
             What is a WAD File? What kinds of WAD file are there?

                            2nd Edition: 21/Feb/95

(Thanks to Tom Neff (tneff@panix.com) for muchos corrections to my initial
innacurate witterings :)

Note for Shareware Doom players: add-on levels cannot be used with Shareware
Doom. See below for more info.

Q: What is a WAD file? What do they contain?

The file that comes with the game, namely DOOM.WAD, or DOOM1.WAD, or
whatever (it's the big one) contains all the information that the game
needs to know about the layout of the various levels, the graphics used,
objects, creatures, sounds, music and so on.

This file, or a modified version of it, is called an IWAD file - it is
the main data file which Doom loads.

Now that Doom level editors exist (such as Deu, DOOMED, DoomCAD, etc),
people can design their own add-on levels. These are loaded 'alongside' the
IWAD file and searched first during gameplay. When this is done, the IWAD
file is NOT changed in any way.

Such a file is a PWAD file, i.e. any additional file loaded after the IWAD
file is loaded.

The bad news (if you have the shareware version only) is that ID requested
that people making editors design them so that they will not create levels
that can be used with the Shareware version of the game, in order to
encourage people to buy the full version and, therefore, help ID make even
more excellent games.

Also, it is widely accepted practice amongst PWAD designers that PWAD files
are constructed so that they contain textures, weapons, etc., which are NOT
in the Shareware IWAD file (such as a plasma rifle); in this way, a PWAD
designer can put a non-shareware texture in the very first room, say, which
will crash out Shareware Doom straight away.

So, if you currently only have the Shareware version, all the more reason
for you to rush out and buy the full game! :) Editors, PWAD's, sounds, etc,
etc... :)

It is _possible_ to make PWAD's that will work with the earlier Shareware
versions of Doom, but the latest versions of Shareware Doom will simply
refuse to load them.

Hope this helps.

Byeee! :)

Ian.

The Doom Help Service (DHS).
Co-ordinator of rec.games.computer.doom.help.

WWW addresses:   

  Home page:     http://www.cee.hw.ac.uk/~mapleson/
  DHS:           http://www.cee.hw.ac.uk/~mapleson/doom/doom.html
  Help Archive:  http://www.cee.hw.ac.uk/~mapleson/doom/doomhelp.zip
  Dissertation:  http://www.cee.hw.ac.uk/~mapleson/diss/diss.html
  SGI Stuff:     http://www.cee.hw.ac.uk/~mapleson/sgistuff/sgindex.html

Ian C. R. Mapleson BSc.,
Oceans Systems Research Group,
Room G86,
Department of Computer Science and Electrical Engineering,
Heriot Watt University,
Riccarton Campus,
EH14 4AS,
Edinburgh,
Scotland,
United Kingdom.

email to: mapleson@cee.hw.ac.uk

