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Sensors

Sensors help the GOAP system understand the current game situation.
There are two main types of sensors: WorldSensor and TargetSensor.
Global vs. Local Sensors
Sensors can work in two modes: Global or Local.
Global: These sensors give information for all agents. For instance, IsDaytimeSensor checks if it's day or night for everyone.
Local: These sensors check only when the Planner runs. They give information for just one agent. For example, ClosestAppleSensor finds the nearest apple for a specific agent.
WorldSensor
WorldSensor checks the game's situation for an agent. It uses WorldKey to show each situation. The Planner uses this to pick the best action.
Examples:
IsHungrySensor checks if the agent is hungry.
HasAppleSensor checks if the agent has an apple.
Example
To create a new WorldSensor, create a new class that inherits from LocalWorldSensorBase or GlobalWorldSensorBase and implement its Sense method.
IsHungrySensor.cs
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using CrashKonijn.Goap.Behaviours;
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using CrashKonijn.Goap.Classes;
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using CrashKonijn.Goap.Classes.References;
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using CrashKonijn.Goap.Sensors;
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using Demos.Shared.Behaviours;
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​
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namespace Demos.Simple.Sensors.World
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{
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    public class IsHungrySensor : LocalWorldSensorBase
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    {
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        public override void Created()
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        {
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        }
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​
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        public override void Update()
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        {
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        }
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​
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        public override SenseValue Sense(IMonoAgent agent, IComponentReference references)
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        {
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            // References are cached by the agent.
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            var hungerBehaviour = references.GetComponent<HungerBehaviour>();
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​
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            if (hungerBehaviour == null)
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                return false;
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​
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            return hungerBehaviour.hunger > 20;
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        }
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    }
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}
TargetSensor
TargetSensor finds a position for a TargetKey. The Planner uses this to know how far actions are.
There are two kinds of Target: TransformTarget and PositionTarget.
TransformTarget: Use this when the target can move. For example, ClosestEnemySensor finds a moving enemy.
PositionTarget: Use this for a fixed spot. Like, WanderTargetSensor finds a random spot that doesn't move.
Example
To create a new TargetSensor, create a new class that inherits from LocalTargetSensorBase or GlobalTargetSensorBase and implement its Sense method.
ClosestAppleSensor.cs
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using CrashKonijn.Goap.Behaviours;
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using CrashKonijn.Goap.Classes;
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using CrashKonijn.Goap.Classes.References;
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using CrashKonijn.Goap.Interfaces;
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using CrashKonijn.Goap.Sensors;
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using Demos.Simple.Behaviours;
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using UnityEngine;
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​
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namespace Demos.Simple.Sensors.Target
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{
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    public class ClosestAppleSensor : LocalTargetSensorBase
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    {
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        private AppleCollection apples;
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​
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        public override void Created()
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        {
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            this.apples = GameObject.FindObjectOfType<AppleCollection>();
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        }
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​
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        public override void Update()
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        {
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        }
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​
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        public override ITarget Sense(IMonoAgent agent, IComponentReference references)
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        {
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            var closestApple = this.apples.Get().Closest(agent.transform.position);
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​
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            if (closestApple is null)
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                return null;
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            return new TransformTarget(closestApple.transform);
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        }
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    }
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}
WanderTargetSensor.cs
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using CrashKonijn.Goap.Behaviours;
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using CrashKonijn.Goap.Classes;
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using CrashKonijn.Goap.Classes.References;
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using CrashKonijn.Goap.Interfaces;
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using CrashKonijn.Goap.Sensors;
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using UnityEngine;
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​
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namespace Demos.Simple.Sensors.Target
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{
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    public class WanderTargetSensor : LocalTargetSensorBase
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    {
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        private static readonly Vector2 Bounds = new Vector2(15, 8);
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​
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        public override void Created()
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        {
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        }
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​
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        public override void Update()
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        {
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        }
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​
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        public override ITarget Sense(IMonoAgent agent, IComponentReference references)
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        {
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            var random = this.GetRandomPosition(agent);
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            return new PositionTarget(random);
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        }
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​
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        private Vector3 GetRandomPosition(IMonoAgent agent)
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        {
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            var random =  Random.insideUnitCircle * 5f;
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            var position = agent.transform.position + new Vector3(random.x, 0f, random.y);
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            if (position.x > -Bounds.x && position.x < Bounds.x && position.z > -Bounds.y && position.z < Bounds.y)
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                return position;
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​
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            return this.GetRandomPosition(agent);
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        }
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    }
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}
GoapSet
TargetKeys
Last modified 1mo ago