Interactor Component Overlap

What You'll Learn

• When to pick Overlap over Trace or Mouse
• The one extra setup step it needs
• Why safety tracing defaults ON for this component specifically

Core Concepts

UMounteaInteractorComponentOverlap detects interactables via physics overlap events (OnBeginOverlap / OnEndOverlap) on a sibling collision shape. It's the natural fit for first/third-person games where "walk into range" should be enough to start interacting.

UMounteaInteractorComponentOverlap : public UMounteaInteractorComponentBase

Setup

Add Interactor Component Overlap to your actor, then add a collision shape (e.g. Sphere Collision) as a sibling component - this defines the interaction range. On BeginPlay, the component auto-discovers every primitive component on the owner and configures its collision responses for you: sets the configured overlap channel to Overlap, everything else to Ignore. You don't need to touch collision presets by hand.

Only want specific components?

Fill in OverrideCollisionComponents with the exact component names to use as detection volume(s), instead of letting auto-discovery pick up everything on the actor.

Key Properties

Property	Type	Notes
OverrideCollisionComponents	TArray<FName>	Component tag filter for auto-setup
CollisionShapes	TArray<UPrimitiveComponent*>	Registered shapes with overlap events bound

API

Overlap->AddCollisionComponent(NewShape);      // binds overlap events, adds to CollisionShapes
Overlap->RemoveCollisionComponent(OldShape);   // unbinds, restores pre-interaction collision state
TArray<UPrimitiveComponent*> Shapes = Overlap->GetCollisionComponents();

Each add/remove has a batch (*Components) variant, and both route through Server RPCs when called from a client.

Safety Trace Defaults to ON

Overlap volumes can poke into an adjacent room - a sphere large enough to feel generous will happily overlap an interactable through a thin wall. SafetyTracingSetup.SafetyTracingMode defaults to ESTM_Location for Overlap interactors specifically (Trace and Mouse interactors already trace to detect in the first place, so they default to ESTM_None). Every detected candidate gets a secondary line trace validated before it's allowed into the focus list - see Interactor Runtime Config.

State-Change Behaviour

ProcessStateChanged() binds overlap events when transitioning into an active-detection state and unbinds them on Asleep / Suppressed / Disabled - so a suppressed Overlap interactor stops generating overlap callbacks entirely rather than merely ignoring them, avoiding wasted physics work while suppressed.

See Interactor System for the base component's two-tier focus model, and Interactable System for the target side of detection.