12 releases

0.6.1 Mar 18, 2023
0.6.0 May 1, 2022
0.5.2 Jan 1, 2022
0.5.1 Jul 17, 2021
0.3.1 Jan 4, 2020

#115 in Game dev

39 downloads per month

MIT license

4.5K SLoC


GitHub Workflow Status Crates.io 中文

Rust Life Search, or rlifesrc, is a Game of Life pattern searcher written in Rust.

The program is based on David Bell's lifesrc and Jason Summers's WinLifeSearch, using an algorithm invented by Dean Hickerson.

Compared to WinLifeSearch, rlifesrc is still slower, and lacks many important features. But it supports non-totalistic Life-like and Generations rules.

This is the command-line tool and the TUI. There is also a web app using WebAssembly.


rlifesrc is written in Rust. You can install it with Rust's package manager, Cargo:

cargo install rlifesrc

If you want to compile from the source code, please see the Compiling part.


This algorithm is suitable for long and thin or flat and wide patterns, but it can also search for other patterns.

It provides two interfaces: a simple command line interface and a text-based user interface.

    rlifesrc [FLAGS] [OPTIONS] <X> <Y> [ARGS]

    -a, --all
            Prints all possible results instead of only the first one
            Only useful when --no-tui is set.

            (Experimental) Enable backjumping
            The current implementation of backjumping is very slow, only useful for large (e.g., 64x64) still lifes.

    -n, --no-tui
            Starts searching immediately, without entering the TUI

    -R, --reduce
            Reduce the max cell count when a result is found
            The new max cell count will be set to the cell count of the current result minus one.

            Resets the time when starting a new search

    -S, --skip-subsym
            Skip patterns which are invariant under more transformations than required by the given symmetry.
            In another word, skip patterns whose symmetry group properly contains the given symmetry group.

    -p, --subperiod
            Allow patterns whose fundamental period are smaller than the given period

    -h, --help
            Prints help information

    -V, --version
            Prints version information

    -c, --choose <CHOOSE>
            How to choose a state for unknown cells
             [default: alive]  [possible values: dead, alive, random, d, a, r]

    -C, --config <CONFIG>
            Read config from a file
            Supported formats: JSON, YAML, TOML.
            When a config file is provided, all the other flags and options, except --all (-a), --reset-time, --no-tui (-n), are ignored.

    -d, --diag <DIAG>
            Diagonal width
            If the diagonal width is n > 0, the cells at position (x, y) where abs(x - y) >= n are assumed to be dead.
            If this value is set to 0, it would be ignored.
             [default: 0]

    -m, --max <MAX>
            Upper bound of numbers of minimum living cells in all generations
            If this value is set to 0, it means there is no limitation.
             [default: 0]

    -o, --order <ORDER>
            Search order
            Row first or column first.
             [default: automatic]  [possible values: row, column, automatic, diagonal, r, c, a, d]

    -r, --rule <RULE>
            Rule of the cellular automaton
            Supports Life-like, isotropic non-totalistic, hexagonal, MAP rules, and their corresponding Generations rules.
             [default: B3/S23]

    -s, --symmetry <SYMMETRY>
            Symmetry of the pattern
            You may need to add quotation marks for some of the symmetries.
            The usages of these symmetries are the same as Oscar Cunningham's Logic Life Search.
            See [https://conwaylife.com/wiki/Static_symmetry#Reflectional]
             [default: C1]  [possible values: C1, C2, C4, D2|, D2-, D2\, D2/, D4+, D4X, D8]

    -t, --transform <TRANSFORM>
            Transformation of the pattern
            After the last generation in a period, the pattern will return to the first generation, applying this transformation first, and then the translation defined by DX and DY.
            You may need to add quotation marks for some of the transformations.
            "Id" is the identical transformation.
            "R" means counterclockwise rotation.
            "F" means flipping (reflection) across an axis.
             [default: Id]  [possible values: Id, R90, R180, R270, F|, F-, F\, F/]

            Width of the pattern

            Height of the pattern

            Period of the pattern [default: 1]

            Horizontal translation [default: 0]

            Vertical translation [default: 0]

For example, this will find 25P3H1V0.1

rlifesrc 16 5 3 0 1

You can also read the config from a file:

rlifesrc -C config.json

Where the content of config.json is:

    "width": 16,
    "height": 5,
    "period": 3,
    "dx": 0,
    "dy": 1,

The config file is just a serialization of the Config struct of rlifesrc-lib. Currently, the known_cells field, and the FromVec variant of SearchOrder, can only be specified through the config file. Please see the documentation for Config for details.

10 different symmetries correspond to the 10 subgroups of the dihedral group _D_8. The notations are stolen from Oscar Cunningham's Logic Life Search. Please see the Life Wiki for details.

8 different transformations correspond to the 10 elements of the dihedral group _D_8. Here:

  • Id means the identity transformation.
  • R means rotations around the center of the world. The number after it is the counterclockwise rotation angle in degrees.
  • F means reflections (flips). The symbol after it is the axis of reflection.

For example, if you want to find a vertical spaceship with glide symmetric, you can set the transformation to F|.

Some of the symmetries and transformations are only valid when the world is square. Some are only valid when the world have no diagonal width.

“Automatic” in the search order means that it will start from the shorter side, i.e., start from the columns if there are more columns than rows, from the rows if there are more rows than columns. When the world is square and the diagonal width is not larger than width of the world, it would choose diagonal.

Diagonal search order requires that the world is square.


The command line interface (CLI) is the simplest interface. You input the commands, and it will print the result, without showing the search process.

The result is printed in a mix of Plaintext and RLE format. Specifically:

  • Dead cells are represented by .;
  • Living cells are represented by o for rules with 2 states, A for rules with more states;
  • Dying cells are represented by uppercase letters starting from B;
  • Unknown cells are represented by ?;
  • Each line is ended with $;
  • The whole pattern is ended with !.

Currently it cannot properly display Generations rules with more than 25 states.

For example, this input:

rlifesrc 20 16 7 3 0 -r '3457/357/5' -s 'D2-' --no-tui

will give:

x = 20, y = 16, rule = 3457/357/5

With the command line flag --all, it will print all the results one by one.


The text-based user interface (TUI) is also simple, but it will show the search progress and the search time.

The TUI is written with crossterm. Theoretically it should be cross platform, but I have only tested it on Xfce Terminal.

When you enter the TUI, it looks like this (taking rlifesrc 20 16 7 3 0 -r '3457/357/5' -s 'D2-' as an example):

The output format during the search is the same as that of the CLI, except that ? means unknown cells.

Cells means the number of known living cells in the current generation. For Generations rules, dying cells are not counted. Confl means the number of conflicts during the search.

Then you can control the search with the keyboard:

  • space / enter: start or pause the search
  • q: quit
  • page up: show the last generation
  • page down: show the next generation

The search result looks like this:

If you press space or enter again, it will start to search the next result.

The time is only shown when the search is paused. It will not be reset when starting a new search, unless the command line flag --reset-time is added.

rlifesrc is unable to display the whole pattern when it is larger than the terminal size. But the whole result will be printed after quitting the program.


rlifesrc is written in Rust. So first you need to install Rust.

And then you can download and compile:

git clone https://github.com/AlephAlpha/rlifesrc.git
cd rlifesrc/
RUSTFLAGS="-C target-cpu=native" cargo build --release

The output file is ./target/release/rlifesrc.

If you don't need the TUI, you can add the flag --no-default-features to cargo-build.


~196K SLoC