| 1 |
greg |
1.1 |
{ RCSid $Id$ } |
| 2 |
|
|
{ LaFortune reflectance model with one lobe } |
| 3 |
|
|
|
| 4 |
|
|
{ Sample parameters (change these) } |
| 5 |
|
|
rho_d : 0.136465483630983; |
| 6 |
|
|
rho_s : 0.144594472775860; |
| 7 |
|
|
Cx : -0.605122636448704; |
| 8 |
|
|
Cy : -0.664960041454502; |
| 9 |
|
|
Cz : 0.586571000768196; |
| 10 |
|
|
n : 29.629194300125050; |
| 11 |
|
|
|
| 12 |
|
|
{ Useful functions } |
| 13 |
|
|
max(a,b) : if(a-b, a, b); |
| 14 |
|
|
abs(x) : if(x, x, -x); |
| 15 |
|
|
noneg(x) : if(x, x, 0); |
| 16 |
|
|
|
| 17 |
|
|
{ Normalization factor based on parameters } |
| 18 |
|
|
snf : (n+2)/(2*PI*max(abs(Cx),max(abs(Cy),abs(Cz)))^n); |
| 19 |
|
|
|
| 20 |
|
|
{ Note that we assume i and o vectors are normalized, both pointing away } |
| 21 |
|
|
|
| 22 |
|
|
lafortune(ix,iy,iz,ox,oy,oz) : if( -iz*oz, 0, |
| 23 |
|
|
rho_d/PI + rho_s*snf*noneg(Cx*ix*ox + Cy*iy*oy + Cz*iz*oz)^n ); |
