Weapon Interaction System

Weapon Interaction System

Interaction Framework

Create a flexible interaction system that handles weapon pickup, environmental interactions, and world navigation.

Basic Interact Setup

Enhanced Input Configuration

Set up interaction keybind:

• Input Action: IA_Interact
• Keybind: F key
• Input Mapping: Add to IMC_Default context
• Trigger: Started trigger for immediate response

Interact Trace System

Implement sphere trace for interaction detection:

// Player Interaction Trace
OnInteractPressed() {
start_location = GetActorLocation() + (ForwardVector * 100);
end_location = GetActorLocation() + (ForwardVector * 150);

SphereTraceByChannel(start_location, end_location, 80, 'Interact');

if (hit_result.IsValid()) {
hit_result.Actor.Interface_Interact(Self);
}
}

Custom Collision Channel

Create dedicated interaction collision channel:

• Project Settings > Collision: Add new trace channel “Interact”
• Default Response: Ignore
• Interactable Objects: Set to Block on Interact channel

Weapon Select Actor

Weapon Pickup System

Create actors for weapon selection and pickup:

Actor Components

• Arrow Component: Root for positioning control
• Skeletal Mesh: Display weapon appearance
• Box Collision: Interaction detection volume
• Rotating Movement: Visual appeal

Weapon Type System

• Animation Stance Enum Variable: Determines weapon type
• Instance Editable: Allow level designers to set weapon type
• Construction Script: Update skeletal mesh based on weapon type

Weapon Selection Function

// Weapon Type Selection
F_Set_Weapon_Type() {
switch(Weapon_Type) {
case Shield: SetSkeletalMesh(ShieldAsset); break;
case TwoHanded: SetSkeletalMesh(TwoHandedAsset); break;
case Rifle: SetSkeletalMesh(RifleAsset); break;
case Bow: SetSkeletalMesh(BowAsset); break;
case Stealth: SetSkeletalMesh(DaggerAsset); break;
case Unarmed: SetSkeletalMesh(BubbleWandAsset); break;
}
}

Weapon Equip Interface

Create communication between weapon pickups and player:

• Player Interface Function: Interface_Equip_Weapon
• Weapon Type Parameter: Pass selected weapon type to player
• Animation Stance Update: Change player’s current weapon stance

Teleporter System

Multi-Purpose Teleporter Actor

Create versatile teleporter for doors, ladders, and teleportation:

Core Components

• Arrow Component: Root component for positioning
• Static Mesh: Visual representation (door, ladder, teleport pad)
• Box Collision: Interaction detection
• Sphere Components: Teleport destination markers (Sphere_A, Sphere_B)

Teleportation Logic

// Smart Teleportation System
OnInteract(PlayerActor) {
player_location = PlayerActor.GetActorLocation();
distance_to_sphere_A = Distance(player_location, Sphere_A.Location);
distance_to_sphere_B = Distance(player_location, Sphere_B.Location);

if (distance_to_sphere_A > distance_to_sphere_B) {
PlayerActor.SetActorLocation(Sphere_A.Location);
} else {
PlayerActor.SetActorLocation(Sphere_B.Location);
}
}

Teleporter Variants

Create child blueprints for specific use cases:

Door Actor

• Static Mesh: Door asset
• Sphere Placement: One on each side of door
• Use Case: Room transitions, building entrances

Ladder Actor

• Static Mesh: Ladder asset
• Sphere Placement: Top and bottom of ladder
• Use Case: Vertical level transitions

Teleporter Pad

• Static Mesh: Magical/technological pad
• Sphere Placement: One nearby, one at distant location
• Use Case: Long-distance transportation

Environmental Interaction Actors

Trap System Enhancement

Expand statistic changer into comprehensive trap system:

Multi-Effect Trap

• Effects Array: Support multiple simultaneous effects
• Effect Types: Health damage, knockback, jump pad boost
• Customizable Power: Adjustable knockback strength, damage amounts

Knockback Implementation

// Knockback Trap Effect
OnTrapTrigger(PlayerActor) {
trap_location = GetActorLocation();
player_location = PlayerActor.GetActorLocation();

knockback_direction = FindLookAtRotation(trap_location, player_location);
launch_vector = knockback_direction.ForwardVector * knockback_power;

PlayerActor.Interface_Knockback(launch_vector, knockback_power);
}

Jump Pad System

Transform knockback traps into jump pads:

• Custom Direction: Override automatic direction calculation
• Launch Vector: Set specific X/Y/Z launch values
• Use Cases: Vertical boost, directional launching, traversal assistance

Interaction Polish

Visual Feedback

Enhance interaction system with clear feedback:

• Interaction Prompts: UI indicators when objects can be interacted with
• Highlight Effects: Visual emphasis on interactable objects
• Audio Feedback: Sound effects for successful interactions

Range and Precision

Fine-tune interaction detection:

• Sphere Radius: 80 units provides good interaction range without being overly generous
• Forward Offset: Start trace ahead of player to prevent wall-clipping issues
• Trace Length: 50-unit trace length for responsive but not excessive range

Object Organization

Organize interaction objects for level design efficiency:

• Child Actor System: Create variations without code duplication
• Instance Variables: Allow customization per-instance
• Template System: Standardized interaction objects for consistent behavior

The weapon interaction system provides the foundation for player progression, world navigation, and environmental puzzle-solving while maintaining clean, reusable code architecture.