There seems to be a problem with datum shifts and the version of the PROJ4 library that comes with gvSIG OADE. I'll take a closer look next week.
Ben ----- Original Message ----- > Hello, > > 50m is with OADE 2010 !!! > With gvsig 1.9 it's only 1.4 m (that is right with the precision of > the datum shift) > > If I create an user CRS with a copy of 27561 where I only change the > central meridian, I have the same result that with your proposal of > user CRS. I think that there is a problem with meridian "non Grenwich" > in lambert conformal conic 1SP. > > > Regards, > > Michel Bouillot > > ----- Mail Original ----- > De: "Bouillot Michel" <[email protected]> > À: "Users and Developers mailing list" > <[email protected]> Envoyé: Vendredi 16 Juillet 2010 > 11:08:16 > Objet: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > > Hello, > > Thanks for the answer. > The process works but I find an error of about 50m. > I take time to study it and I tell you. > > Regards > > Michel Bouillot > > ----- Mail Original ----- > De: "Juan Lucas Dominguez Rubio" <[email protected]> > À: "Users and Developers mailing list" > <[email protected]>, "Users and Developers mailing > list" <[email protected]> > Envoyé: Vendredi 16 Juillet 2010 10:04:27 > Objet: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > > > Hello, Michel: > > I think there's some confusion about the meaning of the EPSG codes. > According to spatialref.org, the PRJ file for EPSG:27561 is this: > > http://spatialreference.org/ref/epsg/27561/prj/ > > But that file is not like the one that comes with your shapefile. > > gvSIG is probably using the definition found in the spatialref.org > website, so that's why your shapefiles do not match if you select > EPSG:27561 when adding that file to your view. > > According to spatialref.org, the CRS that matches your PRJ file is > 'NTF Lambert Zone 1 France 2SP' (code SR-ORG:6910): > > http://spatialreference.org/ref/sr-org/6910/prj/ > > So all you have to do is declare it as a user-defined CRS in gvSIG. > > This has worked for me (I'll refer to your files as montreuil_2154.shp > and montreuil_27561.shp): > > - from the project manager, click 'New' to create a new view. Select > it (without opening it) and click on 'Properties' > - clic on the [...] button to change the view's CRS > - choose 'Type: user CRS' and click on 'New' > - choose the 'From WKT' option and paste this paragraph in the text > box: > > PROJCS["unnamed",GEOGCS["unnamed > ellipse",DATUM["unknown",SPHEROID["unnamed",6378249.2,293.4660200000053],TOWGS84[-168,-60,320,0,0,0,0]],PRIMEM["Greenwich",0],UNIT["degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",48.5985227778],PARAMETER["standard_parallel_2",50.3959116667],PARAMETER["latitude_of_origin",49.5],PARAMETER["central_meridian",2.3372291667],PARAMETER["false_easting",600000],PARAMETER["false_northing",200000],UNIT["Meter",1],AUTHORITY["EPSG","12345"]] > > - click on 'Finalize' and 'Accept'. You'll see that gvSIG refers to > the new CRS as 'USR:1' or similar. > - click 'Accept' again and open the view > - add the file montreuil_27561.shp without any additional option > because we know it's the same CRS of the view. > - go to the 'Add file' option again, choose the file > montreuil_2154.shp and before clicking on 'Accept', click on the > button to indicate the CRS of the file that is being added. Search for > EPSG:2154 (this one has no problem, you can use it) and select it, > then you need to choose the 'Manual transformation' option in the > transformation combo box. The seven parameters are: > > 168 > 60 -320 > 0 0 > 0 0 > > - click 'Accept' on all the following dialogs, and both shapefiles > should match. There is a small error of about 1.5 m, but I don't think > that's a problem for you. > > Does this process work for you? > > The CRS you have defined should be available from now on, but you will > have to type the seven parameters each time from the 'Manual > transformation' option. > > Those seven parameters are valid if the view is in 'NTF Lambert Zone 1 > France 2SP'. If the view is in EPSG:2154 and you add a shapefile in > 'NTF Lambert Zone 1 France 2SP', you'll have to reverse the sign of > the parameters. > > If you don't want to deal with user CRS and parameters inside gvSIG, > you can reproject your shapefiles before starting gvSIG. There is a > nice free program that does that: > > http://fwtools.maptools.org > > The command would be something like: > > ogr2ogr -f "ESRI Shapefile" -s_srs epsg:2154 -t_srs epsg:27561 > new_file.shp old_file_2154.shp > > (but again, we should check the meaning of EPSG:27561 in that case) > > > Regards, > > Juan Lucas Domínguez Rubio > --- > > Prodevelop SL, Valencia (España) > > Tlf.: 96.351.06.12 -- Fax: 96.351.09.68 > http://www.prodevelop.es > --- > > > De: [email protected] en nombre de Bouillot > Michel Enviado el: jue 15/07/2010 14:22 > Para: Users and Developers mailing list > Asunto: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > > > Hello, > > I think that you are right. > > I join shapefiles in both EPSG. > > Thanks for the tests. > > Regards, > > Michel Bouillot > > ----- Mail Original ----- > De: "Juan Lucas Dominguez Rubio" <[email protected]> > À: "Users and Developers mailing list" > <[email protected]>, "Users and Developers mailing > list" <[email protected]> > Envoyé: Jeudi 15 Juillet 2010 13:29:45 > Objet: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > > > Hello, I think there's a misunderstood. > > gvSIG is able to do on-the-fly reprojection (this is what Michel > needs, I think). > > But I'm afraid that, even if he follows the right steps to do it, the > result will be wrong because (I think) gvSIG does not know the right > parameters to perform that conversion (between EPSG:2154 and > EPSG:27561). > > There have been problems with the French projections in the past, and > I'm not sure if they were caused by a bug in gvSIG or in the libraries > used by gvSIG (especially Proj4). > > Michel: can you please send to the list two little shapefiles (one in > EPSG:2154 and the other in EPSG:27561) that should match but do not > match in gvSIG? So we can also do some tests. > > Regards, > > > Juan Lucas Domínguez Rubio > --- Prodevelop SL, Valencia (España) > > Tlf.: 96.351.06.12 -- Fax: 96.351.09.68 > http://www.prodevelop.es > --- > > > De: [email protected] en nombre de Bouillot > Michel Enviado el: jue 15/07/2010 13:02 > Para: Users and Developers mailing list > Asunto: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > > > Hi, > > Thanks for this explanation. > > I find GVSIG very good but in France we have just changed of RS. We > begin to have data in the 2 RS. > The reprojection in the view would be very pactical ! > Is there a hope for a such function in the futur ? > > Regards > > Michel Bouillot > > > ----- Mail Original ----- > De: "Guillermo Tamburini" <[email protected]> > À: "Users and Developers mailing list" > <[email protected]> Envoyé: Jeudi 15 Juillet 2010 > 12:43:50 > Objet: Re: [Gvsig_english] trouble with EPSG 2154 and 27561 > > Hi, > > In fact, you can't correctly represent data in different reference > systems in the same View (without reporojecting, it have no sense). > > There are some software applications which applies automatically the > reprojection, but it is not the case in gvSIG with vector layers. > > First of all, you have to select the correct RS for your View, and > then load the data (the target RS you are going to work). > > Otherwise, you will see your data but in a incorrect situation. In > other utm spindle, or displaced... > > If your data is in different RS, you will have to reproject it. > Goprocessing tools->Data Conversion->Reproject; the layer in the not > current projection to the current projection. > > Regards > > > Bouillot Michel wrote: > > > > > Hello, > > I try to open in the same view one shp in EPSG 2154 and one SHP in > EPSG 27561 but it don't match correctly. There is a problem with the X > like a translation witch have a value who seems to be the difference > between Greenwich and Paris meridian. > > How to correct this trouble ? > > regards > > Michel Bouillot > Chef de projet SIG > 01 48 70 63 23 / [email protected] > Ville de Montreuil / Direction Urbanisme et Habitat > Service Études Développement Urbain > 3, rue de Rosny / 93100 Montreuil > > > _______________________________________________ Gvsig_internacional > mailing list [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional > > -- Guillermo Tamburini Beliveau > Proyecto gvSIG > Consellería de Infraestructuras y Transportes (GVA) > Valencia (Spain) > _______________________________________________ Gvsig_internacional > mailing list > [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional > > _______________________________________________ Gvsig_internacional > mailing list > [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional > > _______________________________________________ Gvsig_internacional > mailing list > [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional > > _______________________________________________ Gvsig_internacional > mailing list > [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional > > _______________________________________________ Gvsig_internacional > mailing list > [email protected] > http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional ------ Files attached to this email may be in ISO 26300 format (OASIS Open Document Format). 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