CRX (game engine)
The CRX game engine is an opensourced, cross platform program that was derived from id Software's GPL code releases by COR Entertainment. The engine is primarily used for the game CodeRED: Alien Arena. The engine makes use of Quake II data formats such as .md2 and the BSP map format. The engine runs on Windows, Linux, and FreeBSD. The engine has also been ported to MacOS by third-parties.
Technical specifications
CRX makes use of GLSL for per-pixel lighting, parallax mapping, normal mapping, and specular highlights for the majority of its rendered surfaces. The engine supports the use of 32-bit TARGA with alphamasking, as well as JPEG image formats. Stencil buffer shadows are used as simple planar shadows, as well as stencil volumes. Fog, weather effects, textured particles, lens flares, and light volumes are among some of the other renderer features. The audio is handled by OpenAL by Creative Labs, and supports effects such as Doppler.
The netcode is based on the original Quake 2 source, with some changes such as antilag (backwards reconciliation) and packet prioritorization, and [Http] downloading of media content. A built-in server browser assists users in finding online games.
Critical Acclaim
While CRX isn't as widely used as some other Quake-based gaming engines, it has received it's share of press, mostly through tech reviews of CodeRED: Alien Arena and gaming engine tech articles.