At the Paris Shooter Symposium last year, the BULLETSTORM team made a great impression on many of the AI programmers and developers in the audience. Mieszko Zielinski showed off an event-driven behavior tree, the game's tactical reasoning system, and Jaroslaw Ciupinski discussed the animation-driven locomotion and the planning-based path following. Each of those, taken on their own, push the boundaries of what's been done before in games. BULLETSTORM as a whole does this too, with its innovative Skill-Shot design and ambitious use of physics simulations at different speeds in local spaces...
While the game was received very well critically, it sadly hasn't met similar commercial success, and Epic recently divulged that the sequel was discontinued. From that perspective, you can understand a question that came up after the Shooter Symposium 2011; one Lead AI Programmer discretely asked me whether BULLETSTORM was over-engineered and was this amazing cutting-edge technology something optional.
Here's the short version my answer: hell no! I figured this was an issue important enough to not treat it discretely, and since we've just released the standalone recordings from the Shooter Symposium 2011 too, it made even more sense to blog about this publicly :-)
Screenshot 1: Locomotion in BULLETSTORM is done by a multi-pass smoothing algorithm that starts at the navigation mesh level, and ends up with smooth looking curves. (Slide from the Paris Shooter Symposium 2011.)
The Benefits of Experience
The first thing to realize is that the innovation on BULLETSTORM's AI didn't come from nowhere... Mieszko for example worked at Crytek (among others) before as an AI Programmer, and no doubt expanded his knowledge of behavior trees and combat reasoning there. Crytek has been researching and developing its behavior selection trees for many years now, with each iteration improving upon the previous one. The same can be said for its combat reasoning system, for instance the cover system in CRYSIS 2 that MÃ¡rcio Martins demonstrated at the very same symposium. Not to mention that Mieszko either attended previous year's Game/AI Conference, or watched the proceedings online here at AiGameDev.com.
“By the time the team started on new technology, they had a huge head start.”
By the time People Can Fly started on new technology, with or without the Unreal Engine, they already had a huge head start. Not only could the team leverage its previous experiences, they also didn't have to maintain legacy systems and could easily avoid bad decisions made on previous projects. This is the ideal scenario for any developer, and emphasizes the importance of hiring experienced developers and investing in their continuing education.
Experienced developers don't go far out of their way to innovate.
Screenshot 2: Part of an event-driven behavior tree that was built for BULLETSTORM's enemies. The editor is built within the Unreal Engine. (Slide from the Paris Shooter Symposium 2011.)
A Programmer's Passion
Another reason that BULLETSTORM wasn't over-engineered, is that it was passion-driven. Each of the systems presented at the Paris Shooter Symposium was built by a programmer very passionate about solving those problems specific to their games, and pushing the limits of what they had seen done before in other games and engines. From the influence-map style of reasoning used in HITMAN 5, the useful debug visualizations in GHOST RECON: FUTURE SOLDIER, to the tactical navigation in BRINK... the pattern was the same.
“Why not let developers do what they are good at?”
Of course, there are some risks to following passion blindly and disconnecting from the rest of the team. However, when channeled within the context of the game, that energy has mostly (or only) benefits. It's that kind of passion that companies hire developers for, so why not let them do what they're good at?
Passionate developers innovate without doing any work!
Screenshot 3: The tactical query system in BULLETSTORM uses a combination of scoring and filtering to get the most easily tuned results and highest performance. (Slide from the Paris Shooter Symposium 2011.)
Recruiting by Leading
Leading the field by technical innovation also attracts talent, both up-and-coming developers and experienced veterans. The students and helpers at the Paris Game/AI Conference last year were all very keen to speak with Mieszko and Jaroslaw, and many discussions were raised among the Senior- and Lead-AI Programmers in the audience too. People Can Fly seems to be one of the few European studios not actively looking for AI Programmers; I'm sure they got many applicants!
“Most studios realize the benefits of being open about technology.”
Over the past couple years, we've seen most studios realize the benefits of being more open about their technology. In fact, the studios that keep their technology close to their chest rarely do so for technical reasons... But that's another article. If you're going to build the technology, your studio might as well leverage it outside of the game too!
Innovative developers attract other skilled and passionate developers.
Mitigating the Risks
There are of course, risks to technical innovation. Luckily most of those can be mitigated, in the same way that People Can Fly managed to pull it off with BULLETSTORM.
- Grounding — The biggest way to reduce innovation risk is to use a known starting point! Stay on top of recent games and their technology, use specialized sites to do that...
- Direction — Another problem is to avoid heading in the wrong direction, which tends to require interaction and feedback from other developers, for instance at specialized conferences.
At AiGameDev.com, it's our goal to provide all this for developers passionate about artificial intelligence, character animation and behavior in general...
Shooter Symposium 2011 Recordings
If you've reached this part of the article and are thinking to yourself you missed out on the Paris Shooter Symposium last year, then you're probably right! That said, you're in luck. We've compiled all the recorded videos and slides together, and made them into an amazing standalone product with a full day of high-quality videos split into four segments: animation & locomotion, behavior logic, combat reasoning, and design & authoring.
There are a few ways you can get your hands on it:
- You can purchase it standalone from the store for the price of 397€; it's at 20% introductory discount until May 1st.
- As per popular request, year-long PREMIUM memberships without subscription are now available, at 997€ for GOLD. You get the Symposium for free until May 1st!
- If you're currently a PLATINUM Studio member, or you've been a GOLD Studio member for over a year, then the symposium is now accessible for you at the Symposium page
Do you think it's useful to let programmers work on what they are passionate about? Does technical innovation have benefits for studios, both within the game and outside?
Post a comment below or in the forums associated with this article!