Wear negative armor!

[cybermind]

Well, this is my answer to that thread

First off:

http://doomwiki.org/wiki/Armor_percentage_rollover said:

In versions of Doom 1.2 and earlier, armor percentage was not limited to 200.
[...]

There is no set limit to the amount of armor that a player can accumulate in these versions of Doom, so theoretically, a player could overflow the signed integer variable for the armor percentage, and consequently have a negative amount of armor. However, the limitations of the WAD format make it impossible to construct a level or series of levels containing the billions of armor bonuses necessary to cause such an overflow.

No way, it's possible! Here's the answer: https://www.dropbox.com/s/hgsc27i0bc91u5n/negarmor.zip?dl=0

To run this wad, obtain Doom v1.1/shareware Doom v1.0 and type in command prompt:
doom.exe -devparm -file negarmor.wad -wart 1 9

[Gez]

Picked up the NegaArmor¡

[RjY]

You seem to have placed the bonus in a shallow pit, making it unlikely to be picked up, unless the player deliberately walks slowly.

[cybermind]

RjY said:

You seem to have placed the bonus in a shallow pit, making it unlikely to be picked up, unless the player deliberately walks slowly.

The negaarmor is not easy to be obtatned!
Of course, you may also place additional 65534 armor bonuses (vanilla engine could handle that, but don't do anything except keeping exiting) in that pit to reduce levels required to obtain negative armor.

[dew]

So, I kinda dug into this matter...

Demos.

All the details are in the textfile/video description. Sadly, it leaves some questions open.

[baja blast rd.]

dew said:

https://www.youtube.com/watch?v=NIO-lQROZoM

Diowneow-neowneoewneow-neow-neowneow dit-dit-dit-dit-dit-dit-dit-di, diowneow-neowneoewneow-neow-neowneow dit-dit-dit-dit-dit-dit-dit-di, diowneow-neowneoewneow-neow-neowneow dit-dit-dit-dit-dit-dit-dit-di

[Doomkid]

oh my god dew 21 seconds into that I got fucking jumpscared by that loud classical music, holy shit

[HavoX]

What, this doesn't take me to the Minus World? What a letdown.

[cybermind]

Wow, dew, you made it! If you don’t mind my asking, have you used some automation tools to make those demos? It's unbelievable that you just kept pressing "use" button for 7 hours. I would have checked this nega-armor using debugger first, but I was too lazy to search for armor variable pointer in the memory.

Kinda strange that your vanilla executable couldn't run a map with 65535 armor bonuses. I have registered doom version 1.1 and it loads the map properly.

[dew]

Haha, of course I used automation. I wrote the first exit in a hex editor, then copypasted the segment enough times. At 18 tics per iteration, it's the shortest playthrough possible and any extra unnecessary tics would greatly inflate the demo.

I used a 1.2 exe made by downgrading 1.9 to 1.1, then upgrading that again. I'll have to check 1.1 then, because I doubt it could be Dosbox's fault. Could you try to play back rollovr2.lmp with negarmr3.wad then? The demo has the original short header, so it should run with 1.1 and it has enough iterations to roll over even on the 44k helmet map, including a blind playthrough of the start of e1m4 at the end. If you can run that, please wait for about 7 hours. :)

[cybermind]

Yeah, v1.2 crashes for me too. v1.1 runs ok, but it doesn't support multi-level demos, making the bug unrecordable.

[Quasar]

Can you please elaborate on what "Doesn't matter though, because the game cannot handle it. It's too busy loading up the helmets. I mean, that's my theory." means? What is the game actually doing?

[Linguica]

Well, for 43898+1 things on the level, the game needs approx. 429 KB to load the THINGS lump, then another ~6688 KB to generate all the mobj_t's needed. So if you have a 6 MB memory limit, I'm not sure how it would work at all.

[dew]

Yeah, I played with the item count and demo size, but it wouldn't even run until I trimmed the former to about 32k things and the latter A LOT, which of course defeats the purpose. The demo route won't fly.

[pavera]

Really cool demonstration. This makes me wonder though...when Doomguy's armor goes negative, what is his torso covered by? o.o

[Frisky]

Y'know, Negative Armor! That thing that REALLY makes the Nightmare difficulty a nightmare!

[Gez]

Pavera said:

Really cool demonstration. This makes me wonder though...when Doomguy's armor goes negative, what is his torso covered by? o.o

An armor, but made out of antimatter. So when an attack hits, it explodes violently.

[Linguica]

Gez said:

An armor, but made out of antimatter. So when an attack hits, it explodes violently.

Seems legit to me.

[pavera]

There's an interesting gameplay scenario in here somewhere. Could act as a deliberate power-down to introduce some intensity to certain fights. Drop the player into an area, and force him to grab the Anti-Matter Armor, then proceed to assail him with imps and cacodemons. Bullet hell!

[ClumsyDoomer]

I laughed.

Pavera said:

Really cool demonstration. This makes me wonder though...when Doomguy's armor goes negative, what is his torso covered by? o.o

Look, he carried over 2 billion helmets. When he got shot, he had lost the balance and the helmets had crushed his body.

[Quasar]

Gez said:

An armor, but made out of antimatter. So when an attack hits, it explodes violently.

I'd like to see a Kurashiki-style take on this, with the armor being all darkish purple and evil like dark matter/energy in Metroid Prime 2, and the Doomguy looking very distressed by having it on.