o1, o2, o3
o1,
o2,
o3 describe the coordinates of the node
in the lower-left corner of the cell where the new origin is, calculated
with conventional or primitive cell vectors.
The cell position, given by the coordinates x,y,z of the origin node,
is not affected by a change in the origin node, so the new origin node
must occupy the position kept by the previous origin node, forcing a
cell translation. The new cell origin can be outside the current cell
volume.
Example: <cell ... o1="0" o2="0" o3="0"/> (default)
Allowed values: integer (optional, coupled)
o4
When the lattice is centered and vectors are conventional,
a fourth coordinate
o4 is needed to point the new origin
node (000) to one of the centered nodes. By default,
o4
is
000, so no change is introduced. When the cell lattice
is primitive
P or the vectors defining the origin are primitive,
that is the only possible value for
o4. For I, C, F, R centered
lattices,
o4 can also take the values:
I: 111
C: 110
F: 110, 101, 011
R: 211, 122
corresponding to the numerators of the inner node coordinates,
(1/2 1/2 1/2) for
I lattices, (1/2 1/2 0) for
C
lattices, (0 1/2 1/2) (1/2 0 1/2) (1/2 1/2 0) for
F
lattices and (1/3 2/3 2/3) (2/3 1/3 1/3) for
R lattices.
Example: <cell ... o4="000"/> (default)
Allowed values: 000, 111, 110
101, 011, 211, 122 (optional)
origin_vectors
Defines the type of cell vectors,
conventional or
primitive,
used to determine the node with
o1,
o2,
o3 coordinates,
as described above. When
o4 is not
000, a centered cell is
involved, so
origin_vectors must be
conventional.
When the lattice is primitive or vectors are primitive,
this corner node becomes the new origin node (000) and no more
coordinates are needed.
Example: <cell ... origin_vectors="conventional"/> (default)
(defined in GAMGI_PHYS_CELL_VECTORS_ORIGIN)
Allowed values: conventional, primitive (optional)
axes
Controls whether cell axes are visible. Axes are positioned at node (000),
and can be represented either by conventional or by primitive vectors.
The three axes use the rgb color scheme: red for the first axis, green
for the second and blue for the third.
Example: <cell ... axes="no"/> (default)
Allowed values: yes, no (optional)
axes_vectors
Defines the type of cell vectors,
conventional
or
primitive, that should be represented.
Example: <cell ... axes_vectors="conventional"/> (default)
(defined in GAMGI_PHYS_CELL_VECTORS_AXES)
Allowed values: conventional, primitive (optional)