Goal-Oriented Action Planning: Ten Years of AI Programming

In this 2015 GDC talk, AI Programmers Chris Conway, Peter Higley and Eric Jacopin revisit the Goal-Oriented Action Planning method of game AI programming to see how it's held up for the last 10 years, and how it influenced the AI of Middle Earth: Shadow of Mordor and Tomb Radier.

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[mystic]

it's so simple but using a* to traverse a graph of actions is something i've never thought of. it's burnt into my brain that a* is for a graph of, well, places.

[olon]

Using A* to traverse a graph of actions to achieve a desired world state and find the shortest path from current world state to desired world state is brilliant. So damn clever! Please excuse me, I must start prototyping! 100/10 talk within the first 10 minutes.

[lifetheoryoptimal]

simply persuasively thinking about my own life about it in terms of A* makes me think about how sub optimal I have been, especially lately. I'm like a complex GOAP with a 10% chance of changing my goal for every node traversal

[Kinos]

GOAP is surprisingly easy to write, relatively. I used Unreal Engine 4 to write an AI that looks for a weapon, then ammo, then attacks. It was super cool.

[thomascook]

People watching this should check out LGOAP. It's a layered version of GOAP that allows to generate much longer plans without a massive computational overhead. Basically, the idea is generate a high level plan (build base -> build army -> attack). Then, for each actions world state in the high level plan, generate a mid level plan that satisfies those conditions. So, for build command center the mid level plan would be (build workers -> build barracks). Then, again, for each mid level actions world state, generate a low level plan that satisfies those conditions. So, for build workers it would be (build scv -> mine -> build scv -> mine -> build scv).

So you'd end up with a plan like so (when you concat all the low level plans together):

(build scv -> mine -> build scv -> mine -> build scv) -> (send worker to -> build barracks -> mine) -> (build marine -> build marine -> build marine -> build marine) -> (move army to -> attack on sight)

[Hayzl]

F.E.A.R. still has one of the most deadliest A.I. I can remember in a game. They will try to get you out of your position and will flank you. One of the memorable things about them is they really seemed to communicate and do their actions. Interesting to see how they achieved it.

[toketokepass]

THIS IS GOLD. Thank you so much, exactly what I was looking for.

[Fitzgibbon]

Damn, this was a cool listen. Been thinking for a while about a somewhat complex RPG system, and this is an amazing addition to the toolkit.

[mattwla]

Almost didn't watch this due to some critical comments, but glad I did. Recommended viewing if you are thinking about or are implementing GOAP!

[HumanityAsCode]

I'm seeing a lot of wannabe developers knocking systems they can't even understand in the comments. This is impressive stuff.

[JosephDungee]

I LOVE this Talk!!! I am having to stop watching this because me as a "Player" doesn't want to be aware of all the AMAZING System in the game...right now. I have to say though as a "Programmer and designer" I love what I am learning about how GOAP and The Nemesis System along with others which were implemented in Middle Earth: Shadow of Mordor

[elliejayliquid]

That system is awesome, need to find more good talks about it. The presenter is struggling a bit, but I'm still picking up new interesting things on the way.

[wacky.racoon]

Awesome, this is a freaking crash course, really nice talk !

[BungieStudios]

He's the Spider-Man of AI development. I wish more developers invested in game AI. Online multiplayer games have kind of disrupted this. I'm hoping cloud service integration and use of multiplayer mobs inspire a return to their continued advancement.

[yrussq]

Well, what Peter was talking about sounded way more logical and easy to maintain, while Chris' version sounded like an enormous all-in-one blob. I wonder about Chris' general system design of his thing - i hardly believe that it's a blob.

Anyway, very informative talk!

[netbat]

wow, I could use some of this to make something genuinely interesting. too bad I only have enough initiative and patience to make what are effectively digital dice.

[enikey]

Give this man a 1 year full paid vacation. He look so tired of all this shit.

[numgun]

It feels cathartic to see someone struggle when trying to explain an abstract complicated system to an audience of random people. I know that agony all too well.

[DeMZIrus]

Why is there 2 GDC logos in lower right?

[stephenborntrager]

11:56 Is that real-time... weapon change!?