@jscad/modeling/src/operations/modifiers/reTesselateCoplanarPolygons.test.js

Constructive Solid Geometry (CSG) Library for JSCAD

const test = require('ava')

const mat4 = require('../../maths/mat4')

const { poly3 } = require('../../geometries')

const reTesselateCoplanarPolygons = require('./reTesselateCoplanarPolygons')

const translatePoly3 = (offsets, polygon) => {
  const matrix = mat4.fromTranslation(mat4.create(), offsets)
  return poly3.transform(matrix, polygon)
}

const rotatePoly3 = (angles, polygon) => {
  const matrix = mat4.fromTaitBryanRotation(mat4.create(), (angles[0] * 0.017453292519943295), (angles[1] * 0.017453292519943295), (angles[2] * 0.017453292519943295))
  return poly3.transform(matrix, polygon)
}

test.only('retessellateCoplanarPolygons: should merge coplanar polygons', (t) => {
  const polyA = poly3.create([[-5, -5, 0], [5, -5, 0], [5, 5, 0], [-5, 5, 0]])
  const polyB = poly3.create([[5, -5, 0], [8, 0, 0], [5, 5, 0]])
  const polyC = poly3.create([[-5, 5, 0], [-8, 0, 0], [-5, -5, 0]])
  const polyD = poly3.create([[-5, 5, 0], [5, 5, 0], [0, 8, 0]])
  const polyE = poly3.create([[5, -5, 0], [-5, -5, 0], [0, -8, 0]])

  // combine polygons in each direction
  let obs = reTesselateCoplanarPolygons([polyA, polyB])
  t.is(obs.length, 1)
  obs = reTesselateCoplanarPolygons([polyA, polyC])
  t.is(obs.length, 1)
  obs = reTesselateCoplanarPolygons([polyA, polyD])
  t.is(obs.length, 1)
  obs = reTesselateCoplanarPolygons([polyA, polyE])
  t.is(obs.length, 1)

  // combine several polygons in each direction
  obs = reTesselateCoplanarPolygons([polyB, polyA, polyC])
  t.is(obs.length, 1)
  obs = reTesselateCoplanarPolygons([polyC, polyA, polyB])
  t.is(obs.length, 1)

  obs = reTesselateCoplanarPolygons([polyD, polyA, polyE])
  t.is(obs.length, 1)
  obs = reTesselateCoplanarPolygons([polyE, polyA, polyD])
  t.is(obs.length, 1)

  // combine all polygons
  obs = reTesselateCoplanarPolygons([polyA, polyB, polyC, polyD, polyE])
  t.is(obs.length, 1)

  // now rotate everything and do again
  let polyH = rotatePoly3([-45, -45, -45], polyA)
  let polyI = rotatePoly3([-45, -45, -45], polyB)
  let polyJ = rotatePoly3([-45, -45, -45], polyC)
  let polyK = rotatePoly3([-45, -45, -45], polyD)
  let polyL = rotatePoly3([-45, -45, -45], polyE)

  obs = reTesselateCoplanarPolygons([polyH, polyI, polyJ, polyK, polyL])
  t.is(obs.length, 1)

  // now translate everything and do again
  polyH = translatePoly3([-15, -15, -15], polyA)
  polyI = translatePoly3([-15, -15, -15], polyB)
  polyJ = translatePoly3([-15, -15, -15], polyC)
  polyK = translatePoly3([-15, -15, -15], polyD)
  polyL = translatePoly3([-15, -15, -15], polyE)

  obs = reTesselateCoplanarPolygons([polyH, polyI, polyJ, polyK, polyL])
  t.is(obs.length, 1)
})