Hi Maohai...
I wonder if the only issue with using "point mode" is the size of the
points, then perhaps you could use "setPointSize()" to make them show up
larger? (display.getGraphicsModeCOntrol().setPointSize(5.f) for example)
tom
maohai huang wrote:
One user requirement is to plot a million points and pick out
interesting part to zoom in until individual points are resolved
on the screen. From my test the fasted way to draw a large
number of points is plotting in (x->y) with setPointMode(true).
Each point then is a pixel. I suppose this is not the same as drawing
everypoing with VisADPointArray? Anyways in this mode, each point
is so small that the out liers are easy to overlook. So I start
experimenting with drawing with shapes. There is precisely one
shape at a time, though it is drawn a million times from the
user point of view. Now it looks like there is no way to get
around having at least an array of indices of large size created,
and having this array referenced when each point is plotted.
Yes it is possible to extend what visad does by default in
order to save memory and execution time. but I am
concerned by being tied too much to the unexposed internals
of visad to gain performance.
maohai
--
Tom Whittaker (tomw@xxxxxxxxxxxxx)
University of Wisconsin-Madison
Space Science and Engineering Center
Cooperative Institute for Meteorological Satellite Studies
Phone/VoiceMail: 608.262.2759
