RE: [mapserver-users] projection = geographer's pain
Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you want to show the whole map. So you can overlay more data sources in different projection in a single map. Try to set the layer PROJECTION as init=epsg:4326. Let us know... ciao ... pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Ven, Ottobre 24, 2008 16:55, Monier Clement wrote: Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order to perfectly overlay the GoogleMaps tile images (for the moment, my maps are slightly shifted north.) I've added this string at the end of the file epsg in /ms4w/proj/nad : 3785 +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +towgs84=0,0,0,0,0,0,0 +units=m [EMAIL PROTECTED] +no_defs But I don't know how to modify my request and mapfile in order to get the correct map. I've tried many combinations so far but with no success until now. Do I have to change the projection system of my shapefiles ? Is MapServer able to change projection between input and output ? Request : SRS=epsg:3785 MapFile : [Map section] METADATA wms_srs EPSG:4326 EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END [Layer section] METADATA wms_srs EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END With these settings, the pictures I got from MapServer are still shifted. Thanks for your help Clement ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: VS: [mapserver-users] projection = geographer's pain
there is something strange... :-) I normally project data in lat-lon wgs84 coordinates in world mercator. I declare latlon wgs as epsg:4326 or +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs and world mercator as +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs (http://spatialreference.org/ref/epsg/3395/) You use another declaration, that is the google mercator (http://spatialreference.org/ref/user/google-projection/) that is slightly different... I don't know well Proj4, but I believe that this is not the core of the problem... I know (maybe I do not know well) that the projection of the map is different from the projection of the layer bcause the layer data source (shapefile, postgis...) can be data with coordinates referred to a spatial reference which can be different from the spatial reference of the map. This allow mapserver to combine data coming from different source in a single map. If not declared, the LAYER inherits the PROJECTION of the map. So, if yo have data in a projection and you want to project them in another, all you have to do is correctly declare both PROJECTION section: in the MAP and in LAYER. obviously you must to set correctly the EXTENT and the UNIT of the MAP, according to the PROJECTION of MAP, otherwise you will obtain a wrong part of the map from the mapserver. e.g.: if you have a PROJECTION latlon wgs84 the extent of the entire world is -180 -90 180 90 and units is DD, if the projection is world mercator the extent is -2000 -2000 2000 2000 (from my experience!) and units is meters. ( If someone can explain me the difference from world mercator and google mercator, and more generally can explain the parameters of proj4, I'll be eternally grateful! ) Hope this help pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Lun, Ottobre 27, 2008 12:46, Rahkonen Jukka wrote: Hi, Have you double-checked that your map extent correspods with the map projection? Or if you could send your whole mapfile I am pretty sure that you will get a final answer to your problem. -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Puolesta Monier Clement Lähetetty: 27. lokakuuta 2008 13:39 Vastaanottaja: 'Pietro Giannini'; mapserver-users@lists.osgeo.org Aihe: RE: [mapserver-users] projection = geographer's pain Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you want to show the whole map. So you can overlay more data sources in different projection in a single map. Try to set the layer PROJECTION as init=epsg:4326. Let us know... ciao ... pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Ven, Ottobre 24, 2008 16:55, Monier Clement wrote: Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order to perfectly
Re: [mapserver-users] projection = geographer's pain
Monier Clement wrote: Hi, There is bigger than tiny difference in extents in epsg:4326 and in epsg:3785. The latter is using meters as an unit. I had a try with Finland polygon and here are the results: D:\TEMPogrinfo -summary Finland_WGS84.shp Finland_WGS84 Feature Count: 1 Extent: (19.648331, 59.804989) - (31.587299, 70.079422) D:\TEMPogr2ogr -f ESRI Shapefile -s_srs epsg:4326 -t_srs epsg:900913 Finland_ Spherical.shp Finland_WGS84.shp D:\TEMPogrinfo -summary Finland_Spherical.shp Finland_Spherical Feature Count: 1 Extent: (2187242.167179, 8356448.200347) - (3516282.078834, 11094615.004724) -Jukka- Hi, I got the map extent from shpinfo. Beside, I know that there should only be a tiny difference between coordinates in latlon-wgs84 (data proj) and web spherical mercator (map proj). You'll find the whole test-case files as attachement. Here's the command line to get the map : C:\ms4w\tools\mapserv\shp2img -m C:\ms4w\apps\gmap\htdocs\test.map -o test.png -l layer1 -i agga Thanks Clément -Message d'origine- De : Rahkonen Jukka [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 12:46 À : Monier Clement; mapserver-users@lists.osgeo.org Objet : VS: [mapserver-users] projection = geographer's pain Hi, Have you double-checked that your map extent correspods with the map projection? Or if you could send your whole mapfile I am pretty sure that you will get a final answer to your problem. -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Puolesta Monier Clement Lähetetty: 27. lokakuuta 2008 13:39 Vastaanottaja: 'Pietro Giannini'; mapserver-users@lists.osgeo.org Aihe: RE: [mapserver-users] projection = geographer's pain Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you want to show the whole map. So you can overlay more data sources in different projection in a single map. Try to set the layer PROJECTION as init=epsg:4326. Let us know... ciao ... pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Ven, Ottobre 24, 2008 16:55, Monier Clement wrote: Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order to perfectly overlay the GoogleMaps tile images (for the moment, my maps are slightly shifted north.) I've added this string at the end of the file epsg in /ms4w/proj/nad : 3785 +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +towgs84=0,0,0,0,0,0,0 +units=m [EMAIL PROTECTED] +no_defs But I don't know how to modify my request and mapfile in order to get the correct map. I've tried many combinations so far but with no success until now. Do I have to change
RE: [mapserver-users] projection = geographer's pain
Of course ! You're right, that's why it didn't work. The bbox/extent should be in the same projection than the output system. Thanks for all Jukka Pietro ! I'll now try to figure out why GoogleMaps supplies some PixelToLongLat function to their Tile Overlay system, if longlat don't fit their actual projection system ! Clément -Message d'origine- De : Rahkonen Jukka [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 15:19 À : Monier Clement; mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain Monier Clement wrote: Hi, There is bigger than tiny difference in extents in epsg:4326 and in epsg:3785. The latter is using meters as an unit. I had a try with Finland polygon and here are the results: D:\TEMPogrinfo -summary Finland_WGS84.shp Finland_WGS84 Feature Count: 1 Extent: (19.648331, 59.804989) - (31.587299, 70.079422) D:\TEMPogr2ogr -f ESRI Shapefile -s_srs epsg:4326 -t_srs epsg:900913 Finland_ Spherical.shp Finland_WGS84.shp D:\TEMPogrinfo -summary Finland_Spherical.shp Finland_Spherical Feature Count: 1 Extent: (2187242.167179, 8356448.200347) - (3516282.078834, 11094615.004724) -Jukka- Hi, I got the map extent from shpinfo. Beside, I know that there should only be a tiny difference between coordinates in latlon-wgs84 (data proj) and web spherical mercator (map proj). You'll find the whole test-case files as attachement. Here's the command line to get the map : C:\ms4w\tools\mapserv\shp2img -m C:\ms4w\apps\gmap\htdocs\test.map -o test.png -l layer1 -i agga Thanks Clément -Message d'origine- De : Rahkonen Jukka [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 12:46 À : Monier Clement; mapserver-users@lists.osgeo.org Objet : VS: [mapserver-users] projection = geographer's pain Hi, Have you double-checked that your map extent correspods with the map projection? Or if you could send your whole mapfile I am pretty sure that you will get a final answer to your problem. -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Puolesta Monier Clement Lähetetty: 27. lokakuuta 2008 13:39 Vastaanottaja: 'Pietro Giannini'; mapserver-users@lists.osgeo.org Aihe: RE: [mapserver-users] projection = geographer's pain Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you want to show the whole map. So you can overlay more data sources in different projection in a single map. Try to set the layer PROJECTION as init=epsg:4326. Let us know... ciao ... pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Ven, Ottobre 24, 2008 16:55, Monier Clement wrote: Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order
Re: [mapserver-users] projection = geographer's pain
Hi Monier, My understanding of how this works is as follows. Assuming your data is in epsg:4326, and you wish to display it in epsg:3785: 1) Your LAYER needs to reflect epsg:4326. PROJECTION init=epsg:4326 END 2) Your layer also needs to have a wms_srs parameter in the METADATA section to allow for the layer to be requested in epsg:3785, ie METADATA wms_srs EPSG:4326 EPSG:3785 wms_namecounties wms_server_version 1.1.1 wms_format image/png wms_onlineresource http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/states/states.map; END 3) Your request to Mapserver needs to define the extents of the image you want , *in the units of the projection. *So a valid request for the layer above would be: http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/states/state.maphttp://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/test/test.map layers=counties srs=EPSG%3A3785 version=1.1.1 bbox=-20037508.34%2C-20037508.34%2C-10018754.1704%2C-10018754.1704 service=WMS width=256 styles= format=image%2Fpng request=GetMap height=25 Hope that helps, Roger -- Monier Clement wrote: Hi, There is bigger than tiny difference in extents in epsg:4326 and in epsg:3785. The latter is using meters as an unit. I had a try with Finland polygon and here are the results: D:\TEMPogrinfo -summary Finland_WGS84.shp Finland_WGS84 Feature Count: 1 Extent: (19.648331, 59.804989) - (31.587299, 70.079422) D:\TEMPogr2ogr -f ESRI Shapefile -s_srs epsg:4326 -t_srs epsg:900913 Finland_ Spherical.shp Finland_WGS84.shp D:\TEMPogrinfo -summary Finland_Spherical.shp Finland_Spherical Feature Count: 1 Extent: (2187242.167179, 8356448.200347) - (3516282.078834, 11094615.004724) -Jukka- Hi, I got the map extent from shpinfo. Beside, I know that there should only be a tiny difference between coordinates in latlon-wgs84 (data proj) and web spherical mercator (map proj). You'll find the whole test-case files as attachement. Here's the command line to get the map : C:\ms4w\tools\mapserv\shp2img -m C:\ms4w\apps\gmap\htdocs\test.map -o test.png -l layer1 -i agga Thanks Clément -Message d'origine- De : Rahkonen Jukka [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 12:46 À : Monier Clement; mapserver-users@lists.osgeo.org Objet : VS: [mapserver-users] projection = geographer's pain Hi, Have you double-checked that your map extent correspods with the map projection? Or if you could send your whole mapfile I am pretty sure that you will get a final answer to your problem. -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Puolesta Monier Clement Lähetetty: 27. lokakuuta 2008 13:39 Vastaanottaja: 'Pietro Giannini'; mapserver-users@lists.osgeo.org Aihe: RE: [mapserver-users] projection = geographer's pain Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you
RE: [mapserver-users] projection = geographer's pain
Youre right. I finally got a correct map by following your advices. Thanks a lot. _ De : Roger André [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 17:14 À : Monier Clement Cc : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain Hi Monier, My understanding of how this works is as follows. Assuming your data is in epsg:4326, and you wish to display it in epsg:3785: 1) Your LAYER needs to reflect epsg:4326. PROJECTION init=epsg:4326 END 2) Your layer also needs to have a wms_srs parameter in the METADATA section to allow for the layer to be requested in epsg:3785, ie METADATA wms_srs EPSG:4326 EPSG:3785 wms_namecounties wms_server_version 1.1.1 wms_format image/png wms_onlineresource http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/states/states.map http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/states/states.map; END 3) Your request to Mapserver needs to define the extents of the image you want , in the units of the projection. So a valid request for the layer above would be: http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/states/state.map http://localhost/cgi-bin/mapserv?map=/var/www/mapfiles/test/test.map layers=counties srs=EPSG%3A3785 version=1.1.1 bbox=-20037508.34%2C- 20037508.34%2C-10018754.1704%2C-10018754.1704 service=WMS width=256 styles= format=image%2Fpng request=GetMap height=25 Hope that helps, Roger -- Monier Clement wrote: Hi, There is bigger than tiny difference in extents in epsg:4326 and in epsg:3785. The latter is using meters as an unit. I had a try with Finland polygon and here are the results: D:\TEMPogrinfo -summary Finland_WGS84.shp Finland_WGS84 Feature Count: 1 Extent: (19.648331, 59.804989) - (31.587299, 70.079422) D:\TEMPogr2ogr -f ESRI Shapefile -s_srs epsg:4326 -t_srs epsg:900913 Finland_ Spherical.shp Finland_WGS84.shp D:\TEMPogrinfo -summary Finland_Spherical.shp Finland_Spherical Feature Count: 1 Extent: (2187242.167179, 8356448.200347) - (3516282.078834, 11094615.004724) -Jukka- Hi, I got the map extent from shpinfo. Beside, I know that there should only be a tiny difference between coordinates in latlon-wgs84 (data proj) and web spherical mercator (map proj). You'll find the whole test-case files as attachement. Here's the command line to get the map : C:\ms4w\tools\mapserv\shp2img -m C:\ms4w\apps\gmap\htdocs\test.map -o test.png -l layer1 -i agga Thanks Clément -Message d'origine- De : Rahkonen Jukka [mailto:[EMAIL PROTECTED] Envoyé : lundi 27 octobre 2008 12:46 À : Monier Clement; mapserver-users@lists.osgeo.org Objet : VS: [mapserver-users] projection = geographer's pain Hi, Have you double-checked that your map extent correspods with the map projection? Or if you could send your whole mapfile I am pretty sure that you will get a final answer to your problem. -Jukka Rahkonen- -Alkuperäinen viesti- Lähettäjä: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Puolesta Monier Clement Lähetetty: 27. lokakuuta 2008 13:39 Vastaanottaja: 'Pietro Giannini'; mapserver-users@lists.osgeo.org Aihe: RE: [mapserver-users] projection = geographer's pain Thanks for your answers Roger Pietro. I've followed your advice by trying these 4 test-cases : 1) Map proj set to : init=epsg:3785 (web spherical Mercator, manually added into espg file) Layer proj set to : init=epsg:4326 (latlon wgs84, proj system of my shapefiles) = got a blank map 2) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:4326 = got a map 3) Map projection set to : init=epsg:3785 Layer projection set to : init=epsg:3785 = got the same map as 2) 4) Map projection set to : init=epsg:4326 Layer projection set to : init=epsg:3785 = got a blank map I've also tried with another well-known existing epsg proj-system (instead of the manually-added 3785 code), but got the same results. I've made other attempts by replacing init=3785 by full description proj-string like +proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs no_defs or +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m [EMAIL PROTECTED] no_defs But it didn't change anything... It seems that : - a map is drawn only if the map's and layer's proj-systems are the same. - the output projection is always overridden by the shapefile system, no re-projection is done anyway. Let me know if you have any further leads to solve this issue. Thanks for your help Clément -Message d'origine- De : [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] De la part de Pietro Giannini Envoyé : vendredi 24 octobre 2008 21:40 À : mapserver-users@lists.osgeo.org Objet : Re: [mapserver-users] projection = geographer's pain I can confirm
[mapserver-users] projection = geographer's pain
Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order to perfectly overlay the GoogleMaps tile images (for the moment, my maps are slightly shifted north.) I've added this string at the end of the file epsg in /ms4w/proj/nad : 3785 +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +towgs84=0,0,0,0,0,0,0 +units=m [EMAIL PROTECTED] +no_defs But I don't know how to modify my request and mapfile in order to get the correct map. I've tried many combinations so far but with no success until now. Do I have to change the projection system of my shapefiles ? Is MapServer able to change projection between input and output ? Request : SRS=epsg:3785 MapFile : [Map section] METADATA wms_srs EPSG:4326 EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END [Layer section] METADATA wms_srs EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END With these settings, the pictures I got from MapServer are still shifted. Thanks for your help Clement ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] projection = geographer's pain
Hi Clement, Looking at the info you provided, I think the problem is here in your MAPFILE PROJECTION init=epsg:3785 # is this correct ? END I believe this should be set to init=epsg:4326 in order to define the projection of the shapefile. Then when the request is made to display the data in epsg:3785, the system will know how to calculate the reprojection. Best wishes, Roger -- ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
Re: [mapserver-users] projection = geographer's pain
I can confirm that projection is often a pain! However, the problem may be in the projection of the layer. The PROJECTION section in a layer declare the projection of the data source of this layer, while the PROJECTION on the map level is the projection wich you want to show the whole map. So you can overlay more data sources in different projection in a single map. Try to set the layer PROJECTION as init=epsg:4326. Let us know... ciao ... pg -- Pietro Giannini Bytewise srl - Area GIS 41°50'38.58N 12°29'13.39E On Ven, Ottobre 24, 2008 16:55, Monier Clement wrote: Hi, I'm running MS4W v2.2.8 (including MapServer 5.2) on windows. My datasource is shapefiles with WGS84 projection (epsg:4326). I would like MapServer to render these data into a Web (spherical) Mercator projected map (epsg:3785) in order to perfectly overlay the GoogleMaps tile images (for the moment, my maps are slightly shifted north.) I've added this string at the end of the file epsg in /ms4w/proj/nad : 3785 +proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +towgs84=0,0,0,0,0,0,0 +units=m [EMAIL PROTECTED] +no_defs But I don't know how to modify my request and mapfile in order to get the correct map. I've tried many combinations so far but with no success until now. Do I have to change the projection system of my shapefiles ? Is MapServer able to change projection between input and output ? Request : SRS=epsg:3785 MapFile : [Map section] METADATA wms_srs EPSG:4326 EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END [Layer section] METADATA wms_srs EPSG:3785 # is this correct ? END PROJECTION init=epsg:3785 # is this correct ? END With these settings, the pictures I got from MapServer are still shifted. Thanks for your help Clement ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users ___ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users
