viz.plot_sensors('3d') doesn't handle mouse clicks to reveal sensor names correctly

MWE:

from pathlib import Path
import matplotlib
import mne

matplotlib.use('Qt5Agg')

sample_dir = Path(mne.datasets.sample.data_path())
sample_fname = sample_dir / 'MEG' / 'sample' / 'sample_audvis_raw.fif'

raw = mne.io.read_raw_fif(sample_fname, preload=False)
raw.plot_sensors('3d')

Clicking on the frontal sensors reveals names of channels someplace else.

https://user-images.githubusercontent.com/2046265/115535014-a6acc000-a298-11eb-881d-bacf661ee57d.mov

When show_names=True is passed, the channels are labeled correctly, though, leading me to believe that the odd behavior described above is related to click -> channel mapping

For completeness, here’s a 2D sensor plot:

macOS with Qt5 backend.

[drammock]

I played around a bit and have concluded that the event.ind returned by the matplotlib pick event is not deterministic and not stable before/after a click-drag rotation of the axes. Try it out: click on a point that you like, keep your eye on it while you rotate the axes, then click on that point again.

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
plt.ion()


def onpick(event):
    ind = event.ind
    print(f'index: {ind}')


x = np.tile(np.linspace(0, 1, 5), 3*7)
y = np.repeat(np.linspace(0, 1, 7), 3*5)
z = np.tile(np.linspace(0, 1, 3), 5*7)
c = np.linspace(0, 1, 3*5*7)
s = np.full(3*5*7, 100)

fig, ax = plt.subplots(subplot_kw=dict(projection='3d'))
ax.scatter(x, y, z, s=s, c=c, picker=True)
fig.canvas.mpl_connect('pick_event', onpick)

[larsoner]

I’m going to push to 0.24 since it seems like it might take a while to figure out the right solution here