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aquavitae
October 31st, 2007, 08:46 AM
Anyone using qgis for terrain modelling? This is my problem: I have to do a cut/fill exercise between two surcfaces. For anyone who doesn't know what I mean, I mean I have two surfaces, and I want to determine the positive and negative volumes between them. I don't know if this is possible in qgis, but if not I have other software that will do it, provided I can get the data in the right format. My source data is a dxf file containing contour lines (in 3d).

I'm fairly new to QGis so I don't really know where to start. I want to either use it to do the cut/fill if possible, or alternately use it to convert the dxfs into some ort of ascii xyz file.

Does anyone have any tips?

guano
November 22nd, 2007, 12:50 PM
Although QGIS is a nice GIS viewer, it doesn't have many analysis tools. You can try GRASS (grass.itc.it), which is very powerful. Also, QGIS can be used as a sort of graphical interface for GRASS.

aquavitae
November 23rd, 2007, 06:23 AM
Thanks for the reply. I though that would be the case, in fact when I said QGis I meant QGis including Grass... So how would you do it in grass? (preferably through qgis)