TableArea

Abstract MonoBehaviour that defines a trigger-based detection zone on a shop Table. Automatically tracks items entering and leaving the collider bounds by wrapping them as ShopItem instances. Subclass to define specialized table areas (e.g., DisplayArea for item display, TradingArea for trade interactions).

Definition

Namespace: Paragon.Townskeep.ShopSystem Assembly: Townskeep.dll

[RequireComponent(typeof(BoxCollider))]
public abstract class TableArea : MonoBehaviour

Inherits: MonoBehaviour

Remarks

TableArea uses Unity's trigger system to automatically detect items placed on or removed from the table surface. When a collider with an Item component enters the trigger, a ShopItem wrapper is created and added to the tracked list. When it exits, the corresponding wrapper is found and removed.

The BoxCollider (required via [RequireComponent]) should be set as a trigger and sized to match the table surface. Items must have colliders to interact with the trigger zone.

Two Transform reference fields (innerSpot and outerSpot) provide configurable positions used by AI agents for navigation — InnerSpot is where an agent stands behind the table (shopkeeper side), while OuterSpot is where a customer stands.

Known Subclasses

Subclass	Purpose
DisplayArea	Display-only area (no additional behavior)
TradingArea	Supports agent-initiated trade workflows with TradeContext

Quick Lookup

Goal	How
Get all tracked items	tableArea.Items
Add an item manually	tableArea.DisplayItem(item)
Remove an item manually	tableArea.RemoveItem(item)
Get area bounds	tableArea.GetBounds()
Get shopkeeper position	tableArea.InnerSpot
Get customer position	tableArea.OuterSpot

Properties

Items

public IEnumerable<ShopItem> Items { get; }

All ShopItem instances currently tracked in this area. Includes both reserved and unreserved items.

InnerSpot

public Transform InnerSpot { get; }

Configurable transform marking the shopkeeper-side position. Used by AI agents for pathfinding. Set via Inspector.

OuterSpot

public Transform OuterSpot { get; }

Configurable transform marking the customer-side position. Used by AI agents for pathfinding. Set via Inspector.

Fields

boxCollider (protected)

protected BoxCollider boxCollider;

The required trigger collider, set in Awake() via GetComponent<BoxCollider>().

items (protected)

[ShowInInspector, ReadOnly]
protected List<ShopItem> items;

The tracked item list. Visible in Inspector as read-only via Odin attributes.

Methods

DisplayItem

public void DisplayItem(Item item)

Creates a ShopItem wrapper for the given item and adds it to the tracked list. Called automatically by OnTriggerEnter, but can be called manually.

Parameter	Type	Description
item	Item	The item to track

RemoveItem

public void RemoveItem(Item item)

Finds the ShopItem wrapping the given item (via implicit conversion comparison) and removes it from the tracked list. Called automatically by OnTriggerExit.

Parameter	Type	Description
item	Item	The item to stop tracking

GetBounds

public Bounds GetBounds()

Returns the world-space bounds of the BoxCollider.

Returns: The boxCollider.bounds.

Extension Points

Subclassing

TableArea is abstract — subclass it to add specialized behavior:

Override/Add	Purpose
Custom methods	Add trade logic, layout logic, etc.
Access items	The protected list is directly accessible in subclasses
Access boxCollider	The protected collider is available for custom bounds logic

Implementation Requirements

When subclassing, you MUST:

1. Ensure the GameObject has a BoxCollider set as a trigger

You SHOULD:

• Assign InnerSpot and OuterSpot transforms in the Inspector for AI navigation

• Avoid overriding Awake() without calling base.Awake() — it initializes the items list and box collider

Awake() is not virtual in this class. If a subclass defines its own Awake(), Unity will call only the subclass version, and the items list and box collider will be null. Use Start() for subclass initialization instead.

Common Pitfalls

BoxCollider must be a trigger The [RequireComponent] ensures a BoxCollider exists, but it does not set isTrigger = true. The collider must be configured as a trigger in the Inspector for OnTriggerEnter/OnTriggerExit to fire.

Items need colliders OnTriggerEnter/OnTriggerExit only fire for GameObjects with colliders. Items without colliders will not be detected.

RemoveItem uses implicit conversion for matching RemoveItem() finds the matching ShopItem via items.Find(shopItem => (Item)shopItem == item), using the implicit conversion operator. This compares by Item reference identity.

Duplicate entries possible If DisplayItem() is called manually for an item that has also entered the trigger, the item will be tracked twice. There is no duplicate check.

See Also

• Table — parent component that queries items

• ShopItem — the wrapper created for each detected item

• TableNetwork — network component on the same table