Interpolators

public static class Interpolators
{
    public static double Linear(double In)
    {
        return In;
    }

    public static double LinearOut(double In)
    {
        return 1.0f - In;
    }

    public static double SineIn(double In)
    {
        return Math.Sin(In * (Math.PI / 2));
    }

    public static double SineCurve(double In)
    {
        return Math.Sin(In * (Math.PI));
    }

    public static double SineOut(double In)
    {
        return 1.0f - SineIn(In);
    }

    public static double SmoothStart2(double In)
    {
        return In * In;
    }

    public static double SmoothStop2(double In)
    {
        var Flip = (1f - In);
        return (Flip * Flip);
    }

    public static double SmoothStart3(double In)
    {
        return In * In * In;
    }

    public static double SmoothStop3(double In)
    {
        var Flip = (1f - In);
        return (Flip * Flip * Flip);
    }

    public static double Snap(double In)
    {
        return 1.0f;
    }

    public static Func<double, double> FlatSineCurve(double b = 4) => In =>
    Math.Sqrt(
        (1 + (b * b)) /
        (1 + (b * b) * (Math.Sin(In * Math.PI) * Math.Sin(In * Math.PI)))
    ) * Math.Sin(In * Math.PI);
}