| 2 |
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{ LaFortune reflectance model with N lobes } |
| 3 |
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| 4 |
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{ Sample parameters (change these) } |
| 5 |
< |
rho_d : 0.136465483630983; |
| 6 |
< |
rho_s(i) : select(i, 0.144594472775860); |
| 7 |
< |
Cx(i) : select(i, -0.605122636448704); |
| 8 |
< |
Cy(i) : select(i, -0.664960041454502); |
| 9 |
< |
Cz(i) : select(i, 0.586571000768196); |
| 10 |
< |
n(i) : select(i, 29.629194300125050); |
| 5 |
> |
rho_d : 0.017615787130711; |
| 6 |
> |
rho_s : 0.654729812719232; |
| 7 |
> |
Cx(i) : select(i, -0.75, -0.78); |
| 8 |
> |
Cy(i) : select(i, -0.91, -.81); |
| 9 |
> |
Cz(i) : select(i, .75, .83); |
| 10 |
> |
n(i) : select(i, 30, 15); |
| 11 |
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NL : n(0); |
| 12 |
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| 13 |
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{ Useful functions } |
| 14 |
– |
max(a,b) : if(a-b, a, b); |
| 14 |
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abs(x) : if(x, x, -x); |
| 15 |
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noneg(x) : if(x, x, 0); |
| 16 |
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| 17 |
< |
{ Normalization factor based on parameters } |
| 17 |
> |
{ Normalization factor based on parameters } |
| 18 |
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snf(i) : (n(i)+2)/(2*PI*max(abs(Cx(i)),max(abs(Cy(i)),abs(Cz(i))))^n(i)); |
| 19 |
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| 20 |
< |
{ CHANGE THE FOLOWING TO MATCH NL } |
| 21 |
< |
snfk(i) : select(i, snf(1)); |
| 20 |
> |
{ CHANGE THE FOLOWING TO MATCH NL } |
| 21 |
> |
snfk(i) : select(i, snf(1), snf(2)); |
| 22 |
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| 23 |
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{ Note that we assume i and o vectors are normalized, both pointing away } |
| 24 |
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| 25 |
< |
sum(i,dx,dy,dz) : if(.5-i, 0, sum(i-1) + |
| 26 |
< |
rho_s(i)*snfk(i)*noneg(Cx(i)*dx + Cy(i)*dy + Cz(i)*dz)^n(i)); |
| 25 |
> |
sum(i,dx,dy,dz) : if(.5-i, 0, sum(i-1,dx,dy,dz) + |
| 26 |
> |
snfk(i)*noneg(Cx(i)*dx + Cy(i)*dy + Cz(i)*dz)^n(i)); |
| 27 |
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|
| 28 |
< |
lafortune(ix,iy,iz,ox,oy,oz) : if( -iz*oz, 0, rho_d/PI + sum(NL,ix*ox,iy*oy,iz*oz) ); |
| 28 |
> |
lafortune(ix,iy,iz,ox,oy,oz) : if( -iz*oz, 0, |
| 29 |
> |
rho_d/PI + rho_s*sum(NL,ix*ox,iy*oy,iz*oz) ); |
