BioShock Infinite's Elizabeth Uses Theater Technique for AI

BioShock Infinite's Elizabeth Uses Theater Technique for AI

Irrational Games Lead Programmer John Abercrombie shed some light on the AI that made Elizabeth more than just Booker's portable ammo dispenser.

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I like the analogy! It's a play where the player gets to be an actor, yet still remains center stage. That sounds like a balancing act when it comes to a supporting cast like Elizabeth, especially with gameplay. That's not to say Elizabeth didn't have her share of problems (bogarting munitions after a battle ended comes to mind) but she was really dynamic and definitely enhanced the player's engagement.

Extremely interesting. Nice to know that some devs still care about AI. Elizabeth did show a lot of work had gone into her AI...
Problem is, other NPCs apart from her were quite stupid :( . Ohh well, still not STALKER-level AI, overall, but I salute their work on Lizz at least :)

I'm not sure if it's just me, but I never throughout the game got the feeling that Elizabeth was anything other than a game object being moved around the world, and was certainly NEVER convincing to me as an "intelligent" entity.

More often than not it was pretty obvious that she was just being teleported around to whatever "interesting point" existed in the game. One second I would see her on the right side of the screen looking at a poster, only to turn left and suddenly see her standing in the distance observing something else with no way of having appeared there other than through the magic of teleportation - a fourth-wall breaking move at best. This was even more obvious when sometimes during these mystical teleporation manoeuvres you could actually SEE the character jump across your field of view from where they were to where they were going to end up - good grief!

Finally, I would like to add that I thoroughly enjoyed the game overall, but the AI of Elizabeth is constantly bandied about and I really don't get it. Never did I see any "AI" or meaningful physical presence in the world from Elizabeth other than to occasionally pop up to hand me ammunition or other trinkets, and Elizabeth's only meaningful character interactions/interactions with the player are all entirely predefined/scripted. Her presence in the world as a whole is about as ethereal as the presence of your party during combat in The Last of Us, but at least in THAT game the characters felt interesting and real and interacted with the world and player in (what at least felt like) more meaningful ways.

yeah, that's totally not offputting at all, guys

maybe if booker had called out on her doing that, it might have worked as a joke, though

this all sounds like a contrived series of actions designed to escape that ol "link's fairy" syndrome

Tharaxis:
I'm not sure if it's just me, but I never throughout the game got the feeling that Elizabeth was anything other than a game object being moved around the world, and was certainly NEVER convincing to me as an "intelligent" entity.

More often than not it was pretty obvious that she was just being teleported around to whatever "interesting point" existed in the game. One second I would see her on the right side of the screen looking at a poster, only to turn left and suddenly see her standing in the distance observing something else with no way of having appeared there other than through the magic of teleportation - a fourth-wall breaking move at best. This was even more obvious when sometimes during these mystical teleporation manoeuvres you could actually SEE the character jump across your field of view from where they were to where they were going to end up - good grief!

Finally, I would like to add that I thoroughly enjoyed the game overall, but the AI of Elizabeth is constantly bandied about and I really don't get it. Never did I see any "AI" or meaningful physical presence in the world from Elizabeth other than to occasionally pop up to hand me ammunition or other trinkets, and Elizabeth's only meaningful character interactions/interactions with the player are all entirely predefined/scripted. Her presence in the world as a whole is about as ethereal as the presence of your party during combat in The Last of Us, but at least in THAT game the characters felt interesting and real and interacted with the world and player in (what at least felt like) more meaningful ways.

You can't really hand-waive Elizabeth's AI for not being impressive, because the reality is that majority of other "intelligent" or, at least, adjusting NPC's in games are literally bags of bricks. Other games manage to do character exploration through either: A) cutscenes, B) scripted events that often impede progress until finished or C) off-time "hub"-like dialogue. Of course they employed some tricks to make her appear places without player vision, because they don't really expect people to go out looking for it :P. It's preeeetty different compared to most other games, which sacrifice the "in-the-now" character interaction for a functional experience.
And what we define as meaningful in the case of her presence differs. Her looking at everything and making commentary -was- important, because it made it look feasible since this girl's been literally cooped up in a tower. Scripted events are scripted events, because at the end of the day Bioshock is a series which is linear in its storytelling, which is what it set out to do.
Obviously it isn't perfect x)

OT:
I think I remember hearing about something similar to this back when the game was just coming out, although this is a bit more focused on how her behavior was conceived. I do like the idea that her AI attempts to be within eyesight to actually draw some attention instead of just permanently treading behind the player and going "BOOOKKKERRRR"
"BOOKER!"
(COULSOONNNNN)

Tharaxis:
More often than not it was pretty obvious that she was just being teleported around to whatever "interesting point" existed in the game.

No idea what's wrong with your game. I only ever noticed it sometimes during combat when it came to item tossing. And I'm playing on three monitors so I really should have noticed it if it were that bad.

NoAccountNeeded:
No idea what's wrong with your game. I only ever noticed it sometimes during combat when it came to item tossing. And I'm playing on three monitors so I really should have noticed it if it were that bad.

That's likely the reason. Elizabeth is (quite correctly) teleported/transported to locations of interest only when she is outside of your field of view (otherwise it would appear very obvious that she doesn't really "exist" as a physical being in the world). Since with 3 monitors you are likely to have a far greater FOV and therefore a far greater time in which Elizabeth is not out of sight, those issues become far less noticable.

It's worth pointing out that she never teleports around when you have her in your field of view. The game only takes the opportunity to move her around when it feels you can't see what she's up to, but sometimes that behavior is very obvious when her movement between points seems largely impossible given intervening time and space.

I found this to be the worst in the "sky arcade" area.

Ferisar:
You can't really hand-waive Elizabeth's AI for not being impressive, because the reality is that majority of other "intelligent" or, at least, adjusting NPC's in games are literally bags of bricks. Other games manage to do character exploration through either: A) cutscenes, B) scripted events that often impede progress until finished or C) off-time "hub"-like dialogue.

Except Half Life 2 did helpful/believable character AI with Alyx Vance 10 years ago, who, instead of being this empty thing that gets moved around actually has a physical presence in the world, actively helps with engagements, and above all provides more meaningful interaction with the player. I'm not going to debate the pros and cons of the pacing of the game as a whole, which does have problems, but having yet again played the game recently I remain impressed with the Alyx character.

I find it hard to swallow the idea that something that was done 10 years ago cannot be done today because of "technical difficulties", and I find it funny that something that was no doubt far more technically simple compared to Elizabeth produced BETTER and more convincing results - I suspect the team not only subscribed to over-engineering/thinking the problem that Elizabeth posed thereby compromising in essentially every conceivable way, but also perhaps ended up convincing themselves that what they were doing was in some form "revolutionary". Let me iterate again - This was done BETTER and more convincingly 10 years ago.

I haven't yet seen Elizabeths AI perform tasks that couldn't be done by scripting and I have beaten the game 3 or so times now. But at least the tech behind it is interesting, maybe a better developer can actually do something awesome with it.

As a novice programmer, dealing with getting AI to go where they should has been a pretty big problem for me. But I prefer randomly-generated terrain, so very few of these ideas would work for me. But I do think it's cool how they're using a sort of synthesis between scripted events and player choice.

 

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