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three

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JavaScript 3D library

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import { Line } from './Line.js'; import { Vector3 } from '../math/Vector3.js'; import { Float32BufferAttribute } from '../core/BufferAttribute.js'; const _start = /*@__PURE__*/ new Vector3(); const _end = /*@__PURE__*/ new Vector3(); /** * A series of lines drawn between pairs of vertices. * * @augments Line */ class LineSegments extends Line { /** * Constructs a new line segments. * * @param {BufferGeometry} [geometry] - The line geometry. * @param {Material|Array<Material>} [material] - The line material. */ constructor( geometry, material ) { super( geometry, material ); /** * This flag can be used for type testing. * * @type {boolean} * @readonly * @default true */ this.isLineSegments = true; this.type = 'LineSegments'; } computeLineDistances() { const geometry = this.geometry; // we assume non-indexed geometry if ( geometry.index === null ) { const positionAttribute = geometry.attributes.position; const lineDistances = []; for ( let i = 0, l = positionAttribute.count; i < l; i += 2 ) { _start.fromBufferAttribute( positionAttribute, i ); _end.fromBufferAttribute( positionAttribute, i + 1 ); lineDistances[ i ] = ( i === 0 ) ? 0 : lineDistances[ i - 1 ]; lineDistances[ i + 1 ] = lineDistances[ i ] + _start.distanceTo( _end ); } geometry.setAttribute( 'lineDistance', new Float32BufferAttribute( lineDistances, 1 ) ); } else { console.warn( 'THREE.LineSegments.computeLineDistances(): Computation only possible with non-indexed BufferGeometry.' ); } return this; } } export { LineSegments };