UKismetMathLibrary::Ease

function Engine Blueprint Since 4.0

#include "Kismet/KismetMathLibrary.h"

Access: public Specifiers: staticBlueprintPureUFUNCTION

Description

Interpolates between A and B using a named easing function, useful for animated transitions that need non-linear feel. Blueprint marks this node as InternalUseOnly — it is typically driven through a timeline or animation curve.

Caveats & Gotchas

• The node is marked BlueprintInternalUseOnly which hides it from the standard Blueprint palette; use the Timeline node or UCurveFloat for most Blueprint easing needs instead of calling this directly.
• BlendExp and Steps are only meaningful for the Ease* and Step easing func variants respectively — passing them with other EasingFunc types has no effect.

Signature

static ENGINE_API double Ease(double A, double B, double Alpha, TEnumAsByte<EEasingFunc::Type> EasingFunc, double BlendExp = 2, int32 Steps = 2);

Parameters

Name	Type	Description	Default
A	double	Start value.	—
B	double	End value.	—
Alpha	double	Interpolation factor in [0,1].	—
EasingFunc	TEnumAsByte<EEasingFunc::Type>	The easing function type (Linear, SinusoidalIn, SinusoidalOut, SinusoidalInOut, EaseIn, EaseOut, EaseInOut, ExpoIn, ExpoOut, ExpoInOut, CircularIn, CircularOut, CircularInOut, Step).	—
BlendExp	double	Exponent used by EaseIn/EaseOut/EaseInOut curves — higher values produce sharper curves.	2
Steps	int32	Number of steps for the Step easing function.	2

Return Type

double

Example

Ease-out a UI panel slide C++

float Alpha = FMath::Clamp(ElapsedTime / SlideDuration, 0.0f, 1.0f);
float PosX = UKismetMathLibrary::Ease(StartX, EndX, Alpha,
    EEasingFunc::EaseOut, 3.0);

Version History

Introduced in: 4.0

Version	Status	Notes
5.6	stable	—

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