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Extracting POIs from OpenStreetMap is reasonably simple using Overpass API. A very convenient way to construct the query is to use a query builder which allows you to select the area of interest and builds queries for different servers.

xapi_query_builder

Of course you can fine-tune the query further. For example, you can add multiple key-value pairs to the query. I used the following query to select all Billa supermarkets:

http://www.overpass-api.de/api/xapi?*[shop=supermarket][name=Billa][bbox=15.96725,48.0432,16.79947,48.40915]

Note to * in the query? It means that I’m querying all kinds of features: nodes, ways, and relations.

Save the server response to a .osm file. This file can be loaded into QGIS using simple drag-and-drop or Add Vector Layer. A dialog will open where you can select the type of features you want to load from the file. You can simply use Select All and OK to load everything.

add_osm_file

My supermarket POIs came in two types: points and multipolygons. To style them both with nice supermarket SVG icons, I decided to use a Centroid fill with the SVG marker for the polygon layer:

osm_pois_billa

Open data and open source GIS … nice :-)

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Today was the last day of the Vienna code sprint which brought together OSGeo developers from many projects. It’s been a great week thanks to organizers and sponsors!

The QGIS team was extremely busy working on the project’s web infrastructure (e.g. new plugins.qgis.org website) as well as hunting down and fixing bugs.

Check out some impressions on twitter.

qgis23_vienna

More pictures on the official blog: vienna2014.sprint.osgeo.org

If you are looking for a tool to easily create 3D visualizations of your geodata, look no further! Qgis2threejs is a plugin by Minoru Akagi which exports terrain data combined with the map canvas image and optional vector data to an html file which can be viewed in 3D in any web browser which supports WebGL. To do that, this plugin uses the Three.js library.

This is the result of my first experiments with Qgis2threejs. In the following sections, I will show the steps to reproduce it.

Türkenschanzpark, Vienna

click for the interactive version (requires WebGL-capable browser)

1. The data

The building blocks of this visualization are:

  • elevation data and the hillshade derived from this data
  • a base map (WMTS from basemap.at in my case)
  • OSM building data provided by Geofabrik and
  • tree data from the city of Vienna

Load all datasets into QGIS.

2. Preparing the map

Qgis2threejs will overlay the map (as rendered in the QGIS map area) on top of the elevation model. You can combine any number of layers to create your map. I just loaded a basemap.at WMTS and a hillshade layer. To add a nice tree shadow effect, I also added the tree layer (dark grey, 50% transparency, multiply blending).

tuerkenschanzpark_map

3. Preparing the vector features

The vector features in the visualization are buildings and trees. The buildings are based on an OSM building layer. The trees are create from two point layers: one point layer to create the tree trunks (cylinder shape) and a duplicate of this point layer to create the tree crowns (sphere shape).

Load the data and choose the desired fill colors.

4. Using Qgis2threejs

Now we can start Qgis2threejs. The first tab is used to configure the terrain. Just pick the correct elevation data layer. I didn’t modify any of the other default settings.

qgis2threejs_dem

The second tab provides the settings for the vector data. As mentioned in the previous section, the trees are created from two point layers and the buildings are based on a polygon layer. The tree crowns are spheres with a radius size 3 and a z value of 5 above the surface. The tree trunks are cylinders. Finally, the buildings have a height of 10.

qgis2threejs_vector

That’s it! Just press “run” and wait. When the export is finished, your default browser (or a different one, if you specify another one in the plugin settings) will open automatically and display the results.
The visualization is interactive. You can tilt the visualization using the left mouse button, pan using the right mouse button, and zoom using the mouse wheel. I found that Firefox used around 1.6 GB of RAM to render this example.

5. Share your visualization

In the browser window, you will see where Qgis2threejs stored the html and associated Javascript files. To share your visualization, you just need to copy these files onto a webserver.

I would love to see what you come up with. Please share a link in the comments.

QGIS 2.2 is now available for Windows through OSGeo4W installer. Packages for other systems are being prepared by the package maintainers.

The Windows packages are currently marked experimental, so you have to use the advanced install in OSGeo4W and check the ‘Exp’ radio button on the top to install them.

osgeo4w_qgis22

As release manager Jürgen Fischer announced:

Please test and report problems, so that I can soon promote them to ‘curr’ent.
Once that has happend, I’ll proceed with turning them into standalone
installers.

QGIS 2.2 will be released tomorrow, February 21st. Following the release of 2.0, the QGIS project decided to move to a time-based release plan with releases every four months. This provides a clear framework for developers, translators and documenters which makes it possible to plan ahead and know when tasks have to be finished to be included in a release version.

Similar to the 2.0 release, the project has invested considerable resources to make 2.2 “Valmiera” a successful release. I have already blogged about some of the great new features. Thanks to the project donors and sponsors it was also possible to fund developer time for many important bug fixes.

One of the greatest resources of the QGIS project are its users. One group that deserves our special thanks is the Swiss QGIS User Group. They collect a modest annual membership fee which provides a steady and growing crowd-funding that can be used to positively influence the QGIS project. For example, they invested in bug fixing for 2.0 and they are co-funding work on multi-threaded rendering for QGIS 2.4.

With the rise of new QGIS user groups “QUGs” all around the world, e.g. in Australia, the UK, and the US, I hope these groups will find ways to bring users together and to positively influence the development of QGIS towards the next releases.

This weekend, I had the pleasure to join Tim Sutton for the second edition of the QGIS Podcast. Every episode, the podcast aims to summarize the latest mailing list discussions and greatest new features.
This episode’s topics include: new CAD tools, usability and the new UX mailing list, new QGIS user groups (QUGs), point cloud support plans, and QGIS design.

If you would like to ask a question or suggest a topic, you can write to podcast@qgis.org.

If you want to become an active part of this year’s FOSS4G, it’s now time to start thinking about your contributions!

FOSS4G 2014 will be taking place in Portland, Oregon, USA from Sept 8th-12th. Like last year in Nottingham, there will be a regular track for presentations as well as an academic track and a series of workshops.

logo_horiz_500x231

If you are looking for inspiration, you might want the check out last year’s programme or read about the interesting story behind this years conference logo.

With the major release of version 2.0, QGIS is once more returning to a fast release cycle. You can find the project road map on qgis.org. The QGIS 2.2 release is scheduled for Feb, 21st and we are already in feature freeze. This means that now is the time to get the nightly version, do some testing and report possible bugs before the new version is being shipped.

Like for version 2.0, the QGIS team has prepared a great visual change log listing many new features. For me, one of the feature highlights is the possibility to export maps with world files from Print Composer because it means that we can finally create high-resolution, georeferenced images comfortably from within the application.

Another feature which will help save a lot of time is the ability to invert color ramps. So far, we had to recreate the color ramp or use work-arounds involving expression-based color settings to achieve the same effect.

invertcolorramp

These are just my personal favorites. If you haven’t checked out the change log yet, I certainly encourage you to have a look and decide for yourself. Also, if you find the time, please help by testing and reporting any issues you encounter. This way, we can all help to make 2.2 another successful release.

and thank you for a great 2013!

It has been a very busy year between writing my first book, going to FOSS4G, writing my first journal article and continuing to write this blog. The blog view counter shows a staggering 310,000 views for 2013.

The most popular posts of 2013 were:

  1. pgRouting 2.0 for Windows quick guide
  2. Vintage map design using QGIS
  3. Group Stats tutorial
  4. the Print Composer 2.0 series
  5. and Public transport isochrones with pgRouting

All the best for 2014!

OSM place search and osmSearch are two plugins for QGIS which use the Nominatim service to find addresses and places. They are both still marked as “experimental” plugins, so users are expected to expect the unexpected.

Once installed, both plugins look very similar: There is an input text field and a results list.

osmsearch_giefinggasse

A simple search with street name and house number returns the expected results. Interacting with the result shows some differences:

  • OSM place search will highlight the location when you mouse-over the result in the list. On double-click, it will zoom to the result.
  • osmSearch will highlight the result and move the map center to the result if you double-click but won’t zoom.

Both plugins can deal with umlauts (ä,ö,ü) but only osmSearch works with háčeks.

osmsearch_hacek

A nice feature of osmSearch is that it remembers your previous searches and offers an auto-complete function.

OSM place search on the other hand offers a reverse “Where am I” function (the arrow pointing to the left” which tries to find a name for the current map center location. Additionally, there are functions to add the current object as a new layer or mask layer.

Both plugins have strong and weak points. Combined, they would make a really strong tool but then nothing prevents us from having them both and choosing the best one for the task at hand.

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