Chapter 359: NURBSCurve

Core Idea

This class represents a NURBS curve.

Implementation is based on (x, y [, z=0 [, w=1]]) control points with w=weight.

Key Concepts

• controlPoints : Array.<Vector4>: An array of control points.
• degree : number: The NURBS degree.
• endKnot : number: Index of the end knot into the knots array.
• knots : Array.<number>: The knots as a flat array of numbers.
• startKnot : number: Index of the start knot into the knots array.

Code Examples

import { NURBSCurve } from 'three/addons/curves/NURBSCurve.js';

• What it demonstrates: Typical usage of NURBSCurve.

Reference Tables

Constructor

Signature
`new NURBSCurve( degree : number, knots : Array.<number>, controlPoints : Array.<(Vector2

Properties

Property	Description
.controlPoints : Array.<Vector4>	An array of control points.
.degree : number	The NURBS degree.
.endKnot : number	Index of the end knot into the knots array.
.knots : Array.<number>	The knots as a flat array of numbers.
.startKnot : number	Index of the start knot into the knots array.

Methods

Method	Description
.getPoint( t : number, optionalTarget : Vector3 ) : Vector3	This method returns a vector in 3D space for the given interpolation factor.
.getTangent( t : number, optionalTarget : Vector3 ) : Vector3	Returns a unit vector tangent for the given interpolation factor.

Key Takeaways

1. NURBSCurve extends: Curve
2. Most relevant properties: controlPoints, degree, endKnot, knots.
3. Key methods: getPoint, getTangent.

Connects To

• Curve: parent class
• Source: examples/jsm/curves/NURBSCurve.js