Over the course of 2009, I got involved with OpenStreetMap. If you haven’t used OSM, I suggest you check it out. It’s being updated and used throughout the world, from mapping campuses in New Jersey to aiding the relief efforts in Haiti.

So, duExample from OSM of the imported land use polygons around Trenton, NJ.ring 2009, I had noticed that on OSM, the State of Georgia had land use data. I started to look into how Georgia was so lucky. OSM relies on user contributions, so some savvy user must have added all of those polygons to the map. I contacted that savvy user to find out more. Liber pointed me to some of the methods he and others have used to import GIS data into OpenStreetMap. I was unsatisfied with the existing software, so I looked into the OSM API and wrote my own code to export directly from ArcGIS into the .osm file format.

ExportToOSM.py is my crack at programming an export utility. I wanted something that would export multipolygons from ArcGIS as OSM multipolygon relations and would produce a file free of redundant nodes. I used an earlier version of my script to export the buildings on Rowan’s campus. After fixing a few issues – namely the multipart polygons (take a look at Evergreen Hall, still need to punch in the interior courtyard as a doughnut hole) – I began developing a plan to export NJ’s 2002 Land Use data to OSM.

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