Extract surface and keep numbering

I believe the easiest solution is for you to create a field that contains the id of each point in the mesh. Then when you run Extract Surface, the field of ids will be permuted appropriately. The easiest way to create ids for points (and cells) is to use the Generate Ids filter.

So, to run Extract Surface while preserving the initial point ids, do the following.

  1. Add the Generate Ids filter. Apply.
  2. Add the Extract Surface filter. Apply.

The result of Extract Surface will have a point id field containing the original point ids.