UWorld::ComponentSweepMultiByChannel

function Engine Since 4.0

#include "Engine/World.h"

Access: public Specifiers: const

Description

Sweeps a component's actual collision geometry from Start to End on a specified collision channel and returns all hit results. Combines the shape fidelity of ComponentSweepMulti with explicit channel-based filtering.

Caveats & Gotchas

• PrimComp's world transform is entirely ignored — Start, End, and Rot define the pose used for the sweep.
• TraceChannel overrides the component's own collision channel for this query only — the component's response table still determines what counts as a block vs overlap.
• A convenience FRotator overload exists but internally converts to FQuat; prefer the FQuat signature for performance.
• PrimComp must have valid collision geometry and collision enabled. Components with no collision body will produce no hits.

Signature

bool ComponentSweepMultiByChannel(TArray<struct FHitResult>& OutHits, class UPrimitiveComponent* PrimComp, const FVector& Start, const FVector& End, const FQuat& Rot, ECollisionChannel TraceChannel, const FComponentQueryParams& Params) const

Parameters

Name	Type	Description	Default
OutHits	TArray<struct FHitResult>&	Array populated with all hits found during the sweep.	—
PrimComp	class UPrimitiveComponent*	Component whose collision geometry is used for the sweep. Its world transform is ignored.	—
Start	const FVector&	World-space start location of the component geometry.	—
End	const FVector&	World-space end location of the component geometry.	—
Rot	const FQuat&	Rotation applied to the component geometry for the duration of the sweep.	—
TraceChannel	ECollisionChannel	The collision channel to use for this query, overriding the component's own channel.	—
Params	const FComponentQueryParams&	Additional query parameters such as actors or components to ignore.	—

Return Type

bool

Example

Sweep a box component on ECC_Visibility to check line-of-sight blockage C++

UBoxComponent* Box = FindComponentByClass<UBoxComponent>();
TArray<FHitResult> Hits;
FComponentQueryParams Params;
Params.AddIgnoredActor(this);

bool bBlocked = GetWorld()->ComponentSweepMultiByChannel(
    Hits,
    Box,
    EyeLocation,
    TargetLocation,
    FQuat::Identity,
    ECC_Visibility,
    Params
);

if (bBlocked)
{
    // first blocking hit is Hits.Last()
    UE_LOG(LogTemp, Log, TEXT("Blocked by: %s"), *Hits.Last().GetActor()->GetName());
}

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

Feedback

Was this helpful?