Procedural Generation in Ruby

A lightning talk I did at VanRuby in December 2016. I talked about video games and pseudo-random number generators!

Transcript

1. Procedural Generation in Ruby
2. Alex Taylor @mctaylorpants
3. Alex Taylor @mctaylorpants
4. Alex Taylor @mctaylorpants 566034820233894 = Images from noelberry.ca
5. Alex Taylor @mctaylorpants rand
6. Alex Taylor @mctaylorpants def generate_world(seed = 123) end
7. Alex Taylor @mctaylorpants
8. Alex Taylor @mctaylorpants
9. Alex Taylor @mctaylorpants rand != ‘truly random’
10. Alex Taylor @mctaylorpants PRNG • Pseudo-random number generator • Appears random... • ...but actually deterministic rspec --seed 123
11. Alex Taylor @mctaylorpants srand • Initializes Ruby’s PRNG • Per-process
12. Alex Taylor @mctaylorpants a = [1, 2, 3, 4, 5] srand(123) a.sample => 3 a.sample => 5 a.sample => 3 a.shuffle => [1, 5, 3, 4, 2] rand => 0.7800277619120791
13. Alex Taylor @mctaylorpants
14. Alex Taylor @mctaylorpants a = [1, 2, 3, 4, 5] srand(123) a.sample => 3 a.sample => 5 a.sample => 3 a.shuffle => [1, 5, 3, 4, 2] rand => 0.7800277619120791
15. Alex Taylor @mctaylorpants 123
16. Alex Taylor @mctaylorpants LOVE ME
17. Alex Taylor @mctaylorpants srand(123) a = ['n', 't', 'k', 'h', 'a', 's'] a.shuffle.join => “thanks”