| 13 |
|
A5,A6,A7 - sun direction |
| 14 |
|
} |
| 15 |
|
|
| 16 |
+ |
cosgamma = Dx*A5 + Dy*A6 + Dz*A7; |
| 17 |
+ |
|
| 18 |
+ |
gamma = Acos(cosgamma); { angle from sun to this point in sky } |
| 19 |
+ |
|
| 20 |
+ |
zt = Acos(A7); { angle from zenith to sun } |
| 21 |
+ |
|
| 22 |
+ |
eta = Acos(Dz); { angle from zenith to this point in sky } |
| 23 |
+ |
|
| 24 |
+ |
wmean(a, x, b, y) : (a*x + b*y) / (a + b); |
| 25 |
+ |
|
| 26 |
|
skybr = wmean((Dz+1.01)^10, |
| 27 |
|
select(A1, sunnysky, cloudysky, unifsky, intersky), |
| 28 |
|
(Dz+1.01)^-10, A3); |
| 29 |
|
|
| 20 |
– |
wmean(a, x, b, y) = (a*x + b*y) / (a + b); |
| 21 |
– |
|
| 30 |
|
sunnysky = A2 * (.91 + 10*exp(-3*gamma) + .45*cosgamma*cosgamma) |
| 31 |
|
* if( Dz - .01, 1.0 - exp(-.32/Dz), 1.0) / A4; |
| 32 |
|
|
| 37 |
|
intersky = A2 * ( (1.35*sin(5.631-3.59*eta)+3.12)*sin(4.396-2.6*zt) |
| 38 |
|
+ 6.37 - eta ) / 2.326 * |
| 39 |
|
exp(gamma*-.563*((2.629-eta)*(1.562-zt)+.812)) / A4; |
| 32 |
– |
|
| 33 |
– |
cosgamma = Dx*A5 + Dy*A6 + Dz*A7; |
| 34 |
– |
|
| 35 |
– |
gamma = Acos(cosgamma); { angle from sun to this point in sky } |
| 36 |
– |
|
| 37 |
– |
zt = Acos(A7); { angle from zenith to sun } |
| 38 |
– |
|
| 39 |
– |
eta = Acos(Dz); { angle from zenith to this point in sky } |
