[GRASS-user] Extracting from 2D to 3D

[Markus Neteler]

Charles,

On Sat, Aug 23, 2008 at 10:38 PM, charles <eriseres at airpost.net> wrote:
> Hello all,
>
> I have purchased to book, Open Source Grass, the third edition and wanted to
> experiment with 3D vectors using nviz.  I have followed the commands in the
> book, page 209/210 but can not display the 3D vectors in nviz.  Is there an
> update to the commands or can anyone describe to me what I am doing wrong.

indeed, there is an extra step needed: the lines in the DXF files need to
be converted to boundaries and then centroids have to be added.
v.extrude will change otherwise the lines simply to 3D lines.

I have posted a correction at:
http://www.grassbook.org/errata_menu3rd.php

Then nviz shows the 3D house blocks.

Thanks for bringing this up,
Markus