Hi Jim, Don, Andrew et al,
To add to Andrew and Don's comments:
The radar data file expected by RadarDisplay is known as a 6 level, run length
encoded data file. It is the simplest possible radar data format that we
generate.
We also generate 16 level and full volumetric data, but no work has been done on
this yet in Java/VisAD.
Don is absolutely right, that the CoordinateSystem class is where the real magic
lies.
Either Andrew or I could probably help if you need more information. What do you
want to do, and what else do you need?
Cheers,
James
[thanks for the great summary Don!]
Don Murray wrote:
> Andrew Donaldson wrote:
> >
> > > is there a contact point at the Australian
> > > Bureau of Meteorology who can/will share technical details?
> >
> > James Kelly is probably the best contact, try j.kelly@xxxxxxxxxx
> > James usually monitors this list, but he's away at the moment.
> > You're also welcome to ask me.
> >
> > > for example, the radar display (main) expects a data file,
> > > however the file is not in the ViasAD examples directory.
> >
> > This file should be the right format:
> > ftp://ftp.bom.gov.au/sample/IDBRA000/IDR02POL.txt
> >
>
> Since I've done a little bit of work on this, I'll add my $.02. These are my
> opinions based on conversations with James Kelly. If I misrepresent
> anything, I
> apologize in advance.
>
> The visad.bom.RadarDisplay class is really just a test program to display
> radar
> data files that the BoM distributes from their radar sites. The format is
> specific to the BoM (i.e. they are not NIDS files). RadarDisplay uses the
> RadarAdapter class that uses the RadarFile class which actually reads the data
> file. The data files are ASCII, and use a special compression scheme
> developed
> by the BoM. If you use the file that Andrew specified above, you need to
> rename
> it to radar.dat to use with RadarDisplay. You would also need the OUTLAUST
> map file, which you can get at
> ftp://ftp.unidata.ucar.edu/pub/dmurray/OUTLAUST.
>
> RadarDisplay will display the data either as a 2D image of reflection values
> mapped to RGB, or as a 3D display of the values with the reflection values
> mapped to RGB and ZAxis.
>
> The original goal of the visad.bom.Radar* classes was to be able to read these
> data files to display them in the BoM's AIFS displays. However, that goal has
> been superceded by the use of an ADDE server to collect the data files so
> further work on the RadarDisplay program is not likely (as far as reading the
> ASCII files).
>
> Of particular importance in this package (as far as displaying radar data) are
> the Radar*DCoordinateSystem classes which will transform range, azimuth (and
> elevation) to lat, lon, (alt) (3D versions in parens). Unidata and other
> groups
> at NCAR will be using these to develop programs for displaying the U.S. Level
> II
> NEXRAD data.
>
> As Andrew says, James is the best contact for questions on this package, but I
> hope this helps.
--
James Kelly
Regional Computing and Distributed Systems Bureau of Meteorology
PO Box 1289K Melbourne 3001, Australia
Phone: 61-3-9669-4724 Fax: 61-3-9669-4128 Email: J.Kelly@xxxxxxxxxx
