Every now and then, a mapping trip is not as successful as intended. And so was today’s. Here’s some C code describing my feelings :) :

Some code
Every now and then, a mapping trip is not as successful as intended. And so was today’s. Here’s some C code describing my feelings :) :

Some code
My recent changes are more or less political. As always when it comes to presets, I will be accused to abuse my position as a software developer to influence the tagging done by mappers.
In the openstreetmap database, we have footway, cycleway and bridleway values for the highway tag for a very long time now. As they were not really sufficient to map trails in the woods, hills, or mountains, paths have been introduced back in 2007 to circumvent the limitations. During the introduction, it has been suggested that footways, cycleways and bridleways should be abandoned in favour of paths with some additional attributes. As many people objected, paths have been introduced and the other types are still “valid”.
This leads to the current situation where similar things are mapped differently. For example, a footway is tagged as
highway=footway
If bikes are allowed, a valid tagging scheme reads as
highway=footway
bicycle=yes
Unfortunately, this scheme does not really allow to map combined foot- and cycleways (as often found in germany). Thus some mappers use
highway=path
foot=designated
bicycle=designated
for such purposes.
As a consequence, we see
highway=path
foot=designated
as synonymous to
highway=footway
The three time-honoured tags still are very convenient to use, while the path tag combined with some additional tags is the more flexible one. I have no clear opinion on that matter, but I tend to sense that a single tagging scheme would be better when it comes to consumers (like renderers) of our data. If our editors were better and capable of hiding all the tagging stuff completely, I would clearly propose to abandon the legacy tags in favour of the path tag. But our editors aren’t, and mappers still must be aware of tags.
Besides the abovementioned tags, we also use
highway=track
sometimes accompanied by some surface or tracktype tags:
highway=track
tracktype=grade2
surface=gravel
This tag is for agricultural or silvicultural roads. Obviously the meaning of tracks, bridleways, cycleways, footways and the various flavours of paths is at least ambiguous. This sometimes leads to frustration of mappers.
Given the current tagging scheme, I do it this way:
highway=cycleway (footway and bridleway respectively).highway=path foot=designated bicycle=designated.That’s surely not a perfect solution, but lets me map most things i find accurately.
I rearranged the presets in JOSM and am prepared for the usual bashing :) .
Tracks and paths have been reunified into one menu entry only, so the convenience menu shortcuts to the various types of tracks and paths are past. OTOH, I have introduced dedicated menu entries for combined foot and cycleways:
The types have been included as popup menus into the dialogs. Besides tracktypes and hiking scales, I also included mountainbike scales, while more special tags for mountain bikers can be used by including an existing set of externally maintained presets:
Obviously, the dialogs are completely overcrowded. We will not be able to stuff any and all tags that will develop in the future into JOSM. Be prepared that I will do some major cleanup work some day.
JOSM provides the capability to include presets from external sources. It is the perfect mechanism for a group of mappers to maintain a specialized set of presets. This way, »Special Interest« mappers like skiers, mountain bikers or seamen can feed menu entries they need directly into JOSM without polluting the default menu space of JOSM.
Some examples are available via JOSM’s wiki pages. There’s also a page how to create and use such presets.
Due to some talks I held at the LinuxTag, I received an electronic mail regarding this year’s call for papers. They are explicitely looking for papers about Openstreetmap, but I won’t write one and have no clue whether anyone already offered one. If you are interested, better ask them before writing the paper to avoid duplicated work.
As Daisy had even reached the Upper Rhine Plain, we had some snow for a couple of days. I used the occasion for three nice hiking trips in the Bienwald, mapping grade 4 and 5 tracks, hiking paths and, last but not least, the stream Heilbach and some drains alimenting it:
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Zum Jahreswechsel hat der KVV einerseits die Preise erhöht, andererseits neue Produkte eingeführt. Während ich sonst auch im Winter mit dem Rad ins Büro fahre, verkneife ich mir das im Moment ob des winterlichen Wetters. Nachdem ich eher selten vor 9:30h im Büro bin, habe ich mir heute die neue 9-Uhr-Monatskarte des KVV besorgt.
Beim Kauf wird das aktuelle Datum aufgestempelt. Die Karte ist ab dann einen Monat lang gültig¹. Die Karte gibt es für das Gesamtnetz für 52€ und für drei Waben für 37€.
Auf der Karte trägt man vor Fahrtantritt den Namen des Inhabers und im Falle der 3-Waben-Karte zwei Orte ein. Die Karte ist zwar für drei Waben gültig, allerdings muss man sich entscheiden, welche drei Waben das sein sollen.
Das Stadtgebiet Karlsruhe umfasst ob seiner Ausdehnung (bekanntlich) zwei Waben. Wohnt man also in Karlsruhe, kann man noch bis in eine Nachbarwabe (wie etwa Wörth) fahren. Wohnt und arbeitet man in Karlsruhe, kann bzw. muss man sich für eine der Nachbarwaben entscheiden, die man vielleicht doch gelegentlich mal anfahren will.
Für meine Zwecke ist die Karte genau richtig. Bisher hatte ich den KVV eher gemieden – wenn es das Wetter zuließ, bin ich mit dem Rad gefahren und ansonsten auch sehr oft einfach gelaufen, weil sowohl eine Monatskarte als auch eine Viererkarte für die paar Haltestellen, die ich ins Büro fahre, schlicht zu teuer war. Mit der 9-Uhr-Monatskarte hat es der KVV zumindest in den Wintermonaten geschafft, mich dort abzuholen, wo ich stehe. Ich sollte aber folgerichtig an den Tagen, an denen ich doch mal um 7h ins Büro fahre, aufpassen, eine Einzelfahrkarte zu lösen :) .
¹ Montags bis Freitags 9h bis 5h, Samstags, Sonn- und Feiertags ganztägig und bis 5h des Folgetages. Gilt bis zum gleichen Tag des Folgemonats, oder sogar bis zum darauffolgenden Werktag, falls es sich um einen Samstag, Sonn- oder Feiertag handelte.
The core of my home studio consist of a Notebook and a firewire mixing console. Unfortunately, Flash used my notebook speakers for audio output instead of the firewire device. There are several workaround setups to circumvent this, but most of them are at least a bit cumbersome.
Thorben Hohn fortunately wrote a library which provides an elegant solution. Here’s what to do:
mkdir libflashsupport-jack
cd libflashsupport-jack
git clone git://repo.or.cz/libflashsupport-jack.git
cd libflashsupport-jack
sh bootstrap.sh
make
make -n install
sudo make install
Restart firefox and listen to your favourite music video on Youtube (Zansa and Bimoya) via jackd – what a joy! All credits to Thorben for the excellent work.
A couple of days back, I converted the SRTM dataset into tiles containing OSM contour lines. Meanwhile the tiles are available online. This service is provided by the Stuttgart University of applied Sciences, thanks to the support of Dr. Franz-Josef Behr.
I hope the data is useful for some community work, e.g. tile rendering for slippy maps or rendering contour lines into viewports of mobile devices. If you create publicy available stuff from the data, please drop me a line.
The data of openstreetmap is stored in a relatively simple manner. Basically, we have three base datatypes:
node id='12345' lat='48.9955' lon='8.3948'.way id='23456' nd ref='12345' nd ref='12346'.relation id='34567' member type='node' ref='12345' role='' member type='way' ref='23456' role=''.Simple plain text Tags are used to determine what kind of map feature a node, way or relation represents. A tag consists of a key-value-combination like amenity=bench, natural=water, highway=residential or route=ski. Mappers are invited to invent new tags whenever necessary. This freedom plays an important role concerning the success of the project.
Prior to API 0.5, we had Segments. A segment connected two nodes. First, tags have been applied directly to segments. Then, ways have been introduced which joined segments together. Since then, the tags have been applied to the ways instead of the segments. Segments caused some trouble (namely “unordered segments” for the old dogs) and have been abandoned during the introduction of API 0.5.
So nowadays we have nodes, ways, relations and tags. Easy, isn’t it? True for nodes, ways and tags. Not true for relations, though. Relations are difficult to create and edit, because they most often have no direct graphical representation in the editors. More or less they appear a bit flange-mounted on top of nodes and ways. Nevertheless they allow us to map things that otherwise would be difficult or impossible to model.
In addition to some prior mapping of black forest ski runs, I’ve been on-site again last sunday. Meanwhile, Langläufer contacted me due to my mapping activities. I’ve now tagged the route relations according to the tags he currently renders. Here’s the result as seen on his map:
The map is similar like Openpistemap or the Hiking and horseback riding map created by Nop. Some collaboration or mashups would be great.
During the holidays, I continued mapping Kaufungen (and Helsa), where some residential areas were still missing. I was surprised that no other mapper found it during last year’s course:
There are still some details missing, namely streets south of the station (thus the marker). If I have good luck, those will still be missing next X-mas :) .
I do not operate a car of my own. Instead, I’m a customer of a local car sharing provider. For the X-mas family meeting, I rent a less than two years old car.