Function floodfill(x,y,old_color,new_color:Integer; map : Map_gen) : Integer;

var
   x2,y2:Integer;

begin
   if map[x,y] <> old_color then Exit();

   map[x,y] := new_color;
   for x2 := -1 to 1 do
      begin
         for y2 := -1 to 1 do
            begin
               floodfill(x + x2,y + y2,old_color,new_color,map)
            end;
      end;
end;