gol (Game of Life)

gol is a Game of Life library for C++.

With gol, you can easily simulate Conway's Game of Life cellular automaton in C++. gol is a single-file include which means you only need one header file to use it.

Features

• A board class to iterate through and store a Conway's Game of Life simulation
• Custom rule strings, wrapping, and neighborhood types
• File parsing and saving (including support for run-length encoding)
• Documentation

Installation

1. Download the latest single header version.
2. Either put the header file in a central location (with a specified path) or directly in your project tree.

Examples

To compile all the examples:

$ make example-compile

Blinker Oscillator

Here is an implementation that prints a blinker oscillator and steps 4 times:

// Implements a blinker oscillator and steps 4 times
// blinker oscillators have a period of 2 

#include <gol/gol.hpp>

#include <iostream>

gol::Board board(10, 10);

// Prints the board and then updates with next step
void printAndStep() {
    std::cout << "\n";
    for(int i = 0; i < board.height(); i++) {
        for(int j = 0; j < board.width(); j++) {
            std::cout << board[i][j] << " ";
        }
        std::cout << "\n";
    }
    board.nextStep(); // Update with next step with rule_string B3/S23
}

int main() {
    for(int i = 0; i < board.height(); i++) {
        for(int j = 0; j < board.width(); j++) {
            board[i][j] = false;
        }
    }

    // Make blinker oscillator
    board[2][2] = true;
    board[2][3] = true;
    board[2][4] = true;

    for(int i = 0; i < 4; i++) {
        printAndStep();
    }
}

This will print the following twice:

0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 
0 0 1 1 1 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 

0 0 0 0 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0
0 0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 

Preview

Previewing requires SDL2.

Refer to the /preview directory to see how gol can be used with SDL2 to preview simulations graphically.

Compile the previewer with:

$ make preview-compile

Run the previewer with:

$ make preview

Testing

Testing requires Catch2.

Compile with:

$ make test-compile

Run the tests with:

$ make test

Reference

Documentation

Functions

Function	Use
initRandom	Initialize random seed
getRandomBool	Return a random bool
getBirthValues	Return birth values from B/S notation rule string
getSurvivalValues	Return survival values from B/S notation rule string
isValidRuleString	Test whether rule string is valid

Board Member Functions

Function	Use
(constructor)	Construct Game of Life board
operator[]	Access element
height	Return the number of rows
width	Return the number of columns
countNeighborsMoore	Return number of true cells in Moore neighborhood
countNeighborsNeumann	Return number of true cells in von Neumann neighborhood
nextStep	Iterate to next time step
setWrap	Set to toggle wrapping for counting neighbors
getWrap	Return the current wrap state
getNeighborhoodType	Return current neighborhood type
setFromFile	Set values of board from given file
getLiveCount	Return the number of true elements
getDeadCount	Return the number of false elements
setFromRLEFile	Set values of board from given RLE file
setRuleString	Set rule string
getRuleString	Return current rule string
saveAsFile	Save board as file
saveAsRLEFile	Save board as RLE file