Original subtitles

0 Before we can discuss decision systems, we must first look at what makes an AI work. 1

What are its parts? 2

An AI Agent is possible because of the following parts: the brain which is responsible for the decision 3

making. 4

The senses or sensors are the AI's way of detecting enemies, obstacles and more. 5

They are linked to the brain to provide the accurate information in real time. 6

The body receives the actions from the brain and executes them, and the legs are mostly used to move 7

the character using different pathfinding algorithms. 8

Let's now focus on the brain of the AI, the decision systems. And there are a couple of them. 9

We will take each one and discuss it a little. 10

Finite State Machines. 11

This AI is used a lot. 12

Actions are mapped to states and the AI can be in a particular state at the specific time. 13

The states are interconnected together with transitions that get triggered when a particular change 14

happens to the agent. 15

Specific games to this are Doom and Quake, but there are a lot of other games using finite state machines 16

Behavior trees 17

Are very common in most game engines, having even a direct integration in Unreal Engine. 18

Their main selling point is that the designer can create any AI system without having to interact with 19

any piece of code. 20

They are very flexible to use. 21

One example for behavior trees is of course Halo. 22

Planning. This one is very similar to state machines. 23

The main difference is that the states that represent the actions are not connected to each other, 24

but rather these are connected real time through a specific algorithm that gets the best possible action 25

sequence. 26

This is not a common way to do AI, but it's found in games like F.E.A.R. Utility AI 27

The utility AI does not have a particular structure but rather a set of rules. 28

It's mostly used to handle complex actions like an RPG character that has multiple skills and needs 29

to pick one or another based on the current situation. 30

This is mostly found in RPG games or card games or games that require the AI to decide from a big list 31

of actions. 32

Games for this are Dragon Age Inquisition.