Tag: gis

Last week I’ve been in Madeira at the hackfest, like all the past events this has been an amazing happening, for those of you who have never been there, a QGIS hackfest is typically an event where QGIS developers and other pasionate contributors like documentation writers, translators etc. gather together to discuss the future of their beloved QGIS software. QGIS hackfest are informal events where meetings are scheduled freely and any topic relevant to the project can be discussed. This time we have brought to the table some interesting topics like:

• the future of processing providers: should they be part of QGIS code or handled independently as plugins?
• the road forward to a better bug reporting system and CI platform: move to gitlab?
• the certification program for QGIS training courses: how (and how much) training companies should give back to the project?
• SWOT analysis of current QGIS project: very interesting discussion about the status of the project.
• QGIS Qt Quick modules for mobile QGIS app

Tehre were also some mentoring sessions where I presented:

• How to set up a development environment and make your first pull request
• How to write tests for QGIS (in both python and C++)

  At this link you can find all the video recordings of the sessions: https://github.com/qgis/QGIS/wiki/DeveloperMeetingMadeira2018   Here is a link to the Vagrant QGIS developer VM I’ve prepared for the session: https://github.com/elpaso/qgis-dev-vagrant/   I’ve got a good feedback from other devs about my sessions and I’m really happy that somebody found them useful, one of the main goals of a QGIS hackfest should really be to help other developers to ramp up quicly into the project. Other than that, I’ve also find the time to update to QGIS 3.0 some of my old plugins like GeoCoding and QuickWKT.   Thanks to Giovanni Manghi and to Madeira Government for the organizazion and thanks to all QGIS sponsors and donors!   About me: I started as a QGIS plugin author, continued as the developer of the plugin official repository at https://plugins.qgis.org and now I’m one of the top 5 QGIS core contributors. After almost 10 years that I’m in the QGIS project I’m now not only a proud member of the QGIS community but also an advocate for the open source GIS software movement.

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: https://www.qt.io/download-qt-for-application-development 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 https://github.com/qt/qtwebkit (you can just download the zip): Extract it somewhere and build it with

/opt/qt593/bin/qmake WebKit.pro
make -j9
sudo make install

  Same with QScintila2 from https://www.riverbankcomputing.com/software/qscintilla

/opt/qt593/bin/qmake qscintilla.pro
make -j9
sudo make install

  QWT is also needed and it can be downloaded from https://sourceforge.net/projects/qwt/files/qwt/6.1.3/ 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:

/opt/qt593/bin/qmake qwt.pro
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!  

Another great QGIS hackfest is gone, and it’s time for a quick report. The location was the Linux Hotel, one of the best places where open source developers could meet, friendly, geek-oriented and when the weather is good, like this time, villa Vogelsang is a wonderful place to have a beer in the garden while talking about software development or life in general. This is a short list of what kept me busy during the hackfest:

• fixed some bugs and feature requests on the official QGIS plugin repo that I’m maintaining since the very beginning
• make the QGIS official plugin repository website mobile-friendly
• QGIS Server Python Plugin API refactoring, I’ve completed the work on the new API, thanks to the ongoing server refactoring it’s now much cleaner than it was in the first version
• attribute table bugs: I started to address some nasty bugs in the attribute table, some of those were fixed during the week right after the hackfest
• unified add layer button, we had a productive meeting where we decided the path forward to implement this feature, thanks to Boundless that is funding the development, this feature is what’s I’m currently working on these days

Thanks to all QGIS donors and funders that made yet another great hackfest possible and in particular to Boundless Spatial Inc. for funding my personal expenses.