Recent diary entries
After participating in the Missing Maps in Antwerpen, I went to the one in The Netherlands yesterday. Big thanks to Philip for making this possible for me!
The people from MSF/AZG/DWB/Red Cross had 2 Tasks in mind for us.
A though one in Africa where we had to add natural wood and rivers, as those are the (breeding) habitat for tse-tse flies, which cause sleeping disease. The beginners using iD had to abandon that one, as it's impractical to zoom in far enough to work and still see the bigger picture. With JOSM one can draw a general contour of the wood at low zoom, then refine it by using the Improve Way Accuracy mode zoomed in a lot further. It's still a daunting task to get it right though. What can be considered wood/forest? How does one recognise wetlands?
The other task was in Haiti. It was not easy either. A densely populated area and MSF wants to know how many buildings there are. (It's explained better in the description...)
It peaked my interest for 2 reasons:
- They used a drone to create superior aerial imagery
- The Red Cross drove around with a smartphone used as a dashcam. The pictures were uploaded to Mapillary. Press that little play button and enjoy the ride.
This allows to go and have a look around and see what's actually there. The width and state of the road, the state of completion of the buildings and so on.
Coverage is more limited than what can be seen from above, but it's possible to read the name of a school and then it's clear as well that it is a school.
The great thing about Mapillary is that the barrier of entry to contribute yourself is a lot lower than say, fly a drone to create excellent imagery...
All you need is a smartphone with a descent camera and GPS. Bonus points if it has a electronic compass, but that information can also be gotten from the GPX track. (electronic bread crumbs trail of where you've been).
I've been doing this for Geofort, somewhat surprised that I was the first one to do it. We've also covered a good part of the way over to Geofort from Belgium. Interrupted between Brasschaat and Breda because of a drizzle.
Only It's so Funny did the same. I had expected to see all the roads to the geofort from all directions. Now I feel bad for not having mentioned it on the Meetup group beforehand. Mapillary still seems less known than I had expected. Hence this diary entry.
Let's give Google Streetview some competition and do them one better! There are so many places their survey cars can't reach! And hopefully one day, they decide to be even nicer than they claim to be and give us permission to look at their Streetview to improve Openstreetmap. One can always be optimistic :-)
In Finland they seem to think it's a good idea to also add the road signs themselves. I tend to agree with them, but trying to add them all, may not make sense, of course, as there are a gazillion of them.
There are no applications making use of this information, but for us it would enable double checking why some ways have certain tags.
In Finland they are also able to find where zones are 'leaking' and they report this back to the administrations, so it gets fixed.
So I'm not saying we should aim to map all of them, but I still want it to be possible and convenient to add those that have our interest.
So I've been working on the RoadSigns plugin to make sure it has data about the Belgian Road signs. The work is not done yet, but I think I was now able to add all the accompanying signs and all signs related to parking, of which there are surprisingly many! The way it works now, you'll have to remove the tags it adds, for those objects they don't apply to. I've made a few suggestions for improving the workflow, but it's unlikely those will be implemented anytime soon, except if I get my hands 'dirty' and do it myself...
So the effect of the sign remains on the ways, and the (Belgian) code for the sign itself remains on the new node you created before using the plugin.
If you don't check the tick box Traffic sign, that code won't be added and you don't have to remove any tags. The plugin then does what it was designed for, add the effect of the sign to the ways it applies to.
What I'm not sure of, since it was an enormous task that I gravely underestimated, is whether all the tags, that are applied as an effect are actually correct. So the plugin needs testing.
Or you can have a look at this wiki page, there may be obvious errors in it that jump out to you :-)
Using the plugin is a bit more convenient though, as you can actually see the signs, instead of those codes.
Oh, if you see that additional signs are missing from signs they can be next to, also report that please.
While looking at source code of JOSM plugins, I stumbled across the RoadSigns and the ScoutSigns plugins. ScoutSigns adds some source data added by people using Skobbler.
For each sign, it gives a litlle picture taken by that 'reporter'. When adding the effect of those signs on the road it applies to, I was wondering if it would be possible to map the sign itself.
At the moment the RoadSigns plugin doesn't support that yet. But that's what an old hand like me needs it for. I know the tags which get applied to the way, mostly by heart by now. But those codes which are different from country to country, can't be bothered to remember those.
So I was thinking it might be nice to be able to add a node next to the way, select it and select the way(s) it affects. Then click on the little extra icon on the top right of the Tags pane. Select a traffic sign and signs that accompany it. Then it should automagically do the right thing with both the ways and that isolated node next to the way.
I think it's needed to extend the xml format. I created an example here:
Now I'll have to get my hands dirty and start coding to make that happen, so I can hand a patch to the developer of the plugin.
But before doing that, I also want it to work for Belgian signs.
To do that, we also need icons.
They are here: http://wiki.openstreetmap.org/wiki/Road_signs_in_Belgium
Fortunately they are also on the German Wikipedia. I fetched all the SVG files as follows:
import wikipedia import urllib.request import re filenameRE = re.compile(r'http://upload.wikimedia.org/wikipedia/commons/.+/.+/Belgian_road_sign_(\w\d+(\w)*.svg)') wikipedia.set_lang('de') wp = wikipedia.page("Bildtafel_der_Verkehrszeichen_in_Belgien") print (dir(wp)) for url in wp.images: fn = filenameRE.match(url) if fn: fn = fn.group(1) print (url) print (fn) if fn: urllib.request.urlretrieve(url, fn)
Before that "import wikipedia" line works, you'll have to do pip install wikipedia where you installed Python
For the next part, of converting those SVG files to PNG, I tried to use Powershell, as I need to learn how to work with, but the syntax is horrid and I got disgusted.
So back to my trusted Python:
from glob import glob import subprocess for fn in glob('C:\data\RoadSigns\*.svg'): bn = fn.split('.').split('\\')[-1] print (bn) print(subprocess.check_output(['C:\data\Program Files (x86)\Inkscape\inkscape.exe', '-z', '-h 40', bn + '.svg', '-e ' + bn + '.png'], shell=True))
I took a while to figure all that out and get the syntax right, hopefully it's useful for somebody else, some day.
I went totally out of my comfort zone today. I was reviewing some pictures I had submitted to Mapillary and found one, I wanted to add right away to OSM. So I tried the link to edit it with iD. The first thing that's odd, is that the zoom level is far out and the location of the object is way off. (It ends up all the way to the right, under the vertical button bar). I'd have expected it to appear centered, zoom level 21.
The next thing that's annoying, is that the Mapillary layer is not switched on automatically, so I need to know iD to know where to go to switch it on. That's not entirely intuitive.
Anyway, time to try and create a Mapillary plugin for JOSM.
Then I wanted to upload what I just added. But I couldn't figure out how to add tags to the changeset. In version 2 I managed to add a source, but that ended up on the object. Now this scrawny tree already has 3 versions and none of those changesets have the source information I wanted to add to it.
Gedurende het voorjaar en de zomer van 2014, ontdekte ik een paar interessante plaatsen in Heverleebos en Meerdaalwoud ten zuiden van Leuven. Mijn interesse werd gewekt door een aantal houten standbeelden/sculpturen gemaakt van dode bomen. Ik had deze wel eens eerder opgemerkt, maar had er tot dan nooit veel aandacht aan besteed.
Toen ik er dan uiteindelijk toch eens wat meer over ging opzoeken, ben ik begonnen aan een Artikel over Ad Wouters op Wikipedia. Wist ik veel hoeveel tijd en energie daar zou gaan insteken! Ik was het natuurlijk aan mezelf verplicht om dat te gaan vertalen... En uiteraard had ik ook een kaartje nodig om het te illustreren. Dit heb ik gemaakt met behulp van Maperitive:
Deze kaart is enig in zijn soort. Er worden gegevens van het openbaar vervoer, haltes en routes (lichtblauw en roze) gecombineerd met knooppunten van het wandelknooppuntennetwerk (rood/oranje) en natuurlijk de OSM-data, plus de route die ik wilde beschrijven (blauw). Nog geen 10 jaar geleden was zoiets zelf maken simpelweg ondenkbaar.
En toen ontdekte ik Wikivoyage:
Het loont de moeite om beide taalversies te bekijken. De verschillen onderling zijn groot.
Op de Engelstalige Wikivoyage hebben ze een widget, waarop Openstreetmapdata wordt weergegeven. Het is mogelijk om te schakelen tussen lagen en er transparante lagen overheen te leggen, wat toelaat om de wandel- en fietsknooppuntennetwerken te tonen. Daarenboven is het mogelijk om klikbare POI's in de tekst te vermelden, die dan op de dynamische kaart worden weergegeven.
Bloed, zweet en tranen heeft het gekost om me aan alle regeltjes aan te passen en me in bochten te wringen om eraan te voldoen. 't was nogal een leerervaring, om het zacht uit te drukken. Elk project heeft z'n eigen eigenaardigheden, die natuurlijk totaal verschillend zijn van hoe het er bij OSM aan toe gaat en zelfs van de ene taalversie naar de andere zijn er verschillen.
Uiteindelijk ben ik wel tevreden met het resultaat, al weet ik niet of ik spoedig nog eens aan zo'n projectje zou durven beginnen. Al bij al voel ik me bij OSM toch nog het best in m'n vel.
During the spring and summer of 2014, I discovered some interesting places in the forest south of Leuven. My interest was peeked by some wooden statues/carvings made from dead trees. I had seen some of them before, but I hadn't really been paying attention, and they didn't register as a 'collection' until then.
When I did finally investigate further, it lead to the creation of an Article about Ad Wouters on Wikipedia. Of course, I needed to illustrate that with a map, so I created one with Maperitive:
This map is unique in that it combines information about the public transport stops and routes (light blue/pink) and the walking node network (red/orange) and, of course OSM data, together with the route I was describing (blue). Only 10 years ago it would have been impossible to even consider attempting to create such a work.
Subsequently I discovered Wikivoyage:
On Wikivoyage they have a widget, which displays Openstreetmap data. One can switch layers and add overlays, allowing to show the cycle and the walking node network as well, but more importantly one can mention POIs in the text and have them appear on that dynamic map
It took some learning and stumbling. Each of these projects has their own rules and intricacies, which are completely different from OSM, but they are also different among what I consider a family of projects and even from one language version to another. At times they almost drove me mad, but now I'm quite happy with the results. I'm not sure if I'll attempt something similar again any time soon though. Mapping for OSM has its own rewards.
Today I put template route relations for itineraries of De Lijn and TEC on Dropbox. Generating them takes 2 hours. And then another 2 hours when I noticed Python hadn't actually compressed them. I'll update them as fresh data from De Lijn and TEC comes in.
I also worked on a script which you can run after opening such a file in OSM.
(no sound was recorded and I still have to add subtitles to them, some day)
The script will download all the stops. They are not included in the files. Once the stops are downloaded the view zooms to their extent.
Then the script will use an Overpass Query to download all route relations with the same ref as identifier. At the moment all over Flanders. I hope I'll find a way to limit it to the bbox you just zoomed to.
For all the nodes on the way, Overpass will download all the nodes which are within 30 meters (and all the ways and relations they belong to).
Now you'll have to run the compare script again. I didn't figure out yet, how to make the script wait until the download completes, so it'll give an error message saying it didn't find the master_routes it was looking for.
When run again, after the download is complete with not objects selected, it'll compare the template routes with the already existing routes. It uses the master_route relations to match them. If the existing routes don't belong to a master_route yet, you'll have to use the template and add the matching existing routes manually. You can leave the template routes, they'll be removed from the master as we progress. Select all the existing and the template routes and close the master route. Now run the compare script again.
You'll end up with a relation which has some funny looking roles. Each letter-number (a0w1i3) combination represents as stop. Now it becomes easier to see which template belongs to which existing route.
Select 2 routes which belong together and press the button to select them in the general window.
Move the window with all the routes out of the way.
Use the other script, which will add ways to the route. At first this script only added the ways adjacent to the stops. At some point I was thinking: why not try to look at the other route relations. Buses tend to all use the same itineraries to get from one stop to the next.
In the mean time the script also copies tags and stops from the template to the existing route relation and it odbl=new. This has the effect that it's shown more prominently with help of MapCSS. Nothing to do with the license. That tag is only used, as it won't 'survive' during upload.
Also the template routes came in tagged with odbl=tttttt. This is what the script uses to identify them as templates.
I'll have to write some posts about how to set up JOSM to enable everybody to use those scripts, the MapCSS and add handy buttons for search and one click presets to the toolbar. One of these days...
People sometimes ask me: why add all these route relations to Openstreetmap, when De Lijn already has them as shape files?
For one thing, De Lijn cannot share them with us. A good example is the following:
If you click through to one of the other lines, change the url so it has &style=wuppertal once again at the end. Also keep in mind not each and every line is already mapped, although we're doing quite well in Oost-Vlaanderen.
Another example is a map I rendered where I'm combining the PT network (pink on the background), the walking nodes network (orange) and the route I wanted to talk about:
Only, say 10 years ago, creating such a map would have been an impossible endeavour. It's important for the explanation on this site:
To be able to show where the bus stops are and the walking node numbers are used in the directions, but not exactly used the way they were meant to be used... only to help point people in the right direction, instead of following them from node to node.
Incidentally you'll have to have a look at the Dutch version of the article to see the map used. The English version uses Openstreetmap too, but in a more dynamic way.
I attended a meeting of the Peruvian community on Saturday. Somebody showed us the capabilities of Mapillary. Of course, I'm hooked already.
Soon the parts of the city and surroudings I frequently visit will be visible on Mapillary.
I've been waiting for a long time for a way to link back to pictures I took during my surveys. Wikimedia Commons is no good for this, all the worthwhile pictures I uploaded there got nominated for deletion. So I gave up on them.
Mapillary looks promising. If it were up to me they'd get a dedicated tag all for themselves:
But I also gave up on the voting process on the wiki. Even if a vote's result are positive, that doesn't mean or guarantee that that scheme will be rendered by the powers that be (yes, I'm talking about the 'new' public transport scheme).
So I'll probably simply start using that tag and be done with it.
This article is inspired by http://blog.openstreetmap.de/blog/2014/12/wochenaufgabe-kw-5152-oepnvfahrplanwechsel/ but adapted to how public transport is mapped in Belgium at the moment.
I also recorded an editing session in JOSM:
Apparently public transport companies do all the major changes to their time tables towards year's end. At least this seems the case for both Germany and Belgium. So we have some changes to process in Belgium as well.
In Germany they have weekly assignments. I guess that, over here, cleaning up the mapping of public transport, will become a task, that takes somewhat longer than a week to accomplish.
We also still have quite a large amount of lines that are mapped in the now deprecated way, using just one route in a futile attempt to describe all its variations. If all you wanted to do, is render on a map where the buses pass, this may be sufficient, but in case you want to describe actual itineraries, that is severely lacking. Those older routes take the longest to convert, but at least there is an approximate indication of the itinerary when they are present.
We have, however, many routes which are already on 'version 2'. The problem with those is that they are prone to change to the timetables/itineraries and they get broken by edits with inferior editors, which don't process relations properly.
This got me thinking about a way to:
keep them up-to-date in a practical way?
I've been working on scripts to automate the boring parts of this arduous task. The source code can be found here:
Incidentally those scripts also help when creating routes for bus and tram lines which aren't in OSM yet.
They depend heavily on the availability of PT data from De Lijn and TEC though. So their performance is optimal when such data is available, which isn't the case for the Brussels' operator MIVB/STIB, unfortunately. Those can be added in more traditional ways, but instead of starting from the stops to add an itinerary afterwards, it may make more sense to work the other way around.
On to the translation/adaptation of the German week assignment
Mapping public transport in OSM is a subject which is often poorly understood. The consequence is a multitude broken route relations, which don't get updated. For users of the data this is rather worthless. At the time of writing, it seems like 3, and possibly a few other, mapping schemes are in use (I found out recently that we deviate from what the wiki proscribes in Belgium as well, this article was started to describe at which points in detail).
Before starting to edit, some research might be needed. Does the route_master relation still describe an existing bus/tram line? Do the route relations still describe actual variations accurately?
Sometimes lines get new identifiers (line numbers). This occurred in Beringen recently:
I worked on updating those over the past week (Jan 2015). The changes happened in July 2014 though, I'm working on a way to detect such changes in a more timely way and to present to the community at large through a web interface.
To map public transport, you'll need an editor which can work correctly with relations, iD is not up to that task, as it's not possible to influence the order of the members with iD. And the order of relation members is crucially important in public transport route relations. (It is important in our cycle/walking node relations as well, if you want to do automatic validation on them, but that's another story).
JOSM is the only suitable editor to accomplish this task and not only because of the relation editor, but also because it's the only editor which supports the MapCSS to properly visualise the data and a scripting environment to use the scripts I created to help with the task.
New routes and all the ones we bring up-to-date, should be mapped according to the 'new' Scheme. For Belgium it's described here:
In the new scheme a separation is made between where the passengers wait and where the (front of the) bus/tram/train halts on the way. The latter is mapped as a node which is part of the way. Although all stops of De Lijn and TEC are now in OSM, these stop_positions were not always added. Please add them if you are already editing/splitting the way for other purposes.
public_transport=stop_position for bus stops add bus=yes for tram stops add tram=yes for train add train=yes
These nodes don't get extra information like name, ref, route_ref or zone. (at least in Belgium they don't)
When this serves as a terminal/initial stop for some of the served line variations, split the way at this point.
In case a platform is present, this can be entered as a way or an area.
To get them rendered add:
highway=platform for bus stops
railway=platform for tram stops
In case of a closed way for an area add
At the moment I haven't found a reason to use multipolygon relations for these.
In Belgium, these platforms don't get any extra tags, except for tactile_paving=yes/no if a way was used to map it and those foot massagers are present.
In case of an area was used for mapping the platform, it's probably better to add a highway=footway with tactile_paving=yes. The imagery of AGIV is good enough to determine where their extremities are. They look like white T's
To keep things simple and manageable all bus and tram stops in Belgium are mapped on nodes. I never considered moving the details like name, ref, route_ref and zone to platform ways, as that would result in them not being shown anymore by the MapCSS style I created for that purpose.
These nodes can designate the position of the pole, a corner on the shelter where the 'flag' is mounted, or if this is unknown, the position of the B of the word B U S, if visible on the aerial imagery.
In Belgium all bus and tram stops of De Lijn and TEC are now mapped, most of them by yours truly. (Click on the links if you want to download files converted to OSM format for verification). In case the position could not be determined from the aerial imagery these positions are approximate until somebody surveys and moves them.
TEC also provides shapefiles, which I converted to GPX. This is mostly interesting to know which streets the buses are likely to follow and to exclude the streets where they most certainly don't go.
In Brussels we can't seem to get permission to access to the data of MIVB/STIB, but the exact positions of the poles are in the dataset of UrbIS, which we are allowed to use. So we should be able to map the PT network in Brussels the (mostly) traditional way. UrbIS contains the tram rails as well. It's quite an undertaking to integrate them in OSM, but once they're in, it becomes trivial to add the tram lines. If you provide me with GPX files of your bus rides on lines in Brussels, I might even add/update them for you.
Some stops of De Lijn and TEC extend into the Brussels Region, The Netherlands, Germany, Luxembourg and France. All these were added to OSM as well. In fact, I did those first, to find out which was the best way to do so. At first I used dedicated nodes per operator, but that's not the proper way, after all (I was never entirely happy with doing it that way, but it had a few advantages as well in case some fields didn't happen to agree). Now each operator got their own 'namespace' and those nodes should all be merged by now.,
public_transport=platform for bus stops add bus=yes for tram stops add tram=yes for train add train=yes
For backward compatibility and to get them rendered:
add highway=bus_stop or railway=tram_stop
All bus/tram stop nodes have a unique ref to identify them. To make it possible to use a single node for multiple operators, these are mapped as:
ref:De_Lijn ref:TECB ref:TECC ref:TECH ref:TECN ref:TECL ref:TECX
Indeed, each entity of TEC assigned their own identifiers and for buses which wander into another provinces the stops have more than one.
For Veolia, Connexxion, MIVB/STIB, etc we can safely use:
But mostly we don't have identifiers for these.
Sometimes it's necessary to use separate namespaces for name as well:
When 2 entities of TEC don't happen to agree on the name to use, I just picked 1, mostly arbitrarily.
At some point we decided to include the name of the municipality as part of the name:
Making an exception for the larger cities like Antwerp, Brussels and Ghent. In retrospect I would prefer to start prepending Gent as well. For Charleroi and Liège, I simply included them as part of the name. For stops outside of Belgium this is not customary. For bilingual areas, I also dropped the village/city names, as they become rather long otherwise.
The same applies to route_ref. This tag includes all the lines which serve this bus stop.
For QC purposes one could also include not_served_by for those stops skipped by express buses, or when it's not possible to serve them as the bus makes a left turn across 2 lanes soon after where the halt is located.
It's possible to include
* shelter=yes/no * covered=yes/no * bench=yes/no * bin=yes/no
Or it's possible to map these as separate elements:
* amenity=shelter * shelter_type=public_transport * amenity=bench * amenity=waste_basket * building=roof
for bus stations you can add a node or an area tagged as * amenity=bus_station
All of the above can be collected in a stop_area relation. One stop_area relation for each highway=platform node. So in simple cases one for each side of the road.
All stop_area relations can be collected in stop_area_group relations. JOSM will complain about these. Let it. The validator may catch up some day, or not. They were in the initial 'new' PT scheme, and then they were dropped for some inexplicable reason.
Once the stops are mapped according to 'PTv2' - we can start adding route relations for all the variations. The good news is that in Belgium almost all stops have been added by now. The exception are those stops in Brussels which don't get served by De Lijn or TEC. Add OSM notes to the map with all their details and send me a link to the note for those, if you don't feel comfortable adding them directly.
In PTv2 there is one route relation per variant. So the simplest lines will have 2 variants, one for each direction (The exceptions confirming the rule are the Ringbus 600 and 601 in Leuven and some school buses like 586). The good news is that we can compile route relations for each of these variants automatically for lines run by De Lijn and TEC.
To keep the number of variants (and the work to keep them up-to-date) limited we only have a variant for the longest sequence of stops for telescopic routes. I believe it makes sense to save contributors' precious time and to limit the number of route relations, ways need to be members of. For rendering there is no difference (except that it means less processing) and for routing, it's relatively easy to cut out the ways sequence which is needed for a shorter sequence of stops. (I know it can be done, as I've scripted exactly that to assist contributors when creating new route relations)
Each route relation has all the stops at the end. These are the platform NODES mentioned higher up. These are the only nodes the conversion scripts know about, so these are the nodes which can be added automatically to the template routes it creates. Their order matters, of course. At some point I made the arbitrary decision to have the ways first, followed by the stops, as that's the way JOSM would sort them (if you were foolish enough to let it do that on all the members of the relation at once. JOSM can sort the ways fine, but it's smarter to give it a subset of just ways. It doesn't cope very well if ways are used more than once (loops, spoons)).
Apparently the wiki contradicts this and proscribes stops first, then ways. Ultimately I don't think it matters much, unless it would cause 'edit wars'. I prefer to have the ways first, as that is what contributors work on. The stops are added by a script, at least in our case.
If the bus uses a way more than once, it will be in the route more than once. The same goes for the stops, which get served more than once by the same variant. This is less common than ways being used more than once.
All variant routes belonging to the same line are collected in a master route relation.
Challenge: keep it all up-to-date
I will come up with a script which can make an overview of which routes are in need of attention. Hopefully I can get an account on a dev server to do so.
I found a nice little feature in JOSM: q makes rectangles with 90 degree angles. They look perfect while still in JOSM. Then it gets rendered and I end up with parallellograms. What's up with that? (and more importantly: what can I do to prevent it?)
I'll be mapping in and around Cusco for the next 5 weeks.
Just bought a new datalogger/GPS mouse. It's a nifty little thing which has 44 channels. It's very precise. I can use the IPAQ to connect to it over bluethooth, but it can also log on its own. 330000 points.
So from now on I'll have two independent gpx tracks to work with. If only I could find a way to set its clock. All the rest, I already achieved. BT access from the IPAQ and from the portable, translating the log output with GPSbabel and uploading it with josm.
Just completed the (probably nonsensical) job of entering the layout of our botanical garden with Potlatch.
Today I took care of the E40, E314 and the N25 in the neighbourhood of greater Leuven. I've been rectifying it with help of the Yahoo! imagery, adding an extra lane to the E40 going to Brussels, that is there for a few years already now.
Thanks to Potlatch and the courtesy of Yahoo! I've been able to do a lot of work. For entering the gpx's I use JOSM and I like it. When there is Yahoo! imagery I like to make a second pass with Potlatch to make it all fit.
The last few weeks I found a new way to map: by bus. The advantage is your hands are free and you're out of the cold and the rain. The disadvantage: often it goes too fast. Most of the street signs are too far away or in the wrong angle to be readable. Anyway, I'm exploring relations to put the bus routes on OSM as well.
Usually I take the bus till the end point and then I map a few streets there until a bus goes back. Hopefully I won't get stuck one day/night, when no buses happen to go back anymore...
Anyway, I'm glad I found this project. Now I only need to be careful not to waste too much time with it. It's pretty addictive.
I'm amusing myself a bit by tracing the river that flows through my home town. I just did a stretch of 20km from the nearest city upstream and now I'm getting ready to do the same 20km downstream, where it merges with another river.
Is it OK to do this by using the photographic material from Yahoo? I don't see anybody who is going to use a kayak to trace the flow of a river like this, risking an expensive GPS unit.
I've been editing a bit on the maps of my city. I find that there are some inaccuracies between the lines representing the streets and the Yahoo imagery. Am I supposed/allowed to fix this? As it is now, the streets (Tiensestraat/Blijde Inkomststraat) cross over the rooftops of the houses...