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Hi Andrea,<br>
Thanks for your message. But what is the ground plane ? r.horizon
use the topography, so nothing is plane (and the earth curvature
tends to lower the ground). I guess as the calculation is done at
ground level, the minimum viewable horizon cannot be lower than
zero. The calculation should be done higher than ground level to
"see" negatives horizon. Never mind I will try to create my own
r.horizon with r.transect or r.profile.<br>
Best regards,<br>
Frank<br>
<br>
<div class="moz-cite-prefix">Le 30/07/2018 à 08:47,
<a class="moz-txt-link-abbreviated" href="mailto:balotti.and@gmail.com">balotti.and@gmail.com</a> a écrit :<br>
</div>
<blockquote type="cite"
cite="mid:71401a24-864c-09b0-3710-3634f9f001e8@gmail.com">Hi
Frank,
<br>
just my opinion but r.horizon I suppose is targeted to solar
radiation modules and because of that returns only the
line-of-sight "obstacles" above the ground plane, where direct
sunlight may be obstructed by obstacles.
<br>
best regards,
<br>
<br>
Andrea Balotti
<br>
<br>
Il 28/07/2018 15:59, Frank David ha scritto:
<br>
<blockquote type="cite">Dear all,
<br>
<br>
It seems that r.horizon in does not return negative heights. How
it's possible in case of the given point from the calculation is
done is located on mountain and the horizon around is below zero
??. I miss something may be...
<br>
<br>
Thank you for your explanations
<br>
<br>
Regards
<br>
<br>
Frank
<br>
<br>
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