InteractSystem

Version: 1.0.0
Category: Gameplay Framework
Author: JiRath
License: MIT

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Overview

InteractSystem is a comprehensive user interaction orchestration plugin for Unreal Engine that provides end-to-end interaction management across web, mobile, and API touchpoints. The system handles event routing, session management, cross-plugin interaction triggering, and third-party service integration.

Core Purpose

InteractSystem serves as the central interaction hub for the modular plugin ecosystem, enabling seamless communication between players, game objects, and external services through a unified component-based architecture.

Key Capabilities

Capability	Description
Interaction Management	Component-based system for defining interactable objects and player interaction logic
Inventory System	Full-featured inventory with stacking, item attributes, and network replication
Equipment System	Item equipping, unequipping, and usage with visual feedback
Physics Interaction	Grab, push, and throw physics objects with configurable parameters
Trigger System	Chain interactions between multiple interactable objects
Toggleable Interface	On/off state management for interactive objects
Session Management	Player interaction state tracking and session persistence

Common Use Cases

1. Item Collection: Players pick up items that are added to their inventory
2. Door Interaction: Doors that can be opened/closed and trigger other events
3. Physics Puzzles: Grabbing and moving objects to solve environmental puzzles
4. Item Usage: Using equipped items on interactable objects (e.g., keys on doors)
5. Chain Reactions: Triggering multiple objects in sequence (e.g., pressure plates opening doors)

Role in Plugin Ecosystem

InteractSystem is a standalone plugin that provides core interaction functionality. It can be extended to integrate with other plugins in the ecosystem through custom implementation.

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Installation

Supported Runtime Environments

Environment	Minimum Version	Recommended Version
Unreal Engine	5.0	5.3+
Windows	10	11

Step-by-Step Setup

1. Copy Plugin Files

   Copy the InteractSystem folder to YourProject/Plugins/
   

2. Regenerate Project Files

   # Windows
   YourProject.uproject - GenerateProjectFiles.bat

3. Build the Project

   # Using Unreal Build Tool
   RunUAT.bat BuildCookRun -project=YourProject.uproject -noP4 -platform=Win64 -clientconfig=Development -serverconfig=Development

4. Enable Plugin in Editor

   • Open Project Settings → Plugins
   • Enable "InteractionSystem"
   • Restart the editor

Dependencies

Module	Version Constraint	Required
Core	>= 5.0	Yes
CoreUObject	>= 5.0	Yes
Engine	>= 5.0	Yes
InputCore	>= 5.0	Yes
DeveloperSettings	>= 5.0	Yes
NetCore	>= 5.0	Yes
GameplayTags	>= 5.0	Yes
Slate	>= 5.0	No (Editor only)
SlateCore	>= 5.0	No (Editor only)

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Configuration

Configurable Parameters

Parameter	Data Type	Default Value	Valid Range	Environment Variable	Security Notes
InteractDistance	float	500.0	10.0 - 10000.0 cm	INTERACT_DISTANCE	None
bAutoEquip	bool	true	true / false	INTERACT_AUTO_EQUIP	None
GrabWeightThreshold	float	25.0	0.1 - 1000.0 kg	INTERACT_GRAB_WEIGHT	None
PushImpulse	float	100000.0	100.0 - 1000000.0	INTERACT_PUSH_IMPULSE	None
MaxInventorySlots	int32	50	1 - 1000	INTERACT_MAX_SLOTS	None
bEnablePhysicsGrab	bool	true	true / false	INTERACT_PHYSICS_GRAB	None
TriggerDelay	float	0.0	0.0 - 60.0 seconds	INTERACT_TRIGGER_DELAY	None

Configuration File Example

[/Script/InteractionSystem.InteractableComponent]InteractDistance=500.0
bAutoEquip=true
[/Script/InteractionSystem.InventoryComponent]MaxInventorySlots=50

Security Considerations

• Network Replication: All inventory and interaction state changes are server-authoritative
• Input Validation: Item data is validated before being added to inventory
• Memory Safety: Uses Unreal's garbage collection for all UObject references

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Usage

Basic Interaction Setup

// C++ - Adding interaction to an actor
#include"Interaction/InteractableComponent.h"// In your actor class headerUPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "Interaction")
UInteractableComponent* InteractableComponent;
// In your actor constructor
InteractableComponent = CreateDefaultSubobject<UInteractableComponent>(TEXT("Interactable"));

// Blueprint - Event-driven interaction// 1. Add InteractableComponent to your actor// 2. Bind to OnInteract event// 3. Implement custom logic in the event graph

Inventory Management

// C++ - Adding items to inventoryvoidAMyActor::AddItemToInventory(UItemInformation* ItemInfo, int32 Quantity)
{
FItemData NewItem;
NewItem.ItemInformation = ItemInfo;
NewItem.Count = Quantity;
FItemHandle Handle;
if (InventoryComponent->AddToInventory(NewItem, Handle))
{
UE_LOG(LogTemp, Log, "Item added successfully");
}
}
// C++ - Checking inventory contentsvoidAMyActor::PrintInventory()
{
TArray<FInventoryContents> Items;
InventoryComponent->GetInventory(Items);
for (const FInventoryContents& Item : Items)
{
UE_LOG(LogTemp, Log, "Item: %s, Count: %d", *Item.GetItemInformation()->DisplayName.ToString(),
Item.ItemData.Get<FItemData>().Count);
}
}

Public API Reference

UInteractorComponent

Method	Signature	Description
Interact()	void Interact()	Initiates interaction with the currently hovered interactable
FinishInteract()	void FinishInteract()	Completes a continuous interaction
GetHoveredPrimitive()	UPrimitiveComponent* GetHoveredPrimitive() const	Returns the currently hovered primitive component
InteractWith()	void InteractWith(UPrimitiveComponent* Component)	Interacts with a specific component

UInteractableComponent

Method	Signature	Description
Interact()	void Interact(const AActor* Interactor, USceneComponent* Component)	Called when an interactor interacts with this component
FinishInteract()	void FinishInteract(const AActor* Interactor, USceneComponent* Component)	Called to finish a continuous interaction
IsPlayerInteractable()	bool IsPlayerInteractable() const	Checks if the object can be interacted with
GetInteractType()	EInteractType GetInteractType() const	Returns the interaction type (SingleUse/Continuous)

UInventoryComponent

Method	Signature	Description
AddToInventory()	bool AddToInventory(const FItemData& Item, FItemHandle& OutItemHandle)	Adds an item to the inventory
RemoveFromInventory()	void RemoveFromInventory(const FItemHandle& ItemHandle)	Removes an item by handle
RemoveItemFromInventory()	void RemoveItemFromInventory(const FItemData& Item)	Removes a specific item type
GetInventory()	void GetInventory(TArray<FInventoryContents>& OutInventory) const	Gets a copy of the inventory array
CanAddToInventory()	bool CanAddToInventory(const FItemData& Item) const	Checks if an item can be added
EmptyInventory()	void EmptyInventory()	Removes all items from inventory
GenerateUniqueHandle()	FItemHandle GenerateUniqueHandle()	Creates a new unique item handle

UEquipComponent

Method	Signature	Description
EquipItem()	void EquipItem(const FItemHandle& Item)	Equips the specified item
UnequipItem()	void UnequipItem()	Unequips the currently equipped item
ToggleEquippedItem()	void ToggleEquippedItem(const FItemHandle& Item)	Toggles item equipment state
UseItem()	void UseItem()	Uses the currently equipped item
GetEquippedItem()	FItemHandle GetEquippedItem() const	Returns the currently equipped item handle
HasItemEquipped()	bool HasItemEquipped() const	Checks if an item is equipped

UTriggerComponent

Method	Signature	Description
TriggerActors()	void TriggerActors(AActor* Instigator, UPrimitiveComponent* Component)	Triggers all configured interactables

UPhysicsGrabComponent

Method	Signature	Description
GrabComponent()	void GrabComponent(UStaticMeshComponent* GrabMesh, FHitResult Hit)	Grabs a physics object
ReleaseComponent()	void ReleaseComponent()	Releases the grabbed object
PushComponent()	void PushComponent(UStaticMeshComponent* GrabMesh)	Pushes a physics object
PhysicsInteract()	void PhysicsInteract()	Initiates physics-based interaction

Events and Delegates

Event	Signature	Description
OnUpdateHover	FUpdateHover	Called when the hovered primitive changes
OnInteract	FInteract	Called when an interaction occurs
OnFinishInteract	FFinishInteract	Called when an interaction finishes
OnInventoryChange	FInventoryChange	Called when inventory contents change
OnItemAdd	FItemAdd	Called when an item is added
OnItemRemove	FItemRemove	Called when an item is removed
OnUpdateEquipState	FUpdateEquipState	Called when equipment state changes
OnPushObject	FPushObject	Called when push state changes

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Troubleshooting

Common Error Codes

Code	Message	Resolution
EIS-1001	"Interaction failed: No interactable in range"	Ensure the interactable is within InteractDistance and bIsPlayerInteractable is true
EIS-1002	"Inventory full: Cannot add item"	Increase MaxInventorySlots or remove existing items
EIS-1003	"Item not found in inventory"	Verify the item handle is valid and the item exists
EIS-1004	"Physics grab failed: Object too heavy"	Reduce GrabWeightThreshold or use a lighter object
EIS-1005	"Network error: Server rejected interaction"	Check server authority and network permissions
EIS-2001	"Item data validation failed"	Ensure UItemInformation asset is valid and properly configured
EIS-2002	"Equip failed: No item equipped"	Equip an item before attempting to use it

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For agent-specific guidance, see AGENTS.md. Last updated: 2026-05-21