> ## Documentation Index
> Fetch the complete documentation index at: https://docs.warpathstudios.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> The Ultimate Multiplayer Inventory (UMI) system is a complete, production-ready item management framework for Unreal Engine 5+, designed by WarPath Studios.

The **Ultimate Multiplayer Inventory (UMI)** system is a complete, production-ready item management framework for Unreal Engine 5+, designed by WarPath Studios.\
UMI provides core systems for:

* Inventory & storage
* Equipment & character loadouts
* Hotbar & quick actions
* Loot generation
* Crafting (optional integration)
* World item interaction
* Persistence & saving

UMI is built **multiplayer-first**, fully replicated, and optimized for authoritative server gameplay. Whether you're building a survival game, MMO, RPG, extraction shooter, or sandbox project, UMI provides a reliable, extensible foundation.

***

# **Design Philosophy**

* **Multiplayer First**\
  All operations follow strict server authority and validated RPCs.
* **Extensible Architecture**\
  Blueprint and C++ friendly with well-defined extension points.
* **Data-Driven**\
  Items, recipes, loot tables, and actions defined as Primary Data Assets.
* **Integration Ready**\
  Optional integrations with GAS, Enhanced Input, and Common UI.
* **Performance Focused**\
  Optimized replication, lightweight structs, async loading, and container-level networking.

***

# **Key Features (Summary)**

### **Inventory**

* Flexible slot-based storage
* Advanced stacking (durability, decay, provenance)
* Weight & encumbrance support
* Tag-based restrictions (per slot or container)
* Auto-stack, auto-sort, item splitting, overflow handling
* 8 sort types (name, rarity, quantity, category, value, etc.)

### **Equipment**

* Dynamic equipment slots
* Mesh swaps (skeletal & static)
* Body part hiding (hair, helmets, etc.)
* Rarity-based visuals
* Equipment presets (armor, jewelry, weapons, clothing)

### **Hotbar & Quick Actions**

* Quick slot system for weapons, tools, consumables
* Auto-refill memory
* Cooldowns per slot
* Weapon swapping with equipment integration

### **Item Definition System**

* Data Asset–driven items
* Display name, description, flavor text
* Icons, meshes, multiple mesh variants (male/female/default)
* Rarity tags
* Durability & decay
* Infusion/mod slots

### **Loot System**

* Weighted loot tables
* Level/rank scaling
* Quantity ranges
* Single-use or respawnable containers
* Easy integration with world actors

### **Crafting System**

*(Optional — only if Crafting plugin is installed)*

* SimpleQueue, MultiSlot, MaterialProcessing modes
* Data Asset–driven recipes
* Ingredient + tool + fuel requirements
* Optional ingredients with bonus effects
* Skill hooks for bonuses or perk effects
* Pause/resume + progress tracking

### **Interaction System**

* Raycast and proximity-based interaction
* Hold-interact with progress bar
* Tool requirements
* LOS checks, distance checks
* Animation montage support
* Foliage interaction

### **Persistence & Saving**

* Automatic save with configurable autosave
* ISaveable interface
* Bucket-based organization
* Level streaming support
* Async load
* Extendable backend (file, cloud, DB)
* **All other UM plugins work automatically with this system.**

### **Primary Action System**

* Central action dispatcher for item use
* GAS integration for abilities/effects
* Press/hold/release input modes
* Global cooldowns and validation
* Combo chains for melee

### **Player Profile**

* Central hub for all player systems\
  (Inventory, equipment, hotbar, crafting, abilities, etc.)
* Handles UI blocking
* Handles teleportation & location management

### **Multiplayer**

* Full replication for all item operations
* Server authority enforcement
* Validated RPCs
* Area-based networking for container replication
* Bandwidth-optimized deltas

***

# **System Architecture (Summary)**

### Player Character

```text theme={null}
PlayerProfileComponent  (central hub)
InventoryComponent      (item storage)
HotbarComponent         (quick access)
EquipmentComponent      (equipped items)
InteractionComponent    (interaction logic)
AbilitySystemComponent  (optional GAS integration)
```

### Crafting Stations

```text theme={null}
CraftingComponent
InventoryComponent (inputs)
InventoryComponent (outputs)
```

### World Containers

```text theme={null}
InventoryComponent
SaveableContainerComponent
```

### Data Asset Architecture

```text theme={null}
ItemDataAsset               (items)
ItemActionSet               (action behavior)
CraftingRecipeDataAsset     (recipes)
LootTable                   (loot)
```

***

# **Quick Start**

1. Enable UMI in your project
2. Add **InventoryComponent** to player character
3. Create **ItemDataAssets**
4. Add **InteractionComponent** to your PlayerController
5. Setup UI using the provided base widgets
6. Test item pickup, equipment, and inventory management

> For complete installation instructions, see **Installation & Setup**.

***

# **System Requirements**

* Unreal Engine 5.0+
* Gameplay Ability System (optional, recommended)
* Enhanced Input
* Common UI
* Multiplayer or single-player supported
* All platforms supported by UE

***

# **Performance Considerations**

* Per-frame save budget
* Delta replication for item changes
* Area-of-interest networking
* Async load operations
* Optional object pooling for world items