Session Description For some time, the industry has been exploring how to effectively manage the complexity of multiple story arcs, contextually appropriate character behavior, and yet still maintain an over-arching ebb and flow of tension and drama. In their quest, writers and designers have started looking to AI for solutions to these problems. Additionally, many techniques that are already being used in interactive drama can be used to augment traditional games. Through three short lectures, this session gives examples of ways that AI can enable the design and implementation of branching narratives, dynamic adaptive dialog, interactive storytelling, and drama management.
Idea Takeaway The attendee will be presented with a number of examples of how AI techniques have addressed the needs of dynamics, interactive storytelling in games.
Session Description We asked designers from all across the industry to answer a questionnaire of probing - and even outright crazy questions. The intent was to get their heads and assemble a sort of wish list. We then present their answers to a panel of top-notch AI designers and programmers and ask them... how would you go about granting this wish? In what promises to be the most forward-looking session of the AI Summit, this panel should give us all a look into not only what the designers would like in their games, but some ideas on how to address the difficult obstacles in AI.
Idea Takeaway An impression of how much AI technology can accomplish, an insight into the technical design process of experienced developers. This session should be kind of fun and wacky!
Session Description In the past 30 years, game graphics have progressed to the point where still shots and cutscenes can often look extremely realistic. However, as soon as characters act in the world, that sense of believability is often broken. The characters no longer seem alive. Much of the impression that something is alive comes from minutia such as what they look at, how they move, and what they do when they aren't doing anything important. This session examines this phenomenon and gives concrete examples of how to improve the feeling of aliveness in game characters.
Idea Takeaway Attendees will see how including subtle details in the behavior can increase the believability of game characters.
Session Description While there are many versions of post mortem analyses in the game business, sometimes a broad brush approach doesn't highlight what the truly interesting nuggets are. In this session, we asked three AI programmers for recent games (Killzone 2, Brütal Legend, Dawn of War 2) to specifically address some unique challenges they faced in the development of their respective titles. They will describe what the challenges were, how they often arose from design decisions that pushed the boundaries of the typical AI comfort zone, and how these challenges were overcome.
Idea Takeaway The attendee will see examples of creative solutions to AI design problems - and potentially come away with a sense of how stepping outside a comfort zone is not necessarily dangerous.
Speaker: Steve Rabin (Principal Software Engineer, Nintendo of America), Kevin Dill (Software Engineer, Lockheed Martin), Brian Schwab (Senior AI/Gameplay Engineer, Blizzard Entertainment) Date/Time: TBD Experience Level: Intermediate Summit: AI Summit Format: 60-minute Lecture
Session Description AI programmers rarely use a pure architecture such as a State Machine, Planner, or Behavior Tree in isolation. Rather, several symbiotic architectures are mashed together, resulting in an overall architecture that is unique and powerful in its own way. This lecture is designed as a series of three mini-lectures where you will hear about several mashed up AI architectures along with intriguing lessons and insights.
Idea Takeaway Insight into the pros, cons, and subtleties of combining various AI architectures.
Session Description Over the last few years, various forms of behavior trees (BTs) have become the standard in industry. Since flexibility and customization are arguably the main strengths of BTs, they can be implemented in many ways. This set of short presentations will show how other developers are using them in practice. The presenters will show what developers can do to make behavior trees more designer friendly and easier to interact with via script. The session also shows implementation techniques to help keep AI code decoupled from the game logic and improve performance.
Idea Takeaway This session will explain different ways programmers can leverage BTs in their games. The attendee will see how various styles of behavior trees are used in practice to address many different problems.
Session Description Often one of the most important issues an AI programmer needs to address is the decision of which architecture to use. This choice lays the foundation for the rest of the project both enabling and limiting choices down the road. With myriad (and even conflicting) pro and con arguments for all the major AI architectures, it can be difficult to determine which one is right for a given project. This panel approaches this issue from a unique perspective. With one person acting as an advocate for each of the popular AI architectures, the panel will be presented with hypothetical game examples and asked to explain why their method is the right tool for the job and why others are not.
Idea Takeaway While this session is likely to get playfully adversarial, the attendee will be given not only a better understanding of the pros and cons of each of the types, but witness some of the thought processes that must occur when deciding on an AI architecture.
Session Description Typically, the 'next big thing' in AI comes from tireless research and experimentation. This session will feature many interesting and experimental working game AI prototypes from both industry and academia, all demoed live on stage. This promises to be a very inspirational and thought-provoking session with many presenters on-hand to show their creations and innovations.
Idea Takeaway Attendees will see a variety of new and different experiments and perhaps the 'next big thing' in AI. Prepare to be inspired to push the boundaries of traditional game AI!
Session Description The 'if/then' statement has been the workhorse of decision modeling longer than digital computing. Unfortunately, the harsh transition from yes to no often expresses itself through behavior in ways that are just as harsh. Utility theory has roots in areas such as psychology, economics, sociology, and classical game theory. By applying the science of utility theory with algorithmic techniques such as response curves, population distributions, and weighted randoms, we can improve the modeling of the underlying brain of our agents, broaden the potential decision space, and even manage edge cases that other decision systems stumble over.
Idea Takeaway This lecture explains the underpinnings of utility theory, and shows concrete examples of how to leverage it using the power of other algorithmic techniques regardless of the overall structure being used for the agent AI.
Session Description Small games have small budgets and short, iterative release cycles. But they still need great AI, only cut to size. This session presents first-hand experiences with successfully creating AI for a variety of those kinds of games. We will address the limitations faced by small budgets and present some useful tips from the trenches that will allow you to maximize the bang for your AI buck.
Idea Takeaway This session will show you how to deliver a working AI within a tight deadline using minimal manpower. It will also show you examples of simple approaches that actually add value to the game. Finally it will demonstrate that it is possible to start small and improve over time.
Microtalks - AI Devs Rant! Speaker: Borut Pfeifer (Freelance Game Programmer/Designer, Plush Apocalypse Productions), Dave Mark (President and Lead Designer, Intrinsic Algorithm), Adam Russell (Games Studio Manager and Lecturer, University of Derby), Kevin Dill (Software Engineer, Lockheed Martin), Steve Rabin (Principal Software Engineer, Nintendo of America), John Funge (Head of Game Platforms, Netflix) Date/Time: TBD Experience Level: Intermediate Summit: AI Summit Format: 60-minute Lecture
Session Description Sometimes things just need to be said. Saying them out loud in a room filled with (hopefully) like-minded people just makes it all the more interesting and cathartic. Seven AI developers from all corners of the industry will deliver quick, to-the-point rants about what's on their mind. Topics include AI design and programming, working with other portions of the dev team, working with academia, the perception of game AI by the public, scripting languages, and even those scary floating point numbers! Whoever said AI programmers only sit with their heads down over their keyboards?
Idea Takeaway Find out what's on the minds of AI developers in a fast-paced, fun, yet hopefully not controversy-rife session!
Session Description In recent years, there has been an increase in the number of available AI middleware products designed to streamline common development techniques. Their reception by the industry has been spotty, however. While there are some success stories and some tales of horror, many studios and individual developers still eye AI middleware with a mixture of curiosity and suspicion. This four-person panel, comprised of people whose experiences and opinions are spread across the spectrum from pro to con, will share their rationale for why existing middleware is good or bad and what changes future products could make to become more appealing to developers.
Idea Takeaway The attendee will hear real stories of how the use of AI middleware has hurt or helped development projects.
The GDC folks have put up the main page for the AI Summit at the 2010 GDC. This year, I am listed as a Summit Advisor alongside Steve Rabin. While I helped out a lot last year, I wasn't listed as an official advisor. That makes for a wonderful honor. I'm so pleased to be working with all the great people in the AI Game Programmers Guild to put this event on.
Takeaway This lecture shows examples of some of the aspects of PvP games that are attractive to players, the AI techniques that can be used to replicate them, and the effect that inclusion of these aspects can have in an MMO environment. The attendee will leave with a variety of concepts that can be included in their own MMO designs.
Session Description Historically, PvE AI in MMOs has been a straight-forward affair. While this leads to predictability, it also leads to monotony. In online, team-based PvP games, however, much of the attraction is the dynamic nature of the engagement that necessitates that players read, communicate, and react appropriately to changing, even unexpected actions of their enemies. By leveraging more advanced techniques that are becoming common in FPS, RPG, and RTS games, the AI in MMOs can be designed to provide some of the more attractive and engaging elements of PvP games. This, in turn, can lead to more involved team play, greater replayability, and an increased sense of community in the game.
I will be speaking at the 2009 Austin GDC, September 15-18. Rather than the broad-based coverage of the GDC, the Austin GDC is more tailored to online games. In that vein, I will be doing a 1-hour lecture entitled "Cover Me!: Promoting MMO Player Interaction through Advanced AI".
Well, I'm back and somewhat recovered from GDC. (It always helps to have a day of downtime built into the end of the week.)
From the comments that I and the rest of the participants received, the inaugural AI Summit was well received. I know that all of us were very pleased in not only the presentations that we each delivered but in all of the other ones as well. Apart from a false start at the beginning due to my laptop being under the proverbial weather with a virus, the rest of the two days went off smoothly.
I will post more on my reflections on each of the Summit sessions throughout the week. I did want to touch on a couple of high notes, however. We were very proud (as a group) to be able to deliver such a wide variety of topics. From animation to pathfinding to behavior to knowledge representation to layered goals and multi-threaded architecture, we hit a lot of the key topics. I think this was one of the comments that I heard the most... that there was a little bit of everything. Additionally, many people commented on how we mixed some past techniques with cutting edge stuff and then even some blue sky ponderings ("Human AI" and "Photoshop of AI". Additionally, people liked the sessions that weren't specifically technical such as the one on how to get along with designers.
For those that want to take a look at one man's views on it, Dan Kline did another of his "live blogging" exercises over at his pad, Game of Design. (Day 1 | Day 2)
In other GDC news, After the Summit, much of the week was anti-climactic. There were the 3 normal AI roundtables as well as one run by Alexander Nareyek. I will be posting pictures and audio from the roundtables on this page. You can also check out last year's stuff here. Eventually, I will have the pictures up from the AI Game Programmers Guild dinner (Sunday) and the regular annual AI Programmers Dinner (Friday) up as well. (Once I saw how dedicated to taking photos Petra Champandard of AIGameDev was, I figured I would let her do most of the shooting. I will link to those pictures as they become available.
Other than that, I only went to three sessions - one of which could actually be co-opted into an AI session. It was on balancing multi-player games. I figure this is an important facet of constructing AI as well for obvious reasons. I went to a roundtable hosted by Ben Sawyer about exploring emerging markets in games.
Peter Molyneux's lecture on how Lionhead explores experimental stuff was surprisingly lame for a Molyneux talk. I was just really hoping to see more of where they were going right now. I thought it was going to be a sneak peak session. (I should have suspected something when his PR handler was nowhere to be seen.) The only amusing moment was when he almost let out the name of the project... although it is likely no one would have gotten much out of simply a name. Oh well.
I did spend a lot of time on the Expo floor. Much of that time was spent nosing around my publisher's booth. I guess I sold quite a few books. The GDC store sold out of the 12 that they brought. Additionally, my publisher sold quite a few from their booth. Many of those sales happened while I was there. It took me by surprise to have people ask me to sign their copies. To be honest, it was more of an honor for me to be asked than I figure it was for them to receive a little of my ink. All I asked of them was to post a review out on Amazon when they got done. That would mean a lot to me (and the other people who might be interested in buying it).
Anyway, I plan on writing a bit more after I finally get my laptop cleared up. (Not looking good right now.) If you are coming into this post directly, you may want to check the tags below to see if I have written anything further about the Summit or GDC 2009.
I have been busily preparing all sorts of stuff at the last minute for the upcoming AI Summit at GDC. Having been involved since the initial discussions started at the last GDC, it has been interesting watching it grow.
The Summit is being put on by the newly formed AI Game Programmers Guild. As such, there are plenty of really sharp people involved. What was very striking, however, was how many times we all made comments expressing how interested we were in going to each others' sessions! Theoretically, we would put this Summit on for our own benefit even if there were no attendees at all! (Although I believe that the GDC folks would not be terribly pleased by that prospect.) Seriously, we could easily have filled the entire week with the information that we wanted to exchange I, for one, know that I will be at every single AI Summit session with rapt attention. I am even looking forward to hearing what my own co-lecturers, Phil Carlisle and Richard Evans, have to say in our session, "Breaking the Cookie-Cutter: Modeling Individual Personality, Mood, and Emotion in Characters"... and I have already looked at their slides!Â
One takeaway from that observation is that we will be talking about a lot of really nifty AI stuff. That much is obvious. Another takeaway, however, is that none of us... even the alleged "experts"... knows everything there is to know about AI. We all want to experience, learn, and expand. That desire comes from the somewhat discomforting awareness that there is a vast expanse of potential laid out before us. As the saying goes, "the more I learn, the more I learn how much I have to learn!"Â
I think that will be the underlying theme next week... not just at the AI Summit, but at the entire conference. Sure, there are students and... *ahem*... n00bs at the conference, but there are plenty of seasoned veterans sitting in the audience rather than standing behind the podium or sitting at a panel table. Why? There is plenty more we can do to advance ourselves and, by association, our trade.
The author is not alone... many players want what he lists here. And they are getting rather vocal about it. I'm just not so sure that the game companies and the publishers "get it" yet.
I took a moment to assure him that we, as AI programmers, hear his plaintive cry. This, my colleagues, is why we formed the AI Game Programmers Guild and why we are holding the AI Summit at GDC.
CMP/Think has posted more of the sessions for the GDC AI Summit that I am part of along witht he AI Game Programmers Guild. You can find the current list of sessions here. Both of my primary sessions are up now as well as my bio for what that's worth.
Session Description: AI characters can be beautifully modeled and animated, but their behavior rarely matches their life-like appearance. How can we advance the current state of the art, to make our characters seem more believable? What kinds of human behaviors are still missing in our AI, how can we implement them, and what challenges stand in the way? This session will discuss practical approaches to pushing the boundaries of character AI, past successes and ideas for the future, with an experienced panel representing a wide range of perspectives and games.
Date/Time:Tuesday (March 24, 2009) 9:00am — 10:00am Format: 60-minute Lecture Speakers: Richard Evans (Senior AI Engineer, Electronic Arts), Dave Mark (President and Lead Designer, Intrinsic Algorithm), Phil Carlisle (Game Programmer and Researcher/Lecturer, University of Bolton)
Session Description: As game characters engage in deeper interactions with the player, subtlety of behavior becomes more important. However, in worlds that feature hundreds of characters, the homogeneous 'cookie-cutter' approach of modeling those characters becomes evident, leaving the world feeling repetitive and shallow. Everyone acts the same. Using examples from games such as The Sims 3, we will show how characters can be algorithmically endowed with distinct personality differences so that every one acts as an individual. We will also explore how personality, mood, emotion and other environmental factors enable individual characters to select from a wide array of context-appropriate choices and actions. We conclude with how these behaviors can be expressed through animation selection so as to be more engaging and immersive for the player.
For those of you that are planning on heading to GDC, make sure that you get a pass that allows you to attend the Summits and Tutorials.
Ok... I've known about this for about 6 months (since I was in on the original planning phases) but, because things are finally official, I figure it is time to make the announcement here.
The new AI Game Programmers Guild--of which I am a founding member--is putting on a 2-day AI Summit at the 2009 Game Developers Conference. We have a lot of great people putting together 14 hours worth of lectures and panels on the current state of game AI as well as our vision of its future.
All in all, the AI Summit is going to be a spectacular event. We are figuring that it will become a yearly fixture at GDC. I am honored to be a part of its inception.
Is it possible for an AI to be both "good" and "fun"?
Take the time to jump on over and read it... and then comment either here or in the excellent AI forums there. (Forum registration may be required to comment... but then if you are an AI programmer, you need to be involved over there anyway!)
2008 AI Programmers' Dinner - Neil Kirby's Monologue
Not really all that tasty as an AI bit, but relevant nonetheless. I just uploaded Neil Kirby's opening of the 2008 AI Programmers' Dinner at the GDC. There are a couple of notes from it... he talks about the Eric Dybsand Scholorship Fund, thanks the corporate sponsors of the dinner and a few other things.
Sorry it's so dark, but this was on the still camera and I didn't have a light on it. Thankfully, as always, he was wearing his "I really am a rocket scientist" lab coat so we can at least see him as some ghostly apparation.
A bit later on in the evening, he called for a toast to the memory of Eric Dybsand. I didn't know it was coming and I had very little space left for video so I didn't tape it. I sure wish I had. We all miss you bud.
Damian Isla of Bungie has uploaded his slides from his GDC presentation (which I haven't written up my commentary on yet). He also discusses the history of the "Objectives" system that they used in Halo 3 on this blog post at Game/AI.
I will be breaking down his presentation in a few days (I'm still trying to get caught up).
I have kinda entered a vortex of browsing through other people's GDC coverage - especially on the sessions that I could not attend. Note that I don't necessarily agree with everything that people have posted here - I'm just including them so people can have a broader picture. Here's a partial list of (loosely) AI-related stuff that I have found so far:
The paradigm shift rate is now doubling every decade, so the 21st century will see 20,000 years of progress at today’s rate. Computation, communication, biological technologies (for example, DNA sequencing), brain scanning, knowledge of the human brain, and human knowledge in general are all accelerating at an even faster pace, generally doubting price-performance, capacity, and bandwidth every year. By 2020, full-immersion virtual reality will be a vast playground of compelling environments and experiences. Initially VR will have benefits in terms of enabling communications with others in engaging ways over long distances and featuring a great variety of environments from which to choose. By the late 2020s virtual environments will be indistinguishable from real reality and will involve all of the senses, as well as neurological correlation of emotions. As we enter the 2030s there won’t be a clear distinction between human and machine, between real and virtual reality, or between work and play. Intelligent nanorobots will be deeply integrated in the environment, our bodies and our brains, providing full-immersion virtual reality incorporating all of the senses, experiences "beaming," and enhanced human intelligence.
The session, while inspiring and informational, seemed to be one that he has given numerous times before - and managed to insert a few token comments here or there that loosely linked it to the game industry. That was rather distracting at times.
His main theme, as usual, was the expansion of no only the processing power (a la Moore's Law) but the "processing power" of the human mind and society as a whole. From a mathematical standpoint, I loved his use of logarithmic graphs and even double logarithmic graphs to show what amounts to constant rates of change as straight lines. He applied this to so many different things, e.g. the growth of life and intelligence, the power of supercomputing, the power over cost of computing, etc.
The crux of this issue is that people have a tendency to think linearly rather than exponentially and especially logarithmically. That means that we tend to mis-project future trends. One way that this hurts us in the technology arena is that, given production times that are getting to 3 or 4 years (Duke Nukem Forever is an outlier), we tend to undershoot the capabilities of the systems that are available by the time that we release our products.
The endpoint, of course, is his much publicized "countdown to singularity" wherein our computing power will match our mental capabilities. A couple of key predictions in this arena (which are kinda creepy in a way):
2010: Computers disappear
Images written directly to our retinas
Ubiquitous high bandwidth connection to the Internet at all times
Electronics so tiny it's embedded in the environment, our clothing, our eyeglasses
Full immersion visual-auditory virtual reality
Augmented real reality
Interaction with virtual personalities as a primary interface
(A great quote: "Real reality will continue to be irksome for a few years.")
2029: An intimate merger $1,000 of computation = 1,000 times the human brain
Reverse engineering of the human brain completed
Computers pass the Turing test
Nonbiological intelligence combines
the subtlety and pattern recognition strength of human intelligence, with the speed, memory, and knowledge sharing of machine intelligence
Nonbiological will continue to grow exponentially whereas biological intelligence is effectively fixed
One entire section of his talk was dedicated to the advances and future of nanobiology. While this seemed to be a lull in the relevancy to the game industry, there was a connection there. He actually said that, due to nanotechnology and nanobiology, we would eventually be able to reprogram our bodies the way we reprogram our games. After spending Monday and Tuesday at the Serious Games Summit where the theme was taking game and game programming technology beyond the entertainment world, I couldn't help but think that some of the techniques, especially those related to AI, would map over into some of the genetic and biological applications that he was talking about. Interestingly, this is somewhat related to things I have been reading in the book "A Beautiful Math: John Nash, Game Theory, and the Modern Quest for a Code of Nature".
One of the main interests for me and the people that I attended with was that he was often speaking largely to the AI programmers. One of his comments was that "AI is the next frontier in passing the "uncanny valley" such as it is in games. While hardly a news flash to the game world, I hope that made our stock as AI designers and programmers go up somewhat.
All in all, it was an inspiring speech if not directly relevant to today's game world... but there I go thinking linearly again. I can tell you, however, that his keynote kept coming up in roundtables, conversations, and at the AI Programmers dinner that week - every time a technique of handling prohibitively large numbers of calculations came up, his name was invoked as giving us hope that we could soon be able to handle it.
For more on Kurzweil and all of the above, check out the web site KurzeilAI.net. You can also get his slides from the keynote (9 MB .ppt file) which is where the above shots and images come from.
One of the more intruiging lectures of the 2008 GDC was given by Soren Johnson (MobyGames info) ex- of Firaxis and now with Maxis on the "Spore" team. He was talking about how Civ 4 fit in the spectrum of game AI between two extremes... "Good AI" and "Fun AI". Here's some selections from my notes on the lecture. (Forgive the seeming lack of lucidity - I was typing like a madman!)
Also, this is a direct link to Soren's Slides (.zip) on his blog - which is where the images in this post came from (click to enlarge).
“Good†AI (Play to win) Beat player at their own game Essentially a human substitute
“Fun†AI (Play to lose) Algorithms are the content Focus on the Player’s Experience
For example, Aggro in an MMO is fun AI.
With tanks, healers, DPS (damage per second) there is a formula for handling it... Trivial AI problem to “solve†by the players. Aggro determines who AI attacks, let enemy attack the tank, you heal the tank… DPS the mob… Everyone knows how it works… very predictable. Almost become commoditized with agro tools. Blizzard isn’t trying to be clever – they like that it is simple.
The question with AI design is, where are you trying to fit? Across the spectrum.
Chess is “goodâ€
Starcraft is more towards “good†(no real diplomacy – assumption is that they want to kill you.)
Civ IV split the gap. Deep diplomacy but very symmetrical game design.
Heroes of Might and Magic is more towards “funâ€. Not as focused on the excellence.
Desktop tower defense if pure "fun" AI.
Rule sets? Good side tends towards fixed rule sets. (e.g. Chess) Fun side tends towards evolving rule sets.
What are the best environments? Good AI tends towards Multi-player Fun AI tends towards Single-player
Tactics available to AI? Good AI will do everything available. Fun AI will do limited tactics.
Measuring performance? Good AI has objective measurements Fun is subjective – e.g. difficulty over performance
Turing test? Good AI passes Fun AI... this question is irrelevant.
The question is: “Play to win or Play to lose?â€
With Civ IV, the AI does have limited options. There are a lot of options that they do not put on the table for the AI. Esp. with diplomacy. E.g. fighting a war... as a player, you can ask them for stuff if you promsie to quit war, then attack them over again. AI doesn’t do that.
Civ has:
Both fixed and evolving design
Symmetrical
Single Player
Limited Options
Objective Testing
Fails Turing test but it isn’t irrelevant.
Every player is different… some want things like challenge, sandbox, narrative.
For narrative, you want to aim for personality, for the AIs to maintain memory about you. It's OK for them to fall for traps. They built that into the leaders in Civ 4.
With regard to the challenge, you "want player to win or at least understand WHY they lost."
Need for difficulty levels: Lets sandbox players off easy Gives Challenge players a goal Increases available tactics.
Where does cheating fit? Completely Good AI does not. Completely Fun AI n/a There is no concept of cheating (e.g. desktop tower defense) In the middle… yes?
The Noble level in Civ 4 is the “even level†with regard to production modifiers, etc.
But Noble has other cheats… e.g.
Animal/Barbarian combat bonuses
No Unit support
Better Unit upgrades
No Inflation
No War Weariness
The AI needs more help in these areas.
For example, AI does not leave cities empty like a human would… so unit support costs. Human army and AI army will never be the same size because they have to keep units in their cities… therefore cut the support costs for the AI since they need to have a larger army.
Cheats should NOT be linear… certain you want to help more or less as you progress your diff. levels.
Cheats should never feel unfair! Examples from past Civs that players hated...
Civ 1, 2 Free wonders Gang up on human (In Civ 1: If year > 1900 and human in lead, declare war on human)
Civ 3, 4 Human-blind diplomacy (Never checks “is human?â€) Information cheats (they DO have info cheats – most of them come down to limited dev. Resources… e.g. fog of war is very expensive)
Information cheats can really backfire on you. E.g. Amphibious Assault Judo using empty port cities in Civ 3. (solved by determining random time for updating the assault target, ignore temporary data such as nearby units.)
Cheating is relative: The Tech Trading Problem…
AI must trade techs
AI must trade fairly
Human can sell techs cheaply
Only two of these can be true… So… should AI sell techs cheaply? Solution? Can AI pursue altruism?
When the AIs were trading often, it made for very even technology levels between all players rather than some groups ahead and others lagging. Everyone had everything.
Solution in Civ IV
AI can undersell by 33% but… Tries to make up difference in gold Only trades on random turn intervals Uses same “Refuses Trade With†logic as with human.
Arbitrary rules e.g. “I will never trade Iron Working with you.â€
What is the point of cheating? Are we trying to…
Write the “best†AI?
Beat the human?
Be fair?
Designing for the AI? Can AI handle the options in the gameplay? OTOH, make sure not designing just for AI. Legitimate reason for design decision. (e.g. closed borders, enforceable peace treaties)
Traditional testing fails Automated testing helps greatly Need hard-core fans to analyze 1.5 year closed beta, peaked at 100 users, bi-weekly patches.
They used soft-coded AI: No AI scripts No enums (No “Templeâ€) Less brittle code Less predictable AI is not always a good thing.
Probabilistic Reasoning - Weights to factors, values to situation
Data-driven Mods - AI was stand-alone so that it was compiled into dll. CvGameCoreDLL.dll was 100% independent of engine.
I'm in the process of uploading all my GDC-related things to this page. You can actually listen to my audio of the 3 AI roundtables and read my (barely comprehensible) notes that I furiously took during each. Also, it has links to the pictures that I took during the roundtables and the AI Programmers Dinner on Friday night.
On that page, I will also be posting other AI-related tidbits such as my notes from lectures such as those by Soren Johnson's (Civ 4), Damian Isla (Halo 3), and Peter Molyneux (Fable 2). Give me a few days to get it all straightened out, though.
Also, I sat down with John Abercrombie of 2k-Boston on Sunday morning and spoke with him about the AI that he did for Bioshock. That should be posted on Wednesday. Look for it over on Post-Play'em.
(Remember to tap the RSS feed to keep up with these additions and all other AI-related things.)
One final note about GDC... it's always an exhilarating week... but it sure does make my head hurt!
Soren Johnson, AI guru behind Civ 3 and Civ 4, posted an interesting tidbit on his "Designer Notes" blog entitled "A Farewell to Civ". He mentioned that since he is no longer with Firaxis (having moved over to the Spore team), his GDC lecture next week will really be his last hurrah in speaking about his work with the Civ series.
One thing's for sure, I will be avoiding writing about Civ 4 in Post-Play'em until after I attend this lecture. One quote caught my eye:
Essentially, I will be talking about the difference between thinking of the AI as the player’s opponent and thinking of it as simply an extension of the core game design (what one might call the difference between “good†AI and “fun†AI). There will also be a long section on AI cheating - the bane of my existence for many years - concerning which type of cheats are acceptable to players and which type are not, using Civ as an extensive case study. Further, I hope to prove that, for Civ at least, there is no such thing as - and never could be - a “fair†difficulty level where the AI is playing the same game as the human. Your mileage , of course, might vary.
I don't want to make the mistake of assuming something he did was cheating, or something I thought was cheating was actually brilliant AI work on his part!
Cheating or not, he has done some exceptional work in making Civ 3 and Civ 4 an absolute delight to play... even as an AI guy. I'm looking forward to meeting him.
Look for updates from GDC both here and in the IA News blog.
According to this press release, Kynogon claims they are going to have "Kynapse 5" ready to roll to show at GDC next week.
I've been skeptical of AI middleware for a while, but I believe that the industry has matured somewhat to be able to pull off a lot of things in a standardized fashion. I'm definately going to have to stop by and see what they have going on.
This is my tentative schedule for GDC. I'm kind of annoyed that many of my sessions overlap. I suppose that's one of the main reasons why I bring Laurie so she can go to the business and legal ones. However, I hate having to choose between the ones on AI and agile development, for example. Heck... I haven't even checked on the keynotes like the one from Ray Kurzweil. Usually those don't conflict with other things too much, though.
Obviously, you can click on the links to learn more about the sessions and/or the people.
My week will also include:
Tuesday night:IGDA party Wednesday night: Booth crawl & Game Developers Choice Awards Thursday night: Author's party for my publisher (see sidebar for link to AI Wisdom 4) Friday night: AI Programmers Dinner and possibly Video Games Live
Take a glance at my preview on Gamasutra of the 12 sessions of the GDC AI Summit. It goes in-depth about what each session entails.
In other GDC news, After the Summit, much of the week was anti-climactic. There were the 3 normal AI roundtables as well as one run by Alexander Nareyek. I will be posting pictures and audio from the roundtables on 
One takeaway from that observation is that we will be talking about a lot of really nifty AI stuff. That much is obvious. Another takeaway, however, is that none of us... even the alleged "experts"... knows everything there is to know about AI. We all want to experience, learn, and expand. That desire comes from the somewhat discomforting awareness that there is a vast expanse of potential laid out before us. As the saying goes, "
