> > We clearly DO have to read FITS WCS headers!
>
> So I'll happily wait for Java AST.
Are we saying that the issue of a pure Java version of AST is back on
the table? If so maybe we need to get a group of interested parties
together to decide which bits of AST we really need now in Java, and which
bits can be put off to later. I am aware that I have probably not inspired
much confidence in the practicality of this project in the past, but maybe
having a few extra heads on the job may help.
What I have at the moment is a draft system which will read a FITS header
containing celestial coords (not spectral), and extract something
equivalent to a FrameSet. You can transform positions between the various
Frames in the FrameSet, but it misses out most of the things which make
AST really useful, such as:
- the ability to find conversions from one Frame to another. This means
for instance, that you can switch from galactic coords to RA/DEC, or from
wavelength to frequency, etc.
- there is no Plot class at all. In fact, will Java really be fast enough
to do all the calculations involved in tracing out a grid line??
- there is no way of cancelling out redundant steps within complex
Mappings.
David
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