update method

@override void update(double dt)

Implementation

@override
void update(double dt) {
  var value = 0.0;
  if (dt < 0.5) {
    dt *= 2;
    value = (1 - bounceTime(1 - dt)) * 0.5;
  } else {
    value = bounceTime(dt * 2 - 1) * 0.5 + 0.5;
  }
  innerAction.update(value);
}