| 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 |
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| 12 |
{ Useful functions } |
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max(a,b) : if(a-b, a, b); |
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abs(x) : if(x, x, -x); |
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noneg(x) : if(x, x, 0); |
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{ Normalization factor based on parameters } |
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snf : (n+2)/(2*PI*max(abs(Cx),max(abs(Cy),abs(Cz)))^n); |
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{ Note that we assume i and o vectors are normalized, both pointing away } |
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| 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 ); |
