thank you every much, your code worked！ It cost 3 percent of the previous time。
I have another question want to ask you, I use the following code
// _pd is a vtkPolyData object only with points
// the code is c#
var delaunay = vtkDelaunay2D.New();
delaunay.SetTolerance(0.001);
delaunay.SetInput(_pd);
delaunay.Update();
the above code cost 100 millisecond level while the _pd have 10,000 points,.
So i use c++ CGAL build delaunay2D ， in c++ code, CGAL build delaunay2D cost 10 ms level with the same points. Then I Pass cell information to c#.
I think I’m using it wrong, can you tell me how to speed up the delaunay2D of vtk? I just need cell and point information。