lerp static method

OutlinedBorder? lerp(
  1. OutlinedBorder? a,
  2. OutlinedBorder? b,
  3. double t
)
override

Linearly interpolates between two OutlinedBorders.

This first tries the forward interpolation, by calling b.lerpFrom(a, t) and then a.lerpTo(b, t). If both return null, this tries the same interpolation on the reversed timeline, by calling b.lerpTo(a, 1.0 - t) and then a.lerpFrom(b, 1.0 - t). If all of these methods return null, this returns a before t=0.5 and b after t=0.5.

The t argument represents position on the timeline, with 0.0 meaning that the interpolation has not started, returning a (or something equivalent to a), 1.0 meaning that the interpolation has finished, returning b (or something equivalent to b), and values in between meaning that the interpolation is at the relevant point on the timeline between a and b. The interpolation can be extrapolated beyond 0.0 and 1.0, so negative values and values greater than 1.0 are valid (and can easily be generated by curves such as Curves.elasticInOut).

Values for t are usually obtained from an Animation<double>, such as an AnimationController.

Implementation

static OutlinedBorder? lerp(OutlinedBorder? a, OutlinedBorder? b, double t) {
  if (identical(a, b)) {
    return a;
  }
  final ShapeBorder? result =
      b?.lerpFrom(a, t) ?? a?.lerpTo(b, t) ?? b?.lerpTo(a, 1.0 - t) ?? a?.lerpFrom(b, 1.0 - t);
  return result as OutlinedBorder? ?? (t < 0.5 ? a : b);
}