"""

POV-Ray rendered crystal structure
==================================

Here, we show POV-Ray rendered images as shown in :mod:`ase.spacegroup`.
As an example, we start from a skutterudite structure.
This structure is visualised with the Cobalt atoms on the
corners. This can easily be accomplished with ASE using
:func:`ase.build.cut`. Below is the *origo* argument used to
put the Cobalt atom on the corners and *extend* to include all corner
and edge atoms, even those belonging to neighbouring unit cells.
"""

import ase.io as io
from ase.build import cut
from ase.spacegroup import crystal

a = 9.04
skutterudite = crystal(
    ('Co', 'Sb'),
    basis=[(0.25, 0.25, 0.25), (0.0, 0.335, 0.158)],
    spacegroup=204,
    cellpar=[a, a, a, 90, 90, 90],
)

# Create a new atoms instance with Co at origo including all atoms on the
# surface of the unit cell
cosb3 = cut(skutterudite, origo=(0.25, 0.25, 0.25), extend=1.01)

# Define the atomic bonds to show
bondatoms = []
symbols = cosb3.get_chemical_symbols()
for i in range(len(cosb3)):
    for j in range(i):
        if symbols[i] == symbols[j] == 'Co' and cosb3.get_distance(i, j) < 4.53:
            bondatoms.append((i, j))
        elif (
            symbols[i] == symbols[j] == 'Sb' and cosb3.get_distance(i, j) < 2.99
        ):
            bondatoms.append((i, j))

# Create nice-looking image using povray
renderer = io.write(
    'spacegroup-cosb3.pov',
    cosb3,
    rotation='90y',
    radii=0.4,
    povray_settings=dict(
        transparent=False,
        camera_type='perspective',
        canvas_width=320,
        bondlinewidth=0.07,
        bondatoms=bondatoms,
    ),
)

renderer.render()