Radiant AI Quirks and Bugs

Phreddie · Post by **Phreddie** » Thu Mar 09, 2006 5:24 pm

It has been said that npc's can kill each other if certain qualifications are met, such as the npc's disposition towards each other drops so much that they literally hate each other. Wouldnt it be hilarious if you say, go to a major town (not a big city, just a large village) and find out that its gone?

This thread is just to post your questions about possible quirks in the Radiant AI system that could lead to hilarious if not devasting consequences.

fable · Post by **fable** » Thu Mar 09, 2006 5:55 pm

[QUOTE=Phreddie]It has been said that npc's can kill each other if certain qualifications are met, such as the npc's disposition towards each other drops so much that they literally hate each other.[/quote]

That's also a feature of Morrowind, but the PR is making a big deal about it, now.

In fact, there are several mods that do just that. One I've got adds thousands of NPCs in a couple of dozen professions to Vvardenfell, and you'll find guards attacking special thief assassins that stalk you in daylight.

REal953 · Post by **REal953** » Thu Mar 09, 2006 6:55 pm

[QUOTE=fable]That's also a feature of Morrowind, but the PR is making a big deal about it, now.

In fact, there are several mods that do just that. One I've got adds thousands of NPCs in a couple of dozen professions to Vvardenfell, and you'll find guards attacking special thief assassins that stalk you in daylight.[/QUOTE]

I think thats the one I dowloaded, it was cool but I had a lot of glitches. I think that my be a problem with the NPC's attacking each other in Oblivion. I can see it now, guards attacking anything.

fable · Post by **fable** » Thu Mar 09, 2006 7:05 pm

[QUOTE=REal953]I think thats the one I dowloaded, it was cool but I had a lot of glitches. I think that my be a problem with the NPC's attacking each other in Oblivion. I can see it now, guards attacking anything.[/QUOTE]

No, there were no glitches in Morrowind Comes Alive. It plays extremely well. As for NPCs attacking one another, the point about scripting is that you, as the scripter, determine who does the attacking, who are the targets, when they attack, where, how, for how long, etc. So long as the scripter is careful, there's no possibility of an accidental attack. And for guards to attack anything is out of the question, unless they're programmed to do so.

Problems might occur if there's a conflict with another mod, however. For example, if there's an event in which three guards attack all NPCs of a particular race on a certain day and another mod places an NPC of that race there first, the event could trigger ahead of schedule. But that's about it.

Phreddie · Post by **Phreddie** » Thu Mar 09, 2006 8:37 pm

Fable, I was more talking about if NPC A stopped and talked to NPC B and they got in an argument over differing views, they started to fight, friend sof A and friends of B joined in and all of Sudden Town of NPC A and B is gone. (It has been confirmed that Npc's can get into fight amongst each other, it couldnt happen in morrowind unless as you said it was scripted, this is completely random. It has also been confirmed that if you attack and NPC those who are 'friends' with him will come to his aid, unlike in morrowind were everyone jumped you at first.).

fable · Post by **fable** » Thu Mar 09, 2006 9:06 pm

[QUOTE=Phreddie]Fable, I was more talking about if NPC A stopped and talked to NPC B and they got in an argument over differing views, they started to fight, friend sof A and friends of B joined in and all of Sudden Town of NPC A and B is gone. (It has been confirmed that Npc's can get into fight amongst each other, it couldnt happen in morrowind unless as you said it was scripted, this is completely random. It has also been confirmed that if you attack and NPC those who are 'friends' with him will come to his aid, unlike in morrowind were everyone jumped you at first.).[/QUOTE]

It can't happen in Oblivion either, unless it's pre-scripted. In normal mode, NPCs will simply mill around and provide dialog options. They won't "do" anything. So if NPC A and NPC B decide to have at it, that will be because it's scripted, but it still won't involve anybody else in town--unless they've all been programmed to attack any NPC who attacks their friend.

ch85us2001 · Post by **ch85us2001** » Thu Mar 09, 2006 9:47 pm

No, I'm pretty sure it's been confirmed they can do all that. The whole "desirable rake" test. (the one where an NPC killed another because he wanted a rake REALLY bad, apparently.) I may be wrong though.

I want to figure out ways to turn the town against each other (Tamrielic Darth Sidious) :devil:

fable · Post by **fable** » Thu Mar 09, 2006 9:51 pm

ch85us2001 wrote:No, I'm pretty sure it's been confirmed they can do all that.

Never said they couldn't--only that there are a number of things that have to be programmed for it to happen. Enough, so that I can't really see it happening by accident. But of course, players are ingenious and will look for every way to mess up the code...so who knows? I guess we'll just have to wait, and see.

I want to figure out ways to turn the town against each other (Tamrielic Darth Sidious) :devil:

You would.

Phreddie · Post by **Phreddie** » Fri Mar 10, 2006 5:28 am

Fable your missing me here, man I swear you get older by th day...

NPC's can do that, they stop and have conversations of their own accord depending on wether or not they like the person or have anything to talk about. Also, other events could trigger the mayhem, such as soemthing like the Desrable Rake Test, although I doubt it would be with a rake. Say NPC A is hungry, but he is poor and cant afford food, nor can he grow it, so he steals it from NPC Butcher, NPC Butcher sees him, and instead of calling the gaurds attacks NPC A, there are a multitude of scenarios where NPC's will go ape on each other, thats the point of Radiant AI, just about anything can happen.

Any one think of another little screw up that could occur?

fable · Post by **fable** » Fri Mar 10, 2006 7:27 am

Phreddie wrote:Fable your missing me here, man I swear you get older by th day...

Yes, and you appear to be getting even younger.

NPC's can do that, they stop and have conversations of their own accord depending on wether or not they like the person or have anything to talk about. Also, other events could trigger the mayhem, such as soemthing like the Desrable Rake Test, although I doubt it would be with a rake. Say NPC A is hungry, but he is poor and cant afford food, nor can he grow it, so he steals it from NPC Butcher, NPC Butcher sees him, and instead of calling the gaurds attacks NPC A, there are a multitude of scenarios where NPC's will go ape on each other, thats the point of Radiant AI, just about anything can happen.

I think you're missing the facts that 1) all this behavior has to be programmed in, and 2) it's already possible in Morrowind. The development team simply didn't make much use of it. They are making more use of programmed behaviors in Oblivion, but it's really jumping the gun to say that there will mass slaughters because of bad programming, which will have drastic consequences impossible before. It's been possible, and even in Oblivion, it isn't the kind of thing that can slip under the wire. Do you really believe the developers are going to release the title with such massive bugs that entire cities vanish because of some scripting flaw that has one NPC attacking another?

Speaking as someone who worked on game code of that sort in a MMORPG, you work all possibilities out in advance, then you program it in development mode, then you test it. I can't see Bethsoft releasing a product so amateurishly built that it has such massive scripting flaws in place.

Rookierookie · Post by **Rookierookie** » Fri Mar 10, 2006 8:24 am

Won't it just be a matter of scripting only the guy-in-the-street to have random behaviour, and excluding important people such as shop-keepers, healers, and quest-related people?

fable · Post by **fable** » Fri Mar 10, 2006 9:10 am

[QUOTE=Rookierookie]Won't it just be a matter of scripting only the guy-in-the-street to have random behaviour, and excluding important people such as shop-keepers, healers, and quest-related people?[/QUOTE]

No, because there's no "random" option. If you leave the scripting alone, they stand there. Just as they did in Morrowind.

Rookierookie · Post by **Rookierookie** » Fri Mar 10, 2006 9:33 am

"Random", as in "won' just stand there doin' nothin' ". Don't take it literally.

fable · Post by **fable** » Fri Mar 10, 2006 9:46 am

[QUOTE=Rookierookie]"Random", as in "won' just stand there doin' nothin' ". Don't take it literally.[/QUOTE]

But we're discussing programming, and everything *is* literal, in programming. You just can't script an NPC to "do anything but stand there." You have to give it explicit directions. The random behavior you mention isn't an option: it isn't possible for NPCs in MW (and presumably Oblivion) to be directed to do whatever they want. You can give them choices, but you have to literally state all the choices, and you see the results.

So if you direct NPC A to do any of 8 possible actions, and 1 of those actions is to attack the nearest NPC, you, as the programmer, already know this in advance. You've coded it in, and you also get to see it repeatedly in testing until you're sick of it.

This isn't something that could accidentally happen, and it hasn't, in MW, where there were a far greater number of NPCs.

But if you want to believe otherwise, go ahead. The game will be out in more than a week, and you can spend time looking for towns that are decimated, just like that. Better yet: you can rescript the actions of NPCs to do it, yourself.

ch85us2001 · Post by **ch85us2001** » Fri Mar 10, 2006 10:38 am

I see Fables point now.
NPCs cant kill someone just because they feel like it, they have to be scripted to respond to other stimuli.

*cough* I was wrong.

I still think I can turn the town against itself!

Acleacius · Post by **Acleacius** » Fri Mar 10, 2006 6:45 pm

Bethseda specificly programmed preventions to this very thing, in the Released version of the game.
They have even said they removed random behaviors to prevent game breaking situations.
Of course you can open up the paramiters to alow NPCs to fight thru Ramdom/Scripted behaviors.
Bethesda has specificly said that you could specificly program an single NPC to go loot/kill a whole town and put the loot in a specific location/possible give to the PC (cant recall exactly) with absolutly no negitive consequenses to the PC.
How ever such Behavior modifcations can break the MQ/SQ of the game.

Tetsumaru · Post by **Tetsumaru** » Fri Mar 10, 2006 11:02 pm

"Our new Radiant AI system allows for full 24/7 schedules for every NPC and they also think on their own. We give them general goals to accomplish and the NPC figures out how to accomplish it. Radiant AI allows us to have that kind of advanced behavior on a massive scale."

they dont have to be specifically programmed to kill something in oblivion, that is the point of the Radiant AI, so yeah they can kill each other, and its *possible* (highly unlikely, unless you mod them to be a lot more agressive or something) that all the people in a town will kill each other until theres one insane guy left eating a dead guys neck.

fable · Post by **fable** » Sat Mar 11, 2006 12:10 am

Tetsumaru wrote:they dont have to be specifically programmed to kill something in oblivion, that is the point of the Radiant AI, so yeah they can kill each other,

Nobody has said one NPC couldn't kill another. But an NPC has to be programmed to kill. You can't just tell an NPC, "Figure out how to get past the lion." The NPC has to be first given the code that allows it to 1) walk, 2) run, 3) kill, 4) seek alternate methods of transportation in the area. The code has to be there. If there isn't any code that's been programmed in for killing, it's not going to kill. When the developer writes, "We give them general goals to accomplish and the NPC figures out how to accomplish it," they mean, "An NPC can be programmed to select for itself one of several pre-programmed choices based on a set of pre-programmed priorities we've given it." I've done this kind of coding for years, and though I haven't worked for Bethsoft, I'm pretty sure I know how it's done.

and its *possible* (highly unlikely, unless you mod them to be a lot more agressive or something) that all the people in a town will kill each other until theres one insane guy left eating a dead guys neck.

It's only possible if it's been programmed into the code. If it isn't, it won't happen, and we both know the developers aren't going to build a city, with all the resources of time and effort that takes, just to stick in some bit of scripting that allows for one guy to end up killing everybody else--unless it's a deliberate quest for you to stop a massacre. If you or anybody else disagrees with the fact that the code has to include the action to kill, then fine: wait a week, play the game, and show me where I was wrong.

Until then, any discussion of Radiant AI's "bugs" or "quirks" is nothing more than assumptions about a product that hasn't been released.

fable · Post by **fable** » Sat Mar 11, 2006 1:17 am

ch85us2001 wrote:I see Fables point now.
NPCs cant kill someone just because they feel like it, they have to be scripted to respond to other stimuli.

Yes, that's pretty much the size of it. You can write PR that claims your NPCs act in a "random fashion," but it's only pre-programmed randomness.

It's what's called rules-based AI, or sometimes pseudo-AI: it doesn't really involve any learning, so (by some definitions) it's not really intelligence. It's been around for years, too, not just starting with Oblivion.

For example, when I was working for one of the better MMORPGs out there, we had several kinds of values with numbers we could use to control AI behavior, and simulate randomness. We could make an NPC smarter--meaning it gave a higher personal value to what was the best possibility it had available--or a lower one. We could add all sorts of conditional IF/THEN clauses to its behavior, so that the priorities for a healthy NPC might change if it was wounded; or attacked by a level 3 player, vs attack by a level 30 player. We could make it launch into different dialogs if approached by a warrior, or a cleric. I built an NPC once that insulted any profession approaching a manhole cover, but would allow entrance to any thief over the level of 19, and turn away any thief under that level with kind words. When not engaged in dialog, he went through a series of more than a dozen "randomized" activities, based on local weather, nearby threats, etc.

But it was all pre-programmed. NPCs don't think for themselves. If they're going to kill, it's the developer that made them do it.

I still think I can turn the town against itself!

LOL! I'm sure you're going to try, too.

Gaal Dornik · Post by **Gaal Dornik** » Sat Mar 11, 2006 2:30 am

[QUOTE=fable] You can write PR that claims your NPCs act in a "random fashion," but it's only pre-programmed randomness.

[/QUOTE]
Thats just hairsplitting. Ofc they have to be programmed, they're programs after all and not humans, but i think what others are saying is that these scripts can fight each other w/o any additional script, not requiring the presence of a PC char, totally on random. a=10*RND; if a=1, then FIGHT.

Only make sense in real life, where you come to some village and half of the ppl are dead, cause they had a small massacre there

I think tho, most ppl would be seriously annoyed(i know i would), if an NPC of some value would be killed, preventing questing. So the reality would probably be that only the useless villagers can be killed. And their houses will be filled with new NPC. Again, it only adds depth to the game, where you come to a village and see dead body, and ppl investigating and discussing. interesting.