diff options
Diffstat (limited to 'shell/life.mu')
| -rw-r--r-- | shell/life.mu | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/shell/life.mu b/shell/life.mu new file mode 100644 index 00000000..e4a2dbf7 --- /dev/null +++ b/shell/life.mu @@ -0,0 +1,245 @@ +fn state _grid: (addr array boolean), x: int, y: int -> _/eax: boolean { + # clip at the edge + compare x, 0 + { + break-if->= + return 0/false + } + compare y, 0 + { + break-if->= + return 0/false + } + compare x, 0x100/width + { + break-if-< + return 0/false + } + compare y, 0xc0/height + { + break-if-< + return 0/false + } + var idx/eax: int <- copy y + idx <- shift-left 8/log2width + idx <- add x + var grid/esi: (addr array boolean) <- copy _grid + var result/eax: (addr boolean) <- index grid, idx + return *result +} + +fn set-state _grid: (addr array boolean), x: int, y: int, val: boolean { + # don't bother checking bounds + var idx/eax: int <- copy y + idx <- shift-left 8/log2width + idx <- add x + var grid/esi: (addr array boolean) <- copy _grid + var result/eax: (addr boolean) <- index grid, idx + var src/ecx: boolean <- copy val + copy-to *result, src +} + +fn num-live-neighbors grid: (addr array boolean), x: int, y: int -> _/eax: int { + var result/edi: int <- copy 0 + # row above: zig + decrement y + decrement x + var s/eax: boolean <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + increment x + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + increment x + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + # curr row: zag + increment y + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + subtract-from x, 2 + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + # row below: zig + increment y + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + increment x + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + increment x + s <- state grid, x, y + { + compare s, 0/false + break-if-= + result <- increment + } + return result +} + +fn step old-grid: (addr array boolean), new-grid: (addr array boolean) { + var y/ecx: int <- copy 0 + { + compare y, 0xc0/height + break-if->= + var x/edx: int <- copy 0 + { + compare x, 0x100/width + break-if->= + var n/eax: int <- num-live-neighbors old-grid, x, y + # if neighbors < 2, die of loneliness + { + compare n, 2 + break-if->= + set-state new-grid, x, y, 0/dead + } + # if neighbors > 3, die of overcrowding + { + compare n, 3 + break-if-<= + set-state new-grid, x, y, 0/dead + } + # if neighbors = 2, preserve state + { + compare n, 2 + break-if-!= + var old-state/eax: boolean <- state old-grid, x, y + set-state new-grid, x, y, old-state + } + # if neighbors = 3, cell quickens to life + { + compare n, 3 + break-if-!= + set-state new-grid, x, y, 1/live + } + x <- increment + loop + } + y <- increment + loop + } +} + +# color a square of size 'side' starting at x*side, y*side +fn render-square _x: int, _y: int, color: int { + var y/edx: int <- copy _y + y <- shift-left 2/log2side + var side/ebx: int <- copy 1 + side <- shift-left 2/log2side + var ymax/ecx: int <- copy y + ymax <- add side + { + compare y, ymax + break-if->= + { + var x/eax: int <- copy _x + x <- shift-left 2/log2side + var xmax/ecx: int <- copy x + xmax <- add side + { + compare x, xmax + break-if->= + pixel-on-real-screen x, y, color + x <- increment + loop + } + } + y <- increment + loop + } +} + +fn render grid: (addr array boolean) { + var y/ecx: int <- copy 0 + { + compare y, 0xc0/height + break-if->= + var x/edx: int <- copy 0 + { + compare x, 0x100/width + break-if->= + var state/eax: boolean <- state grid, x, y + compare state, 0/false + { + break-if-= + render-square x, y, 3/cyan + } + compare state, 0/false + { + break-if-!= + render-square x, y, 0/black + } + x <- increment + loop + } + y <- increment + loop + } +} + +fn life { +#? # allocate on the stack +#? var grid1-storage: (array boolean 0xc000) # width * height +#? var grid1/esi: (addr array boolean) <- address grid1-storage +#? var grid2-storage: (array boolean 0xc000) # width * height +#? var grid2/edi: (addr array boolean) <- address grid2-storage + # allocate on the heap + var grid1-storage: (handle array boolean) + var grid1-ah/eax: (addr handle array boolean) <- address grid1-storage + populate grid1-ah, 0xc000 # width * height + var _grid1/eax: (addr array boolean) <- lookup *grid1-ah + var grid1/esi: (addr array boolean) <- copy _grid1 + var grid2-storage: (handle array boolean) + var grid2-ah/eax: (addr handle array boolean) <- address grid2-storage + populate grid2-ah, 0xc000 # width * height + var _grid2/eax: (addr array boolean) <- lookup *grid2-ah + var grid2/edi: (addr array boolean) <- copy _grid2 + # initialize grid1 + set-state grid1, 0x80, 0x5f, 1/live + set-state grid1, 0x81, 0x5f, 1/live + set-state grid1, 0x7f, 0x60, 1/live + set-state grid1, 0x80, 0x60, 1/live + set-state grid1, 0x80, 0x61, 1/live + # render grid1 + render grid1 + { + var key/eax: byte <- read-key 0/keyboard + compare key, 0 +#? loop-if-= # press key to step + break-if-!= # press key to quit # comment this out to run under bochs; I'm not sure why there's a newline in the keyboard buffer + # iter: grid1 -> grid2 + step grid1, grid2 + render grid2 + # iter: grid2 -> grid1 + step grid2, grid1 + render grid1 + loop + } +} |