Resurrecting an old thread I know but with the NSPD Open data also being available allowing Northern Ireland to be generated and having access to an otherwise idle 64bit server I've taken the opportunity to revisit this, and have successfully created the shapefiles (it only took the server 12 days to generate the blighters - it managed to generate Z16 tiles for the whole of Europe and Z18 for the British Isles in just 36 hours - meh!) but now have one more obstacle to overcome...
The Veroni thingy obviously generates the tiles so they butt up against one another which works perfectly here in the landlocked East Midlands, but goes somewhat wrong in coastal areas (Fig 1). My thought here is that the "World Boundaries" shape file can be used to trim the coastal boundaries to be locked to land so that the map looks "nice" (i.e. postcodes don't end up in the sea save for a little overlap on beaches) - Indeed if you add the World Boundaries file to Quantum GIS and use the "Clip Tool" you end up with what visually looks correct ( Fig. 3) but if you then hide the World Boundaries file the problem becomes obvious (Fig 2.) What I want to know, is it possible to trim the postcode shapes so that nothing outside another set of shapes (i.e. the British Isles landmass) is included, but instead of leaving gaps the postcode shapes (e.g. FY3 1) are adjusted so that the line runs along the coast line? i.e. I would be left with something visually the same as Fig. 3 but with the coastlines part of the NNXX-X shapefile layer, and more specifically the correct polygon (e.g. the FY3 1 polygon). Kev Fig 1 - Postcode areas in south west Lancashire and the north Wales coast (green = NNXX-X shapefile, blackline and dotted area uses the worldboundaries file) http://kjs.me.uk/3rdparty/osm/SouthWestLancs-NNXX-X.png Fig 2 - After using Quantum GIS's "Clip" tool - http://kjs.me.uk/3rdparty/osm/SouthWestLancs-NNXX-X_trimmed.png Fig 3 - After adding the "World Boundaries" back on. - SouthWestLancs-NNXX-X_trimmed_withwb.png *Open Street Map data licenced under the Creative Commons Attribution-Share Alike 2.0 license <http://creativecommons.org/licenses/by-sa/2.0/> by the OpenStreetMap <http://openstreetmap.org/>* project and its contributors. *Maps contain Ordnance Survey OpenData<http://www.ordnancesurvey.co.uk/oswebsite/opendata/>© Crown copyright and database right 2010. * *Postcode data in Great Britain is provided by Code-Point Open which contains Royal Mail data © Royal Mail copyright and database right 2010.* *Postcode data in Northern Ireland is from the NSPD Open<http://www.ons.gov.uk/about-statistics/geography/products/geog-products-postcode/nspd/>which contains National Statistics data © Crown copyright and database right 2010. * On Fri, Apr 30, 2010 at 12:30, Kev js1982 <o...@kevswindells.eu> wrote: > Hi Dave, > > Thanks for providing the shapefiles for download - they did the job nicely. > > One thing I have noticed (which also afflicts random.dev.openstreetmap.org) > is that a few postcode area/districts are missing - namely > > FY2 - (North Shore) Blackpool, Lancs > PE11 - Spalding, Lincs > PL17 - Callington, Cornwall > > Using the code point download (which I got via the MySociety mirror) shows > that these postcodes do exist. > > Also one of the AB ones (12 or 21 IIRC) for some reason includes parts of > Éire, Spain, Portugal and atlantic; while HS includes Reykjavik > > Just thought you'd like to know there is a possible error with the > conversion process. > > Nice work though - been after a postcode map for a while, and to go from an > A5 diagram to full "google maps" goodness in one swoop is awesome! > > Regards > > Kev Swindells. > > > On Mon, Apr 26, 2010 at 5:29 PM, Dave Stubbs <d...@randomjunk.co.uk>wrote: > >> On Mon, Apr 26, 2010 at 5:15 PM, Kev js1982 <o...@kevswindells.eu> wrote: >> > On Mon, Apr 26, 2010 at 5:00 PM, Kev js1982 <o...@kevswindells.eu> >> wrote: >> >> >> >> Thanks for that Dave - really useful. >> >> >> >> One question though - which prj string/file do I need for these? >> >> >> > >> > Answering my own question - looks to be Google Mercator. >> > >> > http://spatialreference.org/ref/sr-org/6627/ >> > >> > Kev Swindells >> > >> > >> >> Actually, for some obscure historical reason it's projected into >> "+proj=merc" which is srs 3395. >> >> Close to 900913, but not quite the same -- my mapnik stylesheet is >> then set to reproject to google mercator for the tile generation. >> >> Dave >> > >
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