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See http://memeticai.org/ for some work that was done for BioWare's Neverwinter Nights series. Interesting stuff, and pretty promising, but *hard*. The great thing about using NWN as the game is that there is a very accessible scripting language available, so the only thing you need to concern yourself with is the AI itself. It might not be the approach you want to take, but it does illustrate the potential for building AI in an RPG.

AI for NeverWinter Nights

Some of you might be aware that the PC/Mac/Linux Game Neverwinter Nights includes a toolset with a C-like scripting language that allows users to code the behavior of characters in a game---not just for combat, but generic interactions as well.

BioWare, the developers of the game, are known for the imaginative story lines in their Star Wars: Knights of the Old Republic and Baldur's Gate series. However, by their own admission, they never have as much time as they want to work on creature AI. In Neverwinter Nights, this shortage of time resulted in a number of unfortunate situations during game play. For example, friendly characters would waste powerful spells on pitifully weak enemies; or they would continually attempt to cast spells in close hand-to-hand combat, not realizing that this gives the close-by enemy countless opportunities to tear them into pieces, and that pulling out that dagger in their backpack might be a better idea. Especially sad were near-death enemies who would try to heal themselves with woefully inadequate healing spells (in RPG talk, down 80 hit points and casting cure minor wounds).

Luckily, the toolset allowed a number of us to code improvements to NPC behavior. I was one of them, starting the Henchman Inventory and Battle AI project, now lead by Tony K. The focus of our project was immediate improvement of game play. An even more impressive community is the Memetic AI group. These folks are putting together a full package of complex behaviors for an entire world, from peasant farmers to fearsome dragons. Impressive stuff.

I would rather a company aims for greatness and comes out with a few nitpick-worthy bugs, than have it aim for mediocrity and succeed.

I think many people would disagree with your charge that BioWare has poor support. Their developers post frequently (around 5 times or more per day) in their forums, discussing everything from plot points to scripting to technical issues. They are very friendly and quick to answer questions. Do they sometimes have a messed-up priority list for bug fixes? Perhaps (the shield-wielding monk bug comes to mind), but overall these are minor points when you take into account how ambitious they are. And they are willing to tell you repeatedly (as opposed to just ignoring you) that they believe your bug is not important enough to fix yet.

An example of BioWare's excellence is the NWScript language, which, though largely undocumented and requiring a little bit of adventure to get working, is very flexible and full of features. No other $30 game building tool has that kind of complexity. It is powerful enough that very sophisticated creature AIs have been built with it in the user community.

As far as single player games go, few RPG fans would deny the excellence of the writing in BioWare's RPGs (those that do deny it, though, do so with fervor). Both KoTOR or the Baldur's Gate saga offer a satisfying and deep single-player experiencee. Some may bring up Black Isle's Planescape: Torment as a game that exceeded those two in depth, but remember that Torment would not have been possible without BioWare's Infinity Engine---another great technical innovation on their part, one that (uselessly) made Interplay a good fraction of their profits.

And now, Black Isle Take 2 owes its existence to BioWare---both with KOToR 2 and NWN 2. Six years ago, Black Isle gave BioWare a chance---and now the tables are turned. I think it's great to see a friendship like that, even from a distance.

And yes, the NWN single-player experience wasn't up to par with the BioWare storytelling standard, though they claimed it was. Let's hope Obsidian does a good job with respect to that.

Memetic AI for Neverwinter Nights. This stuff is pretty innovative, at least in theory, and I hope they eventually get to the 1.0 phase with more than just the groundwork done. The approach it takes might be an interesting, even intuitive, way for building the NPC/creature behavior from ground up.

This implementation is written in NWScript and is designed to run on a stand alone server using Bioware's NeverwinterNights game platform. It is distributed as a set of scripts that can be imported into Bioware's toolkit. It does not require a database, or hacks to the original game.

Links:

• Project Homepage
• Download Latest Release, Here
• API Reference Manual
• Example XML Debug Log

Major features include:

• Complete implementation of classes and (multiple) inheritance for NWScript
• Full support for automatic preemption, and resumption of actions, without losing state
• Response-tables, child behaviors, decaying variables.
• Non-linear time to ease the handling of real-time to game-time coding.
• Trails & landmarks, a resuable path system based on NPC preference
• Non-polling solutions for points of interest observation
• Complete asynchronous messaging, direct to NPC or via channel subscriptions
• Completely modularization of response, behavior, and message handlers.
• Chains of actions, sequence can resume or restart based on preemption
• Sample code, forums, documentation, and an active friendly community.

-W. Bull

This implementation is written in NWScript and is designed to run on a stand alone server using Bioware's NeverwinterNights game platform. It is distributed as a set of scripts that can be imported into Bioware's toolkit. It does not require a database, or hacks to the original game.

Links:

• Project Homepage
• Download Latest Release, Here
• API Reference Manual
• Example XML Debug Log

Major features include:

• Complete implementation of classes and (multiple) inheritance for NWScript
• Full support for automatic preemption, and resumption of actions, without losing state
• Response-tables, child behaviors, decaying variables.
• Non-linear time to ease the handling of real-time to game-time coding.
• Trails & landmarks, a resuable path system based on NPC preference
• Non-polling solutions for points of interest observation
• Complete asynchronous messaging, direct to NPC or via channel subscriptions
• Completely modularization of response, behavior, and message handlers.
• Chains of actions, sequence can resume or restart based on preemption
• Sample code, forums, documentation, and an active friendly community.

-W. Bull

This implementation is written in NWScript and is designed to run on a stand alone server using Bioware's NeverwinterNights game platform. It is distributed as a set of scripts that can be imported into Bioware's toolkit. It does not require a database, or hacks to the original game.

Links:

• Project Homepage
• Download Latest Release, Here
• API Reference Manual
• Example XML Debug Log

Major features include:

• Complete implementation of classes and (multiple) inheritance for NWScript
• Full support for automatic preemption, and resumption of actions, without losing state
• Response-tables, child behaviors, decaying variables.
• Non-linear time to ease the handling of real-time to game-time coding.
• Trails & landmarks, a resuable path system based on NPC preference
• Non-polling solutions for points of interest observation
• Complete asynchronous messaging, direct to NPC or via channel subscriptions
• Completely modularization of response, behavior, and message handlers.
• Chains of actions, sequence can resume or restart based on preemption
• Sample code, forums, documentation, and an active friendly community.

-W. Bull

This implementation is written in NWScript and is designed to run on a stand alone server using Bioware's NeverwinterNights game platform. It is distributed as a set of scripts that can be imported into Bioware's toolkit. It does not require a database, or hacks to the original game.

Links:

• Project Homepage
• Download Latest Release, Here
• API Reference Manual
• Example XML Debug Log

Major features include:

• Complete implementation of classes and (multiple) inheritance for NWScript
• Full support for automatic preemption, and resumption of actions, without losing state
• Response-tables, child behaviors, decaying variables.
• Non-linear time to ease the handling of real-time to game-time coding.
• Trails & landmarks, a resuable path system based on NPC preference
• Non-polling solutions for points of interest observation
• Complete asynchronous messaging, direct to NPC or via channel subscriptions
• Completely modularization of response, behavior, and message handlers.
• Chains of actions, sequence can resume or restart based on preemption
• Sample code, forums, documentation, and an active friendly community.

-W. Bull