QGIS goodies

Just a short post in case you missed it.

Since some time QGIS is coorporating with spreadshirt.com, so we can open ‘virtual shops’ all over the world to sell QGIS t-shirst, caps and mugs.

So: check your size, and go via this page to the nearest QGIS-shop and make your friends jealous with our great QGIS shirts :-)

shop_tshirt

Oh, and the QGIS project receives a small percentage of this money to buy refreshments for during the hackfests…

Mozilla Stumbler layer: loading TMS and XYZ tilelayers in QGIS

Mozilla Location Service (MLS) layer

Personally I’m very interested in the Mozilla Location Service (MLS), I wrote an earlier article about it on my work (Zuidt.nl) blog.
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Key in this project is that both locations of wifi points and cell towers are crowdsourced and put in a open database, so everybody can use that data to determine his/her position on earth based on some info you get from your laptop or cell phone (without GPS).

This is only possible if as much people as possible start uploading this kind of locations, and as you can see on Mozilla’s overview map it is getting on steam now.

This map layer, showing all blue dot’s on places where locations have been recorded, is a ‘normal’ XYZ tile layer (epsg:3857) generated once a day by Mapbox if I’m correct. After reading Mishari Muqbil blogpost about how to add this ‘blue dot’ layer in OsmAnd android application, I was curious if I could also load this layer in QGIS.

After some searching I found the very nice ‘TileLayerPlugin’ from Minoru Akagi who also is the author of the beautifull Qgis2threejs plugin (have a look into it if you haven’t done so yet!).

So if you want to load xyz map tile layers, like OpenStreetMap, or this Mozilla Stumbler layer in QGIS, do the following:

– via the plugin manager, search for ’tilelayer’ and install the TileLayer Plugin.
– open it’s dialog (initially in the Web menu), and click the Settings button in it and point to some directory on your hard disk for the ‘External layer definition directory’
– in that directory, as you can read in the README at github, you have to put one .tsv file per xyz layer. Note that the values should REALLY be tab-separated, not space separted!
– for the MozStumbler file you need (one!) line like this (tab separated!):
MLSstumber MLSstumber https://d17pt8qph6ncyq.cloudfront.net/tiles/{z}/{x}/{y}.png 1 0 13 -180 -85.0 180.0 85.0
To find the exact cloudfront-url you need, have a look into this json file: in https://location.services.mozilla.com/map.json

As soon as you have those bits in place you can see the blue dots. have a look, the coverage of my hometown is growing:

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Arcgis rest service and other layers

But wait… isn’t that the Arcgis / arcgisonline World Topo Map I see there? Yes, it is, Adding one of these lines:
ArcgisWorldTopo esri http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer/tile/{z}/{y}/{x}.png 1 0 16 -180 -85.0 180.0 85.0
or
ArcgisWorldImagery esri http://server.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer/tile/{z}/{y}/{x}.png 1 0 16 -180 -85.0 180.0 85.0
makes it possible to see other arcgisonline mapserver rest tile services in QGIS.

In this way it is also possible to load OpenStreetmap Tiles in QGIS, save:
OpenStreetMap © OpenStreetMap contributors http://tile.openstreetmap.org/{z}/{x}/{y}.png 1 0 19
as osm.tsv and see OpenStreetmap in it’s full glory.

I’ve put some tsv files in this zip: http://qgis.nl/tilelayers.zip for you to try out.

Crowdsourced Street Level Photos

Another post of Mishari Muqbil made me aware of another crowd sourcing project: street level photo’s: http://www.mapillary.com/map

While still young, it’s a nice initiative to bring ‘power to the people’ instead of to the big companies :-)

QGIS 2.6.1 and QGIS 2.6 Documentation Released

QGIS 2.6.1

Just a short notice that the QGIS project (silently) released QGIS 2.6.1, a bug fix release for the latest stable version of QGIS 2.6 Brighton.

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Some notable fixes include:

– composer stuff which was not working ok
– not all attribute columns showing in attribute table
– metasearch (CSW plugin) was not working in 2.6 out of the box
– some possible crashes are fixed now

QGIS Documentation 2.6

Bigger news: The Documentation team has released the 2.6 Documentation!

You can find it at http://docs.qgis.org/2.6 or http://docs.qgis.org/latest.

The older (2.2) documentation has been updated to reflect the new 2.6 features. A new feature is that it now contains Help pages for all algorithms which can be used in Processing.

All new text is sent to Transifex. So most languages lost some percent on their ‘Total translated’ score, and can start working to regain their scores.

Thanks to all people who invested time into updating the Documentation and/or made the 2.6.1 release possible!

Using QGIS processing scripts

One of the area’s that QGIS is constantly improving is the ‘Processing framework’, Formerly known as the sextante framework and written in java, it is rewritten in Python by one of the original authors Victor Olaya and made part of QGIS since about QGIS 2.0.

I think it is VERY usefull and in use a lot already, but not so much people are writing about this. In this blogpost I use it as a tool to run some pyqgis code, but Processing is much much more! Read about it in docs and manuals.

Recently there were some questions in the mailing list, which I thought would be fun to solve with a Processing script (instead of writing some lines of code in the python console, or creating a plugin).

processingtoolbox

Continue reading Using QGIS processing scripts

A QGIS class room setup on Windows

Somebody in my neighbourhood is Windows Administrator on a ‘Middelbare School’ here in Haarlem, my hometown.

The school, het Mendelcollege, received a (Q)GIS intro by Margit Stapel of GisWijzer who is doing introductions for 10 – 14 year old childer with GIS. The school received this course from a GIS professional as part of the ‘national geo week‘.

qgismendel1

Continue reading A QGIS class room setup on Windows

Using MetaSearch plugin to search and load (meta)data from your National Georegister

We (mostly Tom Kralidis, Angelos Tzotsos with some additions by me) just released the MetaSearch Catalogue Client plugin for QGIS. The new plugin is an update of the CSWClient plugin from NextGIS. This new MetaSearch plugin makes searching metadata and using the services peanuts!

A Catalog Service for the Web (CSW), for example provided by the Dutch clearinghouse Nationaal Georegister, contains metadata about geographic data and services. The metadata not only provide descriptions, but can also contain hyperlinks to the services to directly view (e.g. WMS) or load (e.g. WFS and WCS) the geographic information.

Search and result based on several keywords in combination with a spatial constraint
Search and result based on several keywords in combination with a spatial constraint

Continue reading Using MetaSearch plugin to search and load (meta)data from your National Georegister

Temporary Fix for OpenLayers Plugin

Current development version of QGIS ( upcoming QVIS 2.0 ) has undergone a nessecary upgrade of the Python-Cpp glue (SIP) which temporarily broke almost all python plugins. Currently plugin devs are busy fixing their plugins to be usable on time for the real launch of QGIS 2.0.

One plugin notably missing plugin is the OpenLayers-plugin, which is very usefull to use Openstreetmap (or Google or Bing) as a quick reference underground in QGIS. In the mailinglist the OpenLayers-plugin made it clear that there was currently no time available to fix this in a way they want it to be fixed (that is in a way that the plugin keeps working in both 1.8 and 2.0) and that there will be time to work on it during the QGIS hackfest in Brighton in september.

The good news is that the code of the plugins is available on Github. Because it was just easier to fix it only for QGIS 2.0 I did a quick fix to be able to use the plugin on my own build of QGIS (users of QGIS 1.8 should use the official version). The fixes you can find in my Github repo.

This fixed plugins is available for download here, but note that you can only use it by downloading it and unpacking it in the right plugin directory. On Linux this is ~/.qgis2/python/plugins and on Windows somewhere near C:\Documents and Settings\you\.qgis2\python\plugins. Note also that this is a temporary hack and that in time there will be an offical ( better :-) ) fix from the original authors.

QGIS and WFS service caching

The dutch PDOK-services plugin is a simple plugin to load some national (PDOK) dataservices.

One of the available services is a Web Features Service (WFS), while a very handy service, calling the WFS service to load all roads in the Netherlands shows you the following result:

As you can see the blue bar are actually all the (road) features that you receive. This (rather) strange result is also what you get when you zoomed in to a much smaller area. One would expect that the features would be retrieved only within current Extent/BoundingBox, but QGIS show exact the same ‘bar’ of features.

But we/QGIS can make this work…

Continue reading QGIS and WFS service caching