All language subtitles for 4. Decision Systems

Before we can discuss decision systems, we must first look at what makes an AI work.
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What are its parts?
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An AI Agent is possible because of the following parts: the brain which is responsible for the decision
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making.
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The senses or sensors are the AI's way of detecting enemies, obstacles and more.
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They are linked to the brain to provide the accurate information in real time.
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The body receives the actions from the brain and executes them, and the legs are mostly used to move
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the character using different pathfinding algorithms.
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Let's now focus on the brain of the AI, the decision systems. And there are a couple of them.
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We will take each one and discuss it a little.
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Finite State Machines.
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This AI is used a lot.
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Actions are mapped to states and the AI can be in a particular state at the specific time.
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The states are interconnected together with transitions that get triggered when a particular change
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happens to the agent.
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Specific games to this are Doom and Quake, but there are a lot of other games using finite state machines
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Behavior trees
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Are very common in most game engines, having even a direct integration in Unreal Engine.
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Their main selling point is that the designer can create any AI system without having to interact with
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any piece of code.
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They are very flexible to use.
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One example for behavior trees is of course Halo.
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Planning. This one is very similar to state machines.
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The main difference is that the states that represent the actions are not connected to each other,
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but rather these are connected real time through a specific algorithm that gets the best possible action
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sequence.
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This is not a common way to do AI, but it's found in games like F.E.A.R. Utility AI
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The utility AI does not have a particular structure but rather a set of rules.
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It's mostly used to handle complex actions like an RPG character that has multiple skills and needs
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to pick one or another based on the current situation.
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This is mostly found in RPG games or card games or games that require the AI to decide from a big list
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of actions.
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Games for this are Dragon Age Inquisition.