| 4 |
|
|
| 5 |
|
Assumes material in X-Y plane with Y axis "up" and surface normal is Z-axis |
| 6 |
|
} |
| 7 |
– |
Up(i) = arg(AC-3+i); { up vector does not need to be normalized } |
| 8 |
– |
Vux = cross(1,Up,N); |
| 9 |
– |
Vuy = cross(2,Up,N); |
| 10 |
– |
Vuz = cross(3,Up,N); |
| 11 |
– |
vnorm = 1/sqrt(Vux*Vux + Vuy*Vuy + Vuz*Vuz); |
| 12 |
– |
Vnx = Vux*vnorm; |
| 13 |
– |
Vny = Vuy*vnorm; |
| 14 |
– |
Vnz = Vuz*vnorm; |
| 15 |
– |
Vn(i) = select(i, Vnx, Vny, Vnz); |
| 16 |
– |
Unx = cross(1,N,Vn); |
| 17 |
– |
Uny = cross(2,N,Vn); |
| 18 |
– |
Unz = cross(3,N,Vn); |
| 19 |
– |
{ Transform vectors, normalized (dx,dy,dz) away from surf } |
| 20 |
– |
surf_dx(dx,dy,dz) = dx*Unx + dy*Uny + dz*Unz; |
| 21 |
– |
surf_dy(dx,dy,dz) = dx*Vnx + dy*Vny + dz*Vnz; |
| 22 |
– |
surf_dz(dx,dy,dz) = dx*Nx + dy*Ny + dz*Nz; |
| 23 |
– |
|
| 24 |
– |
inc_dx = surf_dx(-Dx,-Dy,-Dz); |
| 25 |
– |
inc_dy = surf_dy(-Dx,-Dy,-Dz); |
| 26 |
– |
inc_dz = Rdot; |
| 7 |
|
{ Compute square position from disk coordinates } |
| 8 |
|
norm_radians(p) : if(-p - PI/4, p + 2*PI, p); |
| 9 |
|
idr(idx,idy) = sqrt(idx*idx + idy*idy); |
| 26 |
|
square_x(idx,idy) = (square_a(idr(idx,idy),idp(idx,idy)) + 1)/2; |
| 27 |
|
square_y(idx,idy) = (square_b(idr(idx,idy),idp(idx,idy)) + 1)/2; |
| 28 |
|
|
| 29 |
< |
inc_sqx = square_x(-inc_dx,-inc_dy); { Negative because of Klems reversal } |
| 30 |
< |
inc_sqy = square_y(-inc_dx,-inc_dy); |
| 29 |
> |
inc_sqx = square_x(-Idx,-Idy); { Negative because of Klems reversal } |
| 30 |
> |
inc_sqy = square_y(-Idx,-Idy); |
| 31 |
|
|
| 32 |
|
sqx_in(sx,sy,sz) = inc_sqx; { Only a function of incident ray direction } |
| 33 |
|
sqy_in(sx,sy,sz) = inc_sqy; |
| 34 |
|
|
| 35 |
< |
sqx_out(sx,sy,sz) = square_x(surf_dx(sx,sy,sz),surf_dy(sx,sy,sz)); |
| 36 |
< |
sqy_out(sx,sy,sz) = square_y(surf_dx(sx,sy,sz),surf_dy(sx,sy,sz)); |
| 35 |
> |
sqx_out(sx,sy,sz) = square_x(Ldx(sx,sy,sz),Ldy(sx,sy,sz)); |
| 36 |
> |
sqy_out(sx,sy,sz) = square_y(Ldx(sx,sy,sz),Ldy(sx,sy,sz)); |
