Life in Apple BASIC

LIFE

100 size = 10
101 gfx = 5
102 gr
103 color = gfx
200 dim board(size, size)
210 dim temp(size, size)

300 gosub 800 : rem random
310 rem main loop
320 gosub 900 : rem render
330 gosub 600 : rem do rules
340 goto 320

600 rem run rules
605 print "simulating..."
610 for y=0 to size : for x=0 to size
615 live = 0
620 if x - 1 >= 0 then : if board(x - 1, y) = 1 then live = live + 1 : rem left
625 if x + 1 <= size then : if board(x + 1, y) = 1 then live = live + 1 : rem right
630 if y - 1 >= 0 then : if board(x, y - 1) = 1 then live = live + 1 : rem top
635 if y + 1 <= size then : if board(x, y + 1) = 1 then live = live + 1 : rem bottom
640 if x - 1 >= 0 and y - 1 >= 0 then : if board(x - 1, y - 1) = 1 then live = live + 1 : rem top left
645 if x + 1 <= size and y - 1 >= 0 then : if board(x + 1, y - 1) = 1 then live = live + 1 : rem top right
650 if x - 1 >= 0 and y + 1 <= size then : if board(x - 1, y + 1) = 1 then live = live + 1 : rem bottom left
655 if x + 1 <= size and y + 1 <= size then : if board(x + 1, y + 1) = 1 then live = live + 1 : rem bottom right

660 if board(x,y) = 1 and live < 2 then temp(x,y) = 0 : goto 690
665 if board(x,y) = 1 and live > 3 then temp(x,y) = 0 : goto 690
670 if board(x,y) = 1 and live = 2 then temp(x,y) = 1 : goto 690
675 if board(x,y) = 1 and live = 3 then temp(x,y) = 1 : goto 690
680 if board(x,y) = 0 and live = 3 then temp(x,y) = 1 : goto 690
685 if board(x,y) = 0 and live >< 3 then temp(x,y) = 0 : goto 690
690 next x : next y
695 print "moving data..."
700 for y=1 to size : for x=1 to size : board(x,y) = temp(x,y) : next x : next y
710 return

800 rem randomize board
810 print "randomizing..."
820 for y=0 to size : for x=0 to size
830 board(x, y) = int(rnd(1)*2)
840 next x : next y
850 return

400 rem glider spawn
405 board(2,1) = 1
410 board(3,2) = 1
415 board(1,3) = 1
420 board(2,3) = 1
425 board(3,3) = 1
430 return

900 rem render screen
910 print "drawing..."
920 for y=0 to size : for x=0 to size
930 color = 1 : if board(x,y) = 1 then color = gfx
940 plot x, y
950 next x : next y
999 return

This is really slow, and does not handle the edges of the board correctly, but it otherwise works correctly.