derivativeAt method

  1. @override
Vector2 derivativeAt(
  1. double t, {
  2. List<Vector2>? cachedFirstOrderDerivativePoints,
})
override

Returns the tangent vector at parameter t.

The return value is not normalized. The optional parameter cachedFirstOrderDerivativePoints allows the method to use previously calculated values for firstOrderDerivativePoints instead of repeating the calculations.

Implementation

@override
Vector2 derivativeAt(double t,
    {List<Vector2>? cachedFirstOrderDerivativePoints}) {
  final derivativePoints =
      cachedFirstOrderDerivativePoints ?? firstOrderDerivativePoints;
  final result = Vector2.zero();
  Vector2.mix(derivativePoints[0], derivativePoints[1], t, result);
  return result;
}