It turns out that both of the GDC AI Summit lectures that I did with Kevin Dill are up on the GDC Vault for free now! Thanks to the folks at GDC for doing this — it’s a great honor to have my lectures selected as being among the free ones!
The links below will take you to the respective videos on the GDC Vault. If you are planning on attending the 2013 AI Summit at GDC, it will be helpful to watch these first. My lecture this year is a new structure for building utility-based systems using the mathematical concepts expressed in these prior lectures.
Overview: 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.
Utility-based AI is a widely-used approach, particularly for games with deeper or more complex behavior. While new users may find utility functions complex and intimidating, experienced users see them as a natural and comfortable way to express behavior. In a follow-up of their 2010 lecture, Kevin Dill and Dave Mark will show how simple problems can be laid out quickly and easily using common design patterns. Additionally, they will show how complex situations can make use of utility functions to express more nuanced behavior. They will then walk through real-world examples, showing how they would be expressed in a utility-based architecture.
About a month or two ago, I launched something that I did not bother to mention here. Mostly, that is because I have been fairly busy with other things. Also, I have found that most of the small announcements that I have to make, I have been doing on Twitter. However, realizing that there are people who may subscribe to this blog, or visit in the future, that may not follow me on Twitter, I figured it was worth a mention here.
Over three years ago, Steve Rabin and I formed the AI Game Programmers Guild. However, it was only a few months ago that we decided that we needed to put up a web site. Actually, to be more accurate, we decided to put out a web site over a year ago. We just never got around to it. Thankfully, our good friend Steve Woodcock decided that he was no longer going to be able to keep up his website. He also had a really nifty domain name: GameAI.com. We initiated a transfer of the domain so that I could start taking care of it. All I then set about setting up the new web site for the guild.
The guild web site, has many links to all sorts of information. We are hoping to continue to expand that over the years. In particular, links to people’s presentations at places such as GDC will be hosted on there. Also, links two papers on artificial intelligence, especially in the game industry. There is a news feed on that site as well where I will announce as we enter more information over the course of time.Â When appropriate, I will try to remember to cross-post on this blog as well.
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, BrÃ¼tal 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.
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.
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.
I will be speaking along with Kevin Dill (Rockstar-New England) at the GameX Industry Summit in Philadelphia this October 24-25th. From the GameX site:
“GameX Industry Summit is designed by industry professionals for industry professionals. It represents a deep and concerted production between the GameX production team and five IGDA chapters in New York, New Jersey, Boston, Baltimore and Philadelphia, bringing together the best and the brightest of the video game industry, right in the middle of the rapidly expanding East Coast game industry.”
Our lecture will be as follows:
The Art of Game AI: Sculpting Behavior with Data, Formulas, and Finesse
Whether designer, producer, or programmer, the term “game AI” summons visions of cold, sterile code. Programmers that deal in AI may be more specific in their definition by listing technical tools such as state machines, search or pathfinding algorithms, behavior trees, or planning architectures. While there is value in selecting the proverbial “right tool for the job,” in very few cases will simply using a chosen tool yield the behaviors that make our characters come alive. The life-magic that we breathe into our agents must come from the subtlety of the numbers, formulas, and relationships between data that we plug into those tools.
This lecture will explore the challenges that are involved in constructing realistic behaviors, the mindset that one must adopt to accurately model these behaviors, and the techniques that can be used to construct them. We will show that many of the decision techniques can often be applied to a project regardless of the underlying logical infrastructure. The attendee will leave with a broad summary of how to approach the artistry of constructing artificial behaviors â€“ and will likely have adopted the annoying habit of assigning values and formulas to everything they see around them.
I’m very much looking forward to sharing the stage with my friend and colleague – and the tech editor of my book, Behavioral Mathematics for Game AI (God help him!) It should be a fun and informative hour of material.
About a month ago, I was invited to sit down with Adam Templeton of Silicon Prairie News. He wanted to talk to me about Intrinsic Algorithm, my book, the state of game AI, and – more relevant to the purpose of their site – the Omaha Game Developers Association. We had a great chat for about an hour in the library on the campus of the University of Nebraska at Omaha. What resulted was a 20-minute video interview.
I was very pleased to have spoken to SPN about not only my work, but about the possibility of a professional game development community here in Nebraska.
My thanks to Adam for an excellent interview and a pleasant afternoon.
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.