Improve example coverage of plotting module

About 50% of our docstrings in PyVista have examples. This is fairly good, especially considering that many of these objects are not publicly exposed.

However, for modules like pyvista.plotting.plotting, it would be great to see nearly 100% coverage considering how important it is to be able to demonstrate the individual methods of the Plotting class.

This is a great first issue since it doesn’t involve changing the code base, just providing an example for some of our docstrings in plotting

Feel free to post questions here on how to get started if you’re interested.

Note that many of these examples don’t need to include plotter.show, and if they write files you can feel free to use the # doctest:+SKIP directive

Name                                         Docstrings     Missed   Covered
----------------------------------------------------------------------------
pyvista.plotting.plotting                           155        110     29.0%

Some easy ones

• Plotter.export_vtkjs
• Plotter.fly_to
• Plotter.remove_legend
• Plotter.save_graphic
• Plotter.add_point_labels
• Plotter.add_lines
• Plotter.add_text
• Plotter.add_legend (needs to be fixed, plots aren’t great)
• Plotter.add_point_scalar_labels
• Plotter.add_volume
• Plotter.increment_point_size_and_line_width
• Plotter.link_views
• remove_background_image
• remove_bounds_axes
• Plotter.remove_scalar_bar
• Plotter.render
• Plotter.reset_camera_clipping_range
• Plotter.set_environment_texture
• Plotter.show_axes_all
• Plotter.show_grid
• Plotter.view_xy
• Plotter.view_xz
• Plotter.view_yx
• Plotter.view_yz
• Plotter.view_zx
• Plotter.view_zy

Attributes:

• Plotter.background_color
• Plotter.bounds
• Plotter.camera
• Plotter.camera_position
• Plotter.center
• Plotter.image

Harder ones

• Plotter.add_actor

In widgets.py but exposed in Plotter

• add_box_widget
• add_checkbox_button_widget
• add_line_widget
• add_mesh_clip_box
• add_mesh_clip_plane
• add_mesh_isovalue
• add_mesh_slice
• add_mesh_slice_orthogonal
• add_mesh_slice_spline
• add_mesh_threshold
• add_plane_widget
• add_sphere_widget
• add_spline_widget
• add_text_slider_widget

Note that if we use the @wraps decorator, we need to make the changes to the docstring in the method being wrapped.

[adeak]

I’ve ticked out Plotter.add_volume(), thanks to @puripant, our newest contributor 🎉

[tkoyama010]

This is probably the BEST FIRST ISSUE. Thank you very much.