| 8 |
|
.B "\-n spp" |
| 9 |
|
][ |
| 10 |
|
.B "\-h|\-q" |
| 11 |
+ |
][ |
| 12 |
+ |
.B "\-pC" |
| 13 |
+ |
][ |
| 14 |
+ |
.B "\-l maxlobes" |
| 15 |
|
] |
| 16 |
|
[ |
| 17 |
|
.B "bsdf.sir .." |
| 24 |
|
.B "\-n spp" |
| 25 |
|
][ |
| 26 |
|
.B "\-h|\-q" |
| 27 |
+ |
][ |
| 28 |
+ |
.B "\-pC" |
| 29 |
|
] |
| 30 |
|
.B bsdf_in.xml |
| 31 |
|
.br |
| 37 |
|
][ |
| 38 |
|
.B "\-h|\-q" |
| 39 |
|
][ |
| 40 |
+ |
.B "\-pC" |
| 41 |
+ |
][ |
| 42 |
|
.B "{+|-}forward" |
| 43 |
|
][ |
| 44 |
|
.B "{+|-}backward" |
| 45 |
|
][ |
| 46 |
< |
.B "\-e expr |
| 46 |
> |
.B "\-e expr" |
| 47 |
|
][ |
| 48 |
< |
.B "\-f file |
| 48 |
> |
.B "\-f file" |
| 49 |
|
] |
| 50 |
|
.B bsdf_func |
| 51 |
|
.SH DESCRIPTION |
| 69 |
|
Neither option is recommended unless the distribution is known to |
| 70 |
|
be approximately diffuse. |
| 71 |
|
.PP |
| 72 |
+ |
The |
| 73 |
+ |
.I \-p |
| 74 |
+ |
option by itself turns off the progress bar, whose length may be set |
| 75 |
+ |
by an immediately following integer argument. |
| 76 |
+ |
(The default progress bar length is 79 characters.)\0 |
| 77 |
+ |
.PP |
| 78 |
+ |
The |
| 79 |
+ |
.I \-l |
| 80 |
+ |
option may be used to specify the maximum number of lobes in any |
| 81 |
+ |
interpolated radial basis function. |
| 82 |
+ |
The default value is 15000, which generally keeps the interpolation tractable. |
| 83 |
+ |
Setting the value to 0 turns off this limit. |
| 84 |
+ |
.PP |
| 85 |
|
Normally, multiple samples are taken from random points on each input |
| 86 |
|
and output patch to improve accuracy. |
| 87 |
|
The number of samples to take for each input-output patch pair may |
| 88 |
|
be controlled using the |
| 89 |
|
.I \-n |
| 90 |
< |
option, which defaults to 256. |
| 90 |
> |
option, which defaults to 1024. |
| 91 |
|
.PP |
| 92 |
|
The first invocation form takes a intermediate scattering representation |
| 93 |
|
as produced by |
| 111 |
|
In the third invocation form, |
| 112 |
|
.I bsdf2klems |
| 113 |
|
takes a functional specification of a BSDF. |
| 114 |
< |
The named function must accept 6 parameters corresponding to the |
| 114 |
> |
The named function should accept 6 parameters corresponding to the |
| 115 |
|
normalized incident and exiting vectors, respectively. |
| 116 |
|
By convention, these vectors point away from the surface, and a positive |
| 117 |
|
Z-component corresponds to the front side. |
| 118 |
|
The Y-component corresponds to the "up" orientation of the surface, |
| 119 |
|
as specified in the eventual scene description that references the XML |
| 120 |
|
output. |
| 121 |
+ |
If the function only takes 3 parameters, then the variables "Dx", "Dy", |
| 122 |
+ |
and "Dz" will be assigned to the reverse of the outgoing direction at |
| 123 |
+ |
each evaluation. |
| 124 |
+ |
(I.e., the vector will point into the surface and |
| 125 |
+ |
Dz will be negative on the front side.)\0 |
| 126 |
+ |
This simplifies conversion of functional BSDF specifications using the |
| 127 |
+ |
legacy material primitives "plasfunc", "metfunc", and "transfunc". |
| 128 |
|
.PP |
| 129 |
|
The function is defined by one or more |
| 130 |
|
.I \-e |
| 133 |
|
options, and should obey both Helmholtz reciprocity and |
| 134 |
|
integrate to less than 1 over each projected incident hemisphere |
| 135 |
|
for energy conservation. |
| 136 |
+ |
The variable and function definitions in each |
| 137 |
+ |
.I \-f source |
| 138 |
+ |
file are read and compiled from the RADIANCE library where it is found. |
| 139 |
|
.PP |
| 140 |
|
Similar to the |
| 141 |
|
.I genBSDF(1) |
| 166 |
|
isotropic Phong distribution: |
| 167 |
|
.IP "" .2i |
| 168 |
|
bsdf2klems -e 'phong(ix,iy,iz,ox,oy,oz) = if(iz, .1+((iz+oz)/sqrt((ix+ox)^2+(iy+oy)^2+(iz+oz)^2))^50, 0)' phong > phong.xml |
| 169 |
+ |
.SH ENVIRONMENT |
| 170 |
+ |
RAYPATH the directories to check for auxiliary files. |
| 171 |
|
.SH AUTHOR |
| 172 |
|
Greg Ward |
| 173 |
|
.SH "SEE ALSO" |
| 174 |
|
bsdf2ttree(1), dctimestep(1), icalc(1), gendaymtx(1), genklemsamp(1), |
| 175 |
< |
genskyvec(1), mkillum(1), genBSDF(1), pkgBSDF(1), rcontrib(1), rtrace(1) |
| 175 |
> |
genskyvec(1), mkillum(1), genBSDF(1), pabopto2bsdf(1), pabopto2xyz(1), |
| 176 |
> |
pkgBSDF(1), rcontrib(1), rfluxmtx(1), rmtxop(1), wrapBSDF(1) |
