UKismetMathLibrary::CInterpTo

function Engine Blueprint Since 4.0

#include "Kismet/KismetMathLibrary.h"

Access: public Specifiers: staticUFUNCTIONBlueprintPure

Description

Interpolates a linear color from Current toward Target each frame using exponential ease-out, producing a fast initial movement that slows as it approaches the target. Call this every tick and store the result back into the Current variable.

Caveats & Gotchas

• Unlike a fixed lerp, the result is frame-rate dependent unless you pass the actual per-frame DeltaTime — do not cache or batch-call with a fixed timestep.
• Passing InterpSpeed = 0 causes an immediate snap to Target regardless of DeltaTime.
• Interpolation happens per channel independently in linear RGB space; large hue shifts can pass through desaturated greys. Use LinearColorLerpUsingHSV for hue-aware blending.

Signature

static UE_INL_API FLinearColor CInterpTo(FLinearColor Current, FLinearColor Target, float DeltaTime, float InterpSpeed);

Parameters

Name	Type	Description	Default
Current	FLinearColor	Current color value this frame.	—
Target	FLinearColor	Target color to move toward.	—
DeltaTime	float	Time elapsed since the last call, typically from Tick's DeltaSeconds.	—
InterpSpeed	float	Rate of interpolation. Higher values snap faster. Pass 0 to jump immediately to Target.	—

Return Type

FLinearColor

Example

Smoothly tint a dynamic light each tick C++

// In AMyActor::Tick
CurrentLightColor = UKismetMathLibrary::CInterpTo(
    CurrentLightColor,
    TargetLightColor,
    DeltaTime,
    5.f
);
PointLight->SetLightColor(CurrentLightColor);

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

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