Hi Vimal,
Use a UnionSet of Gridded2DSets. See Rivers.java in visad/examples/.
Doug
> Vimal Gopal wrote:
> 
> Hello Bill, Everyone,
> 
>     I was wondering whether anyone knew whether there is a way in
> VisAD to apply an overlay to VisAD displays.  By overlay, I mean,
> geopraphical boundries, long/lat lines, etc.  I'm guessing the way to
> do this is by using sets and to "connect the dots".  Any insight is
> appreciated.
> 
> Vimal B. Gopal
-- 
*----------------------------------------------------------------------*
| Doug Lindholm, Software Engineer          |  E-mail: lind@xxxxxxxx   |
| Research Applications Program             |   Phone: 303-497-8374    |
| National Center for Atmospheric Research  |                          |
| P.O. Box 3000                             |     There's no place     |
| Boulder, Colorado 80307-3000              |        like $HOME        |
*----------------------------------------------------------------------*