# OpenTS2: an open-source reimplementation of The Sims 2 in Unity

> Reimplements The Sims 2 in the Unity engine, reading the user’s Ultimate Collection installation through its own C# code for the game’s DBPF packages and asset formats, which the project also aims to offer as modular libraries. README reports an early stage: a basic main menu with a neighborhood chooser, neighborhood previews and a basic neighborhood view, while the tree also holds lot, build-mode, Sim and SimAntics code. README credits FreeSO for much of its code and structure.

- Type: Case study
- Targets: Game
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-10-19
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/LazyDuchess/OpenTS2>
- Primary source: <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/README.md>
- Catalog page: <https://awesomerea.org/resources/opents2-sims2-engine-case/>
- Record JSON: <https://awesomerea.org/resources/opents2-sims2-engine-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/opents2-sims2-engine-case/index.md)

## Requirements & limits

- **Prerequisites:** Supply The Sims 2 Ultimate Collection. Copy config.example.json to config.json and set the game, user-data, expansion, and stuff-pack directories.
- **Scope:** OpenTS2 runs from the Unity editor and uses Unity 2020.3.32f1; Visual Studio 2019 is recommended. The README lists a basic menu and neighborhood views as current progress and names no supported play platforms.
- **Limits:** The repository has no releases or tags and does not supply the game installation. Its test packages include apparent excerpts of game data, including an effects package expected to contain 1,792 particle effects.
- **Testing evidence:** CI runs Unity Test Runner tests for DBPF packages and related fields; the README also describes integration test scenes.
- **License:** LICENSE.md uses MPL-2.0. Bundled third-party components retain their own terms; The Sims 2 and its game data belong to Electronic Arts.

## Primary sources

1. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/README.md>
2. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/LICENSE.md>
3. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/config.example.json>
4. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/ProjectSettings/ProjectVersion.txt>
5. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/.github/workflows/ci.yml>
6. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/TestAssets/README.md>
7. <https://github.com/LazyDuchess/OpenTS2/tree/bdabb07f4689ed91803a3d86dcbc8870b8832878/TestAssets>
8. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/Assets/Tests/OpenTS2/Files/Formats/DBPF/EffectsCodecTest.cs>
9. <https://github.com/LazyDuchess/OpenTS2/blob/bdabb07f4689ed91803a3d86dcbc8870b8832878/Assets/Tests/OpenTS2/Files/Formats/DBPF/Scenegraph/Codecs/ScenegraphAnimationCodecTest.cs>
10. <https://github.com/LazyDuchess/OpenTS2/tree/bdabb07f4689ed91803a3d86dcbc8870b8832878/Assets/Scripts/OpenTS2/SimAntics>
11. <https://github.com/LazyDuchess/OpenTS2/tree/bdabb07f4689ed91803a3d86dcbc8870b8832878/Assets/Scenes/Tests>
12. <https://github.com/LazyDuchess/OpenTS2/tree/bdabb07f4689ed91803a3d86dcbc8870b8832878/Notes>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.