[Mapserver-users] Re: Using Mapserver & GDAL to find elevation

[Frank Warmerdam]

Arthur, John wrote:
> Hello all,
> 
> 	I have a project where I need to be able to find the ground elevation 
 >of coordinates on the fly.  The file format we have is supposedly a proprietary
 >format, but I believe it is close to the "ArcInfo Binary Grid".  How would I go
 >about finding the elevation using mapscript (or some other way)?  Will mapserver
 >even read this format (by way of GDAL/OGR)?

John,

GDAL will read Arc/Info Binary Grids, so if it is sufficient close to this,
it may work.

However, currently MapServer and MapScript do not provide a way to query
raster values.  The only thing you can do with rasters is render them in a
mapview.

There is an intent to get query operations (in the usual mapserver sense)
working for rasters as well as vectors.  At that point there might be some
mechanism provided for reading query results back from within MapScript.
But that isn't going to be immediate.

Best regards,

-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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