View Full Version : Jedi Knotes #6

02-09-2002, 11:13 AM
I hope I didn't miss anyone posting this yet. Anyway, here it is.

Jedi Knotes #6 - February 06, 2002

Hi, Iím Mike Gummelt, game programmer for Jedi Outcast. I'm responsible for navigation, group AI and Jedi AI as well as the Force powers and lightsaber combat system. Recently I was asked to give a rundown on our AI for an interview. Here is, essentially, what I said about it, with some elaboration and elucidation.

The enemy Artificial Intelligence (AI) in Jedi Outcast has been a major consideration throughout the course of the game's development. We've put a lot of work into developing robust systems for both the group AI and the "Jedi" AI. The new group AI helps Stormtroopers behave like a squad and also allows other enemies to work in groups. They take cover, talk to each other, take orders from Imperial Officers or group leaders, etc. They also react differently to the player based on his attack style, movements and the weapons and abilities he's using.

The group has an overall morale that affects many aspects of both their individual AI (aim, whether to flee, etc.) and the group behavior (whether to advance, outflank or fall back). For example, when faced with a squad of Stormtroopers, you can get a momentary advantage from taking out their leader, causing them to retreat and panic for a short while. Also, charging into them with a lightsaber is going to scare them a bit more than charging in with a stun baton. Itís a difficult process because if you make them too smart, they don't really seem like the Stormtroopers we know and love from the films. They need to have little regard for their own lives and they have to be fairly bad shots because of their "superior numbers" tactics. Because of these restrictions, it was difficult to find a balance, but in the end I think the Stormtrooper/group AI turned out very well.

The "Jedi" AI is another matter altogether. Their AI is totally new and from scratch because their tactics, abilities and motivations are completely separate from those of Stormtroopers. They need to be able to follow you in combat, stick with you as you move and attack as effectively as possible. The path finding here is difficult enough because they need to be able to jump anywhere you do and follow you anywhere. Aside from that, they need to be able to counter all of your non-saber weapons and, in saber to saber combat, they need to read your attacks and respond with counters and/or evasive action (whether it be a block, a dodge, a Force power or some form of acrobatic move). Unlike the original Jedi Knight, you will be fighting lightsaber users on a regular basis after you meet your first one (and, at one point, you even have Jedi allies fight along side you), so we had to put a lot of work making sure they could handle themselves in almost any situation.

The Jedi AI also needs to know when to attack and what kinds of attacks to use (including saber throwing and using offensive Force powers). All of this behavior is also tied into their "aggression" level, which ebbs and flows as the battle goes on, much like the lightsaber combat in the movies. So sometimes they'll be more cautious and keep their distance, sometimes even taunting you or turning off their saber, and sometimes they'll be charging at you full steam, being more nonverbally vocal, letting their rage take over and swinging their lightsaber unrelentingly. With the vast array of lightsaber attacks (around 8 for each of the three Lightsaber Combat Styles), defenses (blocks, parries, knockaways), acrobatics and special features (backstabs, flip-attacks, saber-locking, etc.), I have to say that this game has the most movie-like lightsaber battles outside of the movies themselves. The saber-locking feature, especially, adds a whole new dimension to our saber combat. In the films, you'll sometimes see two lightsaber combatants press their lightsabers toward the other, trying to gain ground... often, they'll use the opportunity to trade a line or two. The same happens in our game now, and I think it helps give it a more cinematic feeling without slowing down the pace of the game. The movie fight sequences have a rhythm, theyíre not non-stop hack and slash fests. They are choreographed to have a dynamic level of action. The "aggression" AI and saber-locking help the game to get closer to that choreographed feel. The saber-locks, themselves, donít last very long, and when they do happen, the player has just a few seconds to realize it and win or lose the struggle (there are a few different ways they can be resolved). Then there are all the little touches added to the AI that were implemented to make things like lightsaber fights more enjoyable (such as Stormtroopers not firing on two lightsaber combatants - like at the end of the first Star Wars movie). Overall, the AI in Jedi Outcast is extremely challenging. So much so, in fact, that in the early stages of testing, many people felt it was TOO challenging. One of the most difficult aspects of game development is play balancing the weapons and the AI and Jedi Outcast is no exception. Fortunately, weíve been able to find the delicate balance between challenging and fun and that balance is a major reason Jedi Outcast is so enjoyable to play.

Michael Chang Gummelt
Game Programmer
Raven Software

02-09-2002, 11:17 AM
Thats old stuff :)
The thread about It died already :)

02-09-2002, 11:20 AM
Lord Digl is correct.....that is old news.......but its nice to see people looking for news :D

02-09-2002, 01:03 PM
sorry :(

I guess that's what I get for leaving the forums for more than a day. :rolleyes:

Oh well, I'll just go sit in a corner now.

*quietly meanders off*