lerp

 

function lerp(a, b, t) {
    return a + (b - a) * t;
}

function lerp(a, b, t) {
    return a * (1 - t) + b * t;
}

두 공식의 차이점과 장단점은 아래 링크에서 참고

https://en.wikipedia.org/wiki/Linear_interpolation
https://stackoverflow.com/questions/4353525/floating-point-linear-interpolation
https://www.quora.com/Why-does-a-lerp-function-implement-this-b*t-+-a*-1-t
https://math.stackexchange.com/questions/907327/accurate-floating-point-linear-interpolation