Proto:Doom II: Hell on Earth (PC)

This page details one or more prototype versions of Doom II: Hell on Earth (PC).

This article is a work in progress. ...Well, all the articles here are, in a way. But this one moreso, and the article may contain incomplete information and editor's notes.

To do: Prototype of the Xbox 360 port from May 5th, 2010. 2 days before the final build was complied.

While no prototypes of Doom II's WAD file (used for most game data) are known to exist, the Doom betas released by id throughout 1994, along with the earlier bootleg version, all have some support for the game. These give some insight into Doom II's development, and while it's not a complete picture, it's still pretty interesting.

All Versions

Loading Doom II

Simply having DOOM2.WAD in the same directory as a beta executable is enough to load it, since like the final version they give it priority over the registered or shareware version of Doom. However, certain required resources are not present in the final WAD. These resources are in the registered DOOM.WAD, however, so the following command line can be used to load the game without modifying anything:

doom -file doom.wad doom2.wad

This will load the resources from DOOM.WAD, then reload those from DOOM2.WAD, replacing any shared between games and fixing sprite and flat graphic loading.

General Differences

• The episode selection and "Read This!" menus are still present.
  • Changing the episode only affects the sky, music, and map names used. The game is already set up to load levels from MAPxx lumps like the final version.
• Doom filenames are used for music and the intermission level names.
• The level names on the automap are still from Doom. MAP10 = E2M1.

Monster Behavior

Arachnotron

• Uses the Spider Mastermind sounds.
• Does not fire plasma, instead it has a chaingun! This chaingun fires with the same sound as the player's, unlike the Heavy Weapon Dude and Spider Mastermind, who use the Shotgun's sounds.
• Crashes the game when killed, due to using a sprite frame not present in the final version.

Bootleg v1.3/1.4

A version of Doom leaked on April 8, 1994. It shouldn't be confused with the official v1.4 beta. The internal version is actually 1.3, but the startup text in the most widely available copy has been hacked to read 1.4 instead of printing the version number integers. This is the first version of the engine with support for Doom II, however at this time it doesn't expect DOOM2.WAD, but instead DOOMR.WAD, so you will need to rename your WAD file and adjust the command line appropriately.

General Differences

• Progression between levels still uses Doom behavior:
  • Completing MAP08 will show the episode 1 end text.
  • MAP09's exit leads to MAP04, since E1M9 was a secret level.
  • MAP10 and beyond will crash the game on exit.
• The intermission screens use Doom's backdrops.

Things

To do: Document in depth.

Most things aren't present in this version, meaning very few maps can be played. MAP01 and MAP13 work.

Monster Behavior

To do: Screenshots or videos. Probably videos.

Arch-Vile, Heavy Weapon Dude, Revenant

• Placeholders:
  • Use Shotgun Guy sprites for their walking animations, but Heavy Weapon Dude sprites for their attacking and dying animations.
  • Use the Heavy Weapon Dude's attack.
  • Use former human sounds.

Hell Knight

• Uses the Baron of Hell sprites and sounds, but already has half its health.

Mancubus

• Uses the former human sight, pain, and death sounds. Has no action sound when firing.
• Fireballs use the same sprites as the Baron of Hell projectiles.
• The final death frame is not used.

Sybex v1.25

This is a shareware version that came with The Official Doom Survivor's Strategies & Secrets guide published by Sybex. Its files are dated April 21, 1994. Strangely, despite the lower version number, this appears to be an intermediate version between v1.3 and v1.4. The engine now expects DOOM2.WAD and the startup text reads "DOOM System Startup" instead of "DOOM Operating System".

Monster Behavior

Heavy Weapon Dude

• Now identical to final.

Mancubus

• Now uses the Baron of Hell's sight sound before firing.

Beta v1.4

id's official v1.4, released on June 28, 1994. Unfortunately, it requires eight textures which are not present in either WAD and will refuse to run levels without them.

To do: Put a download for my WAD with the GDOORx# textures.

Line Actions

Sliding Door

To do: Video.

124 can be used to create a horizontally sliding door! Anyone familiar with Doom's renderer knows that a sector can only change vertically, the result of using a static BSP tree defined in the NODES lump for each map. To work around this limitation, a door created with this action isn't a sector at all: the line's front side middle texture animates through GDOORF1-4 when activated, while the back animates GDOORB1-4. When the animation is complete, the blocking flag is unset from the line. Activating the door a second time will play the animation back in reverse and reset the blocking flag. This action's reliance on these animated textures is why a separate WAD must be loaded to play this beta, and is likely why this line action has been restricted to Doom II.

These doors are far from perfect, since the blocking flag doesn't block hitscans or projectiles, meaning they pass through the doors like they're not even there. The animations are also very choppy and unconvincing, a result of only using four frames. The code for these doors is actually still present in the released source code, but the action to activate them has been commented out. The code for these doors was later altered for Strife's animated doors.

Monster Behavior

Pain Elemental

• Uses final sprites, but behavior is identical to a Cacodemon.

Beta v1.5

id's second shareware beta, released on July 8, 1994. As the code for sliding doors is still present, you'll still need GDOOR.WAD linked above to run levels.

General Differences

• The intermission screen now uses the TITLEPIC as the backdrop, but darkens it. The final version has its own INTERPIC graphic for intermissions.

Monster Behavior

Arch-Vile

• Uses former human sounds.
• Attack is identical to the final version, but it uses the teleport fog sprites as a placeholder for the fire, and plays BFG firing sounds. This is actually mentioned in an early interview, where the interviewer states that the AV attacks with plasma.

Pain Elemental

• Now has final behavior.

Revenant

• Jumps before firing a rocket!
• Always fires homing rockets.
• Rockets use the same sprites as the Cyberdemon and player's do, but with a smoke trail like the final rocket.

Beta v1.6

The last shareware beta, released on August 3, 1994, predating the release of Doom II by a little under two months.

General Differences

To do: Test all level progression, including secret exits and the secret levels. Might be something different to find here.

• The GDOORx# textures are no longer referenced.
• Level progression is now similar to the final version, but without the text screens.

Leaked v1.666 Build

A near-final build, dated August 25, was leaked on August 30 by the group Razor 1911. At this point, DOOM2.WAD is identical to the proper v1.666 release, but the executable still has a few differences.

General Differences

To do: Do any of these differences also exist in the previous builds?

• Trying to load any PWADs alongside DOOM2.WAD causes an error if the IWAD doesn't contain certain lumps - specifically: FATTI5, MAP20, KEENA0, VILEG1, and SKELG1, presumably to prevent people from playing Doom II PWADs using a renamed Doom IWAD. The registered version of Doom uses similar behavior to detect renamed shareware IWADs, but the release version of Doom II doesn't do this.
• In the final release, if MAP01 is missing from DOOM2.WAD, the game will enter a "rolling demo" mode that ignores all input from the player. This feature is missing from this build.
• In the final release, if MAP31 is missing from DOOM2.WAD, secret exits will have the same behavior as normal exits; this is due to the secret levels being removed from the German release of the game. In this build, a secret exit can attempt to take you to MAP31 even if it doesn't exist.
• In this build, loading and saving games doesn't use a hardcoded save game directory when running from the CD.

(Source: Original TCRF research)