// input points for a polygon2D contor
List<Vector2> points = new List<Vector2>();

// Add Vector2 to points
points.Add(new Vector2(-2.5f, -2.5f));
points.Add(new Vector2(2.5f, -2.5f));
points.Add(new Vector2(4.5f, 2.5f));
points.Add(new Vector2(0.5f, 4.5f));
points.Add(new Vector2(-3.5f, 2.5f));

// construct Polygon2D 
Polygon2D polygon = Polygon2D.Contour(points.ToArray());

// construct Triangulation2D with Polygon2D and threshold angle (18f ~ 27f recommended)
Triangulation2D triangulation = new Triangulation2D(polygon, 22.5f);

// build a mesh from triangles in a Triangulation2D instance
Mesh mesh = triangulation.Build();
// GetComponent<MeshFilter>().sharedMesh = mesh;