-0 from me. I understand the need and the rationale but I wish it wasn't necessary to hijack the EPSG authority.
Michael On 29 April 2011 09:11, Ian Turton <[email protected]> wrote: > On 28 April 2011 05:37, Andrea Aime <[email protected]> wrote: >> Hi, >> some months ago I started a discussion on GeoServer devel about >> adding support for a new EPSG code, EPSG:0. >> (if you want to review that discussion see here: >> http://osgeo-org.1803224.n2.nabble.com/Generic-cartesian-CRS-code-zero-td6136122.html) >> >> ESPG:0 would represent pure cartesian data, lack of any referencing, and >> would >> thus be associated to DefaultEngineeringCRS.GENERIC_2D, which is designed to >> be >> a lenient wildcard CRS, from the javadoc: >> > > +1 for me (though I can already see newbies being confused by it :-) >> ---------------- >> >> A two-dimensional wildcard coordinate system with x, y axis in metres. >> At the difference of CARTESIAN_2D, this coordinate system is treated >> specially by the >> default coordinate operation factory with loose transformation rules: >> if no transformation >> path were found (for example through a derived CRS), then the >> transformation from this >> CRS to any CRS with a compatible number of dimensions is assumed to be the >> identity transform. This CRS is usefull as a kind of wildcard when no >> CRS were explicitly specified. >> >> --------------- >> >> The only different would be that this one would be constructed so that it >> reports being EPSG:0 as being its "name". >> >> The idea behind EPSG:0 is to be able to handle non georeferenced data, >> or data that is expressed in some unkonwn coordinate system. >> This would allow to natively handle CAD data in vector land and plain >> images in raster land still using our GeoTools Feature/Coverage concepts, >> and avoid users to try and force EPSG:4326 in it instead (because it's often >> the only code they remember). >> >> As far as I can see this fits well with our existing code base, that already >> uses in some places DefaultEngineeringCRS.GENERIC_2D when no >> native CRS could be found, this work would just give it a name. >> >> Gabriel on the old thread raised a good point that the WMS 1.3 spec also has >> CRS:1 as the identifier to be used for the same purpose. >> I'm not going to go down that road because this would require making a large >> amount of changes to many bits of existing code assuming the authority >> is always going to be ESPG, both in GeoTools and GeoServer. >> The day we go there and allow the library to function properly without those >> assumption its going to be easy to add a further alias to that CRS >> and have it respond as CRS:1 as well. >> >> To wrap up, I'd like to add a new authority factory in referencing that >> adds support for that code and then check that base stores and coverage >> readers are working properly with it. >> Since this is an addition it's not going to break code not using it, >> thus I propose to commit the changes on both trunk and 2.7.x >> >> Opinions? >> >> Cheers >> Andrea >> >> -- >> ------------------------------------------------------- >> Ing. Andrea Aime >> GeoSolutions S.A.S. >> Tech lead >> >> Via Poggio alle Viti 1187 >> 55054 Massarosa (LU) >> Italy >> >> phone: +39 0584 962313 >> fax: +39 0584 962313 >> >> http://www.geo-solutions.it >> http://geo-solutions.blogspot.com/ >> http://www.youtube.com/user/GeoSolutionsIT >> http://www.linkedin.com/in/andreaaime >> http://twitter.com/geowolf >> >> ------------------------------------------------------- >> >> ------------------------------------------------------------------------------ >> WhatsUp Gold - Download Free Network Management Software >> The most intuitive, comprehensive, and cost-effective network >> management toolset available today. Delivers lowest initial >> acquisition cost and overall TCO of any competing solution. >> http://p.sf.net/sfu/whatsupgold-sd >> _______________________________________________ >> Geotools-devel mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/geotools-devel >> > > > > -- > Ian Turton > > ------------------------------------------------------------------------------ > WhatsUp Gold - Download Free Network Management Software > The most intuitive, comprehensive, and cost-effective network > management toolset available today. Delivers lowest initial > acquisition cost and overall TCO of any competing solution. > http://p.sf.net/sfu/whatsupgold-sd > _______________________________________________ > Geotools-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/geotools-devel > ------------------------------------------------------------------------------ WhatsUp Gold - Download Free Network Management Software The most intuitive, comprehensive, and cost-effective network management toolset available today. Delivers lowest initial acquisition cost and overall TCO of any competing solution. http://p.sf.net/sfu/whatsupgold-sd _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
