⚡ C/C++ Open Source Engines
| Engine | Primary Language | License | Key Strengths for You |
| : | : | : | : |
| Godot | C++ (core) / GDScript, C , or C++ (for modules) | MIT | The most popular open source alternative. The core is clean C++17. You can write GDScript for rapid iteration or bypass it entirely by writing engine modules and GDExtensions in C++. It's lightweight, has a great editor, and no strings attached. |
| Open 3D Engine (O3DE) | C++ | Apache 2.0 | The heavy lifter. Forked from Amazon's Lumberyard (which was based on CryEngine), this is a AAA capable engine backed by the Linux Foundation. It's complex, but for a veteran low level dev, that means power. No fees, full source access. |
| Cocos Creator | C++ | MIT | A long standing, mature choice, especially strong for 2D but with solid 3D capabilities. It's known for being highly performant on mobile and web. Millions of developers use its core, cocos2d x . |
| Urho3D | C++ | MIT | The "lean and mean" option for 3D. It's lightweight, extremely well documented, and has a very clean codebase with minimal bloat. It was designed to be a complete engine you can understand and modify entirely. Comes with a built in editor and Lua scripting if you want it. |
On License Pragmatism : The MIT license (Godot, Urho3D, Cocos, ColumbaEngine) is the gold standard for your use case. It allows you to do anything with the code, including selling your game or your modified engine, without owing anyone a cent.