life.xtl

1⍝# Conway's Life in a native window: the board is an X_eTaL array, each
2⍝# generation one array expression, drawn by Rust with every frame.
3⍝# Run: just demo canvas life   (Space: a new board; q or close: quit)
4
5ᶜᵛ⁼u̲se< "Canvas"
6
7⍝# Life (as in X_eTaL's demos/life.xtl): every cell plus its neighbors
8⍝# by rotating along both axes and summing; alive next at 3, or 4 if alive
9ᵘl̲ife ← { ('+ r̲/₁₂ -1 0 1 o̲-₁₂ ⍵) { (⍺ = 3) + ⍵ × ⍺ = 4 } ⍵ }
10
11⍝# a random board, about one cell in four alive
12ᵘs̲eed ← { n → (n c̲at n) r̲eshape 1 = r̲oll! (n × n) r̲eshape 4 }
13
14w ← "Life -- X_eTaL" ᶜᵛo̲pen! 512 512
15
16⍝# after quitting: close the window; an empty board ends the loop's work
17ᵘq̲uit ← { b →
18  c ← ᶜᵛc̲lose! w
19  0 0 r̲eshape 0
20}
21
22⍝# one frame: draw the board, read an event, step
23ᵘf̲rame ← { b →
24  0 = t̲ally b ? b
25  e ← ᶜᵛn̲ext! w
26  ((e m̲atch "close") + e m̲atch "key q") > 0 ? ᵘq̲uit b
27  e m̲atch "key Space" ? ᵘs̲eed 96
28  s ← w ᶜᵛs̲how! b
29  ᵘl̲ife b
30}
31
32⍝# up to 100,000 frames (about half an hour at 60 a second)
33last ← 100000 'ᵘf̲rame p̲ower ᵘs̲eed 96
34"bye"