NPC Memory System

NPCs remember player actions and calculate cumulative attitude.

Overview

Player:
- Stole from merchant 3 times
- Saved a villager

NPCs:
  Merchant: "You again... keep your hands off my stuff."
  Villager: "Thanks for saving me last time."

Component

NPCMemory — MonoBehaviour. Add to the NPC GameObject.

Field	Type	Default	Description
MaxMemories	int	20	Max memory count. Oldest is deleted when exceeded.
memories	List<MemoryEvent>	—	Stored memory list (viewable in Inspector)

API

Remember

void Remember(EventType type, float weight = 1f, string context = "")

Records a player action.

Parameter	Description
type	Action type (EventType enum)
weight	Attitude impact. Positive = friendly, Negative = hostile
context	Optional description string

npc.Remember(EventType.Steal,  weight: -3f);
npc.Remember(EventType.Help,   weight:  5f);
npc.Remember(EventType.Attack, weight: -10f);
npc.Remember(EventType.Gift,   weight:  3f);

GetAttitude

float GetAttitude()

Returns the sum of all memory weights.

float attitude = npc.GetAttitude();

// attitude > 0  → friendly
// attitude == 0 → neutral
// attitude < 0  → hostile

HasMemory

bool HasMemory(EventType type)

Checks if a specific memory type exists.

if (npc.HasMemory(EventType.Steal))
    dialogue.Say("You again...");

ForgetOldest

void ForgetOldest()

Manually removes the oldest memory. Called automatically when MaxMemories is exceeded.

---

EventType Enum

public enum EventType
{
    None,
    Steal,
    Help,
    Attack,
    Trade,
    Talk,
    Threaten,
    Gift,
    Kill,
    Rescue
}

MemoryEvent Structure

public class MemoryEvent
{
    public EventType Type;
    public float Timestamp;  // Based on Time.time
    public float Weight;
    public string Context;
}

---

Example

using NpcMentality;

public class ShopKeeper : MonoBehaviour
{
    private NPCMemory _memory;

    private void Awake() => _memory = GetComponent<NPCMemory>();

    public void OnPlayerSteals()
    {
        _memory.Remember(EventType.Steal, weight: -3f, context: "rare herb");

        float attitude = _memory.GetAttitude();
        if (attitude < -6f)
        {
            GuardSystem.Alert(transform.position);
        }
    }

    public string GetGreeting()
    {
        float attitude = _memory.GetAttitude();
        return attitude switch
        {
            < -5f => "Get out.",
            < 0f  => "What do you want?",
            < 5f  => "Welcome.",
            _     => "I wish I had more customers like you!"
        };
    }
}