print_ctf_dig_pts.py

from mne import read_trans
from mne import io
import os.path as op

from mne.io.constants import FIFF
from mne.transforms import apply_trans, combine_transforms

ds_fname = 'test.ds'
meas_fname = '%s-info.fif' % op.splitext(ds_fname)[0]

# save the measurement info so use in mne coreg...
raw = io.read_raw_ctf(ds_fname, preload=False)
io.write_info(meas_fname, raw.info)

# run mne coreg...

# read in the transformation that you save in mne coreg
trans_fname = 'test-trans.fif'
trans = read_trans(trans_fname)

# Print out the points
# collect points and labels to write.
info = raw.info
labels = []
pts = []
for p in info['dig']:
    if p['kind'] not in [FIFF.FIFFV_POINT_CARDINAL,
                         FIFF.FIFFV_POINT_EXTRA]:
        continue

    # pick label
    if p['kind'] == FIFF.FIFFV_POINT_CARDINAL:
        if p['ident'] == FIFF.FIFFV_POINT_LPA:
            labels.append('MEG_HPI_LPA')
        elif p['ident'] == FIFF.FIFFV_POINT_NASION:
            labels.append('MEG_HPI_NASION')
        elif p['ident'] == FIFF.FIFFV_POINT_RPA:
            labels.append('MEG_HPI_RPA')
        else:
            labels.append('MEG_HPI_OTHER?')
    elif p['kind'] == FIFF.FIFFV_POINT_EXTRA:
        if p['ident'] == 2000:
            labels.append('POL_HPI_LPA')
        elif p['ident'] == 2001:
            labels.append('POL_HPI_NASION')
        elif p['ident'] == 2002:
            labels.append('POL_HPI_RPA')
        else:
            labels.append('POL_EXTRA_%d' % p['ident'])

    # pick point FIFFV_MNE_COORD_CTF_HEAD
    if p['coord_frame'] == FIFF.FIFFV_COORD_HEAD:
        pts.append(apply_trans(trans, p['r']))
    elif p['coord_frame'] == FIFF.FIFFV_COORD_MRI:
        pts.append(p['r'])
    elif p['coord_frame'] == FIFF.FIFFV_MNE_COORD_CTF_HEAD:
        pts.append(apply_trans(trans, p['r']))
#             pts.append(apply_trans(ctf_trans, p['r']))

for l, p in zip(labels, pts):
    print ("%15s - %0.3f, %0.3f, %0.3f" % (l, p[0], p[1], p[2]))