[GRASSLIST:5865] Re: Help with polygons

[Moritz Lennert]

> Well from earlier questions that have gone unanswered -  I guess no one is
> using grass with digitizing tablets.  So I will try another tack.  I want
> to
> use Grass in preference to ArcView, MapInfo, ...  but have one
> all-consuming
> issue.  How to make polygons.  Thought I had it when I explored v.in.dxf.
> Unfortunately Grass does not make polygons out of dxf files only line or
> point features.  Have been trying to find a way in Grass to convert closed
> polylines to polygons using v.support and v.build.polylines.  No luck so
> far.  Have spent way too much time searching the web and going over man
> pages.
>
> Don't have much hair left to pull out.  Can anyone suggest a method to
> make
> polygons in Grass or in files imported from Cad programs??

In the GRASS ascii vector file all that distinguishes lines from polygons
are the 'L', respectively 'A' label. So "all" you have to do is change
those. There is a script in GRASS called v.line2area which should be able
to do this for you.

Moritz