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3rd joint EARSeL LULC & NASA LCLUC Workshop

Following the success of the two previous EARSeL Special Interest Gr

The post 3rd joint EARSeL LULC & NASA LCLUC Workshop appeared first on GFOSS Blog | GRASS GIS Courses.

38th Annual EARSeL Symposium

Climate change, overpopulation, overexploitaion of natural resources

The post 38th Annual EARSeL Symposium appeared first on GFOSS Blog | GRASS GIS Courses.

Wind and Renewable Energy 2018

With the grand success of Wind & Renewable Energy 2016, Conferen

The post Wind and Renewable Energy 2018 appeared first on GFOSS Blog | GRASS GIS Courses.

Copernicus for Agriculture – Industry Workshop


The post Copernicus for Agriculture – Industry Workshop appeared first on GFOSS Blog | GRASS GIS Courses.

Climate Show 2018

The International Climate Show will be held at Palexpo, Geneva from

The post Climate Show 2018 appeared first on GFOSS Blog | GRASS GIS Courses.

8th European Algae Industry Summit

Following the success of its previous editions, ACI’s 8th European A

The post 8th European Algae Industry Summit appeared first on GFOSS Blog | GRASS GIS Courses.

European Geosciences Union General Assembly 2018

The EGU General Assembly 2018 will bring together geoscientists from

The post European Geosciences Union General Assembly 2018 appeared first on GFOSS Blog | GRASS GIS Courses.

QGIS 3 compiling on Windows

As the Oslandia team work exclusively on GNU/Linux, the exercise of compiling QGIS 3 on Windows 8 is not an everyday’s task :). So we decided to share our experience, we bet that will help some of you.


The first step is to download Cygwin and to install it in the directory C:\cygwin (instead of the default C:\cygwin64). During the installation, select the lynx package:


Once installed, you have to click on the Cygwin64 Terminal icon newly created on your desktop:

Then, we’re able to install dependencies and download some other installers:

$ cd /cygdrive/c/Users/henri/Downloads
$ lynx -source > apt-cyg
$ install apt-cyg /bin
$ apt-cyg install wget git flex bison
$ wget
$ chmod u+x vs_community_ENU.exe
$ wget
$ wget
$ chmod u+x osgeo4w-setup-x86_64.exe


The next step is to install CMake. To do that, double clic on the file cmake-3.7.2-win64-x64.msi previously downloaded with wget. You should choose the next options during the installation:


Visual Studio

Then, we have to install Visual Studio and C++ tools. Double click on the vs_community_ENU.exe file and select the Custom installation. On the next page, you have to select Visual C++ chekbox:




In order to compile QGIS, some dependencies provided by the OSGeo4W installer are required. Double click on osgeo4w-setup-x86_64.exe and select the Advanced Install mode. Then, select the next packages:

  •  expat
  • fcgi
  • gdal
  • grass
  • gsl-devel
  • iconv
  • libzip-devel
  • libspatialindex-devel
  • pyqt5
  • python3-devel
  • python3-qscintilla
  • python3-nose2
  • python3-future
  • python3-pyyaml
  • python3-mock
  • python3-six
  • qca-qt5-devel
  • qca-qt5-libs
  • qscintilla-qt5
  • qt5-devel
  • qt5-libs-debug
  • qtwebkit-qt5-devel
  • qtwebkit-qt5-libs-debug
  • qwt-devel-qt5
  • sip-qt5
  • spatialite
  • oci
  • qtkeychain


To start this last step, we have to create a file C:\OSGeo4W\OSGeo4W-dev.bat containing something like:

@echo off 
call "%OSGEO4W_ROOT%\bin\o4w_env.bat" 
call "%OSGEO4W_ROOT%\bin\qt5_env.bat" 
call "%OSGEO4W_ROOT%\bin\py3_env.bat" 
set VS140COMNTOOLS=%PROGRAMFILES(x86)%\Microsoft Visual Studio 14.0\Common7\Tools\ 
call "%PROGRAMFILES(x86)%\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" amd64 
set INCLUDE=%INCLUDE%;%PROGRAMFILES(x86)%\Microsoft SDKs\Windows\v7.1A\include 
set LIB=%LIB%;%PROGRAMFILES(x86)%\Microsoft SDKs\Windows\v7.1A\lib 
path %PATH%;%PROGRAMFILES%\CMake\bin;c:\cygwin\bin 
@set GRASS_PREFIX="%OSGEO4W_ROOT%\apps\grass\grass-7.2.1 
@set LIB=%LIB%;%OSGEO4W_ROOT%\lib;%OSGEO4W_ROOT%\lib 


According to your environment, some variables should probably be adapted. Then in the Cygwin terminal:

$ cd C:\
$ git clone git://
$ ./OSGeo4W-dev.bat
> cd QGIS/ms-windows/osgeo4w

In this directory, you have to edit the file package-nightly.cmd to replace:

cmake -G Ninja ^


cmake -G "Visual Studio 14 2015 Win64" ^

Moreover, we had to update the environment variable SETUAPI_LIBRARY according to the current position of the Windows Kits file SetupAPI.Lib:

set SETUPAPI_LIBRARY=C:\Program Files (x86)\Windows Kits\8.1\Lib\winv6.3\um\x64\SetupAPI.Lib

And finally, we just have to compile with the next command:

> package-nightly.cmd 2.99.0 1 qgis-dev x86_64


And see you soon for the generation of OSGEO4W packages 😉




PostgreSQL backend sollution for quality assurance and data archiving

Did you know that the possibilities to make a full QGIS backend solution for quality assurance and archiving in PostgreSQL are immense? SQL has it’s well known limitations, but with enough creativity you could create quite nice solutions just using

Data exploration with Data Plotly for QGIS3

Data Plotly is a new plugin by Matteo Ghetta for QGIS3 which makes it possible to draw D3 graphs of vector layer attribute values. This is a huge step towards making QGIS a one stop shop for data exploration!

Data Plotly adds a new panel where graphs can be configured and viewed. Currently, there are nine different plot types:

The following examples use tree cadastre data from the city of Linz, Austria.

Scatter plots with both two and three variables are supported. After picking the attributes you want to visualize, press “Create plot”.

If you change some settings and press “Create plot” again, by default, the new graph will be plotted on top of the old one. If you don’t want that to happen, press “Clean plot canvas” before creating a new plot.

The plots are interactive and display more information on mouse over, for example, the values of a box plot:

Even aggregate expressions are supported! Here’s the mean height of trees by type (deciduous L or coniferous N):

For more examples, I strongly recommend to have a look at the plugin home page.


W repozytorium Politechniki Krakowskiej zostało udostępnione elektroniczne wydanie podręcznika „Systemy informacji przestrzennej z QGIS, część I i II”, który ukazał się w roku 2017. W tym wydaniu dodano tematy związane z przetwarzaniem zdjęć satelitarnych oraz pracę z bazami danych przestrzennych.


W repozytorium Politechniki Krakowskiej zostało udostępnione elektroniczne wydanie podręcznika „Systemy informacji przestrzennej z QGIS, część I i II”, który ukazał się w roku 2017. W tym wydaniu dodano tematy związane z przetwarzaniem zdjęć satelitarnych oraz pracę z bazami danych przestrzennych.


W repozytorium Politechniki Krakowskiej zostało udostępnione elektroniczne wydanie podręcznika „Systemy informacji przestrzennej z QGIS, część I i II”, który ukazał się w roku 2017. W tym wydaniu dodano tematy związane z przetwarzaniem zdjęć satelitarnych oraz pracę z bazami danych przestrzennych.

Documentation for QGIS 3.0 – call for contributions!

Dear QGIS users, enthusiasts and fine people out there. QGIS 3.0 is coming very soon….we are in a ‘soft freeze’ state at the moment while we wait for some critical last pieces of code to get finalised. Then we go into hard freeze and prepare to roll out our next major release. Those of you that have been playing with the ‘2.99’ builds will surely have noticed that QGIS 3.0 is going to feature a huge number of improvements and new features – both in the user interface and in the API and code internals.

Screen Shot 2017-12-03 at 23.05.34

But we have a BIG problem:
we need your help to document and describe all those fine new features!

Yes fine reader now is the time to break out of the ‘passive user of QGIS’ mould you might find yourself in and lend a hand. We have an issue tracker with an issue for each of the new features that has landed in QGIS 3.0. Even if you do not know how to use our Sphinx based documentation system, you can help tremendously by preparing the prose that should be used to describe new features and attaching it to the issue list linked to above. If you do that, the documentation team can do more editorial work and less  ‘writing from scratch’ work.

Writing documentation is a brilliant way to enhance your own knowledge of QGIS and learn the new features that are coming in the next release. For those starting out with documentation there are issue reports that are tagged “easy” to lower the barrier for beginners. If you are an existing documentation team member it would be great if you could review the list and check whether there are more issues that can be tagged as “easy”.

The issue list is automatically created whenever a developer commits a change to QGIS with the word ‘FEATURE’ in their change notes. In some cases the change may not be something that an end user will be able to see – so it will be great for volunteers to also review the automatically added issues and close off any that are not relevant for documentation.

Other features are quite complex and in some cases could benefit from interaction with the original developer to make sure that the nuances of the new features are properly described. We need documentation writers to follow these thread and present the new functionality in a clear and concise way.

There are some very helpful resources for people just getting started with QGIS documentation. You can read the documentation for contributors. You can also contact the team via the community mailing list for specific help if the contributor docs don’t provide the information you need.

If you want to see the QGIS Documentation up-to-date for the version 3.0 release, please do get involved and help Yves Jacolin and the documentation team!

Lastly if you are not able to directly contribute to the documentation, consider funding QGIS – we have a budget for documentation improvements.

We look forward to your support and contributions!


Tim Sutton (QGIS Project Chairman)





Building QGIS master with Qt 5.9.3 debug build

Building QGIS from sources is not hard at all on a recent linux box, but what about if you wanted to be able to step-debug into Qt core or if you wanted to build QGIS agains the latest Qt release? Here things become tricky. This short post is about my experiments to build Qt and and other Qt-based dependencies for QGIS in order to get a complete debugger-friendly build of QGIS.   Start with downloading the latest Qt installer from Qt official website: choose the Open Source version.   Now install the Qt version you want to build, make sure you check the Sources and the components you might need. Whe you are done with that, you’ll have your sources in a location like /home/user/Qt/5.9.3/Src/ To build the sources, you can change into that directory and issue the following command – I assume that you have already installed all the dependencies normally needed to build C++ Qt programs – I’m using clang here but feel free to choose gcc, we are going to install the new Qt build into /opt/qt593.

./configure -prefix /opt/qt593 -debug -opensource -confirm-license -ccache -platform linux-clang
When done, you can build it with
make -j9
sudo make install
  To build QGIS you also need three additional Qt packages   QtWebKit from (you can just download the zip): Extract it somewhere and build it with
make -j9
sudo make install
  Same with QScintila2 from
make -j9
sudo make install
  QWT is also needed and it can be downloaded from but it requires a small edit in qwtconfig.pri before you can build it: set QWT_INSTALL_PREFIX = /opt/qt593_libs/qwt-6.1.3 to install it in a different folder than the default one (that would possibly overwrite a system install of QWT). The build it with:
make -j9
sudo make install
  If everything went fine, you can now configure Qt Creator to use this new debug build of Qt: start with creating a new kit (you can probably clone a working Qt5 kit if you have one). What you need to change is the Qt version (the path to cmake) to point to your brand new Qt build,: Pick up a name and choose the Qt version, but before doing that you need to click on Manage… to create a new one: Now you should be able to build QGIS using your new Qt build, just make sure you disable the bindings in the CMake configuration: unfortunately you’d also need to build PyQt in order to create the bindings.   Whe QGIS is built using this debug-enabled Qt, you will be able to step-debug into Qt core libraries! Happy debugging!  

Interlis translation

Lately, I have been confronted with the need of translating Interlis files (from French to German) to use queries originally developed for German data. I decided to create an automated convertor for Interlis (version 1) Transfer Format files (.ITF) based

Intro to QGIS3 3D view with Viennese building data

In this post, I want to show how to visualize building block data published by the city of Vienna in 3D using QGIS. This data is interesting due to its level of detail. For example, here you can see the Albertina landmark in the center of Vienna:

an this is the corresponding 3D visualization, including flying roof:

To enable 3D view in QGIS 2.99 (soon to be released as QGIS 3), go to View | New 3D Map View.

Viennese building data ( is provided as Shapefiles. (Saber Razmjooei recently published a similar post using data from New York City in ESRI Multipatch format.) You can download a copy of the Shapefile and a DEM for the same area from my dropbox.  The Shapefile contains the following relevant attributes for 3D visualization

  • O_KOTE: absolute building height measured to the roof gutter(?) (“absolute Gebäudehöhe der Dachtraufe”)
  • U_KOTE: absolute height of the lower edge of the building block if floating above ground (“absolute Überbauungshöhe unten”)
  • HOEHE_DGM: absolute height of the terrain (“absolute Geländehöhe”)
  • T_KOTE: lowest point of the terrain for the given building block (“tiefster Punkt des Geländes auf den Kanten der Gebäudeteilfläche”)

To style the 3D view in QGIS 3, I set height to “U_KOTE” and extrusion to


both with a default value of 0 which is used if the field or expression is NULL:

The altitude clamping setting defines how height values are interpreted. Absolute clamping is perfect for the Viennese data since all height values are provided as absolute measures from 0. Other options are “relative” and “terrain” which add given elevation values to the underlying terrain elevation. According to the source of qgs3dutils:

  AltClampAbsolute,   //!< Z_final = z_geometry
  AltClampRelative,   //!< Z_final = z_terrain + z_geometry
  AltClampTerrain,    //!< Z_final = z_terrain

The gray colored polygon style shown in the map view on the top creates the illusion of shadows in the 3D view:


Beyond that, this example also features elevation model data which can be configured in the 3D View panel. I found it helpful to increase the terrain tile resolution (for example to 256 px) in order to get more detailed terrain renderings:

Overall, the results look pretty good. There are just a few small glitches in the rendering, as well as in the data. For example, the kiosik in front of Albertina which you can also see in the StreetView image, is lacking height information and therefore we can only see it’s “shadow” in the 3D rendering.

So far, I found 3D rendering performance very good. It works great on my PC with Nvidia graphics card. On my notebook with Intel Iris graphics, I’m unfortunately still experiencing crashes which I hope will be resolved in the future.

New version of dutch PDOK services plugin

A short post in Dutch, to let us dutchies know of a new version of the ‘PDOK services plugin’ which eases the use of our national OWS services. If you want you can install it, and for example view the different soli types of The Netherlands: Another nice service is the 25cm Aerial Map of … Continue reading New version of dutch PDOK services plugin

Movement data in GIS #11: FOSS4G2017 talk recordings

Many of the topics I’ve covered in recent “Movement data in GIS” posts, have also been discussed at this year’s FOSS4G. Here’s a list of videos for you to learn more about the OGC Moving Features standard, modelling AIS data with FOSS, and more:

1. Introduction to the OGC Moving Features standard presented by Kyoung-Sook Kim from the Artificial Intelligence Research Center, Japan:

Another Perspective View of Cesium for OGC Moving Features from FOSS4G Boston 2017 on Vimeo.

2. Modeling AIS data using GDAL & PostGIS presented by Morten Aronsen from the Norwegian Defence Research Establishment:

Density mapping of ship traffic using FOSS4G in C# .NET from FOSS4G Boston 2017 on Vimeo.

3. 3D visualization of movement data from videos presented by Anna Petrasova from the Center for Geospatial Analysis, North Carolina State University:

Visualization and analysis of active transportation patterns derived from public webcams from FOSS4G Boston 2017 on Vimeo.

There are also a ton of Docker presentations on the FOSS4G2017 Vimeo channel, if you liked “Docker basics with Geodocker GeoServer”.

Read more:

Live stream link

Here is the link to the live stream of the QGIS UK user group meeting in Edinburgh on Thursday.

Videos of the individual talks will be available after the event.

Supported and sponsored by thinkWhere, Ordnance Survey, Cawdor Forestry, EDINA (venue), WRLD3D, Angus Council, Registers of Scotland, Product Forge (streaming), OSGeo:UK (finance)

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