1 |
greg |
1.6 |
{ RCSid $Id: klems_quarter.cal,v 1.5 2015/03/27 18:58:06 greg Exp $ } |
2 |
greg |
1.1 |
{ |
3 |
greg |
1.2 |
Compute interior bin for quarter Klems BSDF basis (0-40) |
4 |
greg |
1.1 |
Returns -1 for wrong-side rays |
5 |
|
|
|
6 |
|
|
Modified from klems_full.cal |
7 |
|
|
|
8 |
|
|
7/18/2014 G. Ward |
9 |
|
|
} |
10 |
|
|
DEGREE : PI/180; |
11 |
|
|
Acos(x) : if(x-1, 0, if(-1-x, PI, acos(x))) / DEGREE; |
12 |
|
|
posangle(a) : if(-a, a + 2*PI, a) / DEGREE; |
13 |
|
|
Atan2(y,x) : posangle(atan2(y,x)); |
14 |
|
|
|
15 |
greg |
1.6 |
kqpola(r) : select(r, 9, 27, 45, 63, 90); |
16 |
greg |
1.3 |
kqnaz(r) : select(r, 1, 8, 12, 12, 8); |
17 |
greg |
1.1 |
kqaccum(r) : if(r-.5, kqnaz(r) + kqaccum(r-1), 0); |
18 |
|
|
kqfindrow(r, pol) : if(r-kqpola(0)+.5, r, |
19 |
|
|
if(pol-kqpola(r), kqfindrow(r+1, pol), r) ); |
20 |
|
|
|
21 |
|
|
kqazn(azi,inc) : if((360-.5*inc)-azi, floor((azi+.5*inc)/inc), 0); |
22 |
|
|
|
23 |
|
|
kqbin2(pol,azi) = if(pol-90, -1, |
24 |
|
|
select(kqfindrow(1, pol), |
25 |
|
|
kqazn(azi,360/kqnaz(1)), |
26 |
|
|
kqaccum(1) + kqazn(azi,360/kqnaz(2)), |
27 |
|
|
kqaccum(2) + kqazn(azi,360/kqnaz(3)), |
28 |
|
|
kqaccum(3) + kqazn(azi,360/kqnaz(4)), |
29 |
|
|
kqaccum(4) + kqazn(azi,360/kqnaz(5)) |
30 |
|
|
) ); |
31 |
|
|
|
32 |
greg |
1.5 |
RHS = 1; { set to -1 for left-handed system } |
33 |
|
|
|
34 |
greg |
1.1 |
kqbin(Nx,Ny,Nz,Ux,Uy,Uz) = kqbin2(Acos(-Dx*Nx-Dy*Ny-Dz*Nz), |
35 |
greg |
1.4 |
Atan2(-Dx*Ux-Dy*Uy-Dz*Uz + (Nx*Dx+Ny*Dy+Nz*Dz)*(Nx*Ux+Ny*Uy+Nz*Uz), |
36 |
greg |
1.5 |
-RHS*(Dx*(Uy*Nz-Uz*Ny) + Dy*(Uz*Nx-Ux*Nz) + Dz*(Ux*Ny-Uy*Nx)))); |
37 |
greg |
1.1 |
|
38 |
|
|
Nkqbins : kqaccum(kqnaz(0)); { Number of bins for one elevation } |