Modifications and Add-Ons Source Modifications
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Boom - DOS port with editing features and a number of bug fixes. Compiled and source downloads and a feature list available.
Client/Server Doom - Port for deathmatch play on the Internet. Offers downloads for Windows, FreeBSD and Linux, and a discussion forum. No longer maintained.
DelphiDoom - Translation of the GNU/Linux C source code of the classic 3D shooter game Doom to the Delphi programming language. Includes screen shots, videos, documentation and a message board.
DOOM 7650 - Port of Doom to a Nokia cellphone
Doom Legacy Wiki - Community resource, with news, documentation and editing tutorials.
Doom: System Administration Tool - Perform Unix administrator tasks with a Doom interface.
Doom3D - Windows port with Direct3D and splitscreen capabilities. Also supports full 3D stereoscopic effect.
Doomsday HQ - Home of the Doomsday Engine, jDoom, jHeretic and jHexen.
Eternity Engine - A Doom engine port based on Smack My Marine Up (SMMU). Includes scripting, portals, polyobjects, and Heretic support, and will power the upcoming Millennium and Mordeth TC modifications. Software rendering. (GPL) [Windows]
Freedoom - Volunteer project to create a free version of Doom data files (WADs). These can be used with any Doom engine. (3-clause BSD)
Fusion - DOS port based on MBF, with various extra features particularly for Dehacked work. Binaries, source code and editing demonstrations available.
Legacy - Engine with new features for enhanced deathmatch games, available for most major platforms. Contains discussion forums, development news, documentation, and links to derived engines.
NTDoom - Port to Windows NT, no longer developed. Binary and source downloads.
PDoom - DOS port, no longer updated. Source and binaries available.
PrBoom - A port for Windows and Linux that closely emulates the original game.
psDooM - A process monitor and manager for *nix systems, using Doom as an interface.
Risen3D - A Doom engine port based on Doomsday Engine. OpenGL rendering. (GPLv2) [Windows]
Vavoom - Source port that supports Doom, Heretic, Hexen and Strife. Screenshots, information, download, forums and editing information.
What is MBF, anyway? - Brief information about the Marine's Best Friend Doom engine, for DOS.
WinDoom - Windows port with higher resolutions and a console. Program download, source code, documentation and a front end available. Not updated.
ZDoom - Enhanced port for Windows. With compiled and source downloads, development news, tutorials for the new features and a discussion forum.
ZDoomGL - OpenGL port for Windows. Binary and source code downloads, and a discussion forum. Help build the largest human-edited directory on the web.