I am not sure that I completely understand what it is that you are trying to do.
However, one thing from your existing code. It
might be more advantageous to change it to:
ArrayList points= new ArrayList();
points.Add(new Point(1, 100));
.....
as, if you are drawing the chances are that you will have to convert your
itemCoor
to a
Point
at some time. As I said earlier, though, this would depend on exactly what it is that you are trying to do.
Later, you talk about drawing circles and for that you will need more than just an X and a Y coordinate.
So if you could explain your problem slightly differently, you might get more help