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📄 NURBSSurface.js

📊 Analysis Summary

Metric Count
🔧 Functions 1
🧱 Classes 1
📦 Imports 1
📊 Variables & Constants 5

📚 Table of Contents

🛠️ File Location:

📂 examples/jsm/curves/NURBSSurface.js

📦 Imports

Name Source
Vector4 three

Variables & Constants

Name Type Kind Value Exported
len1 number let/var knots1.length - degree1 - 1 ✗
len2 number let/var knots2.length - degree2 - 1 ✗
point any let/var controlPoints[ i ][ j ] ✗
u number let/var this.knots1[ 0 ] + t1 * ( this.knots1[ this.knots1.length - 1 ] - this.knots1... ✗
v number let/var this.knots2[ 0 ] + t2 * ( this.knots2[ this.knots2.length - 1 ] - this.knots2... ✗

Functions

NURBSSurface.getPoint(t1: number, t2: number, target: Vector3): void

JSDoc: 

/**
     * This method returns a vector in 3D space for the given interpolation factor. This vector lies on the NURBS surface.
     *
     * @param {number} t1 - The first interpolation factor representing the `u` position on the surface. Must be in the range `[0,1]`.
     * @param {number} t2 - The second interpolation factor representing the `v` position on the surface. Must be in the range `[0,1]`.
     * @param {Vector3} target - The target vector the result is written to.
     */

Parameters:

  • t1 number
  • t2 number
  • target Vector3

Returns: void

Calls:

  • NURBSUtils.calcSurfacePoint
Code 
getPoint( t1, t2, target ) {

        const u = this.knots1[ 0 ] + t1 * ( this.knots1[ this.knots1.length - 1 ] - this.knots1[ 0 ] ); // linear mapping t1->u
        const v = this.knots2[ 0 ] + t2 * ( this.knots2[ this.knots2.length - 1 ] - this.knots2[ 0 ] ); // linear mapping t2->u

        NURBSUtils.calcSurfacePoint( this.degree1, this.degree2, this.knots1, this.knots2, this.controlPoints, u, v, target );

    }

Classes

NURBSSurface

Class Code 
class NURBSSurface {

    /**
     * Constructs a new NURBS surface.
     *
     * @param {number} degree1 - The first NURBS degree.
     * @param {number} degree2 - The second NURBS degree.
     * @param {Array<number>} knots1 - The first knots as a flat array of numbers.
     * @param {Array<number>} knots2 - The second knots as a flat array of numbers.
     * @param {Array<Array<Vector2|Vector3|Vector4>>} controlPoints - An array^2 holding control points.
     */
    constructor( degree1, degree2, knots1, knots2, controlPoints ) {

        /**
         * The first NURBS degree.
         *
         * @type {number}
         */
        this.degree1 = degree1;

        /**
         * The second NURBS degree.
         *
         * @type {number}
         */
        this.degree2 = degree2;

        /**
         * The first knots as a flat array of numbers.
         *
         * @type {Array<number>}
         */
        this.knots1 = knots1;

        /**
         * The second knots as a flat array of numbers.
         *
         * @type {Array<number>}
         */
        this.knots2 = knots2;

        /**
         *  An array holding arrays of control points.
         *
         * @type {Array<Array<Vector2|Vector3|Vector4>>}
         */
        this.controlPoints = [];

        const len1 = knots1.length - degree1 - 1;
        const len2 = knots2.length - degree2 - 1;

        // ensure Vector4 for control points
        for ( let i = 0; i < len1; ++ i ) {

            this.controlPoints[ i ] = [];

            for ( let j = 0; j < len2; ++ j ) {

                const point = controlPoints[ i ][ j ];
                this.controlPoints[ i ][ j ] = new Vector4( point.x, point.y, point.z, point.w );

            }

        }

    }

    /**
     * This method returns a vector in 3D space for the given interpolation factor. This vector lies on the NURBS surface.
     *
     * @param {number} t1 - The first interpolation factor representing the `u` position on the surface. Must be in the range `[0,1]`.
     * @param {number} t2 - The second interpolation factor representing the `v` position on the surface. Must be in the range `[0,1]`.
     * @param {Vector3} target - The target vector the result is written to.
     */
    getPoint( t1, t2, target ) {

        const u = this.knots1[ 0 ] + t1 * ( this.knots1[ this.knots1.length - 1 ] - this.knots1[ 0 ] ); // linear mapping t1->u
        const v = this.knots2[ 0 ] + t2 * ( this.knots2[ this.knots2.length - 1 ] - this.knots2[ 0 ] ); // linear mapping t2->u

        NURBSUtils.calcSurfacePoint( this.degree1, this.degree2, this.knots1, this.knots2, this.controlPoints, u, v, target );

    }

}

Methods

getPoint(t1: number, t2: number, target: Vector3): void
Code 
getPoint( t1, t2, target ) {

        const u = this.knots1[ 0 ] + t1 * ( this.knots1[ this.knots1.length - 1 ] - this.knots1[ 0 ] ); // linear mapping t1->u
        const v = this.knots2[ 0 ] + t2 * ( this.knots2[ this.knots2.length - 1 ] - this.knots2[ 0 ] ); // linear mapping t2->u

        NURBSUtils.calcSurfacePoint( this.degree1, this.degree2, this.knots1, this.knots2, this.controlPoints, u, v, target );

    }