Enable fNIRS in coreg gui

[rob-luke]

Reference issue

Conversation started over in mne-tools/mne-nirs#419 and specifically this comment from @larsoner mne-tools/mne-nirs#419 (comment)

However, when I ran the coreg guy with fNIRS data no sensors were displayed.

What does this implement/fix?

Enables plotting of fNIRS sources and detectors in the coreg gui

Additional information

I am totally new to the whole coregistration concept. So please let me know if there is more I should look at.
Also I am new to guis, how do I test this change in the CI?

[rob-luke]

@GuillaumeFavelier @larsoner could you please review

[GuillaumeFavelier]

Hi @rob-luke , I'm +1 to add support for fNIRS if there is a need for it. I just wonder how to integrate it. For now we have one checkbox for each element to display (HSP, HPI, EEG), should we add one for fNIRS? Or are those always associated with EEG? Also, do we want to display them by default?

[larsoner]

Looks like a good start, and a reasonable direction!

It needs a test. One easy way to test this might be to take one of our existing coreg functions and set_channel_types to change the EEG channels to fNIRS ones. On main you should see that ._actors['eeg_channels'] is None and here it's not None. If that hack doesn't work, using some fNIRS file from testing would also work. (Maybe this is just cleaner anyway.)

[larsoner]

I thought about maybe having a separate fNIRS box for the weights for fNIRS, but really we should probably just change that to be "Sensors". In dig we don't have a separate entry for fNIRS dig points (they are called EEG even though they're not), and we might as well always show them if they're present I think, just like we do for EEG. fNIRS needs to be close to the scalp like EEG.

It'll get trickier with OPMs because you do typically want them up against the scalp, but the technology doesn't really require it (unlike fNIRS, where your signal will degrade much faster with distance from the scalp IIUC). But for now I think just adding fNIRS to what gets shown the same way EEG does is a good start.

[GuillaumeFavelier]

Suggested change

	sens_actors.append(actors["fnirs"])
	sens_actors.extend(actors["fnirs"])

This could deal with the issues with SetVisibillity()

[rob-luke]

Thanks @GuillaumeFavelier and @larsoner

I also see there is substantial and consistent work being done on the Coreg. Would it be better for this small change to be done via one of @GuillaumeFavelier PRs? Or maybe I should wait until development has stabilised? Or I should continue here? Any preference?

[larsoner]

I also see there is substantial and consistent work being done on the Coreg. Would it be better for this small change to be done via one of @GuillaumeFavelier PRs? Or maybe I should wait until development has stabilised? Or I should continue here? Any preference?

I'm fine with you adding fNIRS support things here, I don't mind a bad rebase/merge or two along the way in #10015 at least :)

[larsoner]

I don't mind a bad rebase/merge or two along the way in #10015 at least :)

Looks like it didn't even create a merge conflict. I think if you fix this then we can probably merge:

mne/gui/tests/test_coreg_gui.py:113: in test_coreg_gui_pyvista
    coreg = coregistration(inst=raw_path, subject='sample',
<decorator-gen-535>:24: in coregistration
    ???
mne/gui/__init__.py:195: in coregistration
    return CoregistrationUI(
mne/gui/_coreg.py:203: in __init__
    self._set_lock_fids(fid_accurate)
mne/gui/_coreg.py:223: in _set_lock_fids
    self._lock_fids = bool(state)
/usr/share/miniconda/envs/mne/lib/python3.9/site-packages/traitlets/traitlets.py:606: in __set__
    self.set(obj, value)
/usr/share/miniconda/envs/mne/lib/python3.9/site-packages/traitlets/traitlets.py:595: in set
    obj._notify_trait(self.name, old_value, new_value)
/usr/share/miniconda/envs/mne/lib/python3.9/site-packages/traitlets/traitlets.py:1219: in _notify_trait
    self.notify_change(Bunch(
/usr/share/miniconda/envs/mne/lib/python3.9/site-packages/traitlets/traitlets.py:1229: in notify_change
    return self._notify_observers(change)
/usr/share/miniconda/envs/mne/lib/python3.9/site-packages/traitlets/traitlets.py:1266: in _notify_observers
    c(event)
mne/gui/_coreg.py:352: in _lock_fids_changed
    self._set_sensors_visibility(self._lock_fids)
mne/gui/_coreg.py:605: in _set_sensors_visibility
    actor.SetVisibility(state)
E   AttributeError: 'list' object has no attribute 'SetVisibility'

[rob-luke]

Closed in favour of #10122