Useability issues

• To: visad-list@xxxxxxxxxxxxx
• Subject: Useability issues
• From: Cristy <cristy@xxxxxxxxxxxxxxxxxxxx>
• Date: Tue, 23 Jun 1998 12:11:44 -0400 (EDT)

Thanks to VisAD and Bill and Steve I have nearly completed my textual
data mining visualization project.  I'm now working on fine-grain
usability issues.  In particular I have a 3-D surface that represents
the number of documents related to a particular word stem.  As I move a
yellow dot across the surface the corresponding stem is highlighted in
a JFC table.  The usability problem I am having relates to trying to
match the dot with a peak in the 3-D surface.  I can move the dot to
what I think is the peak and if I rotate the surface I can see I've
missed it by a mile (well not quite that far).  If I keep moving the
dot and spinning the surface I can usually intersect the dot with a
particular peak on the surface after about 5 or 6 tries.  This problem
is illustrated here:

  http://www.wizards.dupont.com/cristy/images/global-som.jpg

One way to improve this is to show three different views of the surface
and move the dot in one window and visualize it's movements in the
other two.  The problem with this idea is screen real-estate.  There
just isn't enough for three views while still having the surface large
enough to easily distinguish detail.

Another way would be to have the dot cast a shadow on the surface to
help give visual cues as the dot moves toward a surface.  Can this be
done?  How?

Right now the surface is monochrome.  I would like to force the peaks
to be almost pure white as if it had snow.  It sort-of does that now
but is not dramatic enough to give the proper visual cues.

Another problem I am having is when there are just a few stems the
surface needs smoothing.  Is there an easy operation to effect this?
This problem is illustrated here:

  http://www.wizards.dupont.com/cristy/images/local-som.jpg

As always, thanks in advance for any help you may offer.