BPC_ActiveItemSystem — Active Item System
Parent Class: ActorComponent
Category: Inventory
Target UE Version: 5.5–5.7
Build Phase: 3 — Inventory
1. Overview
BPC_ActiveItemSystem manages the player's currently selected/active item and quick slot assignments. It reads from BPC_InventorySystem and maps up to 8 quick slots to inventory items, handling hotkey input, item switching, and active item context (usable, throwable, consumable).
2. Enums
E_QuickSlot
| Value |
Description |
Slot_1 |
Hotkey 1 |
Slot_2 |
Hotkey 2 |
Slot_3 |
Hotkey 3 |
Slot_4 |
Hotkey 4 |
Slot_5 |
Hotkey 5 |
Slot_6 |
Hotkey 6 |
Slot_7 |
Hotkey 7 |
Slot_8 |
Hotkey 8 |
3. Variables
| Variable |
Type |
Description |
QuickSlots |
TMap<E_QuickSlot, FGuid> |
Hotkey → Inventory Item ID mapping |
ActiveSlot |
E_QuickSlot |
Currently selected quick slot |
ActiveItem |
S_InventoryEntry |
Currently active item data |
bHasActiveItem |
bool |
An item is currently selected |
bCanSwitchItems |
bool |
Item switching allowed (not during anim) |
SwitchCooldown |
float |
Min time between item switches |
4. Functions
| Function |
Description |
SetQuickSlot |
Assigns an inventory item to a quick slot |
ClearQuickSlot |
Clears a quick slot assignment |
SelectSlot |
Sets the active quick slot by key press |
GetActiveItem |
Returns current S_InventoryEntry |
UseActiveItem |
Uses/consumes the active item |
CycleNextItem |
Selects the next populated quick slot |
CyclePreviousItem |
Selects the previous populated quick slot |
IsQuickSlotEmpty |
Returns true if quick slot has no item |
GetQuickSlotItem |
Returns item in a specific quick slot |
5. Event Dispatchers
| Dispatcher |
Payload |
Description |
OnActiveItemChanged |
S_InventoryEntry NewItem, E_QuickSlot Slot |
Active item switched |
OnQuickSlotAssigned |
E_QuickSlot Slot, FGuid ItemID |
Item assigned to quick slot |
OnQuickSlotCleared |
E_QuickSlot Slot |
Quick slot cleared |
OnActiveItemUsed |
S_InventoryEntry Item |
Active item consumed |
6. Dependencies & Communication
| System |
Relationship |
BPC_InventorySystem |
Reads inventory slots; source of truth for items |
BPC_EquipmentSlotSystem |
Automatically updates quick slots on equipment change |
WBP_HUDController |
Displays active item in HUD |
BPC_HealthSystem |
Consumed health items trigger healing |
7. Reuse Notes
- Quick slots are configurable per project (4-8 slots)
- Active item system is the bridge between inventory data and gameplay input
