# Chocolate Doom installation

These are instructions for how to install and set up Chocolate Doom
for play.

# Obtaining an IWAD file

To play, you need an IWAD file.  This file contains the game data
(graphics, sounds, etc). The full versions of the games are
proprietary and need to be bought.  The IWAD file has one of the
following names:

|  IWAD                      | Game                            |
| -------------------------- | ------------------------------- |
|  doom1.wad                 | Shareware Doom                  |
|  doom.wad                  | Registered / Ultimate Doom      |
|  doom2.wad                 | Doom 2                          |
|  tnt.wad                   | Final Doom: TNT: Evilution      |
|  plutonia.wad              | Final Doom: Plutonia Experiment |
|  chex.wad                  | Chex Quest                      |
|  freedoom1.wad             | Freedoom: Phase 1               |
|  freedoom2.wad             | Freedoom: Phase 2               |
|  freedm.wad                | FreeDM                          |

If you don’t have a copy of a commercial version, you can download
the shareware version of Doom (extract the file named doom1.wad):

 * https://www.doomworld.com/idgames/idstuff/doom/win95/doom95
   (idstuff/doom/win95/doom95.zip in your nearest /idgames mirror)

If you have a commercial version on a CD-ROM, obtaining the IWAD
file is usually straightforward. Simply locate the IWAD file on the
disc and copy it off.

The Doom games are available to purchase for download on Steam
(https://store.steampowered.com/), all releases containing the classic
games including Doom 3: BFG Edition are supported.
For Steam on Linux, you need to enable “Steam Play” for all titles in
order to install the games.  You may do this from the Steam menu,
Setup, and the Steam Play tab.
Chocolate Doom will autodetect IWADs installed by Steam and you do not
need to do anything.

The Doom and Strife: Veteran Edition games are available for purchase
on GOG.com (https://www.gog.com/).
The games are only available for Windows, but you may find the IWAD
files on a Windows or Wine system, typically within the “C:\GOG Games”
or “C:\Program Files\GOG Galaxy” directories.

Older floppy disk versions are harder to deal with. The easiest way
to install from floppies is to run the original installer program
inside an emulator such as DOSbox (https://www.dosbox.com/).
As an alternative to using an emulator, it is possible to extract the
files manually. On the install disk(s), you will find several files
with numbered extensions (eg. “doom_se.1”).

From the command line it is possible to combine these files into a
single large file, using a command similar to the following:

   cat doom_se.1 doom_se.2 doom_se.3 doom_se.4 doom_se.5 > doom_se.lzh

The resulting file is an LHA archive file, and it can be extracted
using an LHA archive tool (there is one available for almost every
operating system).

# Running the game

Chocolate Doom needs to know where to find your IWAD file. To do this,
do one of the following:

 * Run Chocolate Doom from the Unix console with the `-iwad` command
   line parameter to specify the IWAD file to use, eg.

       chocolate-doom -iwad /root/doom2.wad

 * Put the file into one of the following directories:

     $HOME/.local/share/games/doom
     /usr/share/doom
     /usr/share/games/doom
     /usr/local/share/doom
     /usr/local/share/games/doom

 * Set the environment variable DOOMWADDIR to specify the path to a
   directory containing your IWAD files.

 * If you have multiple IWADs in different directories, set the
   environment variable DOOMWADPATH to be a colon-separated list of
   directories to search (similar to the Unix PATH environment
   variable).

# Playing with Freedoom

Freedoom is an open content project to create a Doom engine-based game
that is entirely free software. The website can be found here:

  https://freedoom.github.io/

Check out the [Chocolate Doom wiki’s page on
Freedoom](https://www.chocolate-doom.org/wiki/index.php/Freedoom)
for more information.

# Playing with Chex Quest

Chex Quest is a game based on Doom with some minor modifications that
was distributed with boxes of Chex cereal in 1997.  It is possible to
play Chex Quest using Chocolate Doom.  To do this, the following files
are needed:

 * The IWAD file “chex.wad”, from the Chex Quest CD.

 * The dehacked patch “chex.deh”, which can be found here:
   https://www.doomworld.com/idgames/themes/chex/chexdeh
   (themes/chex/chexdeh.zip in your nearest /idgames mirror)

Copy these files into a directory together and use the `-iwad` command
line parameter to specify the Chex Quest IWAD file:

   chocolate-doom -iwad chex.wad

# Installing upgrades

Chocolate Doom requires a version 1.9 IWAD file.  Generally, if you
install a recent version of Doom you should have a version 1.9 IWAD.
However, if you are installing from a very old CD version or from
floppy disks, you might find you have an older version.

The most obvious symptom of an out of date IWAD file is that the game
will exit at the title screen before the demo starts, with the message
“Demo is from a different game version!”.  If this happens, your IWAD
file is out of date and you need to upgrade.

Upgrade patches are available that will update your game to the latest
version, the following sites have the patches:

  * http://www.doom2.net/doom2/utils.html
  * http://www.gamers.org/pub/idgames/idstuff/doom
  * http://www.gamers.org/pub/idgames/idstuff/doom2

Please see the
[Doom Wiki’s page on game patches](https://doomwiki.org/wiki/Game_patch)
for more information.

As the patches are binary patches that run as DOS executables, you
will need to use a DOS emulator (such as DOSBox) to run them.

# Music support

Chocolate Doom includes OPL emulation code that accurately reproduces
the way that the in-game music sounded under DOS when using an
Adlib/Soundblaster card. This is, however, not to everyone’s taste.

Chocolate Doom includes a number of different options for better
quality MIDI playback; see the file README.Music for more details of
how to set these up.

