Door open and close with timeline and trigger volume

Pattern: Door actor with BoxTrigger, DoorMesh, Timeline(Alpha 0→1 over 1s). BeginOverlap → PlayFromStart(Timeline). EndOverlap → Reverse(Timeline). Timeline Update: Lerp(ClosedRotation, OpenRotation, Alpha) → SetRelativeRotation(DoorMesh). For sliding: Lerp locations instead of rotations.

Create a Blueprint for a door that opens when the player overlaps a trigger and closes when they leave

Gate — open/close/toggle flow gate

Macro. Enter only passes through when gate is open.

Pickup and collectible system with overlap trigger

Pattern: Pickup actor with SphereCollision(overlap), StaticMesh visual. OnComponentBeginOverlap → CastTo PlayerCharacter → Success: call AddScore/AddItem interface on player → PlaySoundAtLocation → SpawnEmitterAtLocation → DestroyActor(self). Set collision to OverlapOnlyPawn for performance.

NearlyEqual float — check if two floats are approximately equal

Not_PreBool — logical NOT

Less (float) — A < B

OnComponentEndOverlap — end overlap on specific component

EventActorEndOverlap — fires when overlap ends

SetCollisionEnabled — enable, disable or set query-only collision

ECollisionEnabled values: NoCollision, QueryOnly, PhysicsOnly, QueryAndPhysics.