ZDoom

ZDoom is a source port, originally based on ATB Doom and NTDOOM. It has since added full support for all commonly-used Boom additions, Heretic, Hexen, Strife and Chex Quest. It has added many additional features, including slopes, uncapped framerate, and z-clipping. The source code is maintained by Randy Heit and Graf Zahl. The large number of modding features supported by ZDoom made it the port of choice for several independent game projects, notably Foreverhood, Action Doom 2: Urban Brawl, Chex Quest 3 and Harmony. ZDoom has also served as a popular codebase to build on, with numerous other source ports derived from it or using portions of its code.

Many in the Doom community use development versions of the port before they are officially released as stable builds. In addition, due to the complexity of ZDoom's enhanced engine, new versions rarely maintain : many a PWAD runs only with the version current at that time.

Features

 * Support for all of Hexen's editing features (including ACS, hubs, and new map formats).
 * Support for most of Boom's editing features
 * Support for several of MBF's editing features, including friendly monsters and loading DeHackEd patches directly.
 * Support for UDMF
 * Support for all Doom engine games: the various versions of Doom, Heretic, Hexen, Strife, Chex Quest and even Freedoom is identified as its own IWAD rather than being taken for Doom 2: Hell on Earth.
 * Removal of most vanilla Doom limits (including the visplane overflow).
 * High screen resolutions (with optimizations for modern processors).
 * Translucency (regular and additive).
 * A console.
 * Additional control options including crosshairs, free look, jumping and crouching configurable via Quake-style key bindings.
 * OPL emulation and GENMIDI support.
 * More music and sound formats: MOD, XM, IT, S3M, MIDI, OGG Vorbis, SPC, FLAC and MP3, as well as MUS.
 * Support for PNG, JPG, TGA and DDS format images.
 * Greatly enhanced texture definition lump allowing scaled textures (for high-resolution), as well as compositing multipatch texture using independent rotation, mirroring, alpha transparency level and either translations or color blending for each patch.
 * DECORATE script: a simple yet powerful actor definition language.
 * Limited UDP Internet or LAN networking inherited from Linux Doom.
 * Walking over/under monsters and other things.
 * Runs under Windows 9x, NT, XP, Linux and Mac OS X.
 * Support for Doom Connector and Player Connector network games.
 * 3D middle textures, slopes and colored lighting.
 * Decals on walls for scorch marks and blood splatter.
 * Support for custom player skins.
 * A chasecam.
 * Many camera effects, including Duke Nukem-style security camera or Unreal-style skyboxes. Cameras can even replace the player view, allowing for scripted cutscenes or alternative gameplay mimicking a sidescroller.
 * Support for using features of every supported game in all of them -- for example, a Doom map can feature Strife conversations, Hexen scripting and actors that use Heretic codepointers.
 * Support for loading resources directly from ZIP or 7z files, making the use of the traditional WAD file format optional except for map lumps.
 * ENDOOM and animated start up screen support

Ports based on recent versions of ZDoom
These ports support most or all of the features listed above.
 * GZDoom
 * Skulltag

Ports based on older versions of ZDoom
These ports are not necessarily compatible with recent ZDoom mods.
 * bZdoom
 * csDoom
 * Odamex
 * ZDaemon
 * ZDaemonGL
 * ZDoomGL