On 8/26/12 5:44 AM, klo uo wrote: > On Sun, Aug 26, 2012 at 12:18 AM, Jeff Whitaker <jsw...@fastmail.fm> wrote: >> Klo: The image in interpolated to the Basemap projection region. This is >> slow - the main reason to use the WMS is to avoid this by having it done on >> the server side. > All right, that's the right way anyway > > >> The trick is to figure out what the EPSG projection code is based on the >> Basemap projection info, and pass that information to the WMS server so it >> can do the interpolation. > Yes, and also to pass right `size` parameter as aspect ratio needs to be > correct > Do you want me to try to pair both projections (Basemap name and WKID > and WKT as they call it)?
Klo: Since epsg codes comprise a very small subset of possible Basemap projections, it may be better to just allow Basemap to accept an epsg kwarg. That keyword would be required in order to use a WMS to display a map background. This may be tricky though, since Basemap needs more information to define a map projection region than is provided by the epsg code. We may have to start with just a few supported epsg codes and then add more as necessary. I added a testwms.py example to my fork (https://github.com/jswhit/basemap.git) that shows how to use three different map projections (epsg codes). -Jeff -Jeff > > >> Here's an example for south polar stereographic: >> >> width = 12000.e3 >> plt.figure() >> basemap_url =\ >> "http://server.arcgisonline.com/ArcGIS/rest/services/ESRI_Imagery_World_2D/MapServer/export?\ >> bbox=%d,%d,%d,%d&\ >> bboxSR=3412&\ >> imageSR=3412&\ >> size=800,800&\ >> dpi=128&\ >> format=png32&\ >> f=image" % (-width/2,-width/2,width/2,width/2) >> m =\ >> Basemap(projection='stere',resolution='i',lon_0=0,lat_0=-90,lat_ts=-70,\ >> width=width,height=width,rsphere=(6378273,6356889.449)) >> m.imshow(plt.imread(urllib2.urlopen(basemap_url)),origin='upper') >> m.drawmeridians(np.arange(-180,180,30),labels=[0,0,0,1],color='y') >> m.drawparallels(np.arange(-80,-0,10),labels=[1,0,0,0],color='y') >> m.drawcoastlines() >> plt.show() >> > Looks beautifully :) > > As said later today I'll look at Nokia maps and then will try to look > for WMS servers. ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
