Controls - LCK Documentation

ULCKStepper

Increment/decrement control for numerical values like FOV, distance, and smoothness.

Properties

Property	Type	Description
`bUseDecimals`	`bool`	Show decimal values in display

Events

OnStepperValueChanged

FOnStepperValueChanged

Broadcast when value changes.

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnStepperValueChanged, int8, NewValue);

Parameter	Type	Description
`NewValue`	`int8`	Direction: -1 (decrease), +1 (increase)

Methods

Method	Description
`Increment()`	Increase value by one step
`Decrement()`	Decrease value by one step
`UpdateCounterText(Value)`	Update displayed value text

Derived Classes

ULCKFOVButton

Field of view adjustment

ULCKDistanceButton

Camera distance control

ULCKSmoothnessButton

Camera smoothness adjustment

Example

ULCKStepper* FOVStepper = CreateDefaultSubobject<ULCKStepper>(TEXT("FOVStepper"));
FOVStepper->bUseDecimals = false;

FOVStepper->OnStepperValueChanged.AddDynamic(this, &AMyActor::OnFOVChanged);

void AMyActor::OnFOVChanged(int8 Direction)
{
    // Direction is -1 or +1
    CurrentFOV = FMath::Clamp(CurrentFOV + Direction * 5.0f, 60.0f, 120.0f);
    Camera->SetFieldOfView(CurrentFOV);
    FOVStepper->UpdateCounterText(CurrentFOV);
}

ULCKPad2D

2D directional pad for camera or value control with 8-way input.

Events

OnPad2DChanged

FOnPad2DChanged

Broadcast when direction changes.

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnPad2DChanged, FIntPoint, NewValue);

Parameter	Type	Description
`NewValue`	`FIntPoint`	Direction as (X, Y) where values are -1, 0, or 1

Example

ULCKPad2D* CameraPad = CreateDefaultSubobject<ULCKPad2D>(TEXT("CameraPad"));

CameraPad->OnPad2DChanged.AddDynamic(this, &AMyActor::OnPadChanged);

void AMyActor::OnPadChanged(FIntPoint Direction)
{
    // Direction.X: -1 (left), 0 (center), +1 (right)
    // Direction.Y: -1 (down), 0 (center), +1 (up)

    FVector Movement = FVector(Direction.Y, Direction.X, 0) * MoveSpeed;
    Camera->AddLocalOffset(Movement);
}

ULCKDisplay

Render target display surface with overlay effects for camera preview.

Methods

Method	Parameters	Description
`SetScreenOrientation`	`ELCKScreenOrientation`	Set landscape/portrait
`SetScreenRenderTexture`	`UTextureRenderTarget2D*`	Set source render target
`SetOverlayFactor`	`float` (0-1)	Set overlay intensity
`SetFlashFactor`	`float` (0-1)	Set flash intensity
`SetFlashColor`	`FColor`	Set flash color
`SetShowNotificationFactor`	`float` (0-1)	Set notification visibility
`SetUVOffset`	`FVector2D`	Set UV coordinates
`SetTextLabelVisibility`	`bool`	Show/hide text label
`AddTextLine`	`const FString&`	Add text line to display
`ClearTextLines`	-	Clear all text lines

Example

ULCKDisplay* Display = CreateDefaultSubobject<ULCKDisplay>(TEXT("Display"));

// Connect to scene capture
Display->SetScreenRenderTexture(SceneCapture->TextureTarget);

// Set orientation
Display->SetScreenOrientation(ELCKScreenOrientation::Landscape);

// Flash effect for photo capture
void AMyActor::OnPhotoTaken()
{
    Display->SetFlashColor(FColor::White);
    Display->SetFlashFactor(1.0f);

    // Fade out flash
    GetWorld()->GetTimerManager().SetTimer(FlashTimer, [this]() {
        float CurrentFlash = Display->GetFlashFactor();
        if (CurrentFlash > 0)
        {
            Display->SetFlashFactor(CurrentFlash - 0.1f);
        }
    }, 0.05f, true);
}

ULCKShowablesGroup

Container for managing multiple showable components together. Implements ILCKShowable.

Methods

Method	Description
`Show()`	Show all contained showables
`Hide()`	Hide all contained showables
`Add(NewShowable)`	Add a showable to the group
`SetUIActive(bIsActive)`	Batch enable/disable UI

Example

// Create group for camera settings UI
ULCKShowablesGroup* CameraSettings = NewObject<ULCKShowablesGroup>(this);
CameraSettings->Add(FOVButton);
CameraSettings->Add(DistanceButton);
CameraSettings->Add(SmoothnessButton);

// Show all when entering settings mode
void AMyActor::EnterSettingsMode()
{
    CameraSettings->Show();
}

// Hide all when exiting settings mode
void AMyActor::ExitSettingsMode()
{
    CameraSettings->Hide();
}

Use ULCKShowablesGroup to manage related UI elements together, reducing complexity in show/hide logic.

UI System Integration

ILCKUISystemable

Interface for UI system interaction coordination.

class ILCKUISystemable
{
public:
    virtual void SetCurrentOperatingButton(ILCKButtonable* InButtonable) = 0;
    virtual void PlayUIFeedback(bool InIsOnPressed, FVector NewTouchLocation) = 0;
    virtual bool IsCurrentOperatingButtonNull() = 0;
    virtual bool IsValidInteractor(UPrimitiveComponent* InInteractorComp) = 0;
    virtual bool CanBePressed(ILCKButtonable* InButtonable) = 0;
};

This interface allows UI components to coordinate with a central UI system for:

Preventing multiple simultaneous button presses
Playing haptic/audio feedback
Validating interactor components (e.g., specific hand or pointer)

Collision Setup

UI components use a specific collision profile for VR hand/pointer interaction:

// Set up collision for UI interaction
CollisionBox->SetCollisionProfileName(FLCKConstants::UICollisionProfileName);
// Default profile: "OverlapOnlyPawn"

Ensure your project has the “OverlapOnlyPawn” collision profile configured, or update FLCKConstants::UICollisionProfileName to match your project’s collision setup.

​ULCKStepper

​Properties

​Events

​Methods

​Derived Classes

ULCKFOVButton

ULCKDistanceButton

ULCKSmoothnessButton

​Example

​ULCKPad2D

​Events

​Example

​ULCKDisplay

​Methods

​Example

​ULCKShowablesGroup

​Methods

​Example

​UI System Integration

​ILCKUISystemable

​Collision Setup

ULCKStepper

Properties

Events

Methods

Derived Classes

Example

ULCKPad2D

Events

Example

ULCKDisplay

Methods

Example

ULCKShowablesGroup

Methods

Example

UI System Integration

ILCKUISystemable

Collision Setup