@jscad/modeling/src/operations/expansions/expandGeom3.js

Constructive Solid Geometry (CSG) Library for JSCAD

const geom3 = require('../../geometries/geom3')

const union = require('../booleans/union')

const expandShell = require('./expandShell')

/*
 * Expand the given geometry (geom3) using the given options (if any).
 * @param {Object} options - options for expand
 * @param {Number} [options.delta=1] - delta (+/-) of expansion
 * @param {String} [options.corners='round'] - type corner to create during of expansion; round
 * @param {Integer} [options.segments=12] - number of segments when creating round corners
 * @param {geom3} geometry - the geometry to expand
 * @returns {geom3} expanded geometry
 */
const expandGeom3 = (options, geometry) => {
  const defaults = {
    delta: 1,
    corners: 'round',
    segments: 12
  }
  const { delta, corners, segments } = Object.assign({ }, defaults, options)

  if (!(corners === 'round')) {
    throw new Error('corners must be "round" for 3D geometries')
  }

  const polygons = geom3.toPolygons(geometry)
  if (polygons.length === 0) throw new Error('the given geometry cannot be empty')

  options = { delta, corners, segments }
  const expanded = expandShell(options, geometry)
  return union(geometry, expanded)
}

module.exports = expandGeom3