"""
===========================
Reading an inverse operator
===========================

The inverse operator's source space is shown in 3D.
"""
# Author: Alexandre Gramfort <alexandre.gramfort@telecom-paristech.fr>
#
# License: BSD (3-clause)

from mne.datasets import sample
from mne.minimum_norm import read_inverse_operator

print(__doc__)

data_path = sample.data_path()
fname = data_path
fname += '/MEG/sample/sample_audvis-meg-oct-6-meg-inv.fif'

inv = read_inverse_operator(fname)

print("Method: %s" % inv['methods'])
print("fMRI prior: %s" % inv['fmri_prior'])
print("Number of sources: %s" % inv['nsource'])
print("Number of channels: %s" % inv['nchan'])

###############################################################################
# Show result on 3D source space
lh_points = inv['src'][0]['rr']
lh_faces = inv['src'][0]['use_tris']
rh_points = inv['src'][1]['rr']
rh_faces = inv['src'][1]['use_tris']
from mayavi import mlab  # noqa

mlab.figure(size=(600, 600), bgcolor=(0, 0, 0))
mesh = mlab.triangular_mesh(lh_points[:, 0], lh_points[:, 1], lh_points[:, 2],
                            lh_faces, colormap='RdBu')
mesh.module_manager.scalar_lut_manager.reverse_lut = True

mesh = mlab.triangular_mesh(rh_points[:, 0], rh_points[:, 1], rh_points[:, 2],
                            rh_faces, colormap='RdBu')
mesh.module_manager.scalar_lut_manager.reverse_lut = True