QGIS 3

Overview


QGIS is a free and open source geographic information system. QGIS 3 has been ported to support Python 3.

QGIS runs on all operating systems and offers you a choice between different releases. We recommend installing the long term release (LTR). Current LTR: QGIS 3.16 Hannover

You can download QGIS from here: https://www.qgis.org/en/site/forusers/download.html

Explore the following resources to get a grasp of the new features that QGIS 3 has to offer:

QGIS Documentation


Make sure to check out the User Guide and work through the Training Manual.

Desktop User Guide/Manual https://docs.qgis.org/3.16/en/docs/user_manual/index.html

Training Manual https://docs.qgis.org/3.16/en/docs/training_manual/

QGIS tutorials - Free Training Material https://qgis.org/en/site/forusers/trainingmaterial/index.html

 

Supported data formats


QGIS uses the OGR library to read and write vector data formats, including ESRI shapefiles, MapInfo and MicroStation file formats, AutoCAD DXF, PostGIS, SpatiaLite, Oracle Spatial and MSSQL Spatial databases, and many more. GRASS vector and PostgreSQL support is supplied by native QGIS data provider plugins. Vector data can also be loaded in read mode from zip and gzip archives into QGIS.

Refer to the section 13.3 Exploring Data Formats and Fields from the QGIS User Guide.

Loading data into QGIS can be done in several ways; following are the most common:

  • You can drag data directly from a folder (Windows OS) straight into the map

  • You can drag data from the Browser panel into the map

  • You can click Layer | Add Layer and choose what type of layer to add to the map

  • You can add datat through the Data Source Manager

You can find specific documentation on How to Load data in QGIS under the Guidance section.

 

Working with ESRI File Geodatabase in QGIS


Recent versions of GDAL and, therefore, GDAL-utilizing applications like QGIS are capable of efficiently reading and extracting information from file geodatabases.

GDAL now includes a very robust open source, read-only driver for the file geodatabase formatOpenFileGDB.  The driver's specifications indicate that this driver is capable of efficiently reading the contents of databases with large numbers of fields, without depending in any way upon proprietary software.  

 

QGIS 3 users can read file geodatabases by dragging the geodatabases, ending in the extension .gdb, directly into the Layers pane

Or Layer > Add Vector Layer

Select Directory as Source type, in Source choose Type = OpenFileGDB and navigate to the File Geodatabase you want to access and click Add.

Select All Layers and click OK.

 

The contents of the file geodatabase will appear in the Layers pane, and each layer can be exported to any other format with write support in GDAL, including the shapefile format.

 

An additional option for interacting with file geodatabases using GDAL is the FileGDB driver.  FileGDB depends upon Esri's File Geodatabase SDK, but it provides both read and write access to file geodatabases. Go to Guidance section to find specific documentation on how to install the FileGDB driver.

GeoPackage (.gpkg)


QGIS 3 has chosen GeoPackage as its default format. This is an open format, unlike the Shapefile, which is proprietary. GeoPackage also supports rasters. It is built on a SpatiaLite database, has no file size limitations, and works as one file. The format was developed by the Open Geospatial Consortium, you can find an exerpt of their definition below or the complete defintion of a GeoPackage here :

A GeoPackage is an open, standards-based, platform-independent, portable, self-describing, compact format for transferring geospatial information. The GeoPackage standard describes a set of conventions for storing the following within a SQLite database:

  • vector features

  • tile matrix sets of imagery and raster maps at various scales

  • extensions

To put it clearly, a GeoPackage is the SQLite container and the encodingstandard, GeoPackage governs the rules and requirements of the content stored in a GeoPackage container. The GeoPackage standard defines the diagram of a GeoPackage including table definitions, assertions of integrity, format limitations and content constraints. Thecontent required and taken in charge of a GeoPackage is entirely defined in thestandard. These features are reframed on a common basis and the extension mechanism provides to the developers a way to include additional features in their GeoPackages.

Explore the GeoPackage by watching a quick YouTube video.

Plugins


Plugins are a unique feature of QGIS. QGIS has been designed with a plugin architecuture. This allows many new features and functions to be easily added to the application. Plugins are available to be installed as you need them to enable further analysis. If what you want to do is not available within your current QGIS setup, search in the plugins as someone may have developed a tool to help you reach your solution.

For a list of all the available Plugins, including the latest and most popular, navigate to https://plugins.qgis.org/ Check out the most voted plugins: https://plugins.qgis.org/plugins/most_voted/

Labels


Smart labelling

The Label Toolbar, Labels tab of the Layer Styling or Layer Properties panel will allow you to customize your labels. Customization options include: Text, Formatting, Buffer, Mask, Shadow, Callouts, Placement and Rendering.

Try out the Follow Allong lesson on Labels from the QGIS Training Manual.

For a deep dive into lables check out this YouTube video from Klas Karlsson: QGIS User 0028 - All about Labeling

Placing labels manually

When you have overlapping labels, the traditional approach is either to generate annotations or alter the layer’s placement settings.

In QGIS3 you can just pick up and move labels! You can also hide, shift, and style single labels with the different tools included in the Label Toolbar.

Check out this quick YouTube video from burdGIS on how to Manually move labels in QGIS 3.

Handling Labels in Print Layout view

QGIS has a separate view called a Print Layout where map layouts can be constructed for print or pdf.

One of the new features in QGIS 3 is the ability to prevent map labels from hiding behind titles and other map surround objects on the print layout.

For any Map element the Items Properties will have a label icon control option.

Click on this icon to set up the label blocking properties. Under Label settings you will be able to select layout elements to block labels from appearing below them or control the placement of labels within an adjustable distance from the map’s edges or from any label-blocking items. Tick Show unplaced labels, to see which were not placed.

QGIS to Adobe Illustrator


You can bring your print layout into Adobe Illustrator either as a SVG or PDF file. Each method

Export as SVG

The benefit of using the SVG format is that the text remains 'text' (vs. paths) so it can be updated in Illustrator. But you will have to go create a Clipping Mask.

  1. Create a print layout

  2. Select Export as SVG

  3. Select where you want to store the SVG and give the SVG name.

  4. Select the following options in the Export panel

In Adobe Illustrator:

 

  1. Open the SVG file

  2. You will most likely need to clean up the layers a bit, getting rid of empty layers etc.

  3. Move the clipping path and the objects you want to mask into a layer or group.

  4. In the Layers panel, make sure that the masking object is at the top of the group or layer, and then click the name of the layer or group.

  5. Click the Make/Release Clipping Masks button at the bottom of the Layers panel or select Make Clipping Mask from the Layers panel menu.

 

 

 

Export as PDF

  1. Create a print layout

  2. Select Export as PDF

  3. Select where you want to store the PDF and give the PDF a name.

  4. Check the Export options you want to apply , you can also enable "Create Geospatial PDF", and click Save.

ESRI vs QGIS


QGIS compatibility with ArcGIS: both can handle the most common spatial data formats however QGIS consumes almost all types of data formats. In terms of functions extensibility, both QGIS and ArcGIS functionality can be extended through plugins and extensions respectively. Each software has support system through user community and ArcGIS has technical support system for its products. Read more>>

Comparison of GIS functions and which software is best suited

For a more detailed comparison follow the links below:

Advanced functions that can be done with QGIS rather than ESRI Advanced Licence.

Functions

QGIS

ArcMap

Erase: creates a feature class by overlaying the Input Features with the polygons of the Erase Features.

Use the geoprocessing tool Difference.

You can access it through Vector>Geoprocessing Tools> Difference

Erase tool only available with advanced license

Converting polygon features to point features

Convert the polygons to centroid points. Go to
Vector > Geometry Tools > Centroids.

Feature to Point is only available with advanced license.

For workaround with basic and standard license.

Zonal Statistics: calculates statistics on values of a raster within the zones of another dataset.

The most common function IMOs use this tool is to extract population density from WorldPop image by COD-AB

In QGIS, the Zonal statistics tool which is located under the Raster Analysis toolbox does a similar function just like the ArcMap

For a practical use example about the Zonal Statistics feature on QGIS, see the tutorial: Geospatial Population Analysis.

Spatial Analyst extension is needed to carry out zonal statistics functions.

 

Hill shading of Digital Elevation Models (DEM)

Most used to enhance three-dimensional appearance of reference maps.

QGIS allows to visualize elevation data as hill shade without the user needing to create a separate hill shade raster.

See tutorial

3D Analyst or Spatial Analyst extension needed to make hill shade raster.

Users need to calculate hill shade raster using the Hillshade tool.

Connect with QGIS community/ Finding help


The QGIS community offers a variety of different community-based support options.

Outputs/Resources


A useful beginner video