Question How to fix vertices after probuilder polymesh substract method?

Hello everyone,

We are making our own navmesh, that's why i made a mesh tool to edit and create new meshes. I use
https://github.com/karl-/pb_CSG this library (probuilder external library) to cutting polygons.
Cutting is perfect, i can get perfect final touch.

But problem is after cutting my mesh is looks like that:




I snapped vertices and triangles and still my vertices here:




Because of these complicated vertices, navmesh working wrong.


My snap code is here:

Code (CSharp):

1. snappedVertices.Clear();
2.     vertices.Clear();
3.     indices.Clear();
4.  
5.     for(int i = 0; i < meshFilter.sharedMesh.vertices.Length; i++) {
6.       var next = new Vector3(meshFilter.sharedMesh.vertices[i].x, 0, meshFilter.sharedMesh.vertices[i].z);
7.       vertices.Add(next);
8.     }
9.  
10.     foreach(var v in vertices) {
11.       snappedVertices.Add(v);
12.     }
13.  
14.  
15.     for(int i = 0; i < snappedVertices.Count; i++) {
16.       clearClosestVertices(i, snappedVertices[i]);
17.     }
18.  
19.     snappedVertices = snappedVertices.Distinct().ToList();
20.  
21.     indices = meshFilter.sharedMesh.triangles.ToList();
22.  
23.     Func<Vector3, (Vector3, int)> getClosest = (Vector3 p) => {
24.       float closestDistance = float.MaxValue;
25.       Vector3 closestVector = Vector3.zero;
26.       int closestIndex = 0;
27.  
28.       for (int i  = 0; i < snappedVertices.Count; i++) {
29.         var diff = p - snappedVertices[i];
30.         if (diff.sqrMagnitude < closestDistance) {
31.           closestDistance = diff.sqrMagnitude;
32.           closestVector = snappedVertices[i];
33.           closestIndex = i;
34.         }
35.       }
36.  
37.       return (closestVector, closestIndex);
38.     };
39.  
40.     newIndices = new List<int>();
41.  
42.     foreach(var v in indices.Select(i => vertices[i])) {
43.       newIndices.Add(getClosest(v).Item2);
44.     }
45.  
46.     meshFilter.sharedMesh.triangles = newIndices.ToArray();
47.     meshFilter.sharedMesh.vertices = snappedVertices.ToArray();
48.  
49.     meshFilter.sharedMesh.UploadMeshData(false);

I've tried vertex welding but i did not work.

Any idea? What can i do?