Import
NURBSUtils is an addon, and must be imported explicitly, see Installation#Addons.
import * as NURBSUtils from 'three/addons/curves/NURBSUtils.js';Methods
.calcBSplineDerivatives( p : number, U : Array.<number>, P : Array.<Vector4>, u : number, nd : number ) : Array.<Vector4> (inner)
Calculates derivatives of a B-Spline. See The NURBS Book, page 93, algorithm A3.2.
| p |
The degree. |
| U |
The knot vector. |
| P |
The control points |
| u |
The parametric point. |
| nd |
The number of derivatives. |
- Returns: An array[d+1] with derivatives.
.calcBSplinePoint( p : number, U : Array.<number>, P : Array.<Vector4>, u : number ) : Vector4 (inner)
Calculates B-Spline curve points. See The NURBS Book, page 82, algorithm A3.1.
| p |
The degree of the B-Spline. |
| U |
The knot vector. |
| P |
The control points |
| u |
The parametric point. |
- Returns: The point for given
u.
.calcBasisFunctionDerivatives( span : number, u : number, p : number, n : number, U : Array.<number> ) : Array.<Array.<number>> (inner)
Calculates basis functions derivatives. See The NURBS Book, page 72, algorithm A2.3.
| span |
The span in which |
| u |
The parametric point. |
| p |
The degree. |
| n |
number of derivatives to calculate |
| U |
The knot vector. |
- Returns: An array[n+1][p+1] with basis functions derivatives.
.calcBasisFunctions( span : number, u : number, p : number, U : Array.<number> ) : Array.<number> (inner)
Calculates basis functions. See The NURBS Book, page 70, algorithm A2.2.
| span |
The span in which |
| u |
The parametric value. |
| p |
The degree. |
| U |
The knot vector. |
- Returns: Array[p+1] with basis functions values.
.calcKoverI( k : number, i : number ) : number (inner)
Calculates "K over I".
| k |
The K value. |
| i |
The I value. |
- Returns: k!/(i!(k-i)!)
.calcNURBSDerivatives( p : number, U : Array.<number>, P : Array.<Vector4>, u : number, nd : number ) : Array.<Vector3> (inner)
Calculates NURBS curve derivatives. See The NURBS Book, page 127, algorithm A4.2.
| p |
The degree. |
| U |
The knot vector. |
| P |
The control points in homogeneous space. |
| u |
The parametric point. |
| nd |
The number of derivatives. |
- Returns: array with derivatives for rational curve.
.calcRationalCurveDerivatives( Pders : Array.<Vector4> ) : Array.<Vector3> (inner)
Calculates derivatives (0-nd) of rational curve. See The NURBS Book, page 127, algorithm A4.2.
| Pders |
Array with derivatives. |
- Returns: An array with derivatives for rational curve.
.calcSurfacePoint( p : number, q : number, U : Array.<number>, V : Array.<number>, P : Array.<Array.<Vector4>>, u : number, v : number, target : Vector3 ) (inner)
Calculates a rational B-Spline surface point. See The NURBS Book, page 134, algorithm A4.3.
| p |
The first degree of B-Spline surface. |
| q |
The second degree of B-Spline surface. |
| U |
The first knot vector. |
| V |
The second knot vector. |
| P |
The control points in homogeneous space. |
| u |
The first parametric point. |
| v |
The second parametric point. |
| target |
The target vector. |
.calcVolumePoint( p : number, q : number, r : number, U : Array.<number>, V : Array.<number>, W : Array.<number>, P : Array.<Array.<Array.<Vector4>>>, u : number, v : number, w : number, target : Vector3 ) (inner)
Calculates a rational B-Spline volume point. See The NURBS Book, page 134, algorithm A4.3.
| p |
The first degree of B-Spline surface. |
| q |
The second degree of B-Spline surface. |
| r |
The third degree of B-Spline surface. |
| U |
The first knot vector. |
| V |
The second knot vector. |
| W |
The third knot vector. |
| P |
The control points in homogeneous space. |
| u |
The first parametric point. |
| v |
The second parametric point. |
| w |
The third parametric point. |
| target |
The target vector. |
.findSpan( p : number, u : number, U : Array.<number> ) : number (inner)
Finds knot vector span.
| p |
The degree. |
| u |
The parametric value. |
| U |
The knot vector. |
- Returns: The span.