EXTRA: lat_grid - lattices and grids with integer coordinates
Usage: lat_grid [options] [lat_type [outer_width [inner_width]]]
Make a lattice or grid with integer coordinates. Lattice types (default: sc)
are followed by name and then and valid strut arguments (squares of length,
first is square of the radius of balls packed at the vertex positions)
sc - Simple Cubic (1, 2, 3)
fcc - Face Centred Cubic (2, 4, 6, 12)
bcc - Body Centred Cubic (3, 4, 8)
hcp - Hexagonal Close Packing (18)
rh_dodec - Rhombic Dodecahedra (3, 8) cubo_oct - Cuboctahedron / Octahedron (2)
tr_oct - Truncated Octahedron (2)
tr_tet_tet - Truncated Tetrahedron / Tetrahedron (2)
tr_tet_tr_oct_cubo - Truncated Tetrahedron /
Truncated Octahedron / Cuboctahedron (4)
diamond - Diamond (3)
hcp_diamond - HCP Diamond (27)
k_4 - K_4 Crystal (2)
Inner and outer widths are the sizes of the inner and outer containers.
For cubes, these are the length of a side, for spheres these are the
squares of the radii.
Options
-h,--help this help message (run 'off_util -H help' for general help)
--version version information
-C <cent> centre of lattice, in form \"x_val,y_val,z_val\"
-c <type> container, c - cube (default), s - sphere
-s <len2> create struts, the value is the square of the strut length
-o <file> write output to file (default: write to standard output)
View a cubic section of Close Cubic Packing
lat_grid fcc 6 | antiview -v b
Make a spherical section of a diamond grid
lat_grid -c s -s 3 diamond 16 | antiview
Spherical container suggested by
Steve Waterman,
who has made a collection of
hulls of spherically contained lattices.
The grids of shortest strut length represent the edges of a
packing of polyhedra, with the exception of diamond, HCP diamond
and K_4.
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EXTRA: string_art - string figures
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