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"A Swift-based 3D game engine designed for simplicity and creativity on macOS and iOS."
The Untold Engine is an open-source 3D game engine under active development, designed for macOS and iOS platforms. Written in Swift and powered by Metal, its goal is to simplify game creation with a clean, intuitive API. While the engine already supports many core systems like rendering, physics, and animation, there’s still much to build and improve.
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The Untold Engine strives to be a stable, performant, and developer-friendly 3D engine that empowers creativity, removes friction, and makes game development feel effortless for Apple developers
To achieve this vision, we follow these principles:
- The engine strives to remain stable and crash-free.
- The codebase is backed by unit tests.
- We profile continuously to prevent regressions (visual and performance).
- The API must remain clear and user-friendly.
- We always think about the developer first—removing friction so they can focus on their games.
- Simple API: Focused on ease of use, even for those new to game development.
- Core Systems: Includes foundational systems for entity registration, rendering, physics, and more.
- Metal Integration: Leverages Apple’s graphics API for efficient rendering.
The Untold Engine is a work in progress, with ambitious goals to:
- Expand physics capabilities with collision detection.
- Enhance PBR rendering for more realistic visuals.
- Add new features to make game development a breeze.
- For Learners: A great way to explore game development with an engine that prioritizes simplicity.
- For Game Developers: An opportunity to contribute to an open-source project and shape its future.
- For Apple Developers: A Swift and Metal-based engine that feels at home on macOS and iOS.
The engine is far from complete, but with every iteration, it gets closer to being an amazing tool for developers. By trying it out, contributing, or sharing your feedback, you can help make the Untold Engine better for everyone.
Author: Harold Serrano
👉 Full setup instructions, guides, and API references are now maintained in our official documentation site: Untold Engine Docs
There you’ll find:
- Installation & setup
- Editor overview
- How-to guides (import assets, add models, use systems)
- API examples ⚡ If you’re new, start with the Getting Started guide.
See the open issues for a list of proposed features (and known issues).
- Top Feature Requests (Add your votes using the 👍 reaction)
- Top Bugs (Add your votes using the 👍 reaction)
- Newest Bugs
Reach out to the maintainer at one of the following places:
If you want to say thank you or/and support active development of Untold Engine:
- Add a GitHub Star to the project.
- Tweet about the Untold Engine.
- Write interesting articles about the project on Dev.to, Medium or your personal blog.
Together, we can make Untold Engine better!
We welcome contributions to the Untold Engine! Here’s how you can help:
- Fix Bugs: Review open issues labeled help wanted.
- Improve Features: Enhance existing systems, such as adding collision detection to the physics system.
- Create Tutorials: Write how-to guides or share examples to help other developers.
- Expand the Engine: Suggest and implement new features like AI systems or advanced shaders.
See the Contribution Guidelines for details.
This project is licensed under the LGPL v3.0.
- Developing a Game: You can use the Untold Engine to build your game without needing to open source your game’s code.
- Modifying the Engine: If you make changes to the engine itself, those changes must be open-sourced under the LGPL v3.0.
- Stronger Protections: LGPL v3.0 adds explicit patent protection and compatibility with modern licenses like Apache-2.0 (used by OpenUSD).
| You want to… | Allowed? | Obligations |
|---|---|---|
| Build a game with Untold Engine | ✅ Yes | No need to open source your game’s code |
| Modify Untold Engine internals | ✅ Yes | Must share modifications under LGPL v3.0 |
| Distribute the Untold Engine | ✅ Yes | Keep the LGPL license intact |
| Use for commercial projects | ✅ Yes | No royalties or fees |
| Combine with Apache-2.0 libs (e.g. OpenUSD) | ✅ Yes | Fully compatible under LGPL v3.0 |
For more details, see the full license text here.
💡 Our philosophy: You’re free to build with Untold Engine however you like — but if you improve the engine itself, those improvements should be shared back so the whole community benefits.
To keep communication clear and accessible for everyone:
- 💡 Use GitHub Discussions for feature proposals, ideas, or general questions.
- 🐞 Use GitHub Issues for bugs or concrete tasks that need tracking.
This way, conversations stay organized, visible to the community, and future contributors can benefit from past discussions.