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+--- Thread: Knightbridge (/thread-380.html)
Knightbridge - johnno56 - 04-08-2026
Knightbridge is a simple board game between a player and the computer. Each player has a set of Chess Knights. Each player takes turn in moving one piece per turn. Each piece MUST move in the same manner as a Chess Knight. Two squares forward then one square left or right.
The object of the game is to "capture" your opponent by "landing" on it. The first player to capture Five pieces wins.
Run the game. Select the level of difficulty. Click on your Knight (it will then be highlighted) then click on the target square.
During the game, if you like, you can change the look of the board by pressing "A", "B", "C" or "D"
The original game was displayed using text only with a 7x7 board and a single row of Knights each.
N7knights.zip (Size: 353.84 KB / Downloads: 5)
RE: Knightbridge - Marcus - 04-08-2026
(04-08-2026, 04:51 AM)johnno56 Wrote: Knightbridge is a simple board game between a player and the computer. Each player has a set of Chess Knights. Each player takes turn in moving one piece per turn. Each piece MUST move in the same manner as a Chess Knight. Two squares forward then one square left or right.
The object of the game is to "capture" your opponent by "landing" on it. The first player to capture Five pieces wins.
Run the game. Select the level of difficulty. Click on your Knight (it will then be highlighted) then click on the target square.
During the game, if you like, you can change the look of the board by pressing "A", "B", "C" or "D"
The original game was displayed using text only with a 7x7 board and a single row of Knights each.
Ooh! Something to look forward to after work!
RE: Knightbridge - johnno56 - 04-08-2026
It could probably do with a a light coat of "serious optimisation" and better menu system.... But it seems to work.... Gotta love the classics... lol
RE: Knightbridge - Marcus - 04-08-2026
I WON!
... on easy.
Thanks for the game!
RE: Knightbridge - johnno56 - 04-08-2026
Play time is quite short... but, back in the early days (pre 1985), CPU's and memory were not like they are today. This was OH SO much slower back then... in text none the less!
This is how the original looked... I still have the listing... Line numbers and all... lol
RE: Knightbridge - 1micha.elok - 04-09-2026
Hi Johnno,
Thanks for sharing Knightbridge !
I honestly thought programming a knight's moves would take thousands of lines just to make the piece "think". Turns out it only takes a handful
... Anyway, since it's so lightweight now, what if we tried a fun 4x4 version just packed with twin knights ? .... lol
![[Image: bqwGY.gif]](https://s13.gifyu.com/images/bqwGY.gif)
Code:
' ==================
' KNIGHTSBRIDGE 4x4
' ==================
#win32
set window "Knightsbridge 4x4", 260, 260, false, 2
set redraw off
randomize clock()
' Constants
constant BOARD_SIZE = 4
constant SQUARE_SIZE = 60
constant BOARD_X = 10
constant BOARD_Y = 10
constant HUMAN = 1
constant AI_PLAYER = 2
' Load Assets
visible black = loadimage("assets/black2.png")
visible white = loadimage("assets/white2.png")
' Globals
visible board = dim(BOARD_SIZE, BOARD_SIZE) ' 0=empty, 1=human, 2=AI
visible captures = dim(3) ' captures[1]=human, captures[2]=AI
visible knight_dx = dim(8)
visible knight_dy = dim(8)
visible selected_r , selected_c
visible current_turn=HUMAN, game_over=false, winner
visible mx, my, click_handled
visible last_ai_fr = -1, last_ai_fc = -1
visible last_ai_tr = -1, last_ai_tc = -1
init_knight_moves()
init_board()
'-----------
' MAIN LOOP
'-----------
do
draw_board()
mx = mousex()
my = mousey()
if not game_over then
if mousebutton(0) = 1 and click_handled = 0 then
click_handled = 1
if mx >= BOARD_X and mx < BOARD_X + BOARD_SIZE * SQUARE_SIZE and
my >= BOARD_Y and my < BOARD_Y + BOARD_SIZE * SQUARE_SIZE then
col = int((mx - BOARD_X) / SQUARE_SIZE)
row = int((my - BOARD_Y) / SQUARE_SIZE)
if selected_r = -1 then
if board[row][col] = HUMAN then
selected_r = row
selected_c = col
endif
else
if is_valid_knight_move(selected_r, selected_c, row, col, HUMAN) then
do_move(selected_r, selected_c, row, col)
selected_r = -1
selected_c = -1
current_turn = AI_PLAYER
else
if board[row][col] = HUMAN then
selected_r = row
selected_c = col
else
selected_r = -1
selected_c = -1
endif
endif
endif
else
selected_r = -1
selected_c = -1
endif
endif
if mousebutton(0) = 0 then click_handled = 0
if current_turn = AI_PLAYER and game_over = false then
ai_make_move()
endif
else
if keydown(KEY_Y, false) then
init_board()
selected_r = -1; selected_c = -1
current_turn = HUMAN
game_over = false
winner = 0
last_ai_fr = -1 ;last_ai_tr = -1
last_ai_fc = -1 ;last_ai_tc = -1
click_handled = 0
endif
if keydown(KEY_N, false) then
end
endif
endif
redraw
fwait 60
loop
'------------
' FUNCTIONS
'------------
function init_knight_moves()
'8 possible L-shaped moves a knight can make
knight_dx[0] = 2 ; knight_dy[0] = 1 ' 2 squares right, 1 square down
knight_dx[1] = 2 ; knight_dy[1] = -1
knight_dx[2] = -2 ; knight_dy[2] = 1 ' 2 squares left, 1 square down
knight_dx[3] = -2 ; knight_dy[3] = -1
knight_dx[4] = 1 ; knight_dy[4] = 2
knight_dx[5] = 1 ; knight_dy[5] = -2 ' 1 square right, 2 squares up
knight_dx[6] = -1 ; knight_dy[6] = 2
knight_dx[7] = -1 ; knight_dy[7] = -2
endfunc
function init_board()
for r = 0 to BOARD_SIZE - 1
for c = 0 to BOARD_SIZE - 1
board[r][c] = 0
next
next
' AI knights (top two rows, staggered)
for c = 0 to BOARD_SIZE - 1 step 2
board[0][c] = AI_PLAYER
next
for c = 1 to BOARD_SIZE - 1 step 2
board[1][c] = AI_PLAYER
next
' Human knights (bottom two rows, staggered)
for c = 1 to BOARD_SIZE - 1 step 2
board[2][c] = HUMAN
next
for c = 0 to BOARD_SIZE - 1 step 2
board[3][c] = HUMAN
next
captures[1] = 0
captures[2] = 0
endfunc
function is_valid_knight_move(sr, sc, tr, tc, player)
dr = abs(tr - sr)
dc = abs(tc - sc)
'Verify Knight's L-Shape move
if (dr = 1 and dc = 2) or (dr = 2 and dc = 1) then
if tr >= 0 and tr < BOARD_SIZE and tc >= 0 and tc < BOARD_SIZE then
if board[tr][tc] = 0 or board[tr][tc] <> player then
return true
endif
endif
endif
return false
endfunc
function do_move(sr, sc, tr, tc)
'whose piece is moving, 1=human, 2=computer
mover = board[sr][sc]
'read what's currently on the destination square (tr,tc)
'0=empty, 1=human, 2=computer
captured = board[tr][tc]
'place the piece on destination
board[tr][tc] = mover
board[sr][sc] = 0
'check if a capture occured
if captured <> 0 then
captures[mover] = captures[mover] + 1
if captures[mover] >= 3 then 'victory condition
game_over = true
winner = mover
endif
endif
endfunc
function draw_board()
set color 0, 0, 0; cls
for r = 0 to BOARD_SIZE - 1
for c = 0 to BOARD_SIZE - 1
if (r + c) % 2 = 0 then
set color 200, 220, 200
else
set color 100, 140, 100
endif
draw rect BOARD_X + c * SQUARE_SIZE, BOARD_Y + r * SQUARE_SIZE,
SQUARE_SIZE, SQUARE_SIZE, true
next
next
for r = 0 to BOARD_SIZE - 1
for c = 0 to BOARD_SIZE - 1
if board[r][c] > 0 then
x = BOARD_X + c * SQUARE_SIZE + 5
y = BOARD_Y + r * SQUARE_SIZE
if board[r][c] = HUMAN then
draw image white, x, y
else
draw image black, x, y
endif
endif
next
next
' Highlight AI's last move FROM
if last_ai_fr >= 0 then
x = BOARD_X + last_ai_fc * SQUARE_SIZE
y = BOARD_Y + last_ai_fr * SQUARE_SIZE
set color 255, 0, 0
draw rect x, y, SQUARE_SIZE, SQUARE_SIZE, false
draw rect x+2, y+2, SQUARE_SIZE-4, SQUARE_SIZE-4, false
endif
' Highlight AI's last move TO
if last_ai_tr >= 0 then
x = BOARD_X + last_ai_tc * SQUARE_SIZE
y = BOARD_Y + last_ai_tr * SQUARE_SIZE
set color 255, 0, 0
draw rect x, y, SQUARE_SIZE, SQUARE_SIZE, false
draw rect x+2, y+2, SQUARE_SIZE-4, SQUARE_SIZE-4, false
endif
' Hightlight Human Knight
if selected_r >= 0 then
x = BOARD_X + selected_c * SQUARE_SIZE
y = BOARD_Y + selected_r * SQUARE_SIZE
set color 0, 255, 0
draw rect x, y, SQUARE_SIZE, SQUARE_SIZE, false
draw rect x+2, y+2, SQUARE_SIZE-4, SQUARE_SIZE-4, false
endif
if game_over then
set color 0, 0, 0
draw rect BOARD_X + 20, BOARD_Y + 50, 200, 110, true
set color 255, 255, 255
draw rect BOARD_X + 22, BOARD_Y + 52, 196, 106, false
if winner = HUMAN then
set color 0, 255, 0
set caret BOARD_X + 120, BOARD_Y + 80
center "YOU WIN!"
else
set color 255, 0, 0
set caret BOARD_X + 120, BOARD_Y + 80
center "AI WINS!"
endif
set color 255, 255, 255
set caret BOARD_X + 120, BOARD_Y + 105
center "Restart (Y/N)?"
endif
endfunc
function ai_make_move()
'Step 1 : Initialize fallback variables
' fr/fc = from row/column
' tr/tc = to row/column
fr = -1 ; fc = -1 ; tr = -1 ; tc = -1
'Step 2 : Scan the entire board
for r = 0 to BOARD_SIZE - 1
for c = 0 to BOARD_SIZE - 1
'Step 3 : find AI Knights
if board[r][c] = AI_PLAYER then
'Step 4 : Test all 8 moves
for k = 0 to 7
nr = r + knight_dy[k]
nc = c + knight_dx[k]
'Step 5 : validate the move
if is_valid_knight_move(r, c, nr, nc, AI_PLAYER) then
'Step 6 : prioritize to capture
if board[nr][nc] = HUMAN then
do_move(r, c, nr, nc)
last_ai_fr = r ; last_ai_fc = c
last_ai_tr = nr ; last_ai_tc = nc
current_turn = HUMAN
return
endif
'Step 7 : first valid non-capture move
if fr = -1 then
fr = r ; fc = c ; tr = nr ; tc = nc
endif
endif
next
endif
next
next
'Step 8 : if no capture was found
if fr <> -1 then
do_move(fr, fc, tr, tc)
last_ai_fr = fr ; last_ai_fc = fc
last_ai_tr = tr ; last_ai_tc = tc
endif
current_turn = HUMAN
endfuncRE: Knightbridge - johnno56 - 04-09-2026
Hey! Pocket sized! Well done! Cool...
RE: Knightbridge - kevin - 04-10-2026
Thanks for posting these Johnno and Micha, great fun. I really enjoy puzzle games, and games like these, but struggle with the game logic, particularly when computer opponents are involved. I guess I need to try harder
