[Radiance-general] solar radiation calculation

[Lars O. Grobe]

Hi Vincent,

if I would not know the difficulties to get a copy of it, I would ask
you to first browse through the book "Rendering with Radiance". If you
have access to it, this is the way to start. If not, I would advice you
to go through through the documentation done by Axel Jacobs (he made up
two great tutorials, if you cannot find the link I can look through my
bookmarks), which is available as pdf. After reading a bit, the first
thing you will understand is that actually the output you get from
radiance IS radiance (or irradiance which is most probably what you
need) as long as you do not convert it into photopic units. The easiest
way to divide the irradiance into diffuse and directed I could think of
would be to do a rendering with sun and sky and ambient calculation and
then substract the resulting pixel values of a rendering of only the sun
with ambient bounces = 0 (which is the direct component).

CU Lars.