public Vector2D Evaluate(double u)
{
Vector2D zero = Vector2D.Zero;
List <double> doubleList = new List <double>((IEnumerable <double>) this.linkedList_0);
int knotSpanIndex = NurbsUtilD.GetKnotSpanIndex(u, (IList <double>)doubleList, this.int_0);
double[] result = new double[this.int_0 + 1];
NurbsUtilD.EvaluateBasisFunctions(knotSpanIndex, u, this.int_0, (IList <double>)doubleList, result);
List <Point2D> point2DList = new List <Point2D>((IEnumerable <Point2D>) this.linkedList_1);
int index1 = knotSpanIndex - this.int_0;
for (int index2 = 0; index2 <= this.int_0; ++index2)
{
double num = result[index2];
Point2D point2D = point2DList[index1];
zero.X += num * point2D.X;
zero.Y += num * point2D.Y;
++index1;
}
return(zero);
}
public static void EvaluateRationalBasisFunctions(
int knotIndex,
double u,
int degree,
double[] knots,
double[] weights,
double[] result)
{
NurbsUtilD.EvaluateBasisFunctions(knotIndex, u, degree, (IList <double>)knots, result);
double num1 = 0.0;
int num2 = knotIndex - degree;
for (int index = 0; index < result.Length; ++index)
{
result[index] *= weights[(num2 + index) % weights.Length];
num1 += result[index];
}
double num3 = 1.0 / num1;
for (int index = 0; index < result.Length; ++index)
{
result[index] *= num3;
}
}