[63] Bug: Monster Alert Behavior

[Phoenix9000]

The monster alert behavior differs from what I'm used to seeing in Doom. I've tested this a few times with Doom.exe, and here's what I've found:

In Doom, if a monster is hit by another monster it will do the following after killing the attacking monster, depending on the circumstances:

1) If the player has not audibly alerted the monster (it's only seen the player) and is not visible at the time one monster kills the other, the victor monster will return to an "idle" state and will not seek the player until alerted again.

2) If the player has audibly alerted the monster, and is not visible at the time one monster kills the other, the victor monster will make it's "alert" noise and seek the player.

3) If the player has audibly alerted the monster, and is visible at the time one monster kills the other, the victor monster will seek the player but not make it's "alert" noise.

In Zdoom the monsters are staying alert regardless of how the player initially wakes them up.

[Graf Zahl]

Yes, that's true. That was a change made by Boom in 1998. Don't expect it to go away.

The explanation for this is simple: Boom added an information to each monster that remembers its last attacker before the current one so that it doesn't go back to sleep after being distracted shortly by some other monster. It was a fully intentional change to the way the game works.

For reference a quote from the Boom source:

// Revision 1.11 1998/02/17 06:04:55 killough
// Change RNG calling sequences
// Fix minor icon landing bug
// Use lastenemy to make monsters remember former targets, and fix player look

And here's the reason why:

// killough 2/14/98: new field: save last known enemy. Prevents
// monsters from going to sleep after killing monsters and not
// seeing player anymore.

To summarize: Congratulations for finding a 7 year old gameplay enhancement. I don't think it's necessary to say that changing this back might break some DECORATE monsters.

[Phoenix9000]

And for 7 years I've been focused more on the Quake series, only going back to Doom to frag bots or scour the code for weapons data for my own project. Just call me Mr. Nitpicky Purist, but the monsters roaring after killing each other was always one of those touches I liked about Doom. While it may not kill the game, removing things like that does detract from it. I guess one person's "fix" is another's bug, but then I suppose not many people sneak around in Doom 1 anymore the way I do from time to time. I realize there's no intent or desire to change this behavior, but it's too bad you couldn't just cvar it.

[Anakin S.]

What if there could be a Victory state for decorate monsters which the monster performs after killing its target? This seems to be what the quake 2 tank uses. After it kills the player, it strikes the ground with its laser arm. Then you could have barons roar after killing their targets, and afterward they would continue to look for the player.

[Graf Zahl]

And for 7 years I've been focused more on the Quake series, only going back to Doom to frag bots or scour the code for weapons data for my own project. Just call me Mr. Nitpicky Purist, but the monsters roaring after killing each other was always one of those touches I liked about Doom.

And considering that ZDoom did even more changes to the enemy AI code it will never come back. It was a bug anyway.

While it may not kill the game, removing things like that does detract from it.

And cause problems with more complex monsters. Switching back to the spawn state can cause severe problems for some of Hexen's.

I guess one person's "fix" is another's bug, but then I suppose not many people sneak around in Doom 1 anymore the way I do from time to time. I realize there's no intent or desire to change this behavior, but it's too bad you couldn't just cvar it.

Sorry, it won't be possible. Due to some other changes a simple compatibility option won't help. If you need the original behavior so badly ZDoom isn't the right port for you anyway.

[Belial]

Use PrBoom. I've learned that backwards compatibility will never be an aim for ZDoom.

[HobbsTiger1]

\o/ for PRBoom. I used it for as long as I could and then, oh well. But ZDoom came along and its better

[Belial]

It's not if you're bent on classic gameplay and don't have a vanilla-doomable comp.

[HobbsTiger1]

@Belial Windows XP is a Vanilla compatable OS, in fact I cant think of anything that isn't (other than a really old clunker or an NT 4.0 machine, which is still really old).

[Phoenix9000]

No, it's alright. I work with game code all the time so I understand the technical limitations Graf is referring to, along with unwillingness to implement yet-another-feature-request, although I'd wager it's not so much a technical impossibility as opposed to involving a lot of work that could be better spent elsewhere. It's nothing I'll throw a fit over, I shoot down feature requests all the time myself.

[Belial]

@Belial Windows XP is a Vanilla compatable OS, in fact I cant think of anything that isn't (other than a really old clunker or an NT 4.0 machine, which is still really old).

The OS isn't everything. Even though I'm using Win98, my soundcard doesn't like some old dos games and unfortunately, Doom is one of them (then again, teh buggiest Daggerfall runs perfectly). Doom w/o sound doesn't make much sense.

Anyways, it's the first time I've heard XP is Vanilla compatible o_O.

[Anakin S.]

What if there could be a Victory state for decorate monsters which the monster performs after killing its target? This seems to be what the quake 2 tank uses. After it kills the player, it strikes the ground with its laser arm. Then you could have barons roar after killing their targets, and afterward they would continue to look for the player.

So what do you think?

[Graf Zahl]

Anyways, it's the first time I've heard XP is Vanilla compatible o_O.

The game itself runs but most modern sound cards refuse to work properly with such old games. I only can play them with sound completely off.

[HobbsTiger1]

@Belial Windows XP is a Vanilla compatable OS, in fact I cant think of anything that isn't (other than a really old clunker or an NT 4.0 machine, which is still really old).

The OS isn't everything. Even though I'm using Win98, my soundcard doesn't like some old dos games and unfortunately, Doom is one of them (then again, teh buggiest Daggerfall runs perfectly). Doom w/o sound doesn't make much sense.

Anyways, it's the first time I've heard XP is Vanilla compatible o_O.

Unless your extremely cheap (not saying you are) you can get a program called SoundFX that will make DOS programs think your sound card is one of those old Sound Blaster 16 Bit things, but I understand your point.

It is been of my notice that on todays systems ("todays" being Pentium II's and up)there are three things that really matter when trying to run Vanilla: OS, Sound Card, and Video Card (this is for SP of course). Your OS has to, well, has to NOT be NT 4.0 (I don't know about 2000). Your Sound Card has to emulate 16-bit sound in DOS (or you need SoundFX). Your video card must be capable of switching to the extremely low resolution of Vanilla (Since this is ZDoom's default it's not much of a problem. Processor and Motherboard don't matter much, as Doom "processes" like every other DOS program in the virtual 8086 area of RAM. And on that subject, I assume if you've got enough RAM to run ZDoom you've got enouh to run Vanilla.

Also Belial I have seen Vanilla run on Windows XP Professional once or twice with sound (and make a logical assumption it runs on Home), but before that I didn't think it would run on an NT based OS.

[Belial]

Heh, switching to 320x200 isn't a problem, switching back is. It usually hangs my system (Doom, Radix, Tyrian, Highway Hunter, anything). So SoundFX won't change much. But why are we talking about this? The whole point was that I don't need a Vanilla-doomable comp because there's PrBoom. I'll just wait until DosBox becomes less laggy. Even then I'll be using it for the Crusader games and not Doom.