Hi Stuart-
Sorry for the delay in responding.
Stuart Maclean wrote:
Hi Don, hmm your comments above have me thinking.  My app is web based, 
and I am using idv/visad classes in 'offscreen' mode.  I want to 
generate BufferedImages (sent to the web client as transparent pngs), 
using e.g. the getImage() call.
With the 'reduced overhead' to which you are referring, would I better 
off adding many Displayables to one DisplayMaster, and turning the 
visibility of each on and off to grab each BufferedImage, or use a 
separate DisplayMaster, each with a single Displayable?  The former is 
better in a web environment, since fewer objects to clean up when the 
user 'session' expires.
The overhead is in the initial rendering of the displayables.
So, if you add in lots of displayables and then say draw(),
you'll take the initial hit.  However, turning them on or off
(or removing any) should have not performance hit.
Don
*************************************************************
Don Murray                               UCAR Unidata Program
dmurray@xxxxxxxxxxxxxxxx                        P.O. Box 3000
(303) 497-8628                              Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
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