top | item 44209497

What was Radiant AI, anyway?

234 points| paavohtl | 8 months ago |blog.paavo.me

118 comments

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flohofwoe|8 months ago

The closest thing we got to the idea of Radiant AI is probably Dwarf Fortress.

But entirely goal-driven (and thus unpredictable) game AI systems like this are usually at odds with story-driven gameplay where the outcome needs to be deterministic (or at least "winnable") and the player is the hero which the story is built around (while games like Dwarf Fortress don't have a pre-defined story, and also no player character to take care of, and the whole fortress being wiped out because of comically unpredictable events is a large part of the "fun").

programd|8 months ago

Another similar game to Dwarf Fortres is Song of Syx [0]. It's more accessible then DF and I think they can have up to 20,000 entities active in the world at a time. The world map is pretty huge, and the player gets to control a one group among many. Every entity in Song of Syx is individually modelled, though probably not in quite the details that DF is known for.

[0] https://store.steampowered.com/app/1162750/Songs_of_Syx/

gmueckl|8 months ago

That was also my thought. How does the world behave 100 hours into the simulation? If half the town residents have managed to get themselves killed by guards and some of the shopkeepers are gone, it's a bad outcome. Complex sims have emergent behaviors that are hard to tune.

The other thing is a bit more subtle. It's a big open world and all NPCs need to be active continuously for that sim to work. So you have a big N to squeeze into a tight per frame CPU budget. Also, things like path planning or object interaction only work if some information like object positions and pathfinding maps are kept in memory the whole time for the entire world. This sounds very challenging on a 2005 era PC.

PunchyHamster|8 months ago

In time since Oblivion we got games like Divinity: Original sin 1/2 where you can kill pretty much every character in the game and it will still be finishable.

The essential NPCs could also be flagged essential, or maybe have a variation of that flag where only way given character dies is if say 1/4 of the damage dealt to character is from player (so NPC can't accidentally kill important NPC basically).

Also, radiant AI can also just... not run on the plot significant NPCs.

Finally, Bethesda games aren't known from main story being the main selling point.

jadbox|8 months ago

Some of the Ultima games (and I think Morrowind) had a kind of simulated life routine: sleeping, opening shop, visiting family, exploring, etc.

nxobject|8 months ago

There's probably some mathematical way to express that... it'd be interesting to look at Todd's mythical "Radiant Economy", create a dynamical system model/game-theoretic mode, and try to prove that in the long run everyone doesn't end up broke or a millionaire.

kibwen|8 months ago

Regarding debunking the skooma merchant murder anecdote:

> The addicts live in a locked cabin, so it’s unlikely for the player to enter it unless they are specifically looking for it.

This is overlooking a crucial, obscure, and unintentionally hilarious detail: not all the skooma addicts are in the cabin! Out in the world are two NPCs who make a monthly inter-city trip to the den to get their fix. However, due to a bug where these NPCs are assigned to the wrong faction, they can't actually get through the locked door of the den, so they'll stand outside the door drinking skooma forever, unable to progress to the step of the AI package that would eventually return them home to their usual schedules, unless the player unlocks the door for them. https://en.uesp.net/wiki/Oblivion:Trenus_Duronius

paavohtl|8 months ago

Interesting detail, thanks for letting me now. I had a look at the AI packages of all three visitors (Gelephor, Gellius Terentius, Trenus Duronius) and at least in the base game (without UOP) none of them carry skooma nor are scripted to find it. So even though the game implies they are skooma addicts via dialogue & environmental storytelling, from a purely technical POV they are not addicts. Getting stuck outside the shack checks out, though I don't think faction membership is the reason for that — they simply don't have the key to the door.

weitendorf|8 months ago

After playing Starfield I don't really have any expectations for Bethesda to deliver on anything interesting anymore. The progression from Oblivion to Starfield has been one of becoming less like a small shop with character willing for its developers to take big risks with unique and intricate features, and more of trying to be a generic AAA studio that prefers predictable blandness. I don't think you can really hope that they'll magically return to making games the way they did 20 years ago.

They seem to now be under the mistaken impression that radiant AI is to get more content out of the game by implementing infinite permutations of simple quests, and that customers will think X things permuted Y ways is X*Y content and not just X+Y content. But the purpose of radiant AI was, I think, to make the world feel alive and even unique. Which means I really shouldn't even see every x in X or every y in Y.

If you want an interesting implementation of the same concepts as in Radiant AI I recommend checking out Dwarf Fortress. Every dwarf fortress world is essentially an entire history of thousands of radiant AI interactions up until you enter it, at which point your adventurer/fort becomes part of the world and continues the radiant interactions with its civilizations/wildlife/monsters/etc.

I think DF is probably the ideal existing game to considering adding LLM-characters and conversation to as a drop-in augmentation. DF already has the simulation and generation of realistic characters and stories working, but unfortunately it's very formulaic to interact with it as an adventurer. In that case the game actually is quite "alive" already, just without a voice.

Night_Thastus|8 months ago

To me, Starfield is a massive admission that either the developers don't understand what made their previous games work - or that no one will step in at a top level and prevent them breaking that core.

The modern TES games have been all about environmental storytelling, exploration, combat and crafting. All else is secondary.

Whether you like that focus or not is up to you, but that's the draw of games like Skyrim and FO4.

But Starfield completely broke it. They wanted hundreds of planets to explore, but the only practical way to do that is procedural generation. No one wants to explore procedural spaces. There's never anything interesting in them. You can't do environmental storytelling because that requires a human hand.

Due to engine limitations, making all the travel seamless was also completely impractical.

So instead of seeing a location and going "Oh man, I want to go there!", then just walking there encountering distractions on the way...it's Loading screen -> Loading Screen -> Loading screen -> Generic planet with nothing interesting to see.

How no one at a top level said "this can't work, the game's concept is bad, start over" is baffling. No one had a vision at the top level for how the game was supposed to work - or that vision was just wrong.

If Bethesda can't understand the fundamentals of their own best-selling game, I don't see how they can make a sequel.

ksynwa|8 months ago

Yes. IMO Starfield's biggest failure is in the creative department. It is not interesting at all (for me) in terms of things like writing and voice acting etc. It is not a technical problem that can solved by innovative game mechanics like a roided up version of radiant AI (whatever that is).

Games like RDR2 and Witcher 3 left such a mark on me becauss they had bold personalities. Starfield in comparison feels like corporate memphis despite a nice Nasapunk foundation.

thinkingtoilet|8 months ago

The funny thing about using AI to create an infinite amount of bland quests is that there is literally no audience for it. The people who play the game through once or twice aren't going to care about it and the people who want more of the game will download one of the thousands of mods created by the community. Oh, wow, you used AI to come up with a quest where I have to go to a cave and kill a creature. Amazing.

GrantMoyer|8 months ago

I think Starfield gets a lot more flak than it deserves. Yeah, compared to Fallout 4, where there's something hand placed to observe or interact with seemingly every 100 ft in any direction, the world feels barren. But I think the departure is intentional; Starfield felt much more like a spiritual successor to Daggerfall than to anything since Morrowind. Overall, I spent less time in Starfield than in older Bethesda titles, but I liked what was there, despite it being less dense, and I spent more time than I have in many other games.

Why should Bethesda have to refine the same exact formula over and over? That would just turn into what Ubisoft does with Assassins Creed, pumping out soulless entry after entry into the franchise. In other words, Starfield was Bethesda taking a risk and trying to introduce unique features rather than releasing yet another another predictable "Bethesda RPG".

sesm|8 months ago

* from Morrowind to Starfield

Oblivion was a big step back from Morrowind: generic art style, map markers, no deep story.

cynicalsecurity|8 months ago

Don't wait on Bethesda to deliver. Try Enderal. Your expectations will be fully met.

ModernMech|8 months ago

Games have a similar lifecycle to social scenes. Now and again, an amazing game comes along that captures the imagination of gamers. Usually it's made by really creative and innovative people with a clear vision and direction. Also these people usually have taste, which is a crucial element.

Their good taste attracts a bunch of early adopters, people with a finger on the pulse and who are eager to play and appreciate the game for what it is. But this interest attracts poseurs, people who play the game but just to say they are, to feel included and a part of something cool. There are far more poseurs than otherwise, so at this stage the scene can grow exponentially. This growth attracts vultures commoditize the scene in the form of penny pinching and "enshitification" through dark patterns. Monied interests strip out everything that made the game interesting and fun (because a good, fun experience isn't profitable), and then they milk it for everything it's worth until it's a dried corpse. These are the people who are driving the bad gameplay decisions and who aren't listening to the taste makers.

Usually in games this comes in the form of a pivot to MMOs. By that measure, TES died in 2014.

IMO this also applies to Final Fantasy (RIP 2010, plenty of new FF games but nothing that recaptured the magic of 6 and 7) and Warcraft (RIP 2004, no new warcraft games since).

jasonjmcghee|8 months ago

Maybe through a mod. Hard to imagine Tarn would have any interest involving LLMs.

Der_Einzige|8 months ago

The overwhelming majority of folks even here will not play DF. If you want them to play a DF like game, talk about rimworld please!

devstar|8 months ago

As a Bethesda fan (spending 1000s of hours combined in Fallout and Skyrim), I enjoyed reading this post. Especially liked the use of creating your own NPC to test the various scenarios. I just now started playing the Oblivion remaster for the first time and I find that I am liking the NPC interactions / liveliness a lot more compared to their later titles.

The one item that stood out to me was: "Todd’s mid-fight dagger acquisition Verdict: Impossible in the final game unless scripted to do so"

I do not disagree with the verdict for the final build of the game but I recall observing something similar in Fallout 3. I had stashed a mini-nuke launcher and ammmo in the Megaton player home. Some sort of conflict transpired (do not remember what exactly, perhaps I provoked an NPC for fun), I witnessed one of the town-folk run into my player home (in its own cell) and come back out with my weapon. It is possible with 1000s of hours in Bethesda games I am just mishmashing memories together but I am pretty sure this is what prompted me to eventually download a player home mod (and eventually learn G.E.C.K. by "remastering" it).

paavohtl|8 months ago

Thanks for reading!

It's an interesting anecdote, but from my understanding of the system that simply shouldn't be possible. Your house's interior cell isn't loaded into memory when you are outside in Megaton, so there's no way for the NPC to access your items. I think this fundamental limitation holds true for every version of the engine, from Morrowind to Starfield, but I'd be glad to be proven wrong with concrete evidence.

hyperman1|8 months ago

When I played gothic, I was in the wilderness and in the process of being killed by some beast. Completely unexpected, a core NPC (Lester?) joined the fight and slew it. It turns out, he makes a walk between 2 camps every day, and happened to be around just at the right time.

While already impressed by the AI, I was blown away by this l behaviour. He goes between 2 places that can't exist in RAM at the same time, and interacts with the world when it happens to pop into existence around him.

Radiant AI should and could have been like this.

Merad|8 months ago

Oblivion has multiple NPCs with complex schedules that involve travel between cities. And yes, you can run into them on the road. Best example is the countess of Leyawin, once a month she visits her mother in Chorrol (opposite side of the map) along with her personal guards and advisor.

paavohtl|8 months ago

Radiant AI does work exactly like that. The game keeps the global cell-level pathfinding graph in memory at all times, and uses it to simulate NPC travel outside of the loaded area.

nxobject|8 months ago

After hearing the "everyone pickpockets everyone and goes to jail and/or dies" anecdote for the "original" Radiant AI, I'm beginning to suspect that the following are incompatible:'

– there's always enough interesting characters to interact with to give quests etc.;

- live simulated world with emergent behavior that involves characters disappearing;

- no one enters or leaves town.

recursivecaveat|8 months ago

Honestly I think there is a fundamental incompatibility between: some sense of simulation or realism, and a high enough density of interesting events per character per hour to meet the player's entertainment expectations. A functioning society just can't supply enough arrests, trysts, bandit kidnappings, secret identities, feuds, marriages, etc etc, without rapidly tearing itself completely apart. There's a reason basically every TV show feels like it going off the rails after a few seasons: you can't lay rails in front of you as fast as episodes consume them. It only works at the beginning because you're borrowing against the stock of events that occurred in-universe before the show began.

Dwarf Fortress kindof solves this by zooming out to increase the character count, as well as the standard fantasy trick of super-charging the economic productivity of everything. Letting 1 dwarf feed 15 by working part-time on a 25 square meter plot of mushrooms helps a lot.

o11c|8 months ago

The "always enough interesting characters" problem needs to be solved by something along the lines of "if an important NPC dies, the role is passed to an heir". But ... also the world needs to be less murder-y, and (related) actually have a closed economy.

The article mentioned the problem of fitting audio on a single DVD (which would only be exacerbated by fallbacks, and no please don't consume my entire SSD) ... there certainly was a regression in video game creative dialogue when everything started to be voiced. And voice synthesis is an example of one of the rare problems that AI might actually be able to solve fairly reliably, though it's not clear if the jarring exceptions would be more of a problem outside the current utility problems. Though given that the individual input words should be known, probably just converting text to phonemes would suffice.

ednite|8 months ago

Interesting read. Got me thinking, I’d love to see what happens when modern AI meets open world simulation. Not just prettier graphics, but actual reasoning NPCs. Imagine arguing with a World of Warcraft innkeeper about the price of ale. Priceless.

dialup_sounds|8 months ago

Wiring a chatbot to dialogue is less interesting to me than the possibility of AI directing scenes and orchestrating reactivity across multiple characters. A reasoning model can ensure that the world responds to the player in a reasonable and narratively interesting way, without having to script everything or make individual characters particularly intelligent.

We're used to thinking of game AI as a property of the entity it's attached to (the NPC, the enemy, the opposing player) but an LLM can sit above that, more like a dungeon master.

Dzugaru|8 months ago

Not possible, because can't be guardrailed with 100% accuracy. You'll ask it something outside of the Warcraft world (e.g. US politics), and it'll happily oblige. I imagine NPCs will generate really weird immersion breaking stuff even if you cannot freeform interact with them anyway.

Not to mention the current token cost.

thrance|8 months ago

I enjoy getting my ale at the click of a button, and keep my arguing capabilities for stranger online.

There may be a place for AI driven games but there is literally no reason to shove it everywhere. Pre-written dialogue is much more enjoyable to engage with on the long term, contrasted with having to think about phrasing for an NPC that spouts generic fantasy speak.

anonzzzies|8 months ago

and the place where hallucinations can be a feature instead of a bug

ajkjk|8 months ago

I have remembered the phrase "Radiant AI" from the Oblivion Marketing when it came out, 2005ish I guess, when I was in high school. I'm glad it stuck with someone else as much as it did for me: the hype, the disappointment, but also the wondering what it could have been, because it sounded like a legitimately very-cool game feature except for the part where it didn't exist.

netruk44|8 months ago

What an amazingly well researched and interesting post. I’m very grateful to the author for having done the legwork to research all of this.

I loved how they were able to peel back the Todd Howard reality distortion field to really understand how Bethesda went from that famous E3 2005 demo to what we got in the end.

paavohtl|8 months ago

Thanks for your kind words! Researching and writing this consumed most of my free time for about two weeks, but I think it was worth it.

nxobject|8 months ago

> "Hail."

> "I have heard that the Nords of Skyrim have been warring with the Redoran of Morrowind."

> "It seems that these are turbulent times in the land of the Dunmer."

> "Stop talking!"

> "Take care"

YeGoblynQueenne|8 months ago

>> The technology powering this next generation title is doing so much more than simply making everything look great, it’s also changing the rules of how virtual game worlds function. As mentioned before, the area of Tamriel that is the setting for Oblivion is populated with 1,000 NPCs. Unlike current games, these characters don’t simply disappear once the player leaves the area, they exist 24 hours a day, seven days a week. Every character has its own virtual life and its own schedule to follow.

You know who really did this? It's a game called Rain World [1]. In Rain World, the world keeps turning when you're gone. Literally: predators and prey go about their way, chasing and fighting and eating each other, after you die. When you come back they don't respawn. The game simulates their actions while you're away and you meet them again in medias res, doing whatever they were doing while you weren't there.

And what was the reaction of the gaming public to that? A typical reaction on release was this article by Brendan Caldwell on Rock Paper Shotgun, whence I quote:

Modern platformers that want to be difficult have learned the value of a quick and nearby spawn. Fell into some spikes? Never mind, says the game, and one second later you are at the last brick wall you leapt from. The slugcat doesn’t get this treatment, instead it is transported back to the nearest save point, the last hibernation chamber. The things you have done to the environment have been undone, the parts of the map you revealed have been recovered in shroud. You are ten screens back from where you were, only now the predators and prey will be in different places.

(...)

The oddest thing about it is that, like the controls, this difficulty feels entirely deliberate. It is like Rain World wants to have the strength of difficulty we find in Dark Souls. But that classic of dying and re-dying had the impetus of soul currency, a sense of gambling, a sense of pace, and the relief of clever shortcuts with near-perfect geography. Not to mention the HUGELY SIGNIFICANT gesture of always putting the enemies reliably in the same place, like a solid, immovable set of spiky hurdles. You always had the means to overcome and defeat them. You just needed to learn.

https://www.rockpapershotgun.com/rain-world-review

In other words: "What? I can't just memorise enemies' positions so I can defeat them by muscle memory alone??? I have to think?? Each time?? During a game????"

:Throws controller:

Yeah, so much about AI simulating enemies that have an independent existence.

________________

[1] https://en.wikipedia.org/wiki/Rain_World

Mistletoe|8 months ago

When will we get games that actually do do this? It’s one of the things I’m actually excited about with AI.

jeroenhd|8 months ago

I'm not sure about the limits of the engine's complexity, but the game "shadows of doubt", a procedurally generated murder mystery game, has a giant sandbox with characters that have jobs, partners, visit restaurants, and more.

I don't think the NPCs can do more than a handful of actual actions, but the way you can find who a character met by watching the security tapes of a particular restaurant from a particular time because on of the bat's neighbours says "I saw this person here last night" when you ask about your murder victim is extremely impressive.

There is definitely a sense that you've seen everything after a while because of the limitations of procedural generation, of course, but a sandbox like that combined with scripted quests would make for some really fun gameplay outside of the main quest.

teamonkey|8 months ago

Honestly the big problem isn’t the tech. The AI techniques you use most often are decades-old and well-known, LLMs don’t really enter in to it except for generative dialogue.

The problem is that except for in a handful of cases the idea is often more appealing than the reality.

KaoruAoiShiho|8 months ago

The Sims, Crusasder Kings, the new inzoi games all have this.

dedicate|8 months ago

I don't actually want to have a deep, philosophical conversation with a blacksmith.

I just want to see that blacksmith close up shop early because he's feuding with the town guard, or give me a discount because his daughter just won the local archery competition. I want a world that reacts to itself, not just to me.

The goal shouldn't be to make NPCs that can pass the Turing test, but to make a world that feels like it has a pulse.

kjkjadksj|8 months ago

Do you really want that in a scrolls game though? I want the blacksmith to be first npc in the town, more or less always there, with 1 button on the dialog tree to get to the shop menu for me to unload an entire dungeon of loot onto this blacksmith. And he better have ore and leather strips.

TillE|8 months ago

Agreed, that's the real dream of open world RPGs: dynamic worlds. Perhaps modern AI techniques can help in that a bit, but what you really need is an incredibly intricate simulation.

deadbabe|8 months ago

It doesn’t need to be a deep philosophical conversation. You could be striking up a “buy now pay later” business deal or asking him to produce a specific type of equipment according to your specifications, etc.

Legend2440|8 months ago

>I don't actually want to have a deep, philosophical conversation with a blacksmith.

You didn’t read the article, that’s not what Radiant AI did. This is from twenty years ago and has nothing to do with LLMs.

supermatt|8 months ago

It’s entirely possible that Radiant AI in its entirety is actually in the original oblivion and the remaster.

It’s just that they either forgot to enable the build flag, or part of their production release is to pick a random commit as gold master.

As people had already parted with their money it’s been given the same priority as the game breaking bugs - which is to say it was left for the community to fix.

Maybe they will put out a “hotfix” in another 15 years to enable it.

I strongly believe that no bethesda employee has ever played a release version of their games.

paavohtl|8 months ago

Radiant AI is in Oblivion and every game they've made since then. There's nothing to enable. The issue is primarily with the game content; it's used all over the place, but in the final game it's not very impactful.