[Radiance-general] Sunlight hours calculation in radiance

[Giovanni Betti]

Thanks Lars, 
I see how that's a possibility but it would mean running separate images
and to filter each of them. 
It might work on a run over a day in winter but it seems unpractical
over a longer period of time (if you where to do this over a year you
would end up with about 4k images!) I was planning to run only one
simulation with multiple sun positions. Eventually as an optimization
the sun position can be clustereed according to tregenza patches and
each patch weighted based on the number of sun hours it represents (so
you don't even need 4000 sun but maybe only 300...)
Any hint on that?
Thanks,

Giovanni

-----Original Message-----
From: Lars O. Grobe [mailto:grobe at gmx.net] 
Sent: 15 February 2011 11:01
To: Radiance general discussion
Subject: Re: [Radiance-general] Sunlight hours calculation in radiance

Hi!

> The problem that I face is that each ray is weighted based on the
angle
> of incidence with the target surface. Is there a way of forcing
radiance
> to return only a yes/no type of value?

You may use pcomb to combine the images after applying a threshold to 
the pixel values (using the -e parameter to pass an expression) of each 
image.

Cheers, Lars.