/// <summary>
/// Initializes a new instance of <see cref="NurbsCurve" /> by it's control points and degree.
/// </summary>
/// <param name="controlPoints">The control points to create the curve with.</param>
/// <param name="degree">The desired degree of the curve. Degree cannot be > (ControlPoints - 1)</param>
public NurbsCurve(List <Point4d> controlPoints, int degree)
{
this.ControlPoints = controlPoints;
this.Knots = NurbsCalculator.CreateUniformKnotVector(controlPoints.Count, degree)
.ToList();
this.Degree = degree;
}
/// <summary>
/// Computes the specific amount of derivatives on the specified parameter.
/// </summary>
/// <param name="t">Parameter to compute derivatives at.</param>
/// <param name="count">Number of derivatives to compute.</param>
/// <returns>Array containing the </returns>
private IList <Vector3d> DerivativesAt(double t, int count) =>
NurbsCalculator.NurbsCurveDerivs(
this.N,
this.Degree,
this.Knots,
this.ControlPoints,
t,
count
);
/// <inheritdoc />
public Point3d PointAt(double u, double v) => NurbsCalculator.SurfacePoint(
this.ControlPoints.N - 1,
this.DegreeU,
this.KnotsU,
this.ControlPoints.M - 1,
this.DegreeV,
this.KnotsV,
this.ControlPoints,
u,
v);
/// <summary>
/// Computes the derivatives at at S(u,v).
/// </summary>
/// <param name="u">U parameter to compute at.</param>
/// <param name="v">V parameter to compute at.</param>
/// <param name="count">Number of derivatives to compute.</param>
/// <returns>Computed derivatives.</returns>
public Matrix <Vector3d> DerivativesAt(double u, double v, int count) =>
NurbsCalculator.NurbsSurfaceDerivs(
this.ControlPoints.M - 1,
this.DegreeU,
this.KnotsU,
this.ControlPoints.M - 1,
this.DegreeV,
this.KnotsV,
this.ControlPoints,
u,
v,
count);
/// <summary>
/// Initializes a new instance of <see cref="NurbsSurface" /> by it's control points and degrees.
/// </summary>
/// <param name="controlPoints">Grid of control points for the surface.</param>
/// <param name="degreeU">Degree of the surface in the U direction.</param>
/// <param name="degreeV">Degree of the surface in the V direction.</param>
public NurbsSurface(Matrix <Point4d> controlPoints, int degreeU, int degreeV)
{
this.ControlPoints = controlPoints;
this.DegreeU = degreeU;
this.DegreeV = degreeV;
this.KnotsU = NurbsCalculator
.CreateUniformKnotVector(this.ControlPoints.N, this.DegreeU)
.ToList();
this.KnotsV = NurbsCalculator
.CreateUniformKnotVector(this.ControlPoints.M, this.DegreeV)
.ToList();
}
/// <inheritdoc /> public override Point3d PointAt(double t) => NurbsCalculator.CurvePoint(this.N, this.Degree, this.Knots, this.ControlPoints, t);
