@chapter{ Games }

@section{ Loading IWADs }

Doomsday requires @link{IWAD files}{http://wiki.dengine.net/w/WAD} to run
games. You can use the following ways to let the engine know where your IWADs
can be found:

@list{

    @item The first time you launch Doomsday and it doesn't find any IWADs, it
    will show a tab titled @ui{Data Files?} containing a single button.
    Clicking the button opens a file dialog where you can pick a folder where
    your IWAD files are located.

    @ifdef{UNIX}{@item The directory @file{/usr/share/games/doom} is always
    checked for any recognized IWAD files.}

    @ifndef{UNIX}{@item If you have Steam installed, Doomsday will
    automatically detect if you have purchased a compatible game and will
    access the IWAD files in the Steam games directories.}

    @ifdef{WIN32}{@item Compatible games purchased from
    @link{GOG.com}{https://gog.com} are autodetected.}

    @item Using the @opt{-iwad} command-line option. You can either provide the
    path to the IWAD to use, or the path of the directory under which IWADs are
    located. Doomsday will look through the specified location and use all the
    recognized IWADs automatically. In other words, you can have the IWADs for
    all games stored in a single directory; Doomsday will use the appropriate
    one for each launched game.

    @opt{-iwad} will also accept multiple paths as parameters:

    @samp{@opt{-iwad path1 path2}}

    @ifndef{WIN32}{@item The configuration file @file{~/.doomsday/paths} is
    checked for @var{iwaddir} (see @ref{paths_file}{Files}).}

    @item Environment variables DOOMWADDIR and DOOMWADPATH (see
    @ref{environ}{Environment}).

    @item The configuration variable @var{Config.resource.packageFolder}. This
    is typically set automatically via the user interface, for instance when you
    first start Doomsday. Its value can also be manipulated in the Doomsday
    Script command prompt. (The variable @var{Config.resource.recursedFolders}
    determines if subdirectories should be searched.)

}

Doomsday tries to recognize IWAD files based on their contents. The
@link{identification
criteria can be viewed in GitHub}{https://github.com/skyjake/Doomsday-Engine/blob/master/doomsday/apps/libdoomsday/net.dengine.base.pack/databundles.dei}.

@a{gamemode} @section{ Supported games }

One game plugin, such as the @plugin{Doom Plugin}, is able to run many
different variants of the game. Each variant emulates a specific version of the
original game and typically has its own IWAD file.

Below is a list of all the games supported by the game plugins distributed
with Doomsday.

@table{19 25 56}{
	@header{Plugin} @tab @header{Game ID} @tab @header{Description} @row{single}

@plugin{Doom}
    @tab doom1-share @tab Shareware Doom v1.9 @row
	@tab doom1 @tab Registered Doom v1.9 @row
	@tab doom1-ultimate @tab Ultimate Doom* @row
	@tab doom2 @tab Doom 2 @row
	@tab doom2-plut @tab Final Doom: Plutonia Experiment @row
	@tab doom2-tnt @tab Final Doom: TNT Evilution @row
	@tab chex @tab Chex Quest @row
	@tab hacx @tab HacX @row
    @tab doom1-freedoom @tab Freedoom Phase 1 @row
    @tab doom2-freedoom @tab Freedoom Phase 2 @row
    @tab doom1-bfg @tab Ultimate Doom (Doom 3 BFG Edition) @row
    @tab doom2-bfg @tab Doom 2 (Doom 3 BFG Edition)@row
    @tab doom2-nerve @tab No Rest for the Living @row

@plugin{Heretic}
    @tab heretic-share @tab Shareware Heretic @row
	@tab heretic @tab Registered Heretic @row
	@tab heretic-ext @tab Heretic: Shadow of the Serpent Riders** @row

@plugin{Hexen}
    @tab hexen @tab Hexen v1.1 @row
    @tab hexen-v10 @tab Hexen v1.0 @row
	@tab hexen-dk @tab Hexen: Death Kings of Dark Citadel @row
	@tab hexen-demo @tab The 4-level Hexen Demo
}

@caption{* = has a 4th episode @br ** = has episodes 4 and 5}

