Creating Interactable Actors

This page provides real-world examples of how to create interactive objects using the Interactable class.

Note

Interactables should only be created on the server due to them leveraging the Gameplay Ability System (GAS) for interactions. This means that action callbacks are executed on the server.

Tip

Interactables are perfect for creating chests, NPCs, shop vendors, and any object players need to interact with in your game world. Interaction options can use Lua callbacks with the Action parameter or trigger gameplay abilities using the Gameplay Ability System (GAS) with the Ability parameter.

Interaction Option

{
    Text =  "string", -- The text to be displayed on the interaction option
    SubText = "string", -- The SubText to be displayed below the interaction option
    Input = "string", -- The path to the InputAction data asset
    Action? = function() end, -- The function to be used when no ability is specified
    Ability? = "string", -- The ability to be used when no callback Action is specified
}

---

Code Examples

Basic Interaction with Lua Callback

-- Simple interaction using a Lua function callback
local CoinPile = Interactable({
    {
        Text = 'Collect Coins',
        SubText = 'Press F to collect',
        Input = '/Game/Input/Actions/IA_Interact.IA_Interact',
        Action = function(CoinActor)
            print("Collected 25 gold coins!")
            -- Add coins to player inventory
        end,
    },
}, '/Engine/VREditor/BasicMeshes/SM_Cube_01.SM_Cube_01', Transform())

Interaction with Gameplay Ability

-- Using a gameplay ability instead of Lua callback
local HealingCrystal = Interactable({
    {
        Text = 'Absorb Energy',
        SubText = 'Press F to heal',
        Input = '/Game/Input/Actions/IA_Interact.IA_Interact',
        Ability = '/Game/Abilities/GA_Heal.GA_Heal_C', -- Triggers healing ability
    },
}, '/Engine/VREditor/BasicMeshes/SM_Cube_01.SM_Cube_01', Transform())

Treasure Chest with Multiple Options

-- Create a chest with multiple interaction options
local InteractionOptions = {
    {
        Text = 'Open Chest',
        SubText = 'Press F to loot',
        Input = '/Game/Input/Actions/IA_Interact.IA_Interact',
        Action = function(ChestActor)
            -- Give player random loot
            local lootAmount = math.random(10, 100)
            print("Found " .. lootAmount .. " gold coins!")
        end,
    },
    {
        Text = 'Examine Chest',
        SubText = 'Press E to examine',
        Input = '/Game/Input/Actions/IA_Examine.IA_Examine',
        Action = function(ChestActor)
            print("An old wooden chest with intricate carvings.")
        end,
    }
}

local ChestTransform = Transform()
ChestTransform.Translation = Vector(200, 200, 50) -- X, Y, Z
ChestTransform.Rotation = Rotator(0.0, 45.5, 0.0) -- Pitch, Yaw, Roll

local TreasureChest = Interactable(InteractionOptions, '/Engine/VREditor/BasicMeshes/SM_Cube_01.SM_Cube_01', ChestTransform)

Attach Interactable to Existing Actor

-- Make an existing actor interactable
local ExistingCube = StaticMesh(Vector(300, 0, 0), Rotator(), '/Engine/VREditor/BasicMeshes/SM_Cube_01.SM_Cube_01')

local CubeInteractable = Interactable({
    {
        Text = 'Push Cube',
        SubText = 'Press F to push',
        Input = '/Game/Input/Actions/IA_Interact.IA_Interact',
        Action = function(CubeActor)
            -- Apply physics impulse to push the cube
            local forwardVector = Vector(500, 0, 0)
            print("Cube pushed!")
        end,
    }
})

-- Attach the interactable to our existing cube
CubeInteractable:SetInteractableProp(ExistingCube)

Customising Interaction Point

-- Create an interactable with custom interaction point position
local BellTower = Interactable({
    {
        Text = 'Ring Bell',
        SubText = 'Press F to ring the bell',
        Input = '/Game/Input/Actions/IA_Interact.IA_Interact',
        Action = function(BellActor)
            Timer.CreateThread(function()
                local MeshComponent = BellActor:K2_GetComponentsByClass(UE.UStaticMeshComponent)[1]
                local InitialRotation = MeshComponent:K2_GetComponentRotation()

                -- Single loop with damping sine wave
                for i = 0, 300, 3 do
                    local time = i / 100.0
                    local damping = math.exp(-time * 0.8) -- Exponential decay
                    local SwingAngle = math.sin(time * 4) * 25 * damping
                    local NewRotation = Rotator(InitialRotation.Pitch, InitialRotation.Yaw, InitialRotation.Roll + SwingAngle)
                    MeshComponent:K2_SetRelativeRotation(NewRotation, false, nil, true) -- Works if Transform is replicated
                    Timer.Wait(0.03)
                end

                MeshComponent:K2_SetRelativeRotation(InitialRotation, false, nil, true) -- Works if Transform is replicated
            end)
        end,
    }
}, '/Engine/VREditor/BasicMeshes/SM_Cube_01.SM_Cube_01', Transform())

-- Move the interaction point to the top of the tower
BellTower:SetInteractionPointRelativeLocation(Vector(0, 0, 300))