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I have a problem regarding GPX tracks that were created from Shapefiles using QGIS.

The shapefiles were created by selecting all parts of a route from a PostGIS database. The polylines were merged with QGIS and then exported as a GPX file by using the 'Save as' option.

The resulting GPX files look like this:

<?xml version="1.0"?>
<gpx version="1.1" creator="GDAL 1.11.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ogr="http://osgeo.org/gdal" xmlns="http://www.topografix.com/GPX/1/1" xsi:schemaLocation="http://www.topografix.com/GPX/1/1 http://www.topografix.com/GPX/1/1/gpx.xsd">
<metadata><bounds minlat="51.533449555703989" minlon="6.983701320292362" maxlat="51.554475633460669" maxlon="7.010408625662222"/></metadata>

<trk>
<extensions>
<ogr:OBJECTID>31751.0</ogr:OBJECTID>
</extensions>
<trkseg>
<trkpt lat="51.54792023947288" lon="6.986589223144231">
</trkpt>
<trkpt lat="51.547997675144856" lon="6.986820893755352">
</trkpt>
<trkpt lat="51.548138136988818" lon="6.986910766789045">
</trkpt>
<trkpt lat="51.548352505219341" lon="6.987013118209317">
</trkpt>
<trkpt lat="51.549051234512156" lon="6.987331861261017">
</trkpt>
</trkseg>
<trkseg>
<trkpt lat="51.54792023947288" lon="6.986589223144231">
</trkpt>
<trkpt lat="51.547840418735099" lon="6.986046522387352">
</trkpt>
<trkpt lat="51.547799254904852" lon="6.985851100932796">
</trkpt>
<trkpt lat="51.547750380482739" lon="6.985724171010038">
</trkpt>  

And so on. There are 8 segments of the track in total.

The issue is that while some web applications are able to display this track without a problem (like http://www.gpsvisualizer.com/)

Displayed using GPS Visualizer

many others are not (http://www.maplorer.com/view_gpx.html ) Displayed using maplorer

I have already tried adding timestamps to the points, but that didn't change anything.

I assume that the issue has something to do with the segments because if I merge all segments of the track using the GPX_Editor from Sourceforge the route gets distorted exactly like it does in the maplorer example. No matter what application i use, the track is either displayed correctly as in the first example or falsely like in the second example.

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It might be that false displaying applications don't respect <trkseg> correctly.

If you add </trk><trk> to every trkseg change, it might come out correct.

Otherwise you have to create a new GPX file for every <trkseg> using one trkseg per track and file.

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