| 9 |
|
][ |
| 10 |
|
.B "\-n Nproc" |
| 11 |
|
][ |
| 12 |
< |
.B "\-r 'rtcontrib opts...'" |
| 12 |
> |
.B "\-r 'rcontrib opts...'" |
| 13 |
|
][ |
| 14 |
+ |
.B "\-W" |
| 15 |
+ |
][ |
| 16 |
+ |
.B "\-s 'x=string;y=string'" |
| 17 |
+ |
][ |
| 18 |
|
.B "\-t{3|4} Nlog2" |
| 19 |
|
][ |
| 20 |
+ |
.B "{+|-}C" |
| 21 |
+ |
][ |
| 22 |
|
.B "{+|-}forward" |
| 23 |
|
][ |
| 24 |
|
.B "{+|-}backward" |
| 25 |
|
][ |
| 26 |
|
.B "{+|-}mgf" |
| 27 |
|
][ |
| 28 |
< |
.B "{+|-}geom |
| 28 |
> |
.B "{+|-}geom unit" |
| 29 |
|
][ |
| 30 |
|
.B "\-dim Xmin Xmax Ymin Ymax Zmin Zmax" |
| 31 |
|
] |
| 32 |
|
[ |
| 33 |
|
.B "geom .." |
| 34 |
|
] |
| 35 |
+ |
.br |
| 36 |
+ |
or |
| 37 |
+ |
.br |
| 38 |
+ |
.B genBSDF |
| 39 |
+ |
.B "\-recover tempdir" |
| 40 |
|
.SH DESCRIPTION |
| 41 |
|
.I GenBSDF |
| 42 |
|
computes a bidirectional scattering distribution function from |
| 47 |
|
The output conforms to the LBNL Window 6 XML standard for BSDF data, |
| 48 |
|
and will include an MGF representation of the input geometry if the |
| 49 |
|
.I \+geom |
| 50 |
< |
option is given. |
| 51 |
< |
(This is the default, and may be switched off using |
| 52 |
< |
.I \-geom.)\0 |
| 50 |
> |
option is given, followed by one of "meter," "foot," "inch," |
| 51 |
> |
"centimeter," or "millimeter," depending on the scene units. |
| 52 |
> |
The default is to include the provided geometry, |
| 53 |
> |
which is assumed to be in meters. |
| 54 |
> |
Geometry output can be supressed with the |
| 55 |
> |
.I \-geom |
| 56 |
> |
option, which must also be followed by one of the above length units. |
| 57 |
|
.PP |
| 58 |
|
Normally, |
| 59 |
|
.I genBSDF |
| 65 |
|
To turn off backward components, use the |
| 66 |
|
.I \-backward |
| 67 |
|
option. |
| 68 |
< |
Computing both components takes about twice as long as one component. |
| 68 |
> |
Computing both components takes about twice as long as one component, but |
| 69 |
> |
is recommended when rays will be impinging from either side. |
| 70 |
|
.PP |
| 71 |
+ |
The |
| 72 |
+ |
.I \+C |
| 73 |
+ |
option specifies that the output XML should include color information, |
| 74 |
+ |
which is interpreted by the rendering programs. |
| 75 |
+ |
The default option |
| 76 |
+ |
.I \-C |
| 77 |
+ |
reduces all BSDF data to grayscale. |
| 78 |
+ |
.PP |
| 79 |
|
The geometry must fit a rectangular profile, whose width is along the X-axis, |
| 80 |
|
height is in the Y-axis, and depth is in the Z-axis. |
| 81 |
|
The positive Z-axis points into the room, and the input geometry should |
| 98 |
|
samples per incident direction using the |
| 99 |
|
.I \-c |
| 100 |
|
option. |
| 101 |
< |
This value defaults to 1000 samples distributed over the incoming plane |
| 101 |
> |
This value defaults to 2000 samples distributed over the incoming plane |
| 102 |
|
for each of the 145 Klems hemisphere directions. |
| 103 |
|
.PP |
| 104 |
< |
In some cases, the processing time may be reduced by the |
| 104 |
> |
On multi-core machines, processing time may be reduced by the |
| 105 |
|
.I \-n |
| 106 |
|
option, which specifies the number of simultaneous |
| 83 |
– |
.I rtrace(1) |
| 107 |
|
processes to run in |
| 108 |
< |
.I rtcontrib(1). |
| 108 |
> |
.I rcontrib(1). |
| 109 |
|
The |
| 110 |
|
.I \-r |
| 111 |
|
option may be used to specify a set of quoted arguments to be |
| 112 |
|
included on the |
| 113 |
< |
.I rtcontrib |
| 113 |
> |
.I rcontrib |
| 114 |
|
command line. |
| 115 |
|
.PP |
| 116 |
|
The |
| 117 |
+ |
.I \-W |
| 118 |
+ |
option is passed to |
| 119 |
+ |
.I wrapBSDF(1) |
| 120 |
+ |
to prepare the XML file for WINDOW6. |
| 121 |
+ |
Any |
| 122 |
+ |
.I \-s |
| 123 |
+ |
parameters are passed to the |
| 124 |
+ |
.I \-f |
| 125 |
+ |
option of |
| 126 |
+ |
.I wrapBSDF, |
| 127 |
+ |
controlling XML fields such as |
| 128 |
+ |
the Manufacturer (e.g., -s m=MF) and device Name (e.g, -s n=NM). |
| 129 |
+ |
.PP |
| 130 |
+ |
The |
| 131 |
|
.I \-t4 |
| 132 |
|
mode computes a non-uniform BSDF represented as a rank 4 tensor tree, |
| 133 |
|
suitable for use in the Radiance rendering tools. |
| 141 |
|
.I \-t4 |
| 142 |
|
parameter of 5 corresponds to 32x32 or 1024 output regions, so a |
| 143 |
|
.I \-c |
| 144 |
< |
setting of 102400 would provide 100 samples per region on average. |
| 144 |
> |
setting of 10240 would provide 10 samples per region on average. |
| 145 |
|
Increasing the resolution to 6 corresponds to 64x64 or 4096 |
| 146 |
|
regions, so the |
| 147 |
|
.I \-c |
| 162 |
|
Again, the parameter to this option sets the maximum resolution as |
| 163 |
|
a power of 2 in each dimension, but in this case there is one less |
| 164 |
|
dimension being sampled. |
| 165 |
+ |
.PP |
| 166 |
+ |
The |
| 167 |
+ |
.I \-recover |
| 168 |
+ |
option is available for continuing calculations that were killed by |
| 169 |
+ |
the system or the user. |
| 170 |
+ |
Unfortunately, genBSDF puts its temporary files in a directory |
| 171 |
+ |
that is often cleaned up after reboot, so this may not always work. |
| 172 |
|
.SH EXAMPLE |
| 173 |
|
To create a BSDF description including geometry from a set of venetian blinds: |
| 174 |
|
.IP "" .2i |
| 191 |
|
.SH AUTHOR |
| 192 |
|
Greg Ward |
| 193 |
|
.SH "SEE ALSO" |
| 194 |
< |
dctimestep(1), genklemsamp(1), genskyvec(1), mkillum(1), rtcontrib(1), rtrace(1) |
| 194 |
> |
dctimestep(1), gendaymtx(1), genklemsamp(1), genskyvec(1), mkillum(1), |
| 195 |
> |
pkgBSDF(1), rcontrib(1), rfluxmtx(1), rmtxop(1), rtrace(1) wrapBSDF(1) |
