three.js/src/extras/core/Path.js

import { Vector2 } from '../../math/Vector2.js';
import { CurvePath } from './CurvePath.js';
import { EllipseCurve } from '../curves/EllipseCurve.js';
import { SplineCurve } from '../curves/SplineCurve.js';
import { CubicBezierCurve } from '../curves/CubicBezierCurve.js';
import { QuadraticBezierCurve } from '../curves/QuadraticBezierCurve.js';
import { LineCurve } from '../curves/LineCurve.js';

function Path( points ) {

	CurvePath.call( this );

	this.type = 'Path';

	this.currentPoint = new Vector2();

	if ( points ) {

		this.setFromPoints( points );

	}

}

Path.prototype = Object.assign( Object.create( CurvePath.prototype ), {

	constructor: Path,

	setFromPoints: function ( points ) {

		this.moveTo( points[ 0 ].x, points[ 0 ].y );

		for ( let i = 1, l = points.length; i < l; i ++ ) {

			this.lineTo( points[ i ].x, points[ i ].y );

		}

		return this;

	},

	moveTo: function ( x, y ) {

		this.currentPoint.set( x, y ); // TODO consider referencing vectors instead of copying?

		return this;

	},

	lineTo: function ( x, y ) {

		const curve = new LineCurve( this.currentPoint.clone(), new Vector2( x, y ) );
		this.curves.push( curve );

		this.currentPoint.set( x, y );

		return this;

	},

	quadraticCurveTo: function ( aCPx, aCPy, aX, aY ) {

		const curve = new QuadraticBezierCurve(
			this.currentPoint.clone(),
			new Vector2( aCPx, aCPy ),
			new Vector2( aX, aY )
		);

		this.curves.push( curve );

		this.currentPoint.set( aX, aY );

		return this;

	},

	bezierCurveTo: function ( aCP1x, aCP1y, aCP2x, aCP2y, aX, aY ) {

		const curve = new CubicBezierCurve(
			this.currentPoint.clone(),
			new Vector2( aCP1x, aCP1y ),
			new Vector2( aCP2x, aCP2y ),
			new Vector2( aX, aY )
		);

		this.curves.push( curve );

		this.currentPoint.set( aX, aY );

		return this;

	},

	splineThru: function ( pts /*Array of Vector*/ ) {

		const npts = [ this.currentPoint.clone() ].concat( pts );

		const curve = new SplineCurve( npts );
		this.curves.push( curve );

		this.currentPoint.copy( pts[ pts.length - 1 ] );

		return this;

	},

	arc: function ( aX, aY, aRadius, aStartAngle, aEndAngle, aClockwise ) {

		const x0 = this.currentPoint.x;
		const y0 = this.currentPoint.y;

		this.absarc( aX + x0, aY + y0, aRadius,
			aStartAngle, aEndAngle, aClockwise );

		return this;

	},

	absarc: function ( aX, aY, aRadius, aStartAngle, aEndAngle, aClockwise ) {

		this.absellipse( aX, aY, aRadius, aRadius, aStartAngle, aEndAngle, aClockwise );

		return this;

	},

	ellipse: function ( aX, aY, xRadius, yRadius, aStartAngle, aEndAngle, aClockwise, aRotation ) {

		const x0 = this.currentPoint.x;
		const y0 = this.currentPoint.y;

		this.absellipse( aX + x0, aY + y0, xRadius, yRadius, aStartAngle, aEndAngle, aClockwise, aRotation );

		return this;

	},

	absellipse: function ( aX, aY, xRadius, yRadius, aStartAngle, aEndAngle, aClockwise, aRotation ) {

		const curve = new EllipseCurve( aX, aY, xRadius, yRadius, aStartAngle, aEndAngle, aClockwise, aRotation );

		if ( this.curves.length > 0 ) {

			// if a previous curve is present, attempt to join
			const firstPoint = curve.getPoint( 0 );

			if ( ! firstPoint.equals( this.currentPoint ) ) {

				this.lineTo( firstPoint.x, firstPoint.y );

			}

		}

		this.curves.push( curve );

		const lastPoint = curve.getPoint( 1 );
		this.currentPoint.copy( lastPoint );

		return this;

	},

	copy: function ( source ) {

		CurvePath.prototype.copy.call( this, source );

		this.currentPoint.copy( source.currentPoint );

		return this;

	},

	toJSON: function () {

		const data = CurvePath.prototype.toJSON.call( this );

		data.currentPoint = this.currentPoint.toArray();

		return data;

	},

	fromJSON: function ( json ) {

		CurvePath.prototype.fromJSON.call( this, json );

		this.currentPoint.fromArray( json.currentPoint );

		return this;

	}

} );


export { Path };