OpenGGF
Fan-Made Open-Source Sonic Engine
Fan-Made Open-Source Sonic Engine
Fan-Made Open-Source Sonic Engine
About
OpenGGF is an open-source, OpenGL-accelerated game engine written in Java that faithfully reimplements the classic 16-bit Sonic the Hedgehog games — physics, collision, rendering, and audio are all verified against community-maintained disassemblies for accuracy.
OpenGGF is a community-made fan project. It is not affiliated with, sponsored by, approved by, or endorsed by Sega. It runs from your own legally-obtained ROM images, and no copyrighted assets are included.
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Community-made fan project. Not affiliated with Sega. Requires a legally-obtained ROM; no ROMs or copyrighted assets are included. JDK 21+.
Releases
- v0.5.20260411 2026-04
- v0.5.prerelease (pre) 2026-03
- v0.4.20260304 (pre) 2026-03
- v0.3.20260206 (pre) 2026-02
- v0.2.20260117 (pre) 2026-01
- v0.1.20260110 (pre) 2026-01
News
All news →FAQ
Do I need a ROM?
Yes — OpenGGF requires a legally-obtained ROM image. None are distributed with the engine.
Which games are supported?
The mainline 16-bit Sonic titles: Sonic 1, Sonic 2, and Sonic 3 & Knuckles.
Is this affiliated with Sega?
No. OpenGGF is a community-made, open-source fan engine. It is not affiliated with, sponsored by, approved by, or endorsed by Sega.