[BUG, MRG] Fix pial surface loading, logging in locate_ieeg

[alexrockhill]

Fixes #11484

[alexrockhill]

Here's a minimal script to check

import os.path as op
import numpy as np

import nibabel as nib
from dipy.align import resample

import mne

misc_path = mne.datasets.misc.data_path()
subject = 'sample_seeg'
subjects_dir = op.join(misc_path, 'seeg')

CT_orig = nib.load(op.join(misc_path, 'seeg', 'sample_seeg_CT.mgz'))
raw = mne.io.read_raw(op.join(misc_path, 'seeg', 'sample_seeg_ieeg.fif'))

T1 = nib.load(op.join(misc_path, 'seeg', 'sample_seeg', 'mri', 'T1.mgz'))
reg_affine = np.array([
    [0.99270756, -0.03243313, 0.11610254, -133.094156],
    [0.04374389, 0.99439665, -0.09623816, -97.58320673],
    [-0.11233068, 0.10061512, 0.98856381, -84.45551601],
    [0., 0., 0., 1.]])
CT_aligned = mne.transforms.apply_volume_registration(CT_orig, T1, reg_affine)

trans = mne.coreg.estimate_head_mri_t(subject, subjects_dir)
gui = mne.gui.locate_ieeg(raw.info, trans, CT_aligned, subject=subject, subjects_dir=subjects_dir)

[alexrockhill]

Ok to merge @drammock @mmagnuski?

[drammock]

you've used this trick elsewhere too, right? The extra '' at the end just makes the error message cleaner? If that's right, can you just add a comment explaining, commit with ci skip, then merge?

[alexrockhill]

Yes, that's correct, will do