As most of my readers will probably know Openstreetmap is in progress to change it’s licence to a less restrictive one (at least from a data users perspective). Fortunately this will likely remain the only Openstreetmap licence change in my livetime well at least the only invasive one.

Today the so called redaction bot finished its work leaving the database in a state where most of the data origins from people which approved the new licence.

The Place where I live (Karlsruhe/Germany) has been one of the places to be fully mapped at a fairly early state of the project.
And ss with the rest of Germany most of the stuff originates from crowdsourcing work.

This turned out to be a huge advantage compared to places likeSydneywhere quite a lot of data has been imported from sources which did partly not agree with the licence change and which looks quite messy now.

While Karlsruhe also looks quite bad on theredaction bot view of OSM Inspector it does not look that bad if you check the details.

The red stuff mainly originates from one mapper doing quite a lot of public transport stuff, which lost some details now here and there, but most parts of the map are still quite intact.

But after all this is mostly what I would have expected, so here comes what I did not expect at all:

Back in 2009 I mapped two long-distance cycle tracks and last sommer we mapped another one while I was cycling with Christoph.

So this evening I decided to repair these relations and based on the fact that every single one of them is roughly 150km long I expected that this would be a lot of work.

This proved to be completely wrong. I did have to fix next to nothing on any of the three relations. Only one licence change related fix in all of them!

So instead of fixing bugs caused by OSM licence change I spend my evening writing silly blog postings like this one 🙂

The usually so called shapefiles are typically not files but a couple of them with different extensions. Thus it is not very convenient to rename them.

Fortunately a Unix Shell is a very powerful tool so here comes shpmv which is a simple bash shell function. Just put it in your .bashrc. It works fine regardless if an extension (e.g. .shp) is given or not.

function shpmv() {
  if [ $# -ne 2 ]; then
    echo "shpmv: rename shapefiles"
    echo "usage: shpmv  "
    return
  fi
  src="${1%.*}"
  tgt="${2%.*}"
  if ! [ -f $src.shp ]; then
    echo "$src.shp: file not found"   
    return  
  fi
  for f in $src.*; do
    ext="${f##*.}"      
    mv $f $tgt.$ext
  done  
}

When rendering maps people coming from a traditional GIS background tend to use Mapserver rather than Mapnik. I don’t know the reason for this, but it is probably just because Mapserver is quite mature and has been around for a long time while Mapnik is still relatively new.

I also did quite a few things using Mapserver in the past but mostly in the WMS and raster data area.

One thing Mapserver can do is rendering based on data values rather than just by predefined rules, which could be quite useful for river widths and the like. This was not possible in Mapnik at least not in Mapnik versions < 2.0.

Mapserver is scriptable in a couple of languages (not just Python) and this is why it has been relatively easy coding a new backend for Tirex although Perl is not quite my favourite scripting language. Of course this new backend is heavily based on the existing WMS backend.

So why did I do this? Well, last week I just stumbled upon the nice Topomap project which Max Berger is doing and unfortunately he map is limited to a very small area.

Hopefully I will be able to provide a map of this style for a couple of other areas real soon now. I’m especially interested in islands with good hiking options, the so called Wanderinseln in German.

I just commited the changes to the Openstreetmap SVN-repository in the hope that it might be useful for others as well.

BTW, Max is using TileCache which I could probably use as well. Probably someone can enlighten me about the pros and cons of Tirex vs. TileCache.

Seit einigen Monaten gibt es auf der deutschen OSM Homepage einen eigenen Kartenstil, der im Rahmen einer Bachelorarbeit an der HFT Stuttgart aus dem internationalen Stil entstanden ist. Dieser Stil versucht sich an die hierzulande in Karten üblichen Gepflogenheiten zu halten und trotzdem nicht allzuweit von der internationalen Variante abzuweichen.

Im Gegensatz zu einer Bachelorarbeit und einem Studium ist ein Kartenstil für ein solch dynamisches Projekt wie Openstreetmap aber niemals fertig.

Aus diesem Grund haben wir jetzt eine Arbeitsliste gegründet. Die Abonnenten dieser Liste möchten sich der Weiterentwicklung und Pflege dieses Kartenstils annehmen.

Insbesondere warten schon diverse Änderungen am internationalen Stil auf ihre Portierung.

Über weitere Mitstreiter, die mit der Mapnik Toolchain und Subversion umgehen können würden wir uns freuen.

Es geht bei der Liste ausdrücklich nicht um Diskussionen was man darstellen sollte und was nicht. Dafür gibt es talk-de und das Forum.

Was die Technik betrifft ist der Server leider sehr langsam und stellt derzeit auch nur Europa zur Verfügung. Das ändert sich hoffentlich bald wenn wir unseren eigenen Server bekommen.

Wenn jemand den Betreiber eines Rechenzentrums kennt der dem Openstreetmap Projekt etwas gutes tun möchte möge sich umgehend bei mir melden. Wir bräuchten etwa 3HE Platz in einem Serverschrank.

German Company Aerowest is providing Openstreetmap with high resolution Images.

Once again I have been doing most of the technical work which needed to be done behind the scenes. While wms.openstreetmap.de has been up and running for a few weeks now I still had to do some stuff to get the things going.

First of all I converted the mapscript from the older mod_python to the state of the art mod_wsgi. Furthermore the script has been extended to allow for individual copyright-watermarks based on mapfile entries. Tiles generated for Potlatch are now cached using the Apache Module mod_disk_cache.

The aerial image itself came as a raster image of 201 Gigapixels in the very good (in terms of image compression) but proprietary ECW-format. For legal reasons we are now using another format for actually serving the image (eating a huge 675 Gigabytes of disk-space) because the proprietary license of libecwj2 does not state very clearly if we are allowed to use it in our setup or not.

A few weeks ago I started to set up http://wms.openstreetmap.de to serve aerial images donated by various sources for Openstreetmap use. Currently the system holds data from german communities Lauf an der Pegnitz and Neunkirchen am Sand (thank you very much for donating the data!). It is designed to be extensible with additional data in an easy way. If anybody in the Openstreetmap community is looking for such a service just drop me a line.

The system is powered by Mapservers mapscript written in Python to allow for convenient URLs in JOSM’s WMS plugin. In addition to this I just added support for the Online Openstreetmap Editor Potlatch while learning how to use custom tile-servers with it by chance. This is done by converting tilenames in z/x/y format to the bounding boxes needed for WMS. An Apache mod_rewrite rule provides a virtual tile-URL in the syntax needed by Potlatch and allows for direct edit-links of the available areas now provided on http://wms.openstreetmap.de

The script itself will be released as free software and added to Openstreetmap SVN.

Finally I need to mention that the system is also running on one of the Servers sponsored by german webhosting company STRATO AG.