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three

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JavaScript 3D library

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import { Curve } from '../core/Curve.js'; import { QuadraticBezier } from '../core/Interpolations.js'; import { Vector2 } from '../../math/Vector2.js'; /** * A curve representing a 2D Quadratic Bezier curve. * * ```js * const curve = new THREE.QuadraticBezierCurve( * new THREE.Vector2( - 10, 0 ), * new THREE.Vector2( 20, 15 ), * new THREE.Vector2( 10, 0 ) * ) * * const points = curve.getPoints( 50 ); * const geometry = new THREE.BufferGeometry().setFromPoints( points ); * * const material = new THREE.LineBasicMaterial( { color: 0xff0000 } ); * * // Create the final object to add to the scene * const curveObject = new THREE.Line( geometry, material ); * ``` * * @augments Curve */ class QuadraticBezierCurve extends Curve { /** * Constructs a new Quadratic Bezier curve. * * @param {Vector2} [v0] - The start point. * @param {Vector2} [v1] - The control point. * @param {Vector2} [v2] - The end point. */ constructor( v0 = new Vector2(), v1 = new Vector2(), v2 = new Vector2() ) { super(); /** * This flag can be used for type testing. * * @type {boolean} * @readonly * @default true */ this.isQuadraticBezierCurve = true; this.type = 'QuadraticBezierCurve'; /** * The start point. * * @type {Vector2} */ this.v0 = v0; /** * The control point. * * @type {Vector2} */ this.v1 = v1; /** * The end point. * * @type {Vector2} */ this.v2 = v2; } /** * Returns a point on the curve. * * @param {number} t - A interpolation factor representing a position on the curve. Must be in the range `[0,1]`. * @param {Vector2} [optionalTarget] - The optional target vector the result is written to. * @return {Vector2} The position on the curve. */ getPoint( t, optionalTarget = new Vector2() ) { const point = optionalTarget; const v0 = this.v0, v1 = this.v1, v2 = this.v2; point.set( QuadraticBezier( t, v0.x, v1.x, v2.x ), QuadraticBezier( t, v0.y, v1.y, v2.y ) ); return point; } copy( source ) { super.copy( source ); this.v0.copy( source.v0 ); this.v1.copy( source.v1 ); this.v2.copy( source.v2 ); return this; } toJSON() { const data = super.toJSON(); data.v0 = this.v0.toArray(); data.v1 = this.v1.toArray(); data.v2 = this.v2.toArray(); return data; } fromJSON( json ) { super.fromJSON( json ); this.v0.fromArray( json.v0 ); this.v1.fromArray( json.v1 ); this.v2.fromArray( json.v2 ); return this; } } export { QuadraticBezierCurve };