easeInOutQuint constant
A cubic animation curve that starts slowly, speeds up, and then ends slowly. This curve can be imagined as Curves.easeInQuint as the first half, and Curves.easeOutQuint as the second.
Compared to Curves.easeInOutQuart, this curve is slightly steeper.
Derived from Robert Penner’s easing functions.
Implementation
static const Cubic easeInOutQuint = Cubic(0.86, 0.0, 0.07, 1.0);