Doomsday

From its official Web site, the Doomsday Engine is an enhanced and extended version of DOOM, Heretic, and Hexen. It was originally based on the Hexen source code but parts of it have later been completely rewritten. Doomsday is only an engine; you will need a Game DLL if you want to play anything. Three such DLLs are being developed alongside the engine: jDoom, jHeretic and jHexen.

Doomsday features:

* Runs in Windows, Mac OS X, and Linux. * Supports OpenGL and Direct3D for crisp, hardware accelerated graphics. * 3D models (Quake's MD2 format) can be used instead of sprites. * Object and camera movement smoothing. * Simple shadows for objects. * Dynamic light effects and lens flares. * Particle effects. * 3D sound effects with DirectSound3D and EAX 2.0 or A3D 3.0. Also supports EAX's and A3D's environmental sound effects. * High-resolution textures (PNG, TGA, PCX) and detail textures. * 16-player client/server networking via TCP/IP, IPX, modem and serial link. * Easy to use Control Panel for configuration, accessed quickly with Shift-Esc. * Console for modifying settings and giving commands. * Utilizes FMOD to play a wide variety of music files, for example MP3, MOD and IT. * Uses plain text definition files for some game data such as thing types and states, sound and music information, level configuration (sky, fog, gravity) and text strings.