Orbinaut Framework 2 is the successor to the original Orbinaut Framework, a classic Sonic framework created for GameMaker. It prioritises ease-of-use and includes a templated foundation to help new users get started (basic programming and GameMaker IDE knowledge is required).

Built entirely from scratch, the framework is designed with extreme accuracy in mind, faithfully replicating the original games' internal systems and game loop.

However, while it strives to match the look and feel of the four classic Sonic titles, the framework comes with some intentional limitations to maintain authenticity. Experienced GameMaker developers can expand upon this base to create non-Sonic gameplay thanks to Orbinaut's modular design.

If you're comfortable enough with OF2 and want a bit more, a director's cut version of the framework, called the Sol Framework, is available here. Please note that no support or assistance will be provided for it.

Orbinaut Framework 2 is specifically designed to work with the LTS'25 version of GameMaker and its preceding regular release. Compatibility with other versions is neither supported nor guaranteed.

OF2 includes detailed documentation, accessible in the Wiki section. While you might be tempted to skip it, be sure to review the installation guide to ensure everything is set up correctly.

• All gameplay objects in the framework provided by default are accurate to their Sonic 2 presentation, both code and animation-wise.
• Character physics, character-to-object, and object-to-terrain collisions are fully and faithfully recreated, delivering behaviour identical to the original games, making OF2 one of the most accurate classic Sonic frameworks ever made.
• Four playable characters are available: Sonic, Tails, Knuckles, and Amy (Origins).
• Support for multiple player objects, which can be set up to be controlled by either a CPU or a real person.
• Up to 8 player splitscreen support.¹
• The ability to customise gameplay by toggling various differences between the four classic titles, ensuring you get the experience you want to have in your game.
• The framework offers various graphical effects you can see in the classic games, including its own background parallax, palette rotation, palette-based fade in/out and screen distortions.
• Overall, most methods are accurate or similar to the ones used in the original Sonic engine.

The framework is complete with all features working as intended and ready for use. We will update the repository if a major GameMaker update is released that introduces significant changes, such as alterations to the project format.

If you have any questions about the framework, feel free to use the Discussions tab. All major news will be posted there and on Twitter. Please, do not use it for bug reports.

• Founders: Triangly, Michael Gallinago
• Programmers: Triangly, Michael Gallinago, techncolour
• Framework Branding & Sprite Edits: Natufox
• Framework Trailer: Lapper, Triangly
• Tech Stadium Zone: Enrico Cartmanuel
• Level Design: FieryN8
• "Giganorbi" Boss Programming: techncolour
• Discord Rich Presence Plugin: nkrapivin
• Special Thanks: Lapper, Mercury, NicoCW, Valeev, Noah N. Copeland, The Sonic 1, 2 and 3 Dissasembly Community, and our Twitter followers!

• For fangames: non-profitable, as always.
• For original IPs: MIT License.

Please credit us as Team Orbinaut.
We'd also like to ask that you not distribute a modified versions of the framework, thank you!

¹ Default splitscreen support is basic, providing separate screens for CPUs that can be taken under control like in Sonic 2 or Sonic 3(K). There is no "complete splitscreen experience", as you may call it that.