clip entire plot at a given elevation with slider

[laserman781]

I have points and lined that are viewed together on a plot using pyvista.plotter and adding a mesh. I am having difficulty

Code:

p = pv.Plotter(notebook=False)
p.add_mesh(points,color='blue',render_points_as_spheres=all)
for i in range(0, len(DH)):
    p.add_mesh(globals()['segment{}'.format(i)],color='white',)
p.view_yz()
p.show_axes()

clipper = pv.Clip(p,plotter=p)

[banesullivan]

Hi @Quadius - at this time, clipping an entire scene is not implemented and the pyvista.Clip tool only handles a single mesh in the scene. I could hack together a solution for you soon here but not immediately.

The errors you are experiencing have to do with the arguments for the Clip tool. It takes the mesh you'd like to clip and an optional BackgroundPlotter object (not a standard Plotter).

Try this in the meantime:

p = pv.BackgroundPlotter()
for i in range(0, len(DH)):
    p.add_mesh(globals()['segment{}'.format(i)],color='white',)
p.view_yz()
p.show_axes()

clipper = pv.Clip(points, plotter=p, display_params=dict(color='blue', 
                                                         render_points_as_spheres=True))

[banesullivan]

Also, reference this currently closed issue: pyvista/pyvista#162

[laserman781]

Basically, I have rendered each line using pv.Line and each point using PolyData. Maybe I could combine all of them into one vtk object so I can then clip at a given elevation? Also, with your last solution I received the following without any viewer:

[banesullivan]

Also, with your last solution I received the following without any viewer

Sometimes the BackgroundPlotter appears in the background behind your current application (which is not intended given the name - the "Background" refers to the fact that it runs in a background thread)

[banesullivan]

Basically, I have rendered each line using pv.Line and each point using PolyData. Maybe I could combine all of them into one vtk object so I can then clip at a given elevation?

Ah, yes!! You could easily merge these all into one pyvista.UnstructuredGrid - there are a few ways to do this...

1. Create a pyvista.MultiBlock dataset containing everything and run its .comine() filter

blocks = pv.MultiBlock
blocks.append(points)
for i in range(0, len(DH)):
    blocks.append(globals()['segment{}'.format(i)])
merged = blocks.combine()

2. Use the .boolean_add() filter on the PolyData objects or the + operator which is pretty nifty (if poth inputs are PolyData):

merged = points.copy()
for i in range(0, len(DH)):
   merged = merged + globals()['segment{}'.format(i)]

[banesullivan]

Then if you still want to color the points and the line segments differently, you could add scalar values to them before merging:

import numpy as np
points['chunk'] = np.zeros(points.n_points)
for i in range(0, len(DH)):
    m = globals()['segment{}'.format(i)]
    m['chunk'] = np.ones(m.n_points)

Then when plotting the merged grid, simply choose a colormap (cmap) that you like, specify n_colors=2, and make sure the scalars are set to 'chunk'