Add PolyDataToImageDataConverter.py based on PolyDataToImageDataStencil

src/Python.md

@@ -42,6 +42,7 @@ If you are new to VTK then these [tutorials](#tutorial) will help to get you sta
 | -------------- | ------------- | ------- |
 [CSVReadEdit](/Python/IO/CSVReadEdit) | Read and edit a CSV file using pandas and numpy.
 [CSVReadEdit1](/Python/IO/CSVReadEdit1) | Read and edit a CSV file using pandas and vtkDelimitedTextReader.
+[PolyDataToImageDataConverter](/Python/IO/PolyDataToImageDataConverter) | Converts PolyData to binary LabelImage.
 [ReadExodusData](/Python/IO/ReadExodusData) | A simple script for reading and viewing ExodusII data interactively.
 [ReadPLOT3D](/Python/IO/ReadPLOT3D) | Read CFD (computational fluid dynamics) data produced by PLOT3D.
 [ReadSLC](/Python/IO/ReadSLC) | Read an SLC file.

src/Python/IO/PolyDataToImageDataConverter.py

+#!/usr/bin/env python
+
+from vtkmodules.vtkCommonDataModel import vtkImageData
+from vtkmodules.vtkIOGeometry import vtkSTLReader
+from vtkmodules.vtkIOImage import vtkMetaImageWriter
+from vtkmodules.vtkImagingStencil import (
+    vtkImageStencil,
+    vtkPolyDataToImageStencil
+)
+
+
+def get_program_parameters():
+    import argparse
+    parser = argparse.ArgumentParser(description='Converts the polydata to imagedata.')
+    parser.add_argument('filename', help='A filename e.g. headMesh.stl')
+    args = parser.parse_args()
+    return args.filename
+
+
+def main():
+    mesh_filename = get_program_parameters()
+
+    reader = vtkSTLReader()
+    reader.SetFileName(mesh_filename)
+    reader.Update()
+    mesh = reader.GetOutput()
+    bounds = mesh.GetBounds()
+
+    spacing1 = 0.1
+    pixel_padding = 5
+    origin_shift = pixel_padding * spacing1
+    spacing = [spacing1, spacing1, spacing1]
+    origin = [bounds[0] - origin_shift, bounds[2] - origin_shift, bounds[4] - origin_shift]
+    extent = [0, int((bounds[1] - bounds[0]) / spacing1) + 2 * pixel_padding, 0,
+              int((bounds[3] - bounds[2]) / spacing1) + 2 * pixel_padding, 0,
+              int((bounds[5] - bounds[4]) / spacing1) + 2 * pixel_padding]
+
+    blank_image = vtkImageData()
+    blank_image.SetExtent(extent)
+    blank_image.AllocateScalars(3, 1)  # VTK_UNSIGNED_CHAR, 1 component
+    blank_image.GetPointData().GetScalars().Fill(0)
+    blank_image.SetSpacing(spacing)
+    blank_image.SetOrigin(origin)
+
+    dataToStencil = vtkPolyDataToImageStencil()
+    dataToStencil.SetInputData(mesh)
+    dataToStencil.SetOutputSpacing(spacing)
+    dataToStencil.SetOutputOrigin(origin)
+
+    stencil = vtkImageStencil()
+    stencil.SetInputData(blank_image)
+    stencil.SetStencilConnection(dataToStencil.GetOutputPort())
+    stencil.ReverseStencilOn()
+    stencil.SetBackgroundValue(255)
+    stencil.Update()
+    mask = stencil.GetOutput()
+
+    writer = vtkMetaImageWriter()
+    writer.SetFileName("output.mha")
+    writer.SetInputData(mask)
+    writer.Write()
+
+
+if __name__ == '__main__':
+    main()