fix(modeling): added geom3.fromPointsConvex()

packages/modeling/src/geometries/geom3/fromPointsConvex.d.ts

@@ -0,0 +1,4 @@
+import type { Geom3 } from './type.d.ts'
+import type { Vec3 } from '../../maths/vec3/type.d.ts'
+
+export function fromPointsConvex(points: Array<Array<Vec3>>): Geom3

packages/modeling/src/geometries/geom3/fromPointsConvex.js

@@ -0,0 +1,25 @@
+import { runner } from '../../quickhull/index.js'
+import { create } from './create.js'
+import * as poly3 from '../poly3/index.js'
+
+/**
+ * Construct a new convex 3D geometry from a list of unique points.
+ *
+ * @param {Array} uniquePoints - list of points to construct convex 3D geometry
+ * @returns {geom3} a new geometry
+ * @alias module:modeling/geometries/geom3.fromPointsConvex
+ */
+export const fromPointsConvex = (uniquePoints) => {
+  if (!Array.isArray(uniquePoints)) {
+    throw new Error('the given points must be an array')
+  }
+
+  const faces = runner(uniquePoints, { skipTriangulation: true })
+
+  const polygons = faces.map((face) => {
+    const vertices = face.map((index) => uniquePoints[index])
+    return poly3.create(vertices)
+  })
+
+  return create(polygons)
+}

packages/modeling/src/geometries/geom3/fromPointsConvex.test.js

@@ -0,0 +1,28 @@
+import test from 'ava'
+
+import { fromPointsConvex, validate } from './index.js'
+
+test('fromPointsConvex (uniquePoints)', (t) => {
+  let out = []
+  for(x=-9;x<=9;++x)
+    for(y=-9;y<=9;++y)
+     for(z=-9;z<=9;++z)
+        if (x*x+y*y+z*z <= 96)
+          out.push([x,y,z])
+
+  let obs = fromPointsConvex(out)
+  validate(obs)
+  t.is(obs.polygons.length, 170)
+  t.true(obs.polygons.every((f) => ([3,4,8,9].indexOf(f.vertices.length) !== -1)))
+
+  let c = [0,0,0,0,0,0,0,0,0,0]
+  obs.polygons.forEach((f) => c[f.vertices.length]++)
+  t.is(c[3], 120);
+  t.is(c[4], 24);
+  t.is(c[8], 18);
+  t.is(c[9], 8);
+
+  let edges2 = 336*2
+  obs.polygons.forEach((f) => edges2 -= f.vertices.length)
+  t.is(edges2, 0);
+})

packages/modeling/src/geometries/geom3/index.d.ts

@@ -1,6 +1,7 @@
 export { clone } from './clone.js'
 export { create } from './create.js'
 export { fromPoints } from './fromPoints.js'
+export { fromPointsConvex } from './fromPointsConvex.js'
 export { fromCompactBinary } from './fromCompactBinary.js'
 export { invert } from './invert.js'
 export { isA } from './isA.js'

packages/modeling/src/geometries/geom3/index.js

@@ -17,6 +17,7 @@
 export { clone } from './clone.js'
 export { create } from './create.js'
 export { fromPoints } from './fromPoints.js'
+export { fromPointsConvex } from './fromPointsConvex.js'
 export { fromCompactBinary } from './fromCompactBinary.js'
 export { invert } from './invert.js'
 export { isA } from './isA.js'