Barrister

Usage

To build, run git submodule update --init to fetch the TOML library, and then run make.

./Barrister inputs/test.toml

Input Parameters

See inputs/snark.toml etc.

The pattern parameter must be a LifeHistory RLE, where the states have the following meaning:

• state 1 (green): active pattern
• state 2 (blue): unknown cells where the catalyst to-be-found may lie
• state 3 (pale green): cells that must be ON cells of the catalyst, initially ON
• state 4 (red): cells that must be ON cells of the catalyst, initially OFF
• state 5 (yellow): "stator" ON cells that must not be disturbed, for unrelated catalysts
• state 6 (grey): unused

Generally, constraints are only applied to cells in the ZOI of the catalyst. In each generation, the "active" cells are those that are not equal to the stable state and "changed" cells are those that are not equal to the state in the previous generation. "Ever-active" cells are those that are active in at least one generation.

For values of max-cell-active-window and max-cell-active-streak other than 0, you will have to edit the corresponding variable at the top of Barrister.cpp and recompile. (These constraints can use much more memory.)

Parameter	Format	Description
pattern	'''multiline rle'''	Pattern to search, as described above
pattern-center	[x, y]	Coordinate in the RLE to be placed at the origin
first-active-range	[start, end]	Range of generations in which the interaction must start
active-window-range	[min, max]	Range of interaction durations that are allowed
min-stable-interval	n	Duration the catalyst must stay stable after interaction to be accepted
max-active-cells	n	Maximum count of active cells in any generation
max-ever-active-cells	n	Maximum count of ever-active cells
max-changes	n	Maximum count of changed cells in any generation
active-bounds	[width, height]	Maximum bounds the active cells in any generation
ever-active-bounds	[width, height]	Maximum bounds of the ever-active cells
changes-bounds	[width, height]	Maximum bounds the changed cells in any generation
max-component-active-cells	n	Versions of the above that separate the relevant cells into components before applying the constraints
max-component-ever-active	n
max-component-changes	n
component-active-bounds	[width, height]
component-ever-active-bounds	[width, height]
component-changes-bounds	[width, height]
max-cell-active-window	n	Maximum time a cell may remain active after being active the first time
max-cell-active-streak	n	Maximum time a cell may remain active in a row
max-cell-stationary-distance	n	The maximum distance that an active, unchanging cell may be changing cells
exempt-existing	true or false	Exempt the parts of the catalyst supplied in the input from the constraints (default true)
print-summary	true or false	Print all solutions as a single pattern at the end of the search (default true)
stabilise-results	true or false	Stabilise each result into a complete still life (default true)
minimise-results	true or false	Try and find the minimal completion or report the first found (default false)
stabilise-results-timeout	secs	How long to spend trying to find a minimal completion (default 3)
trim-results	true or false	Try and collect catalysts that cause different perturbations (default true)
report-oscillators	true or false	Only report oscillators (with period > 4) (default false)
report-oscillators-min-period	true or false	Minimum period worthy of reporting (default 5)

Filters and Forbiddens

Each block headed by [[filter]] represents a filter that must be matched for the solution to be reported. The pattern to be matched must be provided as a LifeHistory RLE, using states 3 and 4. See inputs/snark.toml for an example. There may be many filters.

Filters of type EXACT are passed when the reaction matches the filter on the generation filter-gen. Filters of type EVER are passed when the reaction matches the filter at some point before filter-gen, and after the start of the interaction with the catalyst.

Parameter	Format	Description
filter	'''multiline rle'''
filter-type	"EXACT" or "EVER"	(default "EVER")
filter-gen	n
filter-pos	[x, y]

Each block headed by [[forbidden]] represents a piece of stable catalyst that may not occur in the solution. The pattern to be matched must be provided as a LifeHistory RLE, using states 3 and 4. See inputs/elbow.toml for an example.

Parameter	Format	Description
forbidden	'''multiline rle'''
forbidden-pos	[x, y]

Metasearches

Parameter	Format	Description
metasearch	true or false	(default false)
metasearch-rounds
meta-first-active-range

TODO