ClosedSurface

#!/usr/bin/env python

import vtk


def get_program_parameters():
    import argparse
    description = 'Read a polydata file of a surface and determine if it is a closed surface.'
    epilogue = '''
   '''
    parser = argparse.ArgumentParser(description=description, epilog=epilogue,
                                     formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument('filename', help='Enter a polydata file e.g cow.g.')
    args = parser.parse_args()
    return args.filename


def ReadPolyData(file_name):
    import os
    path, extension = os.path.splitext(file_name)
    extension = extension.lower()
    if extension == ".ply":
        reader = vtk.vtkPLYReader()
        reader.SetFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    elif extension == ".vtp":
        reader = vtk.vtkXMLpoly_dataReader()
        reader.SetFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    elif extension == ".obj":
        reader = vtk.vtkOBJReader()
        reader.SetFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    elif extension == ".stl":
        reader = vtk.vtkSTLReader()
        reader.SetFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    elif extension == ".vtk":
        reader = vtk.vtkpoly_dataReader()
        reader.SetFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    elif extension == ".g":
        reader = vtk.vtkBYUReader()
        reader.SetGeometryFileName(file_name)
        reader.Update()
        poly_data = reader.GetOutput()
    else:
        # Return a None if the extension is unknown.
        poly_data = None
    return poly_data


def main():
    fn = get_program_parameters()
    polyData = ReadPolyData(fn)
    featureEdges = vtk.vtkFeatureEdges()
    featureEdges.FeatureEdgesOff()
    featureEdges.BoundaryEdgesOn()
    featureEdges.NonManifoldEdgesOn()
    featureEdges.SetInputData(polyData)
    featureEdges.Update()

    numberOfOpenEdges = featureEdges.GetOutput().GetNumberOfCells()

    if numberOfOpenEdges > 0:
        print(fn, ': Surface is not closed')
    else:
        print(fn, ': Surface is closed')


if __name__ == '__main__':
    main()