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I wrote this in qgis-user list but I'm forwarding for information.<BR>
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Cheers,<BR>
Luís Ferreira<BR>
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-------- Forwarded Message --------<BR>
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<B>From</B>: Luis Ferreira <<A HREF="mailto:Luis%20Ferreira%20%3clferreira75.1@gmail.com%3e">lferreira75.1@gmail.com</A>><BR>
<B>To</B>: <A HREF="mailto:qgis-user@lists.osgeo.org">qgis-user@lists.osgeo.org</A><BR>
<B>Subject</B>: Re: [Qgis-user] Inter-visibility analysis<BR>
<B>Date</B>: Fri, 30 Mar 2012 15:57:07 +0100<BR>
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<PRE>
Not that I know.
r.viewshed works relatively fast, with lat long support and the very
useful option of target ground offset, but with the limitation of one
pair of observer coordinates per run. Probably, you can make a script to
read a list of observer coordinate pairs and, using r.mapcalc, integrate
the obtained viewsheds.
<A HREF="http://grass.osgeo.org/wiki/GRASS_AddOns#r.viewshed">http://grass.osgeo.org/wiki/GRASS_AddOns#r.viewshed</A>
r.viewshed it is on trunk, already.
Extending r.viewshed to read vector (point, line or polygon objects
converted to raster?), using multiple locations for viewshed
determination, and the the option to calculate the relative
observability (0.0-1.0) of each resulting surface pixel, will be very
useful. Probably r.cva solves this, I didn't use r.cva yet.
<A HREF="http://grass.osgeo.org/wiki/GRASS_AddOns#r.cva">http://grass.osgeo.org/wiki/GRASS_AddOns#r.cva</A>
Luís Ferreira
On Sex, 2012-03-30 at 15:42 +0200, Julian Bogdani wrote:
> Hello,
> I've been use qgis for a while and I'm starting now with GRASS, too.
> I'm interested in building a inter-visibility map using a point
> shapefile and a DEM. QGIS has a plugin for viewshed, and I tried LOS
> in GRASS which works wonderfully, for a single point of observation.
> Is there a way to get lines linking sites that are visible from each
> other?
>
>
> Thank you
>
>
>
> -----
> Julian Bogdani
> <A HREF="http://bradypus.net">http://bradypus.net</A>
>
>
>
>
>
>
>
>
>
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