Sally's Summit Summary

Paul Ramsey pramsey at REFRACTIONS.NET
Mon Jun 20 16:03:03 EDT 2005

I would be more tempted to put it in automatically, on the theory that 
when doing map files
(1) get it working
(2) make it fast

This is where some logging of layer data access times and render times 
would help people optimize. But right out of the gate newbies could get 
online a little easier. proj4 can be a bit of a hurdle for people.


Frank Warmerdam wrote:

> On 6/20/05, Paul Ramsey <pramsey at> wrote:
>>Thanks for the summary, I am sorry I missed the summit, but the Twins
>>were playing so we did baseball instead.
>>- Paul Spencer and I also talked about "magic projection" support. Many
>>formats have projection information embedded or alongside, so having to
>>redundently specify them in the map file is not the most user-friendly
>>approach. Like the "wms_extent", projection blocks should really only be
>>required "as necessary". I think this can be done relatively easily, by
>>adding some projection setting code into the LayerOpen area of each
>>driver, and agreeing on some heuristics:
>>o If there is a PROJECTION in the map file, then don't overwrite it.
> Paul, 
> I would note that there is already PROJECTION "AUTO" support in
> the OGR and GDAL driver code for MapServer.  But it only kicks in
> if the user requests "AUTO" as the projection.
> I am a bit leery about doing it without the user requesting it for
> fear that the system detect very slightly different coordinate systems
> (ie NAD83 and WGS84) that would cause alot of unnecessary 
> reprojection work.  I believe that is why the "AUTO" keyword was
> required in the past. 
> I would however like to see more automatic projection support working
> more widely in mapserver.
> Best regards,

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