UKismetSystemLibrary::LineTraceSingleForObjects

function Engine Blueprint Since 4.0

#include "Kismet/KismetSystemLibrary.h"

Access: public Specifiers: staticBlueprintCallable

Description

Traces a line from Start to End and returns the first hit against any component whose collision is set to respond to one of the given Object Types. Exposed to Blueprint as 'Line Trace For Objects'.

Caveats & Gotchas

• ObjectTypes filters by UE's Object Type classification (WorldStatic, WorldDynamic, Pawn, Vehicle, Destructible, PhysicsBody, plus custom types), which is entirely separate from Trace Channels — a component's per-channel collision responses don't affect whether it's found here, only its 'Object Type' setting in the collision profile does.
• Because this queries by Object Type rather than channel, there's no concept of a blocking response overriding an overlap response — any component with a matching Object Type registers as a hit.
• ActorsToIgnore is still respected even though the filtering model is different from the by-channel traces.

Signature

static ENGINE_API bool LineTraceSingleForObjects(const UObject* WorldContextObject, const FVector Start, const FVector End, const TArray<TEnumAsByte<EObjectTypeQuery> > & ObjectTypes, bool bTraceComplex, const TArray<AActor*>& ActorsToIgnore, EDrawDebugTrace::Type DrawDebugType, FHitResult& OutHit, bool bIgnoreSelf, FLinearColor TraceColor = FLinearColor::Red, FLinearColor TraceHitColor = FLinearColor::Green, float DrawTime = 5.0f )

Parameters

Name	Type	Description	Default
WorldContextObject	const UObject*	World context.	—
Start	const FVector	Start of the line segment.	—
End	const FVector	End of the line segment.	—
ObjectTypes	const TArray<TEnumAsByte<EObjectTypeQuery>>&	Array of Object Types to trace against.	—
bTraceComplex	bool	True to test against complex collision, false to test against simplified collision.	—
ActorsToIgnore	const TArray<AActor*>&	Actors to exclude from the trace.	—
DrawDebugType	EDrawDebugTrace::Type	Debug draw mode.	—
OutHit	FHitResult&	Properties of the trace hit.	—
bIgnoreSelf	bool	Whether to ignore the world context actor itself.	—
TraceColor	FLinearColor	Debug draw color for the trace.	FLinearColor::Red
TraceHitColor	FLinearColor	Debug draw color for hits.	FLinearColor::Green
DrawTime	float	How long the debug draw persists, in seconds.	5.0f

Return Type

bool

Example

Line trace against dynamic world objects only C++

FHitResult Hit;
TArray<TEnumAsByte<EObjectTypeQuery>> ObjectTypes;
ObjectTypes.Add(UEngineTypes::ConvertToObjectType(ECC_WorldDynamic));

TArray<AActor*> ActorsToIgnore;
ActorsToIgnore.Add(this);

const FVector Start = GetActorLocation();
const FVector End = Start + GetActorForwardVector() * 1000.f;

bool bHit = UKismetSystemLibrary::LineTraceSingleForObjects(this, Start, End, ObjectTypes, false, ActorsToIgnore, EDrawDebugTrace::ForDuration, Hit, true);

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

Feedback

Was this helpful?