NBA 2K11's AI improvements
I’m Mike Wang, Sr. Game Designer on NBA 2K11. For those of you who missed the announce of my return, I just wanted to refresh you about what some of our goals were. I am excited to write a couple Insights for you in the coming weeks up to release of NBA October 5th. For this week’s Insight, Gameplay Producer, Jerson Sapida, and I are going to talk about some of the AI (artificial intelligence) improvements that we’ve made to NBA 2K11. I’ll be covering offense, and Jerson will cover defense.
Before we get into that, I wanted to reveal a new option that we’ve added for this year’s game that I am sure will excite you throughly. We have a huge team here and we all have a different perspective for how a basketball sim should be played/tuned, much like our ever-growing consumer base. One way we attempted to satisfy all parties was to introduce a new option called Game Style. Changing this option will significantly change the way you experience NBA 2K11. So when you get your hands on the game this October, play around with the different settings, as well as the difficulty level setting, to see what best fits your style of game and experience level. Here’s a quick rundown of what we were shooting for with the different settings:
Default: Kind of a hyper-realism. Shooting %’s will be slightly higher than real life, there will be fewer fouls, slightly more dunks, more and 1’s, etc. “Let ‘em play hoops” so to speak.
Casual: This is the setting you want if you like up and down play with lots of dunks and highlight moments. There won’t be a whole lot of stoppages and you’ll see higher scoring across the board. Arcade-style play is probably the best way to describe it.
Simulation: Real life stats. This is my game style of choice. With 12-min. quarters, you will easily see NBA averages across your stat lines. Don’t expect anything easy in the paint, you’ll have to work a lot harder and execute good basketball strategy to be successful in Sim.
Custom: If you manually modify sliders and settings on your own, the game slider will automatically change to Custom.
Now let’s talk about AI. Authenticity and Signature Style have always been strong points of 2K basketball. For NBA 2K11, we really wanted to take that to new heights both on the player level, as well as the team level. When I came back to the team last year and saw how much work the guys had done with the player tendencies, in partnership with 82games, I was really impressed. The thing I was most impressed by is how well all of the new tendencies had been integrated into the code. You can really see how each player rating and tendency is translated into how a real basketball player “thinks” out there on the floor. When I first played NBA 2K10, the difference between the superstars and the not-so-superstars immediately came through. But as I took the game to the lab, and really dissected each player and team, it really gave me an appreciation for just how much work had been done in that regard. Kobe loved his dribble pull up, Melo attacked like Melo on the perimeter as well as in the post, and J.R. Smith launched any shot from anywhere and everywhere without hesitation.
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Still, when we all got together to discuss upgrades for this year’s game, there were a lot of things that we wanted to see improve on the offensive end. Here are some of the new tendencies that we added for 2K11:
Tendency to use glass: Giving some love to Tim Duncan and Dwyane Wade
Tendency to Give an Go: Before this was somewhat random, now guys will pass and cut realistically based on their real life tendencies
Playmaker tendency: We really wanted to differentiate pass-first players from shoot-first players. Now guys like Steve Nash and Chris Paul will do a much better job creating offense for their teammates.
Touches tendency: This was a big one for me. We really wanted players who “dominate” the ball to feel like they controlled the ball on offense much more. Whereas before, the PG typically had the ball a majority of the time in the half-court… when things broke down you’d see the PG take over and shoot more often than we wanted. With the Touches tendency, we can ensure that the stars have the ball in their hands more, and as a result, take those tough shots to bail out their teams when plays break down. It also allowed us to re-work the way we initiate plays, which I’ll expand on shortly.
Tendency to attack strong: Some players like to bull their way through the defense when attacking the rim, while others shy away from the contact. That should now come through in NBA 2K11
Tendency to use the new shots: I’ll be going into more detail later on what all these new shots are in a later Insight, but for now, just know that there’s plenty of cool new “stuff” you can do with the Shot Stick. Obviously, it’s important that our AI players not only use all the new shot types, but also in the correct situations. Our AI engineers spent a lot of time working on this logic and it really shows. One of the coolest things to see when you’re playing against the AI, is have them break you down with a nice dribble move, see a hole in your defense, and attack it properly with the right finish. It really goes a long way to making you feel like you’re playing another intelligent human opponent rather than a machine that just randomly pushes buttons.
Dribble Move Tendencies: These were in last year as well but with the addition of new moves, it gave us the chance to go in and improve AI ball handler drive behaviors and their use of Isomotion. Instead of just standing around waiting for plays to develop, the AI will now make good use of the improved size up dribble moves, protect the ball properly when pressured, and respond appropriately when given too much space or an open lane. These changes make our AI-controlled ball handlers look much more intelligent and really put you on your toes when you’re playing defense.
Tendency for putback dunks/layups: Before this was more or less random, now guys like Dwight will be a problem on the offensive glass.
On top of giving the AI more tendencies, there were a lot of other improvements made to the AI engine to make it smarter in its attack. End of game logic was a big one as well. There’s nothing worse than having an epic back and forth battle with the AI only to have it make a bone-headed decision in the closing moments to seal its fate. Too many times the AI would dribble out the entire shot clock when needing a quick basket, fire up a long deuce when down by three, or rush in for a forced shot when it could’ve dribbled out the clock for a win. We spent a lot of time cleaning up those types of issues in NBA 2K11.
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Another big area of improvement is in our “Freelance” offense. If you’re familiar with 2K hoops, you know that Freelance is a complex set of behaviors that the AI runs when it’s not actively running a set play. This is also the state your teammates are in most of the time when you don’t manually call plays or run a set offense. One of the things we felt that needed improvement is what we call offensive teammate support. That is, whenever the user is actively “doing something” the AI needs to do its best to support that action. So, for example, if you break down your initial defender and drive the lane, your bigs should give you space inside, while your perimeter players look to spot up for jumpers or trail you in for a dish off or offensive board. Conversely, sometimes in previous iterations your AI teammates would clutter up the paint or run around frantically trying to “look busy.” We spent a great deal of time analyzing real team offenses this year and doing work to re-create how teams moved (or didn’t move) off the ball. The result is a much more realistic half-court offense and offensive behaviors that vary based on real-life tendencies. In other words, teams that run a lot of movement in the half-court will play much differently than the teams that like to stand around. This work also incorporated much attention to spacing. A lot of times your perimeter players on the weak side would creep into the mid-range or post area in NBA 2K10. This caused the defense to be a lot more compressed, resulting in an annoyingly packed interior. Now, everyone spaces the court much better, allowing for more realistic driving lanes and kickout opportunities. The last thing regarding Freelance is in relation to how guys moved away from the ball. Something that I’ve always wanted to see in a basketball game is to have guys cut, spot up, or space the floor in a way that really reflects the urgency (or in the case of weak side spacing, lack of urgency) of those types of moves. If a player cuts to the basket the exact same way he trots out to the perimeter to space the floor, it really takes away from the immersion of the experience for me. To that end, we added well over 200 dedicated off ball offensive movement animations to give life to our players. Everything from V-Cuts, to L-Cuts, to Slice Cuts, to Baseline Curls, to Backdoors… there’s an animation for every situation you can name. And when you couple the new animations with the vastly improved offensive movement model (which blend together seamlessly I should add), the flow of NBA Basketball never looked sweeter in the virtual world.
The transition game also went through a number of changes this year. This was a big sore spot for Rob Jones, who wrote the last Developer Insight and he worked closely with one of our AI engineers to ensure that fast breaks ran properly, as well as the secondary breaks and transition offense. Among other things, you’ll see changes like: improved pacing, players taking more intelligent lanes, running the break all the way through rather than spotting up unnecessarily, and players no longer crossing paths on their way up the court. On the other end, you’ll see better “pick up man” logic and the defensive anchor actually playing in the proper position. Additionally, there’s much better differentiation between the teams and players that like to get out and run vs. the ones that tend to slow it up. So instead of seeing all players take off in an all out sprint after every change of possession, you’ll see the effort players really getting out quick while some guys hang back and transition up court more leisurely.
Last but not least, the most significant AI-related offense change for NBA 2K11… revamped plays! Up until this year, plays in 2K basketball have been generic. There were a few team-specific ones, but for the most part, all teams would run the same stuff. For this year, we hired a 3rd party consultant to not only scout each and every NBA team (including classic teams for our Jordan Challenge), but to also implement and test the play data himself. It was a long and arduous process for him, but the work is a complete game changer. I’ll admit that even as a hardcore basketball gamer, I used to only call plays about 10-20% of the time in past games. Now, I pretty much call a play every trip down the floor. Not only do they run better, thanks to a lot of engineering work to improve the under the hood mechanics, they also serve to put each player in a spot to be effective given his skill set. As in real life, the plays are also crafted in such a way that several of the sets share the same basic initial setup. However, there will be wrinkles and branches within the plays themselves to disguise each play’s intent. This keeps the defense guessing and helps to make your offense that much tougher to pick apart. Re-architecting the play sets allowed us to have teams that run their offense through swings rather than their PG do the same as real life. So a team like Miami will initiate plays through Wade and Lebron, while a PG-centric team like Phoenix will still run everything through Nash. In addition to replicating a team’s real life play set, we also spent a lot of time replicating a team’s offensive tempo. More methodical teams like San Antonio will use the clock to their advantage, whereas a team like Golden State will run a few quick screens and fire at their first decent look. I can’t overstate just how much more authentic the play changes have made an already authentic NBA experience. It’s just one of those things you’re going to have to try out for yourself. But for me, it makes going into each game a new and dynamic experience where I have to craft a gameplan around my opponent. It’s cool that when I go up against a Boston vs. Orlando vs. LA vs. whoever else, that I actually have to not only strategize about how I’m going to execute my offense, but also how I plan to structure my defense to shut down their key players. And speaking of defense, I’m going to hand it over to Jerson to talk about how we’ve improved the other end of the floor.
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