ref: 2aa727ff0909f0c1a4be6bde77e3589d024e079b
dir: /sys/games/lib/life/billiard4/
........xx... ........x.... .........x... ........xx... .....xx...xx. ....x..xxx..x ....x.....xx. .....x...x... xx.x.x...x... x.xx.x.xx.... ....x.x...... ....x.x...... .....x.......