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[Support #TSL-357793]: Re: HDF 4 and HDF-EOS in Java netcdf 4.0!

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  • Subject: [Support #TSL-357793]: Re: HDF 4 and HDF-EOS in Java netcdf 4.0!
  • Date: Mon, 10 Mar 2008 13:28:34 -0600
Hi Peter:

> Hi John,
>
> One thing that I've done in my own work is to implement classes
> relating to the GCTP library which we use for CoastWatch HDF data, and
> which HDF-EOS uses as well.  I still use the GCTP C library for the
> actual (lat,lon) -> (x,y) conversion, although I did implement a
> scheme that can invoke a Java equivalent transform if one is
> available.  I had to do a lot of messing around with GCTP spheroids in
> order to do datum shifting between WGS 84 and some satellite data we
> were using that was mapped to a perfect sphere.  Some other things
> too, like a GUI that lets you select and visualize the map projection
> for a set of GCTP parameters, and coast/grid line rendering and
> polygon filling code that is somewhat sensitive to special cases of
> map projection discontinuities.  Not sure how you're handling the GCTP
> angle from Java?

We have implemented a few common projections in Java, but would love to use a
standard Java library instead/in addition. Also, we are just getting to
understand datums and so on. So any advice would be welcome.

Also, what about handling HDF-EOS swath coordinate
> systems, are you having any fun with that?

Again, just starting to do that. Our first task is to just be able to read the
bits correctly. If you get a chance to test, lest us know any problems that you
see.



Ticket Details
===================
Ticket ID: TSL-357793
Department: Support netCDF Java
Priority: Normal
Status: Open