Thank you very much for your prompt reply！
Although CGAL’s delaunay is fast, there seems to be a problem.
As you see, this fig is CGAL Delaunay，When the data is not closed like this, the edges will have strange triangles
the same data vtk is
I haven’t looked at the source code of vtk, but I want to ask if this is related to the
delaunay.SetTolerance(0.001);
set by vtk，
I use fast-vtk-delaunay2d, Its performance is the same as cgal, and the reconstruction of this kind of data is not good.
As for the simultaneous use of vtk and cgal you said, I have already realized it. The point I’m struggling with now is this strange triangle, is there a good way to get rid of it?