Hello list,
For my efforts mapping public transportation routes in Milan, I have up
to now relied on Öpnvkarte to look at the data I entered and
occasionally look up the best way to get around town.
In the meantime the situation has changed: Öpnvkarte hasn't been updated
since early September; a similar service at latlon.org has discontinued
coverage for Western Europe (they seem to have limited themselves to
Belorussia, Russia and maybe some of their neighbors) and the third
player in the field, OSM Transport, comes with disadvantages (slow to
load, slow to update, less "nice" to use and not open-source).
Couldn't we do something similar right on the OSM homepage, running on
OSM infrastructure?
The advantages would be:
- Easy switching between "normal" and "public transport" view (just a
matter of switching base layers)
- Only one URL to remember
- Uses most recent data (if directly connected to live OSM database)
- Standard OSM tools available (for instance, exporting the map as PDF)
- Could be a "killer app" for OSM (until now this information is
available only for single networks from their respective transport
companies, if at all; OSM would be the first to do this for the whole world)
Following the iterative approach with which OSM was and is being built,
here's how it could be implemented:
Step 1: Add the new map view
Create a new Mapnik style sheet with routes and numbers overlaid on it.
I would suggest the familiar Mapnik view but in black and white (at the
most I would color some landuses), possibly reducing the number of POIs
if the map gets too cluttered. All stop names would be shown; routes and
their numbers would be drawn in color on top of everything else. This
would preserve all information but make public transport data stand out.
This should be fairly easy, it would take a second Mapnik style sheet
and possibly some post-processing to render the routes. The database is
already there; all rendering-related effort I would expect to roughly
double as every tile would get rendered twice (once per style). Not sure
about the effort to run Mapnik with two different styles.
Step 2: Add stop information
Add a new overlay, which makes all stops clickable. Clicking on a stop
opens a bubble with information on it, such as name and lines stopping
there.
This would require some extra coding, but most of the work has been done
already (e.g. OpenStreetBugs, which has an overlay for clickable bugs).
Some extra post-processing will probably be needed on the data in order
to group nearby stops belonging together (take Munich's central station,
which consists of one light railway stop, two subway stops, three tram
stops and a couple of bus stops): that way the user just needs to click
the station and gets a popup with all the light railway, subway, tram
and bus lines. Öpnvkarte already does this, so it's not impossible.
Step 2a: Line sketches
In the popup for each stop, clicking the line number opens a new window
with a sketch of the line.
Probably easy play: Sketch Line from OSM Server Scripts [1] (example
[2]) already does an excellent job at this; just the choice of colors
may need some tweaking. The only problem is that the output is in SVG
format, which not all browsers out in the field handle well: we may need
to convert that into a bitmap on the fly.
Step 3: Extensions
Up to the imagination of the community: For example, if one day we add
routing to the OSM page, we could extend that to finding a public
transport connection.
Taking Milan as an example, step 2a would already put us ahead of what
Google has to offer today: Transit is not available for Milan yet, bus
stops are missing completely on the map, the location of subway stops is
approximate at best and the network data seems to be out of date.
Now here's the catch: While I am ready to contribute to such an effort,
I cannot do it alone - my knowledge of the OSM infrastructure is generic
at best. Is there anyone out there who:
- knows how to get started in order to get new items on the main OSM
page, in terms of both technology and who to talk to?
- is willing to participate in such an effort?
Any input is greatly appreciated.
Michael
[1] http://wiki.openstreetmap.org/wiki/OSM_Server_Side_Script
[2] http://78.46.81.38/api/sketch-line?network=SITAM&ref=19&style=padua
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