Examples of Triangulation

Delauney triangulation of many points in xy plane

25 points >
compute convex hull of points: Point3d[] const hull: Point3d[] = [];
const interior: Point3d[] = [];
Point3dArray.computeConvexHullXY(points, hull, interior, true);
>
One step points: Point3d[] to Polyface const polyface = PolyfaceBuilder.pointsToTriangulatedPolyface(points);
IndexedPolyface with all the points triangulated. >

Unit Test

  • source: imodeljs\core\geometry\src\test\topology\InsertAndRetriangulateContext.test.ts
  • test name: "TriangulateInHull"
  • output: imodeljs\core\geometry\src\test\output\InsertAndRetriangulateContext\TriangulateInHull.imjs

Triangulate points "between linestrings"

4 and 6 sided polygons >
Same polygons displayed with <br>handles to indicate the two linestrings have edge subdivision mismatch <br> in addition to the different cornering angles >
triangles constructed "between" the polygons >
Same polygons, another mix of points along edges >
triangles constructed "between" the polygons >

Unit Test

  • source: imodeljs\core\geometry\src\test\Polyface\GreedyTriangulationBetweenLineStrings.test.ts
  • test set: describe("GreedyTriangulationBetweenLineStrings"
  • test name: quadStar
  • output: imodeljs\core\geometry\src\test\output\GreedyTriangulationBetweenLineStrings\quadStar.imjs

Last Updated: 22 March, 2021