Subsample polydata

I have a polydata with N_v vertices and N_f faces.
I have manually segmented regions (and know all corresponding vertices) which belong to their respective classes. How do I create “subsampled” polydata for these selection, i.e I would like to create sepereate meshes based on the the point_ID selections
My best guess was to use vtkGeometryFilter, where it mentions “It also is possible to specify conditions on point ids, cell ids, and on a bounding box (referred to as “Extent”) to control the extraction process”, but I do not find an option to provide the point ids

I think vtkThreshold is what you’re looking for? It can produce a new poly data for which all values within a certain range are provided. Either cell or point data. You can play around with it in Paraview as well.