Array nel field calc

Introduzione

Il gruppo Array è stato introdotto in QGIS nella prima versione di QGIS 3.0 Girona nel lontano 2018, nella descrizione leggiamo:

!!! Abstract "GRUPPO ARRAY" Nuovo gruppo che contiene funzioni di espressione per la creazione e la manipolazione di array (noti anche come strutture di dati di elenco). L'ordine dei valori all'interno dell'array è importante, contrariamente alla struttura dei dati "mappa", dove l'ordine delle coppie chiave-valore è irrilevante e i valori sono identificati dalle rispettive chiavi.

Impostazioni di progetto influenzano alcune funzioni

Introduzione

Alcune funzioni di QGIS dipendono dalle impostazioni di progetto, questo significa che le stesse funzioni in progetti diversi possono restituire valori diversi. In questo post vedremo le principali funzioni di QGIS da attenzionare.

!!! Abstract "esempio" $area <> area(@geometry)

Come cercare un valore in funzione di un altro

Introduzione

Alcune volte nasce l'esigenza di cercare un valore in una tabella in funzione di un altro valore presente nella stessa tabella, un po' come fa la funzione cerca verticale di Excel, e utilizzarlo in un altro layer.

!!! Abstract "Funzione" La funzione che permette di fare questa magia è la funzione get_feature

HfcQGIS e la sezione Blog

Introduzione

Benvenuti nel nuovo blog di HfcQGIS!

HfcQGIS è la guida al calcolatore di campi di QGIS per la condivisione di conoscenze ed ora ha il suo Blog!!!.

HfcQGIS è un sito web nato nel 2018 da un'idea di Totò Fiandaca e realizzato con la comunità OpenDataSicilia, un particolare grazie va a Giovan Battista Vitrano che mantiene sempre aggiornato il tema del sito alle ultime novità. L'obiettivo iniziale del sito era quello di fornire una guida completa al calcolatore di campi, un potente strumento che consente di eseguire calcoli sui dati geografici.

Negli anni, HfcQGIS si è evoluto in una piattaforma di condivisione di contenuti per la comunità QGIS. Il sito offre ora una serie di risorse, tra cui:

Growing up, I would spend hours lost in National Geographic maps. The feeling of discovering new regions and new ways to view the world was addictive! It’s this same feeling of discovery and exploration which has made me super excited about Soar’s Digital Atlas. Soar is the brainchild of Australian, Amir Farhand, and is fuelled by the talents of staff located across the globe to build a comprehensive digital atlas of the world’s maps and images. Soar has been designed to be an easy to use, expansive collection of diverse maps from all over the Earth. A great aspect of Soar is that it has implemented Strong Community Guidelines and moderation to ensure the maps are fit for purpose.

Recently, North Road collaborated with Soar to help facilitate their digital atlas goals by creating a QGIS plugin for Soar. The Soar plugin allows QGIS users to directly:

• Export their QGIS maps and images straight to Soar
• Browse and load maps from the entire Soar public catalogue into their QGIS projects

There’s lots of extra tweaks we’ve added to help make the plugin user friendly, whilst offering tons of functionality that power users want. For instance, users can:

• Filter Soar maps by their current project extent and/or by category
• Export raw or rendered raster data directly to Soar via a Processing tool
• Batch upload multiple maps to Soar
• Incorporate Soar map publishing into a Processing model or Python based workflow

Soar will be presenting their new plugin at the QGIS Open Day in August so check out the details here and tune in at 2300 AEST or 1300 HR UTC. You can follow along via either YouTube or Jitsi.

Browsing Soar maps from QGIS

One of the main goals of the Soar QGIS plugin was to make it very easy to find new datasets and add them to your QGIS projects. There’s two ways users can explore the Soar catalog from QGIS:

You can open the Soar Browser Panel via the Soar toolbar button  . This opens a floating catalog browser panel which allows you to interactively search Soar’s content while working on your map.

Alternatively, you can also access the Soar catalog and maps from the standard QGIS Data Source Manager dialog. Just open the “Soar” tab and search away!

When you’ve found an interesting map, hit the “Add to Map” button and the map will be added as a new layer into your current project. After the layer is loaded you can freely modify the layer’s style (such as the opacity, colorization, contrast etc) just like any other raster dataset using the standard QGIS Layer Style controls.

Sharing your maps

Before you can share your maps on Soar, you’ll need to first sign up for a free Soar account.

We’ve designed the Soar plugin with two specific use cases in mind for sharing maps. The first use case is when you want to share an entire map (i.e. QGIS project) to Soar. This will publish all the visible content from your map onto Soar, including all the custom styling, labeling, decorations and other content you’ve carefully designed. To do this, just select the Project menu, Import/Export -> Export map to Soar option.

You’ll have a chance to enter all the metadata and descriptive text explaining your map, and then the map will be rendered and uploaded directly to Soar.

All content on the Soar atlas is moderated, so your shared maps get added to the moderation queue ready for review by the Soar team. (You’ll be notified as soon as the review is complete and your map is publicly available).

Alternatively, you might have a specific raster layer which you want to publish on Soar. For instance, you’ve completed some flood modelling or vegetation analysis and want to share the outcome widely. To do this, you can use the “Publish dataset to Soar” tool available from the QGIS Processing toolbox:

Just pick the raster layer you want to upload, enter the metadata information, and let the plugin do the rest! Since this tool is made available through QGIS’ Processing framework, it also allows you to run it as a batch process (eg uploading a whole folder of raster data to Soar), or as a step in your QGIS Graphical Models!

Some helpful hints

All maps uploaded to Soar require the following information:

• Map Title
• Description
• Tags
• Categories
• Permission to publish

This helps other users to find your maps with ease, and also gives the Soar moderation team the information required for their review process.

We’ve a few other tips to keep in mind to successfully share your maps on Soar:

• The Soar catalog currently works with raster image formats including GeoTIFF / ECW / JP2 / JPEG / PNG
• All data uploaded to Soar must be in the WGS84 Pseudo-Mercator (EPSG: 3857) projection
• Check the size of your data before sharing it, as a large size dataset may take a long time to upload

So there you have it! So simple to start building up your contribution to Soar’s Digital Atlas. Those who might find this useful to upload maps include:

• Community groups
• Hobbyists
• Building a cartographic/geospatial portfolio
• Education/research
• Contributing to world events (some of the biggest news agencies already use this service i.e. BBC)

You can find out more about the QGIS Soar plugin at the QGIS Open Day on August 23rd, 2023 at 2300 HR AEST or 1300 HR UTC. Check here for more information or to watch back after.

If you’re interested in exploring how a QGIS plugin can make your service easily accessible to the millions of daily QGIS users, contact us to discuss how we can help!

Years ago, the QField community and its users showed their love for their favourite field app by supporting a successful crowdfunding to improve camera handling.

Since then, OPENGIS.ch has continued to lead the development of QField with the regular support of sponsors. We couldn’t be prouder of the progress we have made, with plenty of new features added in every major release. This includes major improvements to positioning including location tracking, integration of external GNSS receivers through not only Bluetooth but TCP/UDP and serial port connections, accuracy indicator and constraints, and most recently sensors reading to list a few.

We are now calling for the community to help further better QField and unlock an important milestone: background location tracking service.

Pledge now

Main goal: background location tracking on Android – 25'000€

Currently, QField requires users to keep their devices’ screen on and have the app in the foreground to keep track of the device’s positioning location. On mobile devices, this can drain batteries faster than many would want to, in environments where charging options are limited.

This crowdfunding aims at removing this constraint and allow QField - via a background service - to constantly keep tracking location even while the device is suspended (i.e., when the screen is turned off / locked).

To achieve this, a significant amount of work is required as the positioning framework on Android will need to be relocated to a dedicated background service. Recent work we’ve done adding a background service to synchronize captured image attachments in QFieldCloud projects armed us with the assurances that we can achieve our goal while giving us an appreciation of the large amount of work needed.

Some of the benefits

Running out of battery is the nightmare of most field surveyors. By moving location tracking to a background service, users will be able to improve their battery life considerably and keep focusing on their tasks even if it involves switching to a different app.

Furthermore, while OPENGIS.ch ninjas remain busy squashing reported QField crashes all year long, there will always be unexpected scenarios leading to abrupt app shutdowns, such as third-party apps, systems running out of battery, etc. To address this, the background service framework will also act as a safeguard to avoid location data loss when QField unexpectedly shuts down and offer users means to recover that data upon re-opening QField.

Stretch goal 1: background navigation audio feedback 5'000€

The second stretch goal builds onto QField’s nice fly-to-point navigation system. If the QField community meets this threshold, a new background navigation audio feedback informing users in the field of their proximity to their target will be implemented.

The audio feedback will use text-to-speech technology to state the distance to target in meters for a given time or distance interval.

Stretch goal 2: iOS 15'000€

The main goal will cover the Android implementation only. Due to being a very low level work we will have to replicate the work for each platform we support. If we reach stretch goal 2 we will also implement this for iOS.

Pledge now:

In case you do not see the embedded form you can open it directly here.

Thanks for supporting our crowdfunding and keep an eye on our blog for updates on the status.

The gift economy of Open Source is community driven and filled by folks with ideas that just go for it!

We at North Road are blessed that we get to join these creatives on their journey in order to get their products to you. Recently, the first QGIS flagship sponsor, Felt, engaged us to further strengthen their support for the up to 600,000 daily QGIS users to integrate their workflows between QGIS and Felt.

The result is the “Add to Felt” QGIS Plugin, which makes it super-simple to publish your QGIS maps to the Felt platform.

To get started, install the Add to Felt Plugin from the QGIS Plugin manager.

If you don’t have a free Felt account, you’ll need to sign up for one online (or from the Add to Felt plugin itself once you have installed it).

Within QGIS, users can easily publish their maps and layers to Felt. You can either:

• Publish a single layer by right-clicking the layer and selecting “Share Layer to Felt” from the Export sub-menu
• Publish your whole QGIS project/map by selecting the Project Menu, Export, “Add to Felt” action

Whilst Felt is loading up your map, you can continue working and it will let you know once your map is ready to open on Felt and share with others.

We are happy to let you know that the collaboration does not stop there! As with our SLYR tool, there is ongoing development as the requirements of the community and technology grow.  So install the Add to Felt Plugin via the QGIS Plugin manager, and let us know where you want it to go via the Add to Felt GitHub page.

Read more about it here:

• Felt’s Blog about the QGIS Plugin
• Installation Guide
• Getting Started for QGIS Users

• Peter Kimberley, Gradata Systems Pty Ltd, Canberra, Australia Vietnam War Missing in Action (MIA) Support
• HIdenori Watanave, The University of Tokyo, Tokyo, Japan, Digital Archives of War and Disasters
• Ethan Berg, Agora World, Philadelphia, PA, USA, GeoForAll: Simplifying 3D Geospatial Metaverse Creation

So there we go! Working together collaboratively with Lutra Consulting on another great addition to QGIS 3D Functionality thanks to Cesium Ecosystem Grants. Stay tuned on our social channels to find out when it will be released in QGIS.

Annotation and Graphic Layer Improvements

Text Annotations along Curves

For those working with curved annotations, we’ve got you covered! SLYR now supports the conversion of text annotations along curves in QGIS. With this enhancement, you’ll get accurate conversion of any curved text and text-along-line annotations from MXD and APRX documents. This has been a long-requested feature which we can now introduce thanks to enhancements coming in QGIS 3.32.

ArcGIS Pro Graphics Layer Support

SLYR now supports the conversion of ArcGIS Pro graphics layers, converting all graphic elements to their QGIS “Annotation Layer” equivalents. If you’ve spent hours carefully designing cartographic markup on your maps, you can be sure that SLYR will allow you to re-use this work within QGIS!

Enhanced Page Layout Support

Improved QGIS to ArcGIS Pro Conversions

New tools

The latest SLYR release introduces some brand new tools for automating your conversion workflows:

All these exciting additions to SLYR are available today to SLYR license holders. If you’re after one-click, accurate conversion of projects from ESRI to QGIS, contact us to discuss your licensing needs.

As described on our SLYR page, we also provide some of the conversion tools for free use via the SLYR “Community Edition”. We’re proud to announce that we’ve just hit the next milestone in the Community Edition funding, and will now be releasing all of SLYR’s support for raster LYR files to the community edition! This complements the existing support for vector LYR files and ESRI style files available in the community edition. For more details on the differences between the licensed and community editions, see our product comparison.