first commit

1 files changed, 480 insertions, 0 deletions

diff --git a/source.asm b/source.asm
new file mode 100644
index 0000000..0612e56
--- /dev/null
+++ b/source.asm
@@ -0,0 +1,480 @@
+covered_color equ 0x70
+controls_color equ 0x0f
+flag_character equ 'F' 
+bombs_per_65535 equ 5000
+
+board_width equ 26
+board_height equ 7
+offset_x equ 1
+offset_y equ 1
+
+org 0x0100
+
+  mov ax, 0x0501
+  int 0x10
+
+  xor ah, ah
+  int 0x1a
+
+  test dx, dx
+  jnz nonzero
+  inc dx
+nonzero:
+  mov word [xorshift_state], dx
+
+  mov cx, board_width * board_height
+  mov si, cx
+  mov di, board_flags
+bomb_loop:
+  call xorshift
+  cmp ax, bombs_per_65535
+  ja .no_bomb
+  mov byte [di], board_bomb
+  dec si
+.no_bomb:
+  inc di
+  loop bomb_loop
+  mov word [non_bombs_left], si
+
+  xor bx, bx
+  mov di, board_numbers
+number_loop:
+  call get_number_of_bx
+  mov byte [di], al
+  inc di
+  inc bl
+  cmp bl, board_width
+  jne number_loop
+  xor bl, bl
+  inc bh
+  cmp bh, board_height
+  jne number_loop
+
+  push 0xb900
+  pop es
+
+  xor di, di
+  mov ax, ' '
+  mov cx, 80 * 25
+  rep stosw
+
+  mov di, offset_y * 80 * 2 + offset_x * 2
+  mov ax, (covered_color << 8) | ' '
+gray_loop:
+  mov cx, board_width * 3
+  rep stosw
+  add di, (80 - board_width * 3) * 2
+  cmp di, (offset_y + board_height * 3) * 80 * 2 + offset_x * 2
+  jne gray_loop
+
+  mov si, controls_str
+  mov di, (offset_y + board_height * 3 + 1) * 80 * 2 + offset_x * 2 + ((board_width * 3 - controls_str.len) / 4) * 2
+  mov cx, controls_str.len
+  mov ah, controls_color
+show_controls_loop:
+  mov al, byte [si]
+  mov word [es:di], ax
+  inc si
+  add di, 2
+  loop show_controls_loop
+
+  call set_cursor
+
+main_loop:
+  xor ah, ah
+  int 0x16
+
+  cmp ah, 0x48
+  je up_arrow
+
+  cmp ah, 0x50
+  je down_arrow
+
+  cmp ah, 0x4b
+  je left_arrow
+
+  cmp ah, 0x4d
+  je right_arrow
+
+  cmp ah, 0x20
+  je dig
+
+  cmp ah, 0x21
+  je flag
+
+  cmp ah, 0x10
+  jne main_loop
+
+  mov ax, 0x0500
+  int 0x10
+
+  mov ax, 0x4c00
+  int 0x21
+
+xorshift_state:
+  dw 0
+
+xorshift:
+  mov ax, word [xorshift_state]
+  mov dx, ax
+  shl dx, 7
+  xor ax, dx
+  mov dx, ax
+  shr dx, 9
+  xor ax, dx
+  xor ah, al
+  mov word [xorshift_state], ax
+  ret
+
+;bx - y:x
+;preserves bx, di, and si
+;returns in ax
+bx_has_bomb:
+  push bx
+  movzx ax, bh
+  mov cx, board_width
+  mul cx
+  xor bh, bh
+  add bx, ax
+  mov ax, 0x1
+  and al, byte [board_flags + bx]
+  pop bx
+  ret
+
+;bx - y:x
+;preserves bx and di
+;returns in al
+get_number_of_bx:
+  xor si, si
+
+  test bh, bh
+  jz .no_ups
+
+  dec bh
+
+  test bl, bl
+  jz .no_ul
+
+  dec bl
+  call bx_has_bomb
+  add si, ax
+  inc bl
+
+.no_ul:
+  call bx_has_bomb
+  add si, ax
+
+  cmp bl, board_width - 1
+  je .no_ur
+
+  inc bl
+  call bx_has_bomb
+  add si, ax
+  dec bl
+
+.no_ur:
+  inc bh
+
+.no_ups:
+  test bl, bl
+  jz .no_cl
+
+  dec bl
+  call bx_has_bomb
+  add si, ax
+  inc bl
+
+.no_cl:
+  cmp bl, board_width - 1
+  je .no_cr
+
+  inc bl
+  call bx_has_bomb
+  add si, ax
+  dec bl
+
+.no_cr:
+  cmp bh, board_height - 1
+  je .no_downs
+
+  inc bh
+
+  test bl, bl
+  jz .no_bl
+
+  dec bl
+  call bx_has_bomb
+  add si, ax
+  inc bl
+
+.no_bl:
+  call bx_has_bomb
+  add si, ax
+
+  cmp bl, board_width - 1
+  je .no_br
+
+  inc bl
+  call bx_has_bomb
+  add si, ax
+  dec bl
+
+.no_br:
+  dec bh
+
+.no_downs:
+  mov ax, si
+  ret
+
+set_cursor:
+  mov ah, 0x02
+  mov bh, 0x01
+  mov cx, word [cursor_x]
+  mov dl, cl
+  add dl, cl
+  add dl, cl
+  add dl, offset_x + 1
+  mov dh, ch
+  add dh, ch
+  add dh, ch
+  add dh, offset_y + 1
+  int 0x10
+  jmp main_loop
+
+up_arrow:
+  mov al, byte [cursor_y]
+  test al, al
+  jz main_loop
+
+  dec al
+  mov byte [cursor_y], al
+  call set_cursor
+  jmp main_loop
+
+down_arrow:
+  mov al, byte [cursor_y]
+  cmp al, board_height - 1
+  je main_loop
+
+  inc al
+  mov byte [cursor_y], al
+  call set_cursor
+  jmp main_loop
+
+left_arrow:
+  mov al, byte [cursor_x]
+  test al, al
+  jz main_loop
+
+  dec al
+  mov byte [cursor_x], al
+  call set_cursor
+  jmp main_loop
+
+right_arrow:
+  mov al, byte [cursor_x]
+  cmp al, board_width - 1
+  je main_loop
+
+  inc al
+  mov byte [cursor_x], al
+  call set_cursor
+  jmp main_loop
+
+dig:
+  call get_board_flags_at_cursor
+  test al, board_uncovered | board_flagged
+  jnz main_loop
+
+  test al, board_bomb
+  jnz lose
+
+  or al, board_uncovered
+  call set_board_flags_at_cursor
+
+  push ax
+  call get_cursor_vram_offset
+  mov di, ax
+  pop ax
+
+  call get_number_at_cursor
+  movzx bx, al
+  mov al, byte [bx + uncovered_numbers]
+  mov ah, byte [bx + uncovered_colors]
+  mov word [es:di], ax
+
+  mov byte [es:di - 80 * 2 - 2 + 1], ah
+  mov byte [es:di - 80 * 2 + 1], ah
+  mov byte [es:di - 80 * 2 + 2 + 1], ah
+  mov byte [es:di - 2 + 1], ah
+  mov byte [es:di + 1], ah
+  mov byte [es:di + 2 + 1], ah
+  mov byte [es:di + 80 * 2 - 2 + 1], ah
+  mov byte [es:di + 80 * 2 + 1], ah
+  mov byte [es:di + 80 * 2 + 2 + 1], ah
+
+  mov ax, word [non_bombs_left]
+  dec ax
+
+  test ax, ax
+  jz win
+
+  mov word [non_bombs_left], ax
+
+  jmp main_loop
+
+uncovered_colors:
+  db 0x08, 0x08, 0x0a, 0x0c, 0x0b, 0x0e, 0x09, 0x07, 0x0f
+uncovered_numbers:
+  db " 12345678"
+
+flag:
+  call get_board_flags_at_cursor
+  test al, board_uncovered
+  jnz main_loop
+  xor al, board_flagged
+  push ax
+  call get_cursor_vram_offset
+  mov di, ax
+  pop ax
+  call set_board_flags_at_cursor
+
+  test al, board_flagged
+  jz .not_flagged
+
+  mov byte [es:di], flag_character
+  jmp main_loop
+
+.not_flagged:
+  mov byte [es:di], ' '
+  jmp main_loop
+
+;as rows
+board_flags:
+  times board_width * board_height db 0
+board_bomb equ 1
+board_uncovered equ 2
+board_flagged equ 4
+
+board_numbers:
+  times board_width * board_height db 0
+
+get_board_flags_at_cursor:
+  movzx ax, byte [cursor_y]
+  mov cx, board_width
+  mul cx
+  movzx bx, byte [cursor_x]
+  add bx, ax
+  mov al, byte [board_flags + bx]
+  ret
+
+get_cursor_vram_offset:
+  mov cx, word [cursor_x]
+
+  mov bl, cl
+  add bl, cl
+  add bl, cl
+  add bl, offset_x + 1
+
+  mov bh, ch
+  add bh, ch
+  add bh, ch
+  add bh, offset_y + 1
+
+  mov cx, 80
+  movzx ax, bh
+  mul cx
+  xor bh, bh
+  add ax, bx
+  add ax, ax
+
+  ret
+
+;preserves ax and di
+set_board_flags_at_cursor:
+  mov si, ax
+  movzx ax, byte [cursor_y]
+  mov cx, board_width
+  mul cx
+  movzx bx, byte [cursor_x]
+  add bx, ax
+  mov ax, si
+  mov byte [board_flags + bx], al
+  ret
+
+;preserves di
+get_number_at_cursor:
+  movzx ax, byte [cursor_y]
+  mov cx, board_width
+  mul cx
+  movzx bx, byte [cursor_x]
+  add bx, ax
+  mov al, byte [board_numbers + bx]
+  ret
+
+cursor_x:
+  db 0
+cursor_y:
+  db 0
+
+non_bombs_left:
+  dw 0
+
+controls_str:
+  db "Controls:   Arrows - Move Cursor   D - Dig   F - Flag   Q - Quit"
+.len equ $ - controls_str
+
+win:
+  push ds
+  pop es
+
+  mov ax, 0x1300
+  mov bx, 0x010f
+  mov cx, .len
+  mov dx, 0x0a24
+  mov bp, .str
+  int 0x10
+
+  jmp win_or_lose
+
+.str:
+  db "You win!"
+.len equ $ - .str
+
+lose:
+  push ds
+  pop es
+
+  mov ax, 0x1300
+  mov bx, 0x010f
+  mov cx, .len
+  mov dx, 0x0a23
+  mov bp, .str
+  int 0x10
+
+  jmp win_or_lose
+
+.str:
+  db "You lose!"
+.len equ $ - .str
+
+win_or_lose:
+  mov ax, 0x1300
+  mov bx, 0x010f
+  mov cx, .len
+  mov dx, 0x0c1d
+  mov bp, .str
+  int 0x10
+
+  xor ax, ax
+  int 0x16
+
+  mov ax, 0x0500
+  int 0x10
+
+  mov ax, 0x4c00
+  int 0x21
+
+.str:
+  db "Press any key to quit."
+.len equ $ - .str