Flash MX 2004 Games : Art to ActionScript

Chapter 16: Board games
Once the player’s chosen square has been checked and found to be legal we need to update
the display. The function ‘adjustBoard’, Listing 16.7, does that. The start location and current
player are passed to the function and then the values stored in the ‘flip’ array set by the ‘scanBoard’
function calls are used. Again we use eight calls to another function with the direction passed to
each call.
1 function adjustBoard(row, col, piece){
2
3
var opponent;
4 if (piece==PLAYER){
5 opponent = COMPUTER;
6 }else{
7 opponent = PLAYER;
8
9
}
10 if (flip[0]) flipLine(row, col, piece, opponent, 1, 0);
11 if (flip[1]) flipLine(row, col, piece, opponent, 0, 1);
12 if (flip[2]) flipLine(row, col, piece, opponent, -1, 0);
13 if (flip[3]) flipLine(row, col, piece, opponent, 0, -1);
14 if (flip[4]) flipLine(row, col, piece, opponent, -1, -1);
15 if (flip[5]) flipLine(row, col, piece, opponent, 1, -1);
16 if (flip[6]) flipLine(row, col, piece, opponent, 1, 1);
17
18 }
if (flip[7]) flipLine(row, col, piece, opponent, -1, 1);
Listing 16.7
As you can see from Listing 16.7, the function ‘flipLine’ does the actual work of manipulating the
display.
1 function flipLine(row, col, piece, opponent, incX, incY){
2 var x, y, name;
3
4 x = col + incX;
5 y = row + incY;
6 name = "board" + y + "_" + x;
7
8 while(eval(name)._currentframe==opponent){
9 eval(name).gotoAndStop(piece);
10 x += incX;
11 y += incY;
12 name = "board" + y + "_" + x;
13 }
14 }
Listing 16.8
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