🎮 UntoldArcade

UntoldArcade is the demo playground for the Untold Engine — a real, running Xcode project for every major thing the engine can do, from mixed-reality digital twins to GPU cloth you can punch a ball through.

Clone it, open a folder, hit ⌘R, and you're looking at the feature instead of reading about it.

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📺 Demos

Each demo is a standalone Xcode project with its own README, tutorial, and bundled assets — no setup beyond opening the .xcodeproj. The three Rendering Extensions (CoolSaber, CoolWater, CoolCloth) are reusable plugins — each ships its own shader library, pipelines, and render-graph passes, and can be dropped into any project.

⚔️ CoolSaber — visionOS · Rendering Extension

Lightsaber duels driven by PSVR2 Sense controllers — pull the trigger to ignite a glowing blade, then duel a friend over SharePlay with clashing sparks, haptic kicks, and synthesized saber audio. Requires a physical Vision Pro (the deferred G-buffer exceeds simulator tile memory).

open CoolSaber/Examples/CoolSaberVisionOS/CoolSaberVisionOS.xcodeproj

💧 CoolWater — visionOS · Rendering Extension

Real-time animated water with reflection/refraction and ripple simulation.

open CoolWater/Examples/CoolWaterVisionOS/CoolWaterVisionOS.xcodeproj

🧵 CoolCloth — visionOS · Rendering Extension

GPU cloth simulation (XPBD, small-steps scheme) hanging in your real room — pinch it to grab a particle, throw a ball through it, switch materials live, and let real furniture occlude it.

open CoolCloth/Examples/CoolClothVisionOS/CoolClothVisionOS.xcodeproj

🏛️ ArchvizViewer — visionOS

Load a Blender-authored architectural visualization straight into mixed reality — lights, camera, and color management carried over exactly as the artist set them up. Pinch-drag and two-hand rotate to walk the scene around your room. Reference project for the Archviz To Vision Pro tutorial.

• Async, non-blocking model loading (setEntityMeshAsync)
• Blender-authored lights/camera/color management (loadSceneAuthored)
• Vision Pro spatial picking and two-hand scene rotation

open ArchvizViewer/ArchvizViewer.xcodeproj

🛋️ BedroomTwin — visionOS

A digital twin of a bedroom: the same room model, but different parts of it behave differently. The window becomes a passthrough light portal; the lamps, door, curtains, and laptop stay individually tappable and carry live mock status data. Reference project for the Bedroom Digital Twin tutorial.

• SceneChannel splitting geometry into context / window / selectable objects by naming convention
• Light-portal + passthrough ghost rendering on the window channel
• Per-object tap selection resolved against mock digital-twin status data

open BedroomTwin/BedroomTwin.xcodeproj

🏙️ CityStreaming — visionOS

A city too big to fit in GPU memory, streamed in tile by tile as you walk through it — nearby tiles load at full detail, distant ones fall back to LOD/HLOD, and static batching updates incrementally in the background. Reference project for City Streaming On Vision Pro.

• Tiled streaming manifests (setEntityStreamScene) instead of one monolithic model
• Distance-based load/unload with LOD/HLOD fallback
• Spatial debug overlays for tile bounds, octree residency, and texture streaming tiers

open CityStreaming/CityStreaming.xcodeproj

🛠️ SceneBuilder — macOS / iOS

A declarative, SwiftUI-style syntax for building 3D scenes in code — cubes, PBR materials, and animated waves assembled without a scene editor.

open SceneBuilder/SceneBuilder.xcodeproj

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⚙️ Requirements

• Xcode 26.1 or later
• macOS 26.01+ (for macOS demos)
• iOS 26.01+ (for iOS demos)
• visionOS 26.01+ (for Vision Pro demos)
• Metal-capable GPU
• A physical Apple Vision Pro for CoolSaber (simulator can't run the deferred renderer's G-buffer)

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🚀 Getting Started

1. Clone the repo

git clone https://github.com/untoldengine/UntoldArcade.git
cd UntoldArcade

2. Open a demo project

Each demo is a standalone Xcode project. Navigate to the demo folder and open the .xcodeproj file — see the open command under each demo above.

Most demos generate their Xcode project from project.yml via XcodeGen. If you add/remove source files or change dependencies, re-run xcodegen generate inside that demo's folder before opening/building.

3. Build and run

• Select your target device (Mac, iPhone, iPad, or Vision Pro simulator)
• Press ⌘R to build and run
• SPM will automatically fetch the Untold Engine dependency on first build

🔗 Engine Dependency

Each demo project depends on the Untold Engine via Swift Package Manager (SPM). The workspace is already configured to fetch the engine from its develop branch on GitHub.

📂 Project Structure

UntoldArcade/
├── CoolSaber/           # Rendering Extension — PSVR2 lightsaber duels + SharePlay
├── CoolWater/           # Rendering Extension — real-time animated water
├── CoolCloth/           # Rendering Extension — GPU cloth simulation (XPBD)
├── ArchvizViewer/       # visionOS — Blender archviz scene in mixed reality
├── BedroomTwin/         # visionOS — digital-twin bedroom with channel-based selection
├── CityStreaming/       # visionOS — tiled city streaming with LOD/HLOD
├── SceneBuilder/        # macOS/iOS — declarative scene-building demo
└── docs/media/          # Screenshots/GIFs/video referenced by this README

Each demo folder generally follows:

<Demo>/
├── project.yml               # XcodeGen config (where used)
├── README.md                 # Demo-specific overview + what it teaches
└── Sources/<Demo>/
    ├── <Demo>App.swift        # App entry point
    ├── GameScene.swift        # Scene setup, input, per-frame logic
    └── GameData/               # Bundled models, textures, HDRs, streamed tiles

🤝 Contributing

We welcome contributions! If you'd like to:

• Add a new demo game
• Improve existing demos
• Enhance documentation

Please fork the repo, open a PR, or join discussions in the Untold Engine repo.

📜 License

This project follows the same license as Untold Engine. See the LICENSE file for details.