easeInOutBack static method

double easeInOutBack(
  1. double t
)

Back easing in/out.

Implementation

static double easeInOutBack(double t) {
  const c1 = 1.70158;
  const c2 = c1 * 1.525;
  return t < 0.5
      ? (math.pow(2.0 * t, 2) * ((c2 + 1.0) * 2.0 * t - c2)) / 2.0
      : (math.pow(2.0 * t - 2.0, 2) * ((c2 + 1.0) * (t * 2.0 - 2.0) + c2) +
                2.0) /
            2.0;
}