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Launching bestofosm.org

7.07.2009 | Jochen Topf

The OpenStreetMap community has collected an awesome amount of data. There are many places around the world where the map shows incredible detail and we come back again and again to those places when we are showing people what OSM has accomplished. But we always had to remember where all those great places are. So we created the new web site bestofosm.org where we have put markers on the map showing all those great places. You can click on any of those markers and see a popup with information about the place. If you click on the thumbnail in those popups, the map will zoom to the place and even switch the base map to the one showing the best view of this feature.

We hope that this map can work as a sort of showcase for OSM. A place you can send your grandma to if you want to show her the power of OSM.  We intend to keep adding to this map and we’d love to hear what your favourite places are.

We have four kinds of entries: Places mapped with details above and beyond the call of duty are shown with a yellow star. A magnifying glass is shown for places that have played some role in OSM history (like the Isle of Wight where the first mapping party took place). Importing data from other data sources becomes more and more important for OSM. So we show some of those places with an arrow symbol. And finally there are just some interesting places around the world that OSM has good maps for which we show with an “earth” icon.

The slippy map was created with OpenLayers, you are familiar with it from other OSM sites. The base maps are the standard OSM base maps (Mapnik, Tiles@Home), the ever popular OpenCycleMap, plus the Public Transport map from öpnvkarte.de (the last currently only has data for Europe). The data for the four icon overlays comes from four KML files (they are linked at the bottom of the page). Its pretty easy to tell OpenLayers to load KML files and make the content into icons and popups. We added some special XML elements to the KML files. They tell the application which base map and which zoom to switch to when you click on the thumbnail images. Other applications reading the KML files will just ignore those special elements.

As OSM itself, the KML overlays come under CC-BY-SA, you are welcome to take them, add them to your own website, or do other things with it. You are also welcome to take ideas and code from our Javascript files. For faster access all Javascript is minified, but if you remove the “-minified” from the names of the Javascript files, you’ll get the non-minified versions.

The site currently doesn’t work in Internet Explorer, but we didn’t want to delay the release until we have the time to debug it. If you have any idea how to fix the OpenLayers KML support for IE, please shout.

Public Transport Workshop

28.05.2009 | Jochen Topf

There are many questions around mapping public transport related things in OSM. Should stops be tagged on the traffic way (like the highway or railway) or next to it (say where the bus stop sign stands)? How can you tie together several platforms of one railway station? What is the relationship between a subway line, the platform where it stops and the subway entrance? How should bus lines or subway lines be tagged and what about different variants of the same line? There are many more questions like this. Upon invitation from Geofabrik some people from the German OpenStreetMap community met in Karlsruhe on May 16th 2009 to discuss these issues and make some progress. Twelve people attended this meeting, including Melchior Moos, the creator of the OSM public transport slippy map at www.öpnvkarte.de and Thomas Reincke from the public transport authority of Aachen. Of course Frederik Ramm and me were also present.

Sebastian Schwarz, a student at the Karlsruhe University of Applied Sciences, is currently doing his diploma thesis with Geofabrik on this topic. He looked into previous discussions in the OSM community as well as how other organisations have been modelling public transport data. In this workshop he presented his findings and his ideas for improvements. The discussion then ranged over many topics and I think we found good solutions for many problems. Of course many compromises needed to be done and the ideas we came up with are not the end of the discussion but just one further step. We had to keep current practice in mind and tried to make things as simple as possible but still allow the complex material to be tagged in a way useful for renderers and other uses of the data.

The main topics were:

  • Clear differentiation between infrastructure (the actual “hardware” like the rail tracks itself or the stops) and network information (like bus lines and subway lines) relating to this infrastructure
  • More consistent tagging of different types of transport (Why is it “halt” for trains but “bus_stop” for buses? Why is one placed usually on the rail itself, the other next to the street?)
  • Introduction of a new “public_transport” tag key
  • Clustering of stops into “stop areas” and “stop area groups” to model large train stations etc.
  • Clear differentiation between “stop positions” (where the vehicle stops), platforms (where people wait and enter the vehicles) and entrances (for instance for subways)
  • Differentiation between railway routes describing longer stretches of possibly named railways and the public transport lines using those railways

Much more detail is available on the following Wiki pages:

Once the information has stabilized somewhat we’ll move those pages to a more “official” location.

Feel free to leave comments on the talk pages. Or discuss on the transit mailing list.

Sebastian has also worked on the OSM Inspector and added five new views that show different aspects of public transport mapping in OSM:

  • Railway Infrastructure – Shows the different types of rails
  • Non-railway Infrastructure – All non-rail infrastructure such as bus guideways, escalators or taxis stands
  • Ferries – Shows ferry lines and terminals
  • Stops – Shows all kinds of stops including stop position, accesses (such as platforms) and stop areas
  • Network – Shows public transport lines

Suggestions on how to improve those views are welcome.

Die 2., überarbeitete und erweiterte Auflage unseres Buches “OpenStreetMap – Die freie Weltkarte nutzen und mitgestalten” ist fertig und ab sofort erhältlich.

Für die Neuauflage haben wir nahezu alle Kapitel überarbeitet und Bilder aktualisiert. Sieben Kapitel sind neu hinzugekommen, viele wurden erweitert. Insgesamt ist der Umfang des Buches um 64 Seiten angewachsen – von 288 Seiten bei der ersten Auflage auf nun 352 Seiten, 32 davon in Farbe wie schon in der 1. Auflage.

Weitere Infos unter www.openstreetmap.info.

Die wichtigsten Änderungen:

  • Aktualisierung des OSM-Datenformates und der API für Version 0.6
  • Neues Kapitel zum Editor Merkaartor
  • Neues Kapitel zum Renderer Kosmos
  • Viele Erweiterungen und Aktualisierungen bei der Erklärung der Map Features
  • Neues Kapitel zu fortgeschrittenem Tagging mit Erklärungen zu Adressen/Hausnummern, Routen, u.v.m.
  • Neues Kapitel zu Hilfsprogrammen für Mapper: Data View, Data Browser, OSM Inspector, ITO OSM Mapper und Tagwatch
  • Umfangreiche Aktualisierungen in den Kapiteln zu Mapnik, Osmosis, Navigation und mobile Nutzung und zu den APIs
  • Neues Kapitel “Editieren für Fortgeschrittene”
  • Vollständig überarbeitetes Kapitel zum Import und Export von OSM-Daten

Geofabrik Tools Revamped

5.02.2009 | Frederik Ramm


We have added a slippy map and a map comparison view to our tools page. Yes, we know, there are some of these around already, but ours have received a lot of love in the finer detail.

The slippy map, for example, has a map grid layer that clearly shows tile coordinates and boundaries on all zoom levels, making it easy to spot rendering artifacts at tile boundaries. You can also choose to see not only the mouse cursor position, but also the current extent of the map view in degrees. The map also offers quick links to a series of other OpenStreetMap services – and when you switch from our map to, say, the map display at openstreetmap.org, the viewport will of course be retained.

The map comparison tool offers a side-by-side full-screen comparison of any two map sources, and also has a slaved cross-hair pointer for exact location of detail.

All Geofabrik tools are now linked through a drop-down in the top-right corner so that you can easily switch from the map view to the Inspector or the map comparison page – and back again – without having to zoom to the same location all the time.

We have also polished the entry page, so head over there and give it a test drive!

Oberpfalz macht Fortschritte

27.12.2008 | Frederik Ramm

(This posting refers to a high-profile, ongoing tracing activity in Germany where OSM was granted access to official aerial imagery. The remainder of the posting is in German only.)

Das bayerische Landesamt für Vermessung und Geoinformation hat OpenStreetMap Mitte Dezember Luftbilder für das Gebiet der Oberpfalz zur Verfügung gestellt und das Abdigitalisieren explizit erlaubt (Wiki-Seite). Die Hauptarbeit dabei wird von der Community getan; die Geofabrik stellt einen WMS und Serverplatz für die Bilddaten bereit und hat eine spezielle OSM Inspector-Ansicht eingerichtet, die alle Objekte verzeichnet, deren Quellenangabe auf diese Luftbilder verweist.

Eine statistische Auswertung der vorliegenden Daten zeigt deutliche Fortschritte (die Auswertung basiert auf einer Zählung der Straßenkilometer der jeweiligen Straßenklassen):

Das südlich von der Oberpfalz liegende, gleich große “Vergleichsgebiet”, das wir zu statisischen Zwecken mitbeobachten, zeigt kaum Entwicklung:

Auch in der Anzahl unterschiedlicher Benutzer, die im Gebiet aktiv sind, und in der Gesamtzahl der Nodes in den OSM-Daten der jeweiligen Region, zeigt sich die deutliche Wirkung der nun verfügbaren Luftbilder: