[GRASS-dev] [r.sun]

[Markus Neteler]

On Thu, Apr 28, 2016 at 2:51 PM, Ben Hur Pintor <bnhr.dev at gmail.com> wrote:
>> Long time back I added the SOLPOS support in r.sunmask.
>> Do you have a pointer to the SPA source code? Because implementing it
>> from a 40 pages PDF is expensive :-)
>
> Sorry about that. Hahaha. Here's the actual C code:
> https://www.nrel.gov/midc/spa/

"... The Software is being provided for internal, noncommercial
purposes only and shall not be re-distributed. ..."

Unfortunately it is non-free.

>> You may consider to tile the data (r.tile) with sufficient overlap,
>> then process these tiles in parallel.
>
> I was choosing between r.tile or simply setting smaller computational
> regions.

Fine but be sure to not leave out shadow relevant relief in case you
are in a hilly / mountainous area.
r.viewshed can help to some extent to figure out how large the region
needs to be.

Markus

-- 
Markus Neteler
http://www.mundialis.de - free data with free software
http://grass.osgeo.org
http://courses.neteler.org/blog