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I want to export the boundaries of a parcel to my GarminMap 60CSx. I downloaded a parcel map from the county, and I want to use it to walk the perimeter.

Does the .gpx format support polygons? Or is there some other way?

I'm on Mac, using QGIS 1.7.4.

AndreJ
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Gray Shaw
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  • I have the same problem I can't Import or export .GPX file to my gpsmap 62s, I suceed to take back the .gpx and register it with basecamp and after work on it with Qgis but I still don't succed to transfert the .gpx to my gps. Did you found a solution? Thanks for your answer! Julien Brach –  Sep 17 '13 at 00:55

2 Answers2

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No, the GPX driver of GDAL which is used by Qgis for Save As does not know how to handle polygon geometries, and throws an error.

But you can convert the polygon into a line geometry using Vector->Geometry-Tools->Polygon to line, and export the resulting new shapefile to GPX.

Most probably you want to add FORCE_GPX_TRACK=YES in the layer creation field, and check Surpress attribute creation.

And make sure the export CRS is EPSG:4326, that is WGS84 latlon.

AndreJ
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  • I successfully created a new shapefile and saved the layer as a .gpx (following all your instructions), but Garmin BaseCamp rejects it as an invalid .gpx file. I peeked into the file and saw delimiters but no numbers. What should I try next? – Gray Shaw Nov 20 '12 at 10:44
  • Can you import the gpx to Qgis with GPX tools? Perhaps you can share part of the gpx file here? – AndreJ Nov 20 '12 at 10:52
  • I was mistakenly using a database program to view the gpx file. In a text viewer, the numbers are there. – Gray Shaw Nov 20 '12 at 16:30
  • Importing the gpx to QGIS results in a blank map. – Gray Shaw Nov 20 '12 at 16:31
  • ...etc. – Gray Shaw Nov 20 '12 at 16:33
  • Oops, the coordinates are not WGS84 latlon. When exporting, you have to choose EPSG:4326. GPX does not accept any other coordinate system. – AndreJ Nov 20 '12 at 16:43
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One option is to create a KML overlay. I can't specifically remember how to do it manually. Basically, it's a zip file with an internal folder structure to house images. There's also an XML file involved which maps the images to the project space.

I collaborated on an ArcExplorer plugin to do the heavy for this. I realize you're on a Mac and this isn't really helpful, but you can browse the source to see what I'm doing.

https://bitbucket.org/TheGeoist/garmintools_csharp

Check out CreateProjectFolder, CreateTile and WriteHeader

EDIT: Acutally, from memory, the 60CSx doesn't support kml overlays. You might be better off exporting the SHP to GPX in QGIS, then uploading the boundaries to the device.

nagytech
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