led methods: clear, reset, generateCloudMovementAnimations, start, publishHandTrackingUpdates, monitorSessionEvents, computeTransformOfUserPerformedHeartGesture, startSession.
• Files generally match their primary type; Views, Models, Managers, Providers, Components, Systems, and Packages folders describe architectural roles where present.

Architecture takeaways

• Treat HappyBeamApp as 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.
• Run ARKit providers for the scene lifetime and consume their asynchronous updates in cancellable tasks; map anchors to entities at the boundary.
• Model immersive-space open, transition, and close states explicitly so windows and immersive content cannot drift apart.

Source map

• Official Apple documentation