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Does anyone have a simple work-flow for drawing cross sections of earth features in QGIS?

My thing is that QGIS is being used to present the plan view, but we have a little interest in some elevations as well. All the data is one set and is simply an elevation value in the attribute table, I don't want to have to move all that to CAD.

One logical workaround is to present the z value as the y.

I am a dunce in paper space in CAD, and would be more comfortable with the QGIS Composer.

PolyGeo
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Willy
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  • I'm guessing you want to do it on a vector layer? – Nathan W Jul 21 '12 at 01:01
  • I think so, probably anything that is convenient to use in Composer. – Willy Jul 21 '12 at 01:04
  • I got going with Excel and some lines in a chart. Once set up I knocked off 6 in 3 hrs. I pasted the crossections pngs at the bottom of the map in QGIS MAP Composer, quite happy in the end. – Willy Jul 21 '12 at 11:44

1 Answers1

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First you have to use a DEM, then you have to have installed the terrain profile plugin. Once is active, all you have to do is draw a line over your DEM and the plugin will calculate the profile. A nice thing is that you can play with the vertical exaggeration and also that you can export the profile as a PDF. A minor thing is that the drawing tool of the plugin only allows you trace a straight line...Git it a try!

Gerardo Jimenez
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  • Hmm, tried to get the data into a format for a dem, not suitable for that. – Willy Jul 21 '12 at 04:06
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    Is this because your elevation data is too thin to let you make a meaningful DEM? How about using an SRTM DEM together with the 'profile from line' plug-in. Nick. – nhopton Jul 21 '12 at 08:20
  • The elevation data is from two sources, a DGPS survey of points, and from a CAD file containing developed survey data including contours. So it is all vector data. – Willy Jul 21 '12 at 11:41
  • If your contours have elevation values you can build a dem using the interpolation plugin. The you can use the terrain profile plugin – Gerardo Jimenez Jul 22 '12 at 00:56