The participants in this project use a variety of open source and/or commercial desktop GIS software packages. For at least four of the participating entities (three local units of government and one NGO), the tools of choice are the open source packages Quantum GIS (QGIS) and uDig. One of the townships is fortunate enough to maintain an ArcGIS license, so that township uses ArcMap and ArcCatalog for GIS data product creation. Another makes good use of free tools available from Google, namely the utilities and API's contained within Google Earth and Google Maps.
One common drawback to open source desktop GIS packages at this time is their inability to open more than one map window in their map print composers. If the final map product requires one or map insets in addition to the main map, then more than one instance of the GIS software must be used to create the insets. A graphic layout software package such as Inkscape, QuarkExpress or PhotoShop can then be used to create the final map layout and decorations.
Quantum GIS (QGIS)
Given that the major GIS need of the participating townships is the production of data and mapping products for their statutory planning and administrative functions, the choice of desktop GIS tools narrows to more vector-oriented, easy-to-use, and map layout-oriented products.
Some of the vector-oriented, open source desktop GIS tools familiar to students of Penn State's MGIS program include uDig and QGIS. These two packages fall squarely within the areas of appropriateness for the “Intermediate” and “Experienced” user personas from the Sherman (2008) and Steiniger and Hay (2009) tables reproduced previously in the Open Source Desktop GIS subsection.
The paper by Steiniger and Hay ( 2009) notes map layout and production as a common weakness in open source desktop GIS tools. While this was true at the time of publication of the paper, the current incarnations of QGIS (2.8 at the time of this edit) have vastly increased the package's map composition, styling, and publication capabilities. Some reviewers have gone so far as to venture that some of the capabilities now exceed those available in the leading industry-standard brand.
![]() Again, if the map layout requirements exceed the capabilities of QGIS' Print Composer module, the map data window can easily be exported as a graphic file (usually as a vector SVG file, but often as raster files), which in turn can be laid out and finished using an open source graphics/layout software such as Inkscape, GIMP, and Paint.NET (or their commercial counterparts). Inkscape and its commercial alternatives appear to be the favorite tools for final touch-up work.
Being an open source, standards-compliant package, QGIS can read, convert, and manipulate a very large variety of vector and raster data formats, including open source datastores such as PostGIS and SpatiaLite.
Another advantage of QGIS is its general popularity in the open source GIS community. This ensures that more support for this product exists than is usual for open source products. There are numerous on-line documents, several on-line forums, tutorials both in web page and video formats, and even one book that has been published. (See Resources subsection.)
A screenshot of a GIS map project on QGIS 1.7 is shown above right.
The other desktop GIS for this project is the User-friendly Desktop Internet GIS (uDIG) package . This elegant program was not originally intended to form part of the desktop GIS toolkit for the project. It was always earmarked for use in the web mapping component of this project for some of its other capabilities. (See the Open Web Mapping and Workflows subsections that follow.)
Soon after the start of the project, it became apparent that a serious problem currently exists in using most open source desktop GIS packages here in our state of Michigan. This relates to the use of the Michigan GeoRef map projection by the state GIS data clearinghouse (Michigan Center for Geographic Information) for its publicly-available data layers. The open source GDAL/OGR utilities (see section below) apparently have some issues in correctly handling this projection, which is an instance of the class of map projections known as the Hotine Oblique Mercator. This problem and the use of uDig as part of the workaround is described in the Project Tutorials subsection.
![]() uDig also plays an important role in the workflow for creating an open web map that uses the open source GeoServer software for serving maps and other files. See the Open Web Mapping section.
The figure at left shows a typical uDig screen.
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