Re: [Geoserver-users] geoserver, gwc and 900913
On Wed, Sep 11, 2013 at 8:04 AM, John Callahan wrote: > Part of my question may be academic but, like many technical things, it > becomes practical when getting into the details. I currently have 20 - 30 > GB used by geowebcache for SRS 900913 (total for about 12 raster layers). > When a request comes in using 3857, it will not use the 900913 cache. To > use cache for 3857, I would need to duplicate the cache for each layer. It > comes down to which is used more often and if I want to support caches for > both. > > I agree that I can alter the default SRS for geowebcache anytime. I would > think 3875 should be the default and we should move away from 900913, > unless everyone is still using 900913 much more than 3857. > Meh, my current perception is that both are used, 900913 more used by the pratictioners, 3857 (not 3875!) more by people paying more attention to OGC details (just made a search with google for EPSG:900913, returns 133k results, EPSG:3857 returns 149k results). It would be nice to have them both and have some internal transformer that "canonicalizes" one onto the other to avoid duplicating the tile storage. Who's going to develop/sponsor it? :-) Cheers Andrea -- == Our support, Your Success! Visit http://opensdi.geo-solutions.it for more information. == Ing. Andrea Aime @geowolf Technical Lead GeoSolutions S.A.S. Via Poggio alle Viti 1187 55054 Massarosa (LU) Italy phone: +39 0584 962313 fax: +39 0584 1660272 mob: +39 339 8844549 http://www.geo-solutions.it http://twitter.com/geosolutions_it --- -- How ServiceNow helps IT people transform IT departments: 1. Consolidate legacy IT systems to a single system of record for IT 2. Standardize and globalize service processes across IT 3. Implement zero-touch automation to replace manual, redundant tasks http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk___ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
Re: [Geoserver-users] geoserver, gwc and 900913
Hi John, just an idea which wouldn't work in windows but I would like to know what would happen if you have the other (empty) directory as a symbolic link pointing to the directory that has the tiles. Haven't tried that but it should work in the Unix/Linux world. Cheers Christian - Dr Christian Maul Project Manager Information Services Branch Department of Sustainability and Environment Level13, Marland House, 570 Bourke Street Melbourne 3000 PO Box 500, East Melbourne Vic 3002 Telephone:+61-3-8636 2325 Telefax: +61-3-8636 2813 -- View this message in context: http://osgeo-org.1560.x6.nabble.com/geoserver-gwc-and-900913-tp5077103p5077210.html Sent from the GeoServer - User mailing list archive at Nabble.com. -- How ServiceNow helps IT people transform IT departments: 1. Consolidate legacy IT systems to a single system of record for IT 2. Standardize and globalize service processes across IT 3. Implement zero-touch automation to replace manual, redundant tasks http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk ___ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
Re: [Geoserver-users] geoserver, gwc and 900913
Part of my question may be academic but, like many technical things, it becomes practical when getting into the details. I currently have 20 - 30 GB used by geowebcache for SRS 900913 (total for about 12 raster layers). When a request comes in using 3857, it will not use the 900913 cache. To use cache for 3857, I would need to duplicate the cache for each layer. It comes down to which is used more often and if I want to support caches for both. I agree that I can alter the default SRS for geowebcache anytime. I would think 3875 should be the default and we should move away from 900913, unless everyone is still using 900913 much more than 3857. - John John Callahan Research Scientist Delaware Geological Survey University of Delaware http://www.dgs.udel.edu john.calla...@udel.edu On Wed, Sep 11, 2013 at 1:36 AM, cmaul wrote: > John, > > a truly academic question. Yes - in theory. However, the widespread use of > 900913 is a result of the Cinderella treatment of Google by the spatial > fraternity and the past confusion with EPSG:3587 and EPSG:3857. > > What geowebcache uses as a default is entirely up to you because in the > geowebcache-core-context.xml is the following tag: > > > > > > > > > Question 3: No why, they are the same projections. > > Cheers > > Christian > > > > - > > > Dr Christian Maul > Project Manager > > Information Services Branch > Department of Sustainability and Environment > Level13, Marland House, 570 Bourke Street > Melbourne 3000 > > PO Box 500, East Melbourne Vic 3002 > > > Telephone:+61-3-8636 2325 > Telefax: +61-3-8636 2813 > -- > View this message in context: > http://osgeo-org.1560.x6.nabble.com/geoserver-gwc-and-900913-tp5077103p5077185.html > Sent from the GeoServer - User mailing list archive at Nabble.com. > > > -- > How ServiceNow helps IT people transform IT departments: > 1. Consolidate legacy IT systems to a single system of record for IT > 2. Standardize and globalize service processes across IT > 3. Implement zero-touch automation to replace manual, redundant tasks > http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk > ___ > Geoserver-users mailing list > Geoserver-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/geoserver-users > -- How ServiceNow helps IT people transform IT departments: 1. Consolidate legacy IT systems to a single system of record for IT 2. Standardize and globalize service processes across IT 3. Implement zero-touch automation to replace manual, redundant tasks http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk___ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
Re: [Geoserver-users] geoserver, gwc and 900913
John, a truly academic question. Yes - in theory. However, the widespread use of 900913 is a result of the Cinderella treatment of Google by the spatial fraternity and the past confusion with EPSG:3587 and EPSG:3857. What geowebcache uses as a default is entirely up to you because in the geowebcache-core-context.xml is the following tag: Question 3: No why, they are the same projections. Cheers Christian - Dr Christian Maul Project Manager Information Services Branch Department of Sustainability and Environment Level13, Marland House, 570 Bourke Street Melbourne 3000 PO Box 500, East Melbourne Vic 3002 Telephone:+61-3-8636 2325 Telefax: +61-3-8636 2813 -- View this message in context: http://osgeo-org.1560.x6.nabble.com/geoserver-gwc-and-900913-tp5077103p5077185.html Sent from the GeoServer - User mailing list archive at Nabble.com. -- How ServiceNow helps IT people transform IT departments: 1. Consolidate legacy IT systems to a single system of record for IT 2. Standardize and globalize service processes across IT 3. Implement zero-touch automation to replace manual, redundant tasks http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk ___ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
[Geoserver-users] geoserver, gwc and 900913
I've been starting to use GeoServer caching (geowebcache) more often and have a question regarding the caching for the web mercator or Google projection. The "official" EPSG code for the web mercator projection is EPSG:3857. GeoServer does support this by default. However, geowebcache uses 900913 as a default gridset. Perhaps that should be 3857? As well, the default definition for 3857 in GeoServer is missing the datum transformation parameters. Adding something like the following should work. TOWGS84[0,0,0,0,0,0,0], (In PROJ.4 format, "+nadgrids=@null" could also be added to not use any grid shift fileand apply a zero shift.) It was also mentioned in the article http://alastaira.wordpress.com/2011/01/23/the-google-maps-bing-maps-spherical-mercator-projection/(good summary), that the prpjection name should be changed to: PROJECTION["Mercator"] Apparently, 3857 is not in spatialreference.org but these two are very close. http://spatialreference.org/ref/sr-org/6864/ http://spatialreference.org/ref/sr-org/7483/ So, with all that said, my questions are: 1) Should GeoWebCache use 3857 rather than 900913 as the default web mercator gridset? 2) Should the definitions of 3857 and/or 900913 be changed in GeoServer? or maybe entries can be added to override these reference systems in \geoserver_data\user_projections? 3) Would anyone recommend building cache tile sets for both 3857 and 900913 (since clients may be use either one)? Thanks for your help/. - John John Callahan Research Scientist Delaware Geological Survey University of Delaware http://www.dgs.udel.edu john.calla...@udel.edu -- How ServiceNow helps IT people transform IT departments: 1. Consolidate legacy IT systems to a single system of record for IT 2. Standardize and globalize service processes across IT 3. Implement zero-touch automation to replace manual, redundant tasks http://pubads.g.doubleclick.net/gampad/clk?id=5127&iu=/4140/ostg.clktrk___ Geoserver-users mailing list Geoserver-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geoserver-users
