| 9 |
|
][ |
| 10 |
|
.B "\-n Nproc" |
| 11 |
|
][ |
| 12 |
+ |
.B "\-r 'rtcontrib opts...'" |
| 13 |
+ |
][ |
| 14 |
+ |
.B "{+|-}forward" |
| 15 |
+ |
][ |
| 16 |
+ |
.B "{+|-}backward" |
| 17 |
+ |
][ |
| 18 |
|
.B "{+|-}mgf" |
| 19 |
|
][ |
| 20 |
|
.B "{+|-}geom |
| 26 |
|
] |
| 27 |
|
.SH DESCRIPTION |
| 28 |
|
.I GenBSDF |
| 29 |
< |
computes a bidirectional transmittance distribution function from |
| 29 |
> |
computes a bidirectional scattering distribution function from |
| 30 |
|
a Radiance or MGF scene description given on the input. |
| 31 |
|
The program assumes the input is in Radiance format unless the |
| 32 |
|
.I \+mgf |
| 35 |
|
and will include an MGF representation of the input geometry if the |
| 36 |
|
.I \+geom |
| 37 |
|
option is given. |
| 38 |
< |
(This is currently the default, and may be switche off using |
| 38 |
> |
(This is the default, and may be switched off using |
| 39 |
|
.I \-geom.)\0 |
| 40 |
|
.PP |
| 41 |
+ |
Normally, |
| 42 |
+ |
.I genBSDF |
| 43 |
+ |
computes components needed by a backwards ray-tracing process, |
| 44 |
+ |
.I \+backward. |
| 45 |
+ |
If both forward and backward (front and back) distributions are needed, the |
| 46 |
+ |
.I \+forward |
| 47 |
+ |
option may be given. |
| 48 |
+ |
To turn off backward components, use the |
| 49 |
+ |
.I \-backward |
| 50 |
+ |
option. |
| 51 |
+ |
Computing both components takes about twice as long as one component. |
| 52 |
+ |
.PP |
| 53 |
|
The geometry must fit a rectangular profile, whose width is along the X-axis, |
| 54 |
|
height is in the Y-axis, and depth is in the Z-axis. |
| 55 |
|
The positive Z-axis points into the room, and the input geometry should |
| 81 |
|
.I rtrace(1) |
| 82 |
|
processes to run in |
| 83 |
|
.I rtcontrib(1). |
| 84 |
+ |
The |
| 85 |
+ |
.I \-r |
| 86 |
+ |
option may be used to specify a set of quoted arguments to be |
| 87 |
+ |
included on the |
| 88 |
+ |
.I rtcontrib |
| 89 |
+ |
command line. |
| 90 |
|
.SH EXAMPLE |
| 91 |
|
To create a BSDF description including geometry from a set of venetian blinds: |
| 92 |
|
.IP "" .2i |
| 93 |
|
genblinds blind_white blind1 .07 3 1.5 30 40 | xform -rz -90 -rx 90 > blind1.rad |
| 94 |
|
.br |
| 95 |
< |
genBSDF blind_white.mat glazing.rad blind1.rad > blind1.xml |
| 72 |
< |
.SH NOTES |
| 73 |
< |
Currently, |
| 74 |
< |
.I genBSDF |
| 75 |
< |
computes only the forward visible transmitted component, |
| 76 |
< |
though the XML specification provides for front and back |
| 77 |
< |
transmission and reflection as well. |
| 95 |
> |
genBSDF -r @rtc.opt blind_white.mat glazing.rad blind1.rad > blind1.xml |
| 96 |
|
.SH AUTHOR |
| 97 |
|
Greg Ward |
| 98 |
|
.SH "SEE ALSO" |
