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Post-Play'em - Observations on Game AI

Mass Effect: First Look

I've had my copy of Mass Effect (yes, the original) from GameFly for a month or so now. My son played it for a few straight weekends when he was visiting and finally finished it. Seeing how long it took him to go through has convinced me that I do not have the time to ever complete the game. However, I did want to get a feel for what it was like specifically for reference purposes. Here's a few of my first impressions.

Good Dialog Animation
One thing I noticed that was rather pleasant was that the cut scene dialog animation was reasonably well done. This is even more impressive since there are at least a dozen races that I have encountered so far and all of them look believable when they are speaking. I happen to have a soft spot for ol' Urdnot Wrex who looks particularly compelling when he speaks. Kudos to BioWare for pulling that off well.

Fixed Cut Scenes
On a down side of that is the fact that I now feel really rooted to the ground during those dialogs. Much of this is by an unfair comparison, however. After playing Assassin's Creed where I could wander around aimlessly during dialogs, I found myself a little restrained during the Mass Effect ones (of which there are plenty). Which brings me to another point...

Odd Disconnects
Having been a veteran of Neverwinter Nights, I am well familiar with the extent that BioWare can take their contextual dialog trees. While I agree that this is still largely a necessary evil in RPG games, there are times when I am a little alarmed by a continuity disconnect.

For example, upon arriving in Noveria, I had a pleasant chat with the lady Gianna. She tells me upstairs at the security station to come see her to have an appointment with Anoleis. It took me less than a minute to get down to her office where she greeted me with the question, "What do you want?" It was rather startling to have just left her and have her forget that she told me to come ask her something specific. Of course, this is something that can be chalked up in part to poor writing. On the other hand, this is also something that could have been added as a trigger flag in the dialog tree itself. That is, if the player gets to you quickly, acknowledge it and say something appropriate. In this case, it would have been "Ah, you are here. Let me announce you to Anoleis."

On the other hand, the in-dialog flags seem to be well done. Often, they will remember that I have asked about one topic in another branch of the tree entirely. That is well done. Of course, I was tickled when one character told me off by saying we have already discussed something. On the other hand, I can see how that would be annoying if you were distracted by something and didn't hear what was said.

Another peculiar interaction was when Gianna met me outside a room after I had finished a combat sequence. (I believe it was outside that one dude's office.) She told me to talk to her in the hotel bar before I spoke to the guy who sent me on the mission. Uh... OK. The problem was, as soon as the cutscene was over, she was gone. We didn't get to see her walking away or going to the bar, etc. Not having anything else to do, I went to the bar and found her already there (she's quick!). Again, this effect is a by-product of having the cutscenes be somewhat de-coupled from the actual live action gameplay. It's mildly annoying.

Not much of that has to do with AI, however. This next bit does.

Combat AI
In a few of the combats that I have been in, I've noticed a peculiar combination of tactics. While I praise the design that puts some enemies behind cover for a while. It seems like they also leave cover for no reason, walk some pre-programmed path while still firing at me, then return to cover. If that doesn't smack of a shooting gallery, I don't know what does. Additionally, there have been times when an enemy inexplicably leaves cover and runs right up to me in the open. It seems to be a design decision to "mix things up" however. While mixing things up is fine, it doesn't really make a lot of sense from a combat standpoint. Because of that, it makes the enemy look dumb. If the enemy looks dumb, people think the AI is dumb. It is unwise to intentionally write something into your enemy AI that people will perceive as being broken - either technically or in the "brain" of the enemy.

All in all, the AI seems to alternate between overly scripted or a sequence of randomly strung together actions. There isn't that cohesive combat flow that I experience in the likes of Halo 3, Gears of War 2, or F.E.A.R. Interestingly, this makes the battles almost as mundane as the incessant walking (jogging) and driving that you have to do in the game. Where I would hope to have the proverbial minutes of terror to break up the hours of boredom, I don't even get a rise out of the combat. That's disappointing.

Anyway, while I don't plan on finishing the game, I will put a few more hours into it and see if I notice anything else.

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Assassin's Creed: First Look

In my latest episode of "finally got around to playing", I have had a chance to mess with Assassin's Creed (on X360). As with most people, I was immediately impressed by how visually attractive the game is. However, that has usually been a warning bell in the past. A lot of time "pretty game" has tended to also portend "stupid AI". This doesn't seem to be the case with AC.

While this isn't normally my strong suit, I have to say that the animation model in the game is very well done. Even without the climbing and hoping and dodging, there is a lot of detail that made for convincing depth in the characters. Even just running forward and then rapidly changing to run the other direction prompts a foot plant and skid animation that is really kind of cool. I also like the fact that the transitions between animations are very smooth. Even just something as simple as changing from a walk to run and back to a walk (even on horseback) exposes a gradient of speed that does not have the hard-edged state change feel.

Look at me when I'm talkin' to ya!

I also like how you can move around during the (long) dialog scenes. You don't have to, but you can. In fact, I found myself wanting to pace during these conversations because it made it more realistic. Additionally, when your character says something while he is facing away from the listener, he will turn slightly towards him... not to directly face him, but to talk in his general direction. Think about it... don't we all do this? How often do we actually look directly at the person we are talking to? It's a nice touch with the animation that makes those plentiful dialog exchanges more livable.

Running, Jumping, and Climbing on Things

It goes without saying that the advanced animations are very well done. The climbing and running and jumping business is ridiculously well done. There are the occasional quirks but those are more of a problem with the control scheme (on the 360) than anything else. I especially like when I get too close to an edge and my dude has to fight to keep his balance.

Excuse me. Pardon me. Move, damnit!

There are ways that they incorporated this into the game design other than all of the building stuff, however. It was a very nice touch to have the character stagger or even fall when he runs into people. That makes the chase scenes through cities very realistic in that you do have to pay a little attention to where everyone is.

Of course, in order to utilize that mechanic, you have to pack the streets full of people going about their business. This was done very well. There are places where it is next to impossible to run through simply because of the press of people. Even walking through them can get annoying. I haven't bothered to simply watch people to see where they are going, but you don't get that initial impression of "random walk" that you get from a lot of other games. (One recent transgressor in this effort was when I was playing Oblivion where every person in the city just broadcasted "I am so lost!" I will write up my observations on Oblivion later.)

An even better touch is how the people react to your passing... not just physically, but verbally. If you bump into one of those jar-toting ladies and get them to drop their burden, they will give you a little lip. The same can be said for running into a dude when you are on a horse. I found myself being more careful moving through people just to avoid what should be relatively innocuous confrontations.

The agents in the game, be they friend or foe, do have a pretty obvious state-based behavior pattern. It works for this game, however. I also haven't seen any situations where the FSM is stuck on stupid. The game mechanic has enough depth that the predictability of the guards is acceptable.

Now serving #43

I guess the only thing I can fault (although it still works well) is the "ninja fight" rules where the enemies tend to come at you one at a time. They do take turns, however, rather than waiting for the one fighting you to die before the next steps in. Again, this was matched well with the game mechanic of being able to grab people and throw them away. When you toss one dude away, his buddy will step right in. It does make the fight more manageable, however. On the other hand, there have been times when I have had more than one guy beating on me at the same time. I haven't figured out what the difference is in those scenarios, however.

All in all, the game looks pretty good from an AI standpoint. I say that based on the fact that I haven't noticed anything horrible about it. That's usually a sign that things are working well. Figure that AI should be like umpires or referees in a sports game. They are necessary for the game to work smoothly, but you shouldn't really notice that they are there.

I'm returning AC to GameFly tomorrow (although I will probably buy it because my kids are addicted to it) so it will be a bit before I follow up on this post. You can check to see if I have written anything else by clicking the Assassin's Creed tag below.

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