GIS for the Mac – gvSIG

Thanks Marcel St-Germain for turning me on to gvSIG v1.1. This relatively new open-source GIS software was reviewed by Adena Schutzberg All Points Blog on October 1, 2007 (and at its startup in 2005) and provides a quick review on the status of the project and major features. What I missed was the ability to run gvSIG on the Mac OSX operating system (Intel only) as well as Windows. Since I am now a MacBook Pro user (and lovin’ it), I am always on the prowl for good GIS applications that are low cost and robust. I mentioned in my review of My World GIS that most open source GIS for Mac (that are easy enough for me to have installed) are currently heavy on viewing capabilities but low on analysis. I am pleased to see that gvSIG is another GIS platform that runs on the Mac and includes a suite of analysis/geoprocessing capabilities.

Data File Types

This no-cost GIS platform seems well positioned for enterprise implementations due to its impressive ability to use vector (shp, dgn, dxf, dwg, gml, etc.), raster (ecw, mrsid, tiff, img, jpg2000, etc.), and it’s ability to connect with remote services like WMS, WFS, WCS, JDBC (geodatabases), catalogue, and gazetteer services (though maybe with a bit more development; there are some known problems that may merit holding off) . This likely stems from its government sponsorship by the “Conselleria de Infraestructuras y Transporte” (Council of Infrastructure and Transportation) of the “Generalitat Valenciana” (Regional Government of the Comunidad Valenciana in Spain) and its strong orientation to manage geographic information and towards Spatial Data Infrastructures (SDI).

Adding Your Own Data

Installation was easy. Even though a standard install file wasn’t available, it was easily created and I was up and running within about 60 seconds.

I’m one of those who dive right into a piece of software and then follow-up with the instructions if I can’t figure it out. While I didn’t find the interface immediately intuitive, MicroImages provides a good quick-start guide (January 2007 on version 1.0.1) that I found quite helpful for adding a WMS. Adding shapefiles and ArcIMS worked in much the same way. The gvSIG website states that most users of ArcView should find the interface intuitive. Unfortunately, its been a while since I’ve been on that platform.

Cartographic Features

Editing the symbology of layers was pretty straight forward. While the symbol sets are limited (small group of points and hatching), there appeared to be an option to add your own point graphics. Standard color ramps (swatches) and RGB menu ware available, as well as transparencies. Cartographic rendering options include display of unique values, intervals, and labeling with a similar interface to ArcGIS.

I probably missed it, but I didn’t see a print menu. Nonetheless, under VIEW>EXPORT users can export the map image to the following formats: JPG, BMP and PNG files.

Analysis

I was able to use the geoprocessing tools, but found them a bit buggy and slightly clunky (for example, I changed the map and measurement units before preforming a buffer operation, but they didn’t seem to stick). The following analysis functions are available, complete with graphic depiction and description (in English) of the function:

Proximity

-Buffer

-Spatial Join

Overlay

-Clip

-Difference

-Intersect

-Union

Computational Geometry

-Convex Hull

Aggregation

-Dissolve

Data Conversion

-Merge

-XY Shift

-Re-project

To support SDIs, future development would definitely benefit from the ability to re-project map data “on the fly.”

Overall I found the system impressive, though there may be a way to go on development and usability. It seems the team is well on its way and has the right support to make this a great open-source option for desktop and enterprise GIS.

Editing

While I haven’t tested it out yet, the system appears to have a full range of vector editing tools. Users can also create new layers. Users have the ability to export layers in shape, Oracle spatial, dxf, postGIS, GML raster and annotation.

Other Stuff

In addition to the MAC platform, at FOSS4G2007 the first migration of the gvSIG product (http://www.gvsig.gva.es) to mobile platforms was presented. This first launch is a brand-new open-source GIS client to be used in PDAs, with a good set of capabilities which fills a gap in the FOSS4G panorama, under a GPL license.

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The third gvSIG Conference will be celebrated the next November 14th, 15th, and 16th in the Valencia Conference Centre. Congrats to the entire gvSIG Team for the contributions they have made thus far. I’m looking forward to following its development.