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Hi I've never used any type of GIS software before so I'm trying to find out if it is suitable for what I'm trying to do:

I've written a c++ program which estimates ground level noise from a distant source as a function partially of distance.

There are three things I'm looking to be able to do from QGIS,

  • select a position in 3d space,
  • find the distance to the terrain below this point, and
  • plot the resultant noise onto the terrain.

Is this sort of functionality achievable without significant work? If so do you have any suggestions for what should be looked up in the docs?

Many Thanks

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semi-related:… – Simon Apr 5 '13 at 10:20

You could use GRASS GIS functionality for that through the GRASS toolbox extension of QGIS. See also

With v.distance you can calculate distances in 3D space.

share|improve this answer
Thanks for the reply. I've gone away and imported the Gridded height data (OS Merridian 2) with OSGB 1936 reference system but have trouble finding the lat/lon data for each point. i.e.I open the attribute table to see three columns FEATURE_SE, FEATURE_CO, and HEIGHT. I know the data loads correctly, produces the right map but don't know how to query the height at a position as I can't figure out how the Feature_se and feature_co link to lat/lon, or osgb references. Also should I convert the data to raster form as I want to be able to query height for any lat/lon. – wookie1 Apr 9 '12 at 16:15
I guess without a pointer to the data (structure) it will be hard to make suggestions... – markusN Apr 10 '12 at 18:28

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