Expose BandedPolyDataContourFilter

[akaszynski]

Expose vtk.vtkBandedPolyDataContourFilter. It's similar to vtkContourFilter, but different enough to necessate creating a new method as it's only applicable to PolyData.

Example:

Extract the surface from the uniform grid dataset and plot its contours
alongside the output from the banded contour filter.

import pyvista as pv
from pyvista import examples
surf = examples.load_uniform().extract_surface()
output, edges = surf.contour_banded(5, rng=[200, 500])
pl = pv.Plotter()
_ = pl.add_mesh(edges, line_width=5, render_lines_as_tubes=True, color='k')
_ = pl.add_mesh(surf, opacity=0.3, show_scalar_bar=False)
_ = pl.add_mesh(output)
pl.show()

[codecov]

Codecov Report

Merging #3606 (37b5a35) into main (91eff74) will decrease coverage by 0.00%.
The diff coverage is 93.33%.

@@            Coverage Diff             @@
##             main    #3606      +/-   ##
==========================================
- Coverage   95.17%   95.17%   -0.01%     
==========================================
  Files          83       83              
  Lines       18579    18609      +30     
==========================================
+ Hits        17683    17711      +28     
- Misses        896      898       +2     

[banesullivan]

Indeed a bit different from the standard contour filter so happy to have this as a separate method thought I would've loved to have an return_edges argument do this..