EaseExpoInOut method
Implementation
double EaseExpoInOut(num t, num b, num c, num d)
{
if (t == 0.0) return b.toDouble();
if (t == d) return (b + c).toDouble();
if ((t/=d/2.0) < 1.0) return (c/2.0*math.pow(2.0, 10.0*(t - 1.0)) + b);
return (c/2.0*(-math.pow(2.0, -10.0*(t - 1.0)) + 2.0) + b);
}