Unreal Engine 5 · Blueprint → C++
Lerp in Unreal Engine 5 C++
The Blueprint Lerp node maps to FMath::Lerp(A, B, Alpha) in C++, linearly interpolating from A to B by an Alpha factor.
Blueprint node & C++ equivalent
float A;
float B;
float Alpha;
float Result = FMath::Lerp(A, B, Alpha);What does the Lerp node do?
Lerp performs linear interpolation between A and B. With Alpha at 0 it returns A, at 1 it returns B, and at 0.5 it returns the midpoint. The formula is A + Alpha * (B - A), and FMath::Lerp(A, B, Alpha) evaluates it for you.
How to use it in C++
Call float Result = FMath::Lerp(A, B, Alpha);. FMath::Lerp is templated and also works on types like FVector, FRotator, and FLinearColor. Alpha is not automatically clamped, so values outside 0 to 1 will extrapolate beyond A and B.
Frequently asked questions
What is the C++ equivalent of the Lerp node in UE5?+
It is FMath::Lerp(A, B, Alpha), which returns the linear interpolation between A and B based on Alpha.
Does FMath::Lerp clamp the Alpha value?+
No. FMath::Lerp extrapolates if Alpha is outside 0 to 1; clamp Alpha first with FMath::Clamp if you need to stay within A and B.