[Gdal-dev] RE: GDAL netcdf convention CF support

[Ron Lake]

Hi,

This would seem a natural extension to the OGC WFS specification.  Note
that GML incorporates (under features):
Coverages and support for time (as well as temporal reference systems)
and dynamic features.  Extending MapServer to being a WFS that supports
these features would be a good place to start.  You can likely go some
distance with the existing WFS spec.  What is needed of course is
support for 1) temporal data types (MapServer extension) 2) temporal
operators (WFS extension) .. 

Cheers

Ron

-----Original Message-----
From: owner-galeon at unidata.ucar.edu
[mailto:owner-galeon at unidata.ucar.edu] On Behalf Of Frank Warmerdam
Sent: August 21, 2005 1:41 PM
To: Gerry Creager N5JXS
Cc: gdal-dev at lists.maptools.org; galeon at unidata.ucar.edu
Subject: Re: GDAL netcdf convention CF support


On 8/21/05, Gerry Creager N5JXS <gerry.creager at tamu.edu> wrote:
> Frank, et al,
> 
> I think we need to be thinking either about making GDAL more 
> interested in 3D/4D datasets, as that's coming whether we're ready or 
> not... in fact, for me, it's already here.. and then see if we need to

> consider forking or augmenting Mapserver to accommodate it.
> 
> I see a lot of conceptual problems for Mapserver, and, for that 
> matter, a LOT of GIS packages in incorporating 3D/4D data, and 
> presenting it properly.  This has been an issue for GIS practitioners
since just about
>   forever: They think in 2 dimensions and can't, as a group, 
> appreciate the need for either vertical, or time.  They represent time

> series data as a series of static images.
> 
> I see, in Mapserver, a potential interface.  It's open-source and thus

> maleable for applications like this.  It won't be simple or 
> straightforward, and in the end, Mapserver might serve solely as an 
> example framework for a new 3D/4D display/dissemination tool, but it
> *is* a starting point.
> 
> I'm kinda thinking about a melding of Mapserver and IDV, in th elong 
> run.

Gerry,

The idea of extending mapserver and GDAL to better support 3D/4D
datasets has been brought up a few time, and I have generally been quite
... conservative ... in response.  I am concerned about substantial
complication and turmoil in the interfaces of both.

My personal opinion is that in the shorter term it would make more sense
to have a distinct multi-dimensional WCS server implemented that might
derive some code from MapServer, but that would otherwise be quite
distinct.  It would ignore all the vector and "portral" related support
in MapServer in favor of focusing on serving n-dimensional raster data 
via WCS.  

There could be an n-dimensional equivelent to GDAL as well, that might
even include a GDAL plugin for 2D datasets, but that would have it's own
interfaces that are more organized to n-dimensional data.  Perhaps it
could even be closely related to one of the existing n-dimensional file
format libraries like netcdf or HDF (my understanding is that the next
general netcdf is based on HDF5). 

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam,
warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent