function crosses = crossesLine(xOld, yOld, x, y, xLine, yLine)
    p1=[xOld, yOld];
    q1 = [x,y];
    p2 = [xLine(1), yLine(1)];
    o1 = orientationMy(p1, q1, p2);
    o2 = orientationMy([xOld, yOld], [x,y], [xLine(2), yLine(2)]);
    o3 = orientationMy([xLine(1), yLine(1)], [xLine(2), yLine(2)], [xOld, yOld]);
    o4 = orientationMy([xLine(1), yLine(1)], [xLine(2), yLine(2)], [x, y]);

    crosses = 0;
    if (o1 ~= o2)
        if(o3 ~= o4)
            crosses = 1;
        end;
    end;

    return;
end


function ret = orientationMy(p,q,r)
    val = (q(2) - p(2)) * (r(1) - q(1)) - (q(1) - p(1)) * (r(2) - q(2));


    if val == 0
        ret = 0; %coliner
    else
        if val > 0
            ret = 1; %clockwise
        else
            ret = 2; %coutnerclockwise
        end;
    end;

    return;
end