Beginner's Guide: Open Source Desktop Mapping Software Review

By Erin Porter

GIS (geographic information system) mapping and visualization software has incredible potential to help us analyze large datasets and understand the world around us. GIS desktop applications range in capabilities, features, tools, and even price, making the selection of a single GIS desktop application challenging and frustrating if you are new to the world of GIS software. Open source software - where the developer has released the software under a license that grants others the right to use, change, and distribute the software (i.e. FREE TO USE) - is a great place to start. This article outlines and compares three open source desktop GIS software applications: QGIS, gvSIG, and SAGA GIS. Also included is a review of Google Earth Pro. Although Google Earth Pro is free to use, it is not available under an open source license. Some considerations for choosing a GIS software application:

• How much time will it take to learn the software?

• Is the software being maintained for the foreseeable future?

• What is the license type for the software? Are there restrictions to my use of the software? If so, what are they and will they prevent me from completing the work I am trying to do?

• How easy/difficult is it to install?

• How complex is my project? Does this software have the tools I need to complete my project?

• Does the software allow me to share and/or print my files and projects? Will others need the same program to open those files?

Introduction of 3 Open Source GIS Options

First up we have QGIS, previously known as Quantum GIS, a project of the Open Source Geospatial Foundation (OSGeo) initially released in 2009. The software has since gone through several iterations with the help of a dedicated community of volunteer developers who regularly release bug fixes and develop new functionality. QGIS is probably the most widely used and recognized of the applications reviewed here and has some of the most robust documentation and tutorials on the QGIS website and beyond - not to mention the fact that QGIS has been translated into nearly 50 languages. User communities and forums also offer a great resource for trouble-shooting issues and sharing resources. In addition, user-created plug-ins offer additional functionality within QGIS. Anyone can create and publish a plug-in, resulting in continuous growth of QGIS tools available to users. As of the writing of this article, the GIS Stack Exchange had 26,697 questions tagged [qgis] and hundreds more relating to QGIS plugins and extensions. This is evidence of a strong community that will continue to upgrade QGIS and provide support to users.

gvSIG is structured along the lines of other similar GIS software applications and shares many of the same basic tools and mapping capabilities. This software was developed in 2004 as part of a project for Generalitat Valenciana ( hence the gv in gvSIG) in Spain for the Valencian Regional Government. Like QGIS, gvSIG is now managed by OSGeo which claims that the software is “the ideal tool for users working in the land realm” due to its array of tools geared towards working with geographic information. Because gvSIG was developed with Spanish users in mind, much of the documentation and tutorials are in Spanish, though you can usually find the English equivalent with a bit of digging. Part of what makes gvSIG so useful as a GIS tool is the ability to install additional add-ons for specific functions and analytics. In addition to the official gvSIG list of add-ons, the gvSIG user community creates and maintains many additional add-ons that allow manipulation and visualization of data beyond the basic functionality.

SAGA (System for Automated Geoscientific Analyses) GIS was originally developed at Goettingen University in Germany with the development objectives: “To give geo-scientists an effective but easy to learn tool for the implementation of geoscientific methods” and “To make these methods accessible in a user-friendly manner.” Of the software applications reviewed in this article, SAGA is perhaps the most technical in nature and difficult to learn as a beginner. Although SAGA’s user interface has the same feel as other mapping software, the program differs in that more advanced functions are organized into modules in framework-independent Module Libraries accessed through the user interface or with shell scripts, Python, etc. SAGA is structured with science fields in mind, so data analysis and graphical visualization modules are structured to be used alongside SAGA’s mapping functionality. In fact, the module system allows SAGA to run multiple functions at the same time without creating changes to all parts of the project.

Bonus: Google Earth Pro

I include Google Earth Pro as an additional desktop software here because it has been free to use since 2016. However, Google Earth Pro is not released under an open source license which means that Google still controls the application. So far, Google has continued to maintain and develop Google Earth Pro into a powerful, easy-to-learn tool for basic mapping and visualization projects. Google has stated that they will continue to maintain Google Earth Pro while they add functionality to the web version. Google Earth Pro provides access to a wealth of Google data and imagery. Perhaps Google Earth’s greatest potential lies in the software's high-resolution satellite imagery and ability to view the Earth's surface and landscape in three dimensions. You can even view historical imagery of an area (dependent upon available data) that allows you to track changes over time. Users also have access to Google’s Street View functionality, allowing you to see on-the-ground conditions from the comfort of your computer screen. Google’s search engine technology comes in handy when navigating to specific areas of the map - a country, state, town, or even monument or building name will navigate to your area of interest.

Review

In order to test each of these software programs, I tried creating a basic map of the bicycle routes and camping areas in my home state of Minnesota and then compared the experience across programs. This review is meant for GIS beginners, so I did not dive into more advanced functionality. Instead, I looked at key basic features and functionality of each software application. These included:

• Installation

• User interface and ease of user experience

• Opening files

• Styling

• Labeling

• Editing

• Saving and file formats

Considering the complexities of learning the SAGA GIS desktop software, I have chosen not to include the program in the following analysis. However, if you are interested in a GIS program with more advanced analysis or data visualization potential, consider doing some additional research into SAGA GIS.

Also please note that functionality is constantly being added to QGIS and gvSIG and functionality not available according to this chart may be added in the future.

While creating my test map in each application, I also tried creating an elevation profile as this can be tricky and time-consuming. Both QGIS and gvSIG create elevation profiles from DEM data layers using a profile tool - an add-on for both programs. Google Earth Pro easily creates a profile using points and a line designated by the user without installing any additional tools. Paired with the high-resolution imagery in Google Earth Pro, this is a helpful and powerful tool for beginners.

Selecting the right GIS software comes down to what you are hoping to achieve with your project. From a beginner's perspective, I found Google Earth Pro to be the easiest and most intuitive program to learn. The software would be a great option for anyone looking to test the waters of mapping software with a simple mapping project or as an easy and quick way to view GIS data. Google Earth Pro is a great tool for viewing GIS data and exploring aerial imagery, but has serious limitations in regards to editing data attributes and data analysis. Compared to QGIS and gvSIG (or SAGA), Google Earth Pro's functionality is aimed at users with basic data creation and analysis needs.

If you have more time to spend learning a software application and are looking for a reliable general mapping tool, I would recommend QGIS. The user and developer community surrounding QGIS is extremely helpful, and most (if not all) tools have ample documentation that is free to access. Connections between the QGIS and ArcGIS/Esri community continue to make it easier to view and manipulate data in and produced by both QGIS and Esri applications. Furthermore, QGIS’s user interface and editing capabilities appear to outperform those of the other programs reviewed here, especially for beginner GIS users.

Experienced users with some background in GIS software and more specialized needs in geographic data analysis or geoscience data analysis and visualization may want to consider exploring gvSIG or SAGA.

If you’re curious and want to learn more about your mapping options, call us at (833) 254-6345 or send us an email at contact@line-45.com to schedule a free consultation.