Game engine to build text adventures.
Cross-platform 2D game engine (+ full OpenGL, +full OpenGL ES )
A tool to easily transform Unreal Engine games into VR experiences
Game engine supporting many 3D/2D formats and graphic effects
2D game development library for Ruby and C++
Vivid3D is an open-source 3D engine with powerful 2D UI.
Urho3D Game engine
A cross-platform, open-source, pure C game engine for mobile game
Engo is an open-source 2D game engine written in Go
Open source reimplementation of GTA San Andreas game engine in Unity
Open source reimplementation of GTA San Andreas game engine in Unity
a UCI chess engine
2D Game Engine
Cross-platform 2D and 3D game engine
A cross-platform 2D game engine
Free and Open Game Programming Language for Windows and GNU/Linux
Real-time RPG for PC/tablet/phone; multiple quests and random dungeons
Blueshift is a cross-platform 3D game engine implemented in C++
Portable game engine with main focus on point-and-click adventures
A project to create a blazingly fast Swift game engine
scriptable game engine with built-in support for 2D graphics and sound
online 4X browser game engine
The Atomic Game Engine is a multi-platform 2D and 3D engine
Open-source, cross-platform, C++ game engine for creating 2D/3D games