[GRASS-user] Distance layer

[Dylan Beaudette]

On Friday 27 October 2006 09:28, Moritz Lennert wrote:
> Nomad Rain wrote:
> > Hello GRASS group!
> >
> > Currently  I  try  to  make  an  environmental  application - a script
> > implementing  one  of  the  atmospheric polution models. The algorithm
> > demands  to  include the function which returns the value depending on
> > distance from the polution source.
> >
> > Thus,  I want to calculate the layer of distances (first map) from the
> > only pollution source (point on second map).
> >
> > I cannot find the command which can automaticaly return the value of
> > distance between two pixels on two maps.
> >
> > Does anybody know how to do it (find the distance betw. 2 pixels)?
> >
> > I use grass-6.2.0RC2
>
> r.distance ?
>
> There was some discussion about a potential problem with r.distance
>
> http://grass.itc.it/pipermail/grass5/2006-October/026333.html
>
> Markus Neteler wrote:
> > r.distance happily calculates the distance even if
> > one object is within the other
>
> Moritz

There was: but only in the case of pixel_1 being contained by raster_zone_2 . 
There was a proposed patch by jachym, but not sure about its status.

A raster/vector approach with r.cost might give you more flexibility.

In fact, this might have been the module that came to mind when i first 
replied... its early here ;)

Cheers,

-- 
Dylan Beaudette
Soils and Biogeochemistry Graduate Group
University of California at Davis
530.754.7341