All, reame in demo/c++ suggests to read rundemo.py to get more commented code. Comparing rundemo.py and rundemo.cpp i've found box coordinates are different! why? rundemo.cpp: 246 m.zoom_to_box(box2d<double>(1405120.04127408,-247003.813399447, 247 1706357.31328276,-25098.593149577)); rundemo.py: 322 # Set the initial extent of the map in 'master' spherical Mercator projection 323 m.zoom_to_box(mapnik2.Box2d(-8024477.28459,5445190.38849,-7381388.20071,5662941.44855))
I've searched around google for hours, still not able to render any area from the DB. :( I'm always more confused! Gianluca Gianks wrote: > > > M∡rtin Koppenhoefer wrote: >> >> 2011/10/3 Gianks <[email protected]>: >>> I've also looked at the Proj4 software and, always stading to what i've >>> understood, >>> it's a cli converter which accept args like: >>> +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 >>> +units=m >>> +no_defs >>> and convert from lat lon in the desired system. >>> >>> But again, not knowing the correct string to use with OSM is making me >>> unable to obtain the box coordinates. >> >> >> The string should be: "+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 +nadgrids=@null +no_defs >> +over" if you have your data imported in spherical mercator into your >> db (e.g. with osm2pgsql and the default projection option). >> >> cheers, >> Martin >> _______________________________________________ >> Mapnik-users mailing list >> [email protected] >> https://lists.berlios.de/mailman/listinfo/mapnik-users >> >> > > Martin, yes, i'm using the Italy only database downloaded from > planet.osm.org. > Since i'm restricteed to italy, i wish to represent the area between: 42N > 12E and 43N 13E > > I've started proj with your string, than i've converted coordinates as > this: > 42 12 > 4675418.61 1345708.41 > 43 13 > 4786738.10 1459732.27 > > I've changed the app code accordingly: > Map m(800,600, "+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 +nadgrids=@null +no_defs > +over"); > m.zoom_to_box(box2d<double>(4675418.61, 1345708.41, > 4786738.10, > 1459732.27 )); > > > STILL GETTING BLANK IMAGE! > > Here you can find the non working modified demo code: > http://pastie.org/2631400 SOURCE > > Please, can you give me hints about what i am doing wrong? > Does someone have a working mapnik + OSM data in Postgres code example? > > Thanks! > Gianluca > -- View this message in context: http://old.nabble.com/Mapnik-coordinates%2C-zoom_to_box-tp32576024p32581994.html Sent from the Mapnik - Users mailing list archive at Nabble.com. _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users
