lerp method

@override RayOklab lerp(Ray other, double t)

Linearly interpolates between this color and other.

Parameter t should be 0.0-1.0 (0.0 = this color, 1.0 = other color).

Implementation

@override
RayOklab lerp(Ray other, double t) {
  if (t < 0.0 || t > 1.0) {
    throw ArgumentError.value(
        t, 't', 'Interpolation factor must be between 0.0 and 1.0');
  }

  if (t == 0.0) return this;
  if (t == 1.0) return other.toOklab();

  final otherOklab = other.toOklab();
  return RayOklab._(
    l: _l + (otherOklab._l - _l) * t,
    a: _a + (otherOklab._a - _a) * t,
    b: _b + (otherOklab._b - _b) * t,
    opacity: opacity + (otherOklab.opacity - opacity) * t,
  );
}