Tag: news

Oslandia is the main partner of OPENGIS.ch around QField. We are proud today to forward the announcement of the new QField release 3.4 “Ebo”.

Main highlights

A new geofencing framework has landed, enabling users to configure QField behaviors in relation to geofenced areas and user positioning. Geofenced areas are defined at the project-level and shaped by polygons from a chosen vector layer. The three available geofencing behaviours in this new release are:

• Alert user when inside an area polygon;
• Alert user when outside all defined area polygons and
• Inform the user when entering and leaving an area polygons.

In addition to being alerted or informed, users can also prevent digitizing of features when being alerted by the first or second behaviour. The configuration of this functionality is done in QGIS using QFieldSync.

Pro tip: geofencing settings are embedded within projects, which means it is easy to deploy these constraints to a team of field workers through QFieldCloud. Thanks Terrex Seismic for sponsoring this functionality.

QField now offers users access to a brand new processing toolbox containing over a dozen algorithms for manipulating digitized geometries directly in the field. As with many parts of QField, this feature relies on QGIS’ core library, namely its processing framework and the numerous, well-maintained algorithms it comes with.

The algorithms exposed in QField unlock many useful functionalities for refining geometries, including orthogonalization, smoothing, buffering, rotation, affine transformation, etc. As users configure algorithms’ parameters, a grey preview of the output will be visible as an overlay on top of the map canvas.

To reach the processing toolbox in QField, select one or more features by long-pressing on them in the features list, open the 3-dot menu and click on the process selected feature(s) action. Are you excited about this one? Send your thanks to the National Land Survey of Finland, who’s support made this a reality.

QField’s camera has gained support for customized ratio and resolution of photos, as well as the ability to stamp details – date and time as well as location details – onto captured photos. In fact, QField’s own camera has received so much attention in the last few releases that it was decided to make it the default one. On supported platforms, users can switch to their OS camera by disabling the native camera option found at the bottom of the QField settings’ general tab.

Wait, there’s more

There are plenty more improvements packed into this release from project variables editing using a revamped variables editor through to integration of QField documentation help in the search bar and the ability to search cloud project lists. Read the full 3.4 changelog to know more, and enjoy the release!

Contact us !

A question concerning QField ? Interested in QField deployment ? Do not hesitate to contact Oslandia to discuss your project !

Oslandia is the main partner of OPENGIS.ch around QField. We are proud today to forward the announcement of the new QField release 3.3 “Darién”. This release introduces a brand new plugin framework that empowers users to customize and add completely new functionalities to their favourite field application.

The plugin framework comes with other new features and improvements for this release, detailed below.

Main highlights

One of the biggest feature additions of this version is a brand new drawing tool that allows users to sketch out important details over captured photos or annotate drawing templates. This was a highly requested feature, which is brought to all supported platforms (Android, iOS, Windows, macOS, and, of course, Linux) with the financial support of the Swiss QGIS user group.

Also landing in this version is support for copying and pasting vector features into and from the clipboard. This comes in handy in multiple ways, from providing a quick and easy way to transfer attributes from one feature to another through matching field names to pasting the details of a captured feature in the field into a third-party messenger, word editing, or email application. Copying and pasting features can be done through the feature form’s menu as well as long pressed over the map canvas. Moreover, a new feature-to-feature attributes transfer shortcut has also been added to the feature form’s menu. Appreciation to Switzerland, Canton of Lucerne, Environment and Energy for providing the funds for this feature.

The feature form continues to gain more functionalities; in this version, the feature form’s value map editor widget has gained a new toggle button interface that can help fasten data entry. The interface replaces the traditional combo box with a series of toggle buttons, lowering the number of taps required to pick a value. The German Archaeological Institut – KulturGutRetter sponsored this feature.

Other improvements in the feature form include support for value relation item grouping and respect for the vector layer attributes’ « reuse last entered value » setting.

Finally, additional features include support for image decoration overlay, a new interface to hop through cameras (front, back, and external devices) for the ‘non-native’ camera, the possibility to disable the 3-finger map rotation gesture, and much more.

User experience improvements

Long-time users of QField will notice the new version restyling of the information panels such as GNSS positioning, navigation, elevation profile, and sensor data. The information is now presented as an overlay sitting on top of the map canvas, which increases the map canvas’ visibility while also achieving better focus and clarity on the provided details. With this new version, all details, including altitude and distance to destination, respect user-configured project distance unit type.

The dashboard’s legend has also received some attention. You can now toggle the visibility of any layer via a quick tap on a new eye icon sitting in the legend tree itself. Similarly, legend groups can be expanded and collapsed directly for the tree. This also permits you to show or hide layers while digitizing a feature, something which was not possible until now. The development of these improvements was supported by Gispo and sponsored by the National Land Survey of Finland.

Plugin framework

QField 3.3 introduces a brand new plugin framework using Qt’s powerful QML and JavaScript engine. With a few lines of code, plugins can be written to tweak QField’s behaviour and add new capabilities. Two types of plugins are possible: app-wide plugins as well as project-scoped plugins. To ensure maximum ease of deployment, plugin distribution has been made possible  through QFieldCloud! Amsa provided the financial contribution that brought this project to life.

Our partner OPENGIS.ch will soon offer a webinar to discover how QField plugins can help your field (and business) workflows by allowing you to be even more efficient in the field.

Users interested in authoring plugins or better understanding the framework, can already visit the dedicated documentation page and a sample plugin implementation sporting a weather forecast integration.

A question concerning QField ? Interested in QField deployment ? Do not hesitate to contact Oslandia to discuss your project !

Since 2018 and the arrival of Loïc Bartoletti, Oslandia has accelerated its focus on topography and topology within and around QGIS.

Two questions have driven this focus:

• How to draw directly in GIS by integrating drawing tools inspired by the CAD world into QGIS.
• How to integrate plugins for topographic calculations directly into QGIS.

To address this, Oslandia has worked on several fronts: training, developing open-source plugins, and improvements in QGIS.

1- Plugins

The following plugins were developed by Oslandia or partners, with contributions from Oslandia:

• landsurveycodesimport : https://gitlab.com/Oslandia/qgis/landsurveycodesimport
  A plugin for surveyors working with the point coding methodology in topography.
• QompliGIS : https://gitlab.com/Oslandia/qgis/qompligis
  A tool to ensure your dataset or plan complies with a specification.
• Total Open Station : https://github.com/totalopenstation
  An open-source project initiated by Italian and French archaeologists, it is a tool to convert various formats of survey field books.
• Topaze : https://gitlab.com/azimut-fr/qgis/topaze
  A topometric calculation tool developed with Jean-Marie Arsac (Azimut). It was a proof of concept that such calculations can be done within a GIS.

These plugins can be used at different stages of a project. They can be used all together or only those needed and integrated into workflows.

2- Improvements on QGIS

Oslandia also focuses on improving the core of QGIS. Last years, our teams have worked on:

— Integration of shape tools: circles, ellipses, rectangles, regular polygons, etc.
— Improvement of snapping tools.
— Enhancement of Z and M coordinate support.
— Improvement of topological tools (relationships between geometries).

Coming soon is the possibility to use geometry and topology validation and correction plugins directly in QGIS processing tools, developed by Jacky Volpès and Loïc Bartoletti.

3- Training

Oslandia is QUALIOPI certified and offers a training program around QGIS and QField:

• Drawing: Transition from CAD to GIS with QGIS: https://oslandia.com/formations/qgis3-dessiner-avec-qgis/
• Topography with QGIS (LSCI, Topaze, QompliGIS, Total Open Station)
• QField Training
• Deployment of QField Cloud

« In 2023, 89 people were trained by Oslandia, who recommend our training at 90.9%.»

4- And QField ?

Since our partnership with OPENGIS.ch, Oslandia offers QField Cloud server deployment services, training, and QField support.

5- Coming Soon!

Several technical posts are being prepared: how to open CAD files in a GIS? What are the differences between QField and LSCI? You will find them on our website in the coming weeks.

Additionally, we are preparing a white paper on the topic of migrating from CAD to QGIS, which we should release in September.

Stay tuned!

At OPENGIS.CH, we’ve been working lately on improving the DXF Export QGIS functionality for the upcoming release 3.38. In the meantime, we’ve also added nice UX enhancements for making it easier and much more powerful to use!

Let’s see a short review.

DXF Export app dialog and processing algorithm harmonized

You can use either the app dialog or the processing algorithm, both of them offer you equivalent functionality. They are now completely harmonized!

Export settings can now be exported to an XML file

You can now have multiple settings per project available in XML, making it possible to reuse them in your workflows or share them with colleagues.

All settings are now well remembered between dialog sessions

QGIS users told us there were some dialog options that were not remembered between QGIS sessions and had to be reconfigured each time. That’s no longer the case, making it easier to reuse previous choices.

“Output layer attribute” column is now always visible in the DXF Export layer tree

We’ve made sure that you won’t miss it anymore.

Possibility to export only the current map selection

Filter features to be exported via layer selection, and even combine this filter with the existing map extent one.

Empty layers are no longer exported to DXF

When applying spatial filters like feature selection and map extent, you might end up with empty layers to be exported. Well, those won’t be exported anymore, producing cleaner DXF output files for you.

Possibility to override the export name of individual layers

It’s often the case where your layer names are not clean and tidy to be displayed. From now on, you can easily specify how your output DXF layers should be named, without altering your original project layers.

We’ve also fixed some minor UX bugs and annoyances that were present when exporting layers to DXF format, so that we can enjoy using it. Happy DXF exporting!

We would like to thank the Swiss QGIS user group for giving us the possibility to improve the important DXF part of QGIS

QGIS-versioning is a QGIS and PostGIS plugin dedicated to data versioning and history management. It supports :

• Keeping full table history with all modifications
• Transparent access to current data
• Versioning tables with branches
• Work offline
• Work on a data subset
• Conflict management with a GUI

QGIS versioning conflict management

In a previous blog article we detailed how QGIS versioning can manage data history, branches, and work offline with PostGIS-stored data and QGIS. We recently added foreign key support to QGIS versioning so you can now historize any complex database schema.

This QGIS plugin is available in the official QGIS plugin repository, and you can fork it on GitHub too !

Foreign key support

TL;DR

When a user decides to historize its PostgreSQL database with QGIS-versioning, the plugin alters the existing database schema and adds new fields in order to track down the different versions of a single table row. Every access to these versioned tables are subsequently made through updatable views in order to automatically fill in the new versioning fields.

Up to now, it was not possible to deal with primary keys and foreign keys : the original tables had to be constraints-free.  This limitation has been lifted thanks to this contribution.

To make it simple, the solution is to remove all constraints from the original database and transform them into a set of SQL check triggers installed on the working copy databases (SQLite or PostgreSQL). As verifications are made on the client side, it’s impossible to propagate invalid modifications on your base server when you “commit” updates.

Behind the curtains

When you choose to historize an existing database, a few fields are added to the existing table. Among these fields, versioning_ididentifies  one specific version of a row. For one existing row, there are several versions of this row, each with a different versioning_id but with the same original primary key field. As a consequence, that field cannot satisfy the unique constraint, so it cannot be a key, therefore no foreign key neither.

We therefore have to drop the primary key and foreign key constraints when historizing the table. Before removing them, constraints definitions are stored in a dedicated table so that these constraints can be checked later.

When the user checks out a specific table on a specific branch, QGIS-versioning uses that constraint table to build constraint checking triggers in the working copy. The way constraints are built depends on the checkout type (you can checkout in a SQLite file, in the master PostgreSQL database or in another PostgreSQL database).

What do we check ?

That’s where the fun begins ! The first thing we have to check is key uniqueness or foreign key referencing an existing key on insert or update. Remember that there are no primary key and foreign key anymore, we dropped them when activating historization. We keep the term for better understanding.

You also have to deal with deleting or updating a referenced row and the different ways of propagating the modification : cascade, set default, set null, or simply failure, as explained in PostgreSQL Foreign keys documentation .

Nevermind all that, this problem has been solved for you and everything is done automatically in QGIS-versioning. Before you ask, yes foreign keys spanning on multiple fields are also supported.

What’s new in QGIS ?

You will get a new message you probably already know about, when you try to make an invalid modification committing your changes to the master database

Error when foreign key constraint is violated

Partial checkout

One existing Qgis-versioning feature is partial checkout. It allows a user to select a subset of data to checkout in its working copy. It avoids downloading gigabytes of data you do not care about. You can, for instance, checkout features within a given spatial extent.

So far, so good. But if you have only a part of your data, you cannot ensure that modifying a data field as primary key will keep uniqueness. In this particular case, QGIS-versioning will trigger errors on commit, pointing out the invalid rows you have to modify so the unique constraint remains valid.

Error when committing non unique key after a partial checkout

Tests

There is a lot to check when you intend to replace the existing constraint system with your own constraint system based on triggers. In order to ensure QGIS-Versioning stability and reliability, we put some special effort on building a test set that cover all use cases and possible exceptions.

What’s next

There is now no known limitations on using QGIS-versioning on any of your database. If you think about a missing feature or just want to know more about QGIS and QGIS-versioning, feel free to contact us at infos+data@oslandia.com. And please have a look at our support offering for QGIS.

Many thanks to eHealth Africa who helped us develop these new features. eHealth Africa is a non-governmental organization based in Nigeria. Their mission is to build stronger health systems through the design and implementation of data-driven solutions.

Last year we described a command line method that adds ESRI REST layers in QGIS. Well, a team at the Geometa Lab in the University of Applied Sciences Rapperswil (HSR) Switzerland, have released a plugin for QGIS that adds ESRI REST layers via a GUI (Github page). The plugin is experimental so you will need to tick the box “Show also experimental plugins” in the settings panel of the “Plugins – Manage and Install Plugins” dialogue in order to add the plugin to QGIS. The following URLs lists numerous REST layers in the plugin’s GUI:

http://services.arcgisonline.com/arcgis/rest/services

http://basemap.nationalmap.gov/arcgis/rest/services

http://services.nationalmap.gov/arcgis/rest/services

Reference:

REST API Connector Plug-in Wiki Page

Sea Surface Temperature data downloaded by Oceancolor Data Downloader.

The Oceancolor Data Downloader is a new plugin for QGIS from the Mapping and Geographic Information Centre of the British Antarctic Survey that downloads Oceancolor and Sea Surface Temperature data from NASA’s Oceancolor website. The plugin currently downloads three datasets:

• MODIS AQUA chlorophyll concentration
• SeaWiFS chlorophyll concentration
• MODIS AQUA night time Sea Surface Temperatures

The data accessed includes daily, 8 day, monthly and yearly composites, all of which can be saved to disk while downloading. Future plans for the plugin include additional access to other datasets such as ocean Net Primary Production, selection by bounding box, the ability to save in other formats, a progress bar etc.

I used the plugin to download global Sea Surface Temperatures for the 13th Jan 2015. I then used shapefiles from Natural Earth to create a simple basemap. I finally chose the IBCAO Polar Stereographic projection (EPSG: 3996) to create a map centred on the North Pole.

If you use the plugin to produce published research, please cite: