0.533000void brightfunc skyfunc2 skybright perezlum.cal010 1.382e+00 3.201e-01 1.066879 -0.754821 0.015485 -0.048998 -0.089403 0.066341 -0.860010 0.505947
The values in bold are then evaluated using the equations in the file perezlum.cal inside the RAYPATH directory in Radiance..
{ All-weather Angular Sky Luminance Distribution . Additional arguments required for calculation of skybright: A1 - diffus normalization A2 - ground brightness A3,A4,A5,A6,A7 - coefficients for the Perez model A8,A9,A10 - sun direction}skybright = wmean((Dz+1.01)^10, intersky, (Dz+1.01)^-10, A2 );wmean(a, x, b, y) = (a*x+b*y)/(a+b);intersky = if( (Dz-0.01), A1 * (1 + A3*Exp(A4/Dz) ) * ( 1 + A5*Exp(A6*gamma) + A7*cos(gamma)*cos(gamma) ), A1 * (1 + A3*Exp(A4/0.01) ) * ( 1 + A5*Exp(A6*gamma) + A7*cos(gamma)*cos(gamma) ) );
This data is then mapped to the "glow" material that represents the celestial hemisphere...You can edit the climate based sky produced by Honeybee and enter your own values. The other option would be to just use gendaylit from DOS Prompt.…
curve B
B1--------------------------B0
You define distances:
|A0 B0|
|A0 B1|
|A1 B0|
|A1 B1|
And find the smallest one. Then, based on the number of the shortest distance:
Flip A, Leave B
Flip A, Flip B
Leave A, Leave B
Leave A, Flip B
A more advanced metric would be to create all 4 blends, then pick the one that is shortest. Maybe that works better for what you want, maybe not.
--
David Rutten
david@mcneel.com…
Added by David Rutten at 8:09am on February 11, 2014