A cross-platform, open-source, pure C game engine for mobile game
Game engine to build text adventures.
Orx: Portable Game Engine
0 A.D. is a free, open-source, cross-platform real-time strategy game.
Cross-platform 2D and 3D game engine
C/C++ , PHP, PYTHON, 3D ENGINES, CHROME NATIVE CLIENT
Cross platform administration tool for Source Engine dedicated servers