UKismetMathLibrary::VInterpTo

function Engine Blueprint Since 4.0

#include "Kismet/KismetMathLibrary.h"

Access: public Specifiers: staticBlueprintPure

Description

Smoothly moves a vector toward a target each frame using an exponential decay approach. Produces a natural ease-out feel without overshooting. Commonly used for camera lag, smooth following, or any value that should catch up to a moving target.

Caveats & Gotchas

• The underlying formula is frame-rate dependent by design — the feel changes at different frame rates. If consistent behavior across frame rates is critical, use FMath::VInterpConstantTo or accumulate with a fixed timestep. In practice the visual difference is subtle for typical game frame rates.
• Passing InterpSpeed = 0 causes an immediate snap to Target (the function special-cases it). This is useful for initializing the value on the first frame, but be careful not to accidentally pass 0 during normal gameplay if you expect gradual movement.

Signature

static UE_INL_API FVector VInterpTo(FVector Current, FVector Target, float DeltaTime, float InterpSpeed);

Parameters

Name	Type	Description	Default
Current	FVector	The current value to interpolate from.	—
Target	FVector	The target value to interpolate toward.	—
DeltaTime	float	Time elapsed since the last call, in seconds.	—
InterpSpeed	float	Interpolation speed. Higher values converge faster. Pass 0 to snap immediately to Target.	—

Return Type

FVector

Example

Smooth camera lag in Tick C++

void AMyPlayerController::PlayerTick(float DeltaTime)
{
    Super::PlayerTick(DeltaTime);
    FVector TargetCamPos = GetPawn()->GetActorLocation() + FVector(0, 0, 200);
    CameraLocation = UKismetMathLibrary::VInterpTo(CameraLocation, TargetCamPos, DeltaTime, 5.f);
    Camera->SetWorldLocation(CameraLocation);
}

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

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