[Proj] Google maps of various flavors, and countries all overthe place.

Roger Oberholtzer roger at opq.se
Wed Oct 15 04:52:32 EDT 2008


On Wed, 2008-10-15 at 10:22 +0200, Roger Oberholtzer wrote:
> On Tue, 2008-10-14 at 17:04 -0400, Frank Warmerdam wrote:
> > Clifford J Mugnier wrote:
> > > Isn't what is being proposed a duplication of the EPSG database?
> > >  
> > > What would such a "compilation" offer that EPSG does not?
> > 
> > Cliff,
> > 
> > I imagine it would contain suggested PROJ.4 strings for national
> > coordinate systems (including some suggested towgs84 parameters
> > for datums).  The PROJ.4 strings are not a duplication of EPSG,
> > but it is true that the datum shift parameters might be.
> 
> That is it in a nutshell. It is fine to have a database that describes
> the proper values for parameters according to some 'standard'. But
> getting it into the EXACT form required for a specific country, in
> practice, and verified against some reference data set, is what I seem
> to miss. This includes command line, as well as C API parameter
> specifications. And, where possible, verification data. This is what I
> am suggesting.

Also, read
http://trac.osgeo.org/proj/wiki/FAQ#HowdoIuseEPSGcoordinatesystemcodeswithPROJ.4

I experience this issue regularly and as a result do not use the codes.
I set all the parameter strings. Often starting with the strings in the
database, but seldom ending up the same when eventually working as
needed.

-- 
Roger Oberholtzer

OPQ Systems / Ramböll RST

Ramböll Sverige AB
Kapellgränd 7
P.O. Box 4205
SE-102 65 Stockholm, Sweden

Office: Int +46 8-615 60 20
Mobile: Int +46 70-815 1696

And remember:

It is RSofT and there is always something under construction. 
It is like talking about large city with all constructions finished. 
Not impossible, but very unlikely.




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