Reversi Valid Move Checker - matlab

Question

I've been doing an assignment which requires me to recreate reversi in matlab.
I have hit a break point where I can't manage to figure out how to do a section of code without turning it into linear indexing.
Essentially what I need to do is figure out a way to add a direction vector (i.e. [-1;0] to go vertically), to my already existing game_state vector in order to find the piece of data above it.
function legal = legalMove()
d_l = [0, -1];
d_r = [0, 1];
d_u = [-1, 0];
d_d = [1, 0];
d_ul = [-1, -1];
d_ur = [-1, 1];
d_dl = [1, -1];
d_dr = [1, 1];
directions = [d_l d_ul d_u d_ur d_r d_dr d_d d_dl];
valid_moves = zeros(8,8);
for ci = 1:8
for cj = 1:8
if game_state(ci,cj) == 0 %check element = 0 before continuing
for count = 1:8
d = directions(count);
selected =
while selected == player_number * -1 %while the selected piece is of enemy type
%move as long as you find your opponents stones
if you found at least 1 opponent stone and you end up on your own stone
else
end
end
end
else
end
end
end
end
My second issue after that, is the actual loop itself.
While I thought that a while loop could be used in order to find out whether to stay on the current direction, I cannot seem to figure out a way to do it myself.
Any assistance would be appreciated.
Thanks for your time!

Answer 1

Change directions to cell-array that contains strings:
...
directions = { 'd_l' 'd_ul' 'd_u' 'd_ur' 'd_r' 'd_dr' 'd_d' 'd_dl' };
...
Then next part of the code would go something like this (fill in the blanks!):
for count = 1:8
d = eval( directions{count} );
ti = ci+d(1);
tj = cj+d(2);
% Check if out of the board
...
% Number of enemy pieces you went over
cnt = 0;
selected = gamestate(ti, tj)
% Move while going over enemy pieces
while selected == player_number * -1
ti = ti + d(1);
tj = tj + d(2);
selected = gamestate(ti, tj);
% Check if out of the board
...
% Count pieces you went over
cnt = cnt + 1;
end
% Check if you moved over enemy pieces & whether you landed on your piece
...
end