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% Meta Chief
% May 20, 2009
% TicTacToe

/*
A two player game of tic tac toe
*/

var mouseX, mouseY, mouseB : int % Stores mouse properties

type BoardType : array 1 .. 3, 1 .. 3 of int % Grid points type

var board : BoardType %Stores grid points

const squareSize := 40 % Size of each square on the board

proc InitBoard % Assigns all grid points to a value of zero
for a : lower (board) .. upper (board)
for b : lower (board) .. upper (board)
board (a, b) := 0
end for
end for
end InitBoard

proc DrawBoard % Depending on the value of a grid point, the board is drawn
for a : lower (board) .. upper (board)
for b : lower (board) .. upper (board)
drawbox (a * squareSize, b * squareSize, a * squareSize + squareSize, b * squareSize + squareSize, black)
if board (a, b) = 1 then % If the grid point value is 1 an x is drawn
drawline (a * squareSize, b * squareSize, a * squareSize + squareSize, b * squareSize + squareSize, black)
drawline (a * squareSize + squareSize, b * squareSize, a * squareSize, b * squareSize + squareSize, black)
elsif board (a, b) = 2 then % If the grid point value is 2 a circle is drawn
drawoval (a * squareSize + squareSize div 2, b * squareSize + squareSize div 2, squareSize div 2, squareSize div 2, black)
end if
end for
end for
end DrawBoard

var turn : int := 1 % Stores the players' turn
var turnCount : int := 0 % Counts the number of turns in total

proc UseMouse % Allow the user to use the mouse to change the value on the grid
for a : lower (board) .. upper (board)
for b : lower (board) .. upper (board)
var x, y : int
if Mouse.ButtonMoved ("down") then
var buttonnumber, buttonupdown : int
Mouse.ButtonWait ("down", x, y, buttonnumber,
buttonupdown)
if mouseX div squareSize <= upper (board) and mouseY div squareSize <= upper (board) and mouseX div squareSize >= lower (board) and mouseY div squareSize >= lower (board) then
% If the mouse in on the board (to prevent out of range error)
if board (mouseX div squareSize, mouseY div squareSize) = 0 then
board (mouseX div squareSize, mouseY div squareSize) := turn % Turn represents an x or a cricle depending on the turn
if turn = 1 then
turn := 2
elsif turn = 2 then
turn := 1
end if
turnCount += 1
end if
end if
end if
end for
end for
end UseMouse

fcn CheckWin : int % Checks possivle win conditions
for i : 1 .. 2
if board (1, 1) = i and board (2, 2) = i and board (3, 3) = i then
result i
elsif board (1, 1) = i and board (1, 2) = i and board (1, 3) = i then
result i
elsif board (1, 1) = i and board (2, 1) = i and board (3, 1) = i then
result i
elsif board (2, 1) = i and board (2, 2) = i and board (2, 3) = i then
result i
elsif board (3, 1) = i and board (3, 2) = i and board (3, 3) = i then
result i
elsif board (3, 1) = i and board (2, 2) = i and board (1, 3) = i then
result i
elsif board (1, 3) = i and board (2, 3) = i and board (3, 3) = i then
result i
elsif board (1, 2) = i and board (2, 2) = i and board (3, 2) = i then
result i
end if
end for
result 0
end CheckWin

proc DrawWord (x, y, c : int, word : string) % Draws words with specified position and color
var fontID : int
fontID := Font.New ("mono:12:bold")
Font.Draw (word, x - (Font.Width (word, fontID) div 2), y, fontID, c)
Font.Free (fontID)
end DrawWord

proc ShowTurn % Displays the turn of the players
DrawWord (maxx div 2, maxy - 20, black, "Player " + intstr (turn))
end ShowTurn

proc Main
var winID : int
winID := Window.Open ("offscreenonly,graphics:200,200,position:centre,centre")
InitBoard % Initialises the game grid
loop
mousewhere (mouseX, mouseY, mouseB)
UseMouse
DrawBoard
ShowTurn
if CheckWin = 1 then
cls
DrawWord (maxx div 2, maxy div 2, black, "Player " + intstr (CheckWin) + " won!")
exit
elsif CheckWin = 2 then
cls
DrawWord (maxx div 2, maxy div 2, black, "Player " + intstr (CheckWin) + " won!")
exit
elsif turnCount = 9 and CheckWin = 0 then
cls
DrawWord (maxx div 2, maxy div 2, black, "Tie!")
exit
end if
View.Update
cls
end loop
end Main

% Main

Main

Author:	DemonWasp [ Wed Sep 16, 2009 11:56 pm ]
Post subject:	RE:Tic Tac Toe
In InitBoard: - Be aware that lower ( board ) and upper ( board ) will return only the length of the first dimension. While this code will work for square arrays (which is all you need), it won't work for anything non-square. In CheckForWin: - You don't need to check for both players, you just need to check that the parts of the array have the same value. If you compare (1,1) to (2,2) and find them to be equal and that (2,2) = (3,3), then you know that someone has won. You can then just use the value of any one of those squares to see who won. - You could also use for loops over the array to shorten the amount of code you'd have to write. In DrawWord: - With frequently-used resources like fonts, it's probably best to create them once, cache them, then free them only when you're really done with them. Right now, every time you DrawWord, Turing has to load the requested font before it can draw. Not bad though.

Author:	A.J [ Thu Sep 17, 2009 7:44 am ]
Post subject:	RE:Tic Tac Toe
Good job, metachief Well, I would suggest that you store the tic tac toe board in a one dimensional array instead of a two dimensional array. So, for example, the position (1, 1). would become 1, and the position (1, 2) would become 2, etc... (something like this: ____________ \| 1 \| 2 \| 3 \| \| 4 \| 5 \| 6 \| \| 7 \| 8 \| 9 \| ____________ Using a simple hashing function to hash coordinates on the board to a single integer would be pretty easy (for example, in this case, given x and y, (x, y) on the board is y + 3*(x-1)). And, this can make it easier to work with.