The new wad selection mechanism
By [WDJ]  March 23, 2010
Revised   May 9, 2010
Revised   Oct 30, 2010
Revised   Fed 22, 2011
Revised   Jan 12, 2014

The following command line switch will force the execution mode:
Syntax:  -game <mode>
Where <mode> is one of the following:
"freedoom"	=> GDESC_freedoom
"freedm"	=> GDESC_freedm
"doom2"		=> GDESC_doom2
"freedu"	=> GDESC_freedoom_ultimate
"doomu"		=> GDESC_ultimate
"doom1"		=> GDESC_doom_shareware
"plutonia"	=> GDESC_plutonia
"tnt"		=> GDESC_tnt
"blasphem"	=> GDESC_blasphemer
"heretic"	=> GDESC_heretic
"heretic1"	=> GDESC_heretic_shareware
"hexen"		=> GDESC_hexen
"hexen1"	=> GDESC_hexen_demo
"strife"	=> GDESC_strife
"strife0"	=> GDESC_strife_shareware
"chex1"		=> GDESC_chex1
"ultimode"	=> GDESC_ultimate_mode
"doommode"	=> GDESC_doom_mode
"heremode"	=> GDESC_heretic_mode
"hexemode"	=> GDESC_hexen_mode


The following is the table of recognized games and modes.
The gname is used to tag save games.
The idstr is used to make save game directories, and the selection switch.
The title appears at game start, to identify the wad.
The wad will be checked for having the required lumps.
The execution mode controls Legacy features and game play restrictions.
  doom_shareware = Doom shareware version
  doom_registered = Doom registered version
  ultdoom_retail = Ultimate Doom
  doom2_commercial = Doom2 with Boom extensions
  heretic = Heretic inventory etc.
  hexen = Hexen		(not implemented yet, May 9, 2010)
  strife = Strife	(not implemented yet, May 9, 2010)
  chexquest1 = Chex Quest extensions.

There are upto 3 possible filenames, all will be checked for -game.
The first filename is preferred and is usually unique.

Boom extensions and Legacy extensions will be active in all modes except
where a specific mode has incompatibilities.

GDESC_freedoom: FreeDoom project, DoomII replacement
   gname, title = "FreeDoom"
   idstr = "freedoom"
   file = "freedoom2.wad", "freedoom.wad", "doom2.wad"
   lumps = require "FREEDOOM"  "MAP01"
   gamemode = doom2_commercial
   
GDESC_freedm: FreeDM project, DoomII deathmatch
   gname, title = "FreeDM"
   idstr = "freedm"
   file = "freedm.wad", "doom.wad"
   lumps = require "FREEDOOM" "MAP01"
   gamemode = doom2_commercial

GDESC_doom2: DoomII
   gname ="Doom2"
   title = "DOOM 2: Hell on Earth"
   idstr = "doom2"
   file = "doom2.wad"
   lumps = require "MAP01" "TITLE"
   gamemode = doom2_commercial

GDESC_freedoom_ultimate: FreeDoom project, Ultimate Doom replacement
   gname ="Ultimate FreeDoom"
   idstr = "freedu"
   file = "freedoom1.wad", "freedu.wad", "doomu.wad"
   lumps = require "FREEDOOM" "E4M1" "E1M1" "E2M2"
   gamemode = ultdoom_retail

GDESC_ultimate: Doom1 1995, Doom1 1995 on floppy
   gname = "Ultimate Doom"
   title = "The Ultimate DOOM"
   idstr = "doomu"
   file = "doomu.wad", "doom_se.wad", "doom.wad"
   lumps = require "E4M1" "E1M1" "E2M2" but cannot have "TITLE"
   gamemode = ultdoom_retail

GDESC_doom: DoomI 1994
   gname ="Doom"
   title = "DOOM Registered"
   idstr = "doom"
   file = "doom.wad"
   lumps = require "E3M9" "E1M1" "E2M2" but cannot have "TITLE"
   gamemode = doom_registered
   
GDESC_doom_shareware: DoomI shareware
   gname ="Doom shareware"
   title = "DOOM Shareware"
   idstr = "doom1"
   file = "doom1.wad", "doom.wad"
   lumps = require "E1M1" but cannot have "TITLE"
   gamemode = doom_shareware

GDESC_plutonia: FinalDoom : Plutonia, DoomII engine
   gname ="Plutonia"
   title = "DOOM 2: Plutonia Experiment"
   idstr = "plutonia"
   file = "plutonia.wad"
   lumps = require "CAMO1" "MAP01" but cannot have "TITLE"
   gamemode = doom2_commercial

GDESC_tnt: FinalDoom : Tnt Evilution, DoomII engine
   gname ="Tnt Evilution"
   title = "DOOM 2: TNT - Evilution"
   idstr = "tnt"
   file = "tnt.wad"
   lumps = require "REDTNT" "MAP01" but cannot have "TITLE"
   gamemode = doom2_commercial

GDESC_blasphemer: FreeDoom project, DoomII replacement
   gname, title ="Blasphemer"
   idstr = "blasphem"
   file = "BLASPHEM.WAD", "blasphem.wad", "heretic.wad"
   lumps = require "BLASPHEM" "E1M1" "TITLE"
   gamemode = heretic

GDESC_heretic: Heretic
   gname, title = "Heretic"
   idstr = "heretic"
   file = "heretic.wad"
   lumps = require "E1M1" "E2M2" "TITLE"
   gamemode = heretic

GDESC_heretic_shareware: Heretic shareware
   gname, title ="Heretic shareware"
   idstr = "heretic1"
   file = "heretic1.wad", "heretic.wad"
   lumps = require "E1M1" "TITLE"  but cannot have "E2M2"
   gamemode = heretic

GDESC_hexen: Hexen
   gname, title ="Hexen"
   idstr = "hexen"
   file = "hexen.wad"
   lumps = require "MAP40" "MAP01" but cannot have "TITLE"
   gamemode = hexen

GDESC_hexen_demo: Hexen
   gname, title ="Hexen Demo"
   idstr = "hexen1"
   file = "hexen1.wad", "hexen.wad"
   lumps = require "MAP01" "TITLE"
   gamemode = hexen

GDESC_strife: Strife
   gname, title ="Strife"
   idstr = "strife"
   file = "strife.wad"
   lumps = require "ENDSTRF" "MAP20" "MAP01"
   gamemode = strife

GDESC_strife_shareware: Strife shareware
   gname, title ="Strife shareware"
   idstr = "strife0"
   file = "strife0.wad", "strife.wad"
   lumps = require "ENDSTRF" but cannot have "MAP01"
   gamemode = strife

GDESC_chex1: Chex Quest
   gname, title ="Chex Quest"
   idstr = "chex1"
   file = "chex1.wad", "chex.wad"
   lumps = require "W94_1" "POSSH0M0" "E1M1"  but cannot have "TITLE"
   gamemode = chexquest1

GDESC_ultimate_mode: Ultimate Doom replacement
   gname, title ="Ultimate mode"
   idstr = "ultimode"
   file = "doomu.wad", "doom.wad"
   lumps = require "E1M1"
   gamemode = ultdoom_retail

GDESC_doom_mode: DoomI replacement
   gname, title ="Doom mode"
   idstr = "doommode"
   file = "doom1.wad", "doom.wad"
   lumps = require "E1M1"
   gamemode = doom_registered

GDESC_heretic_mode: Heretic replacement
   gname, title = "Heretic mode"
   idstr = "heremode"
   file = "heretic.wad"
   lumps = require "E1M1"
   gamemode = heretic

GDESC_hexen_mode: Hexen replacement
   gname, title = "Hexen mode"
   idstr = "hexemode"
   file = "hexen.wad"
   lumps = require "MAP01"
   gamemode = hexen

GDESC_other: Other iwads, DoomII, Boom extensions, and Legacy extensions
   gname = name of iwad
   title = "Public DOOM"
   file = file from -iwad
   lumps = require "MAP01"
   gamemode = doom2_commercial
