| 9 |
|
][ |
| 10 |
|
.B \-V |
| 11 |
|
][ |
| 12 |
+ |
.B "\-t secs" |
| 13 |
+ |
][ |
| 14 |
|
.B "\-c count" |
| 15 |
|
][ |
| 16 |
|
.B \-fo |
| 45 |
|
.B octree |
| 46 |
|
.br |
| 47 |
|
.B "rcontrib [ options ] \-defaults" |
| 48 |
+ |
.br |
| 49 |
+ |
.B "rcontrib \-features [feat1 ..]" |
| 50 |
|
.SH DESCRIPTION |
| 51 |
|
.I Rcontrib |
| 52 |
|
computes ray coefficients |
| 123 |
|
.I \-c |
| 124 |
|
set to zero. |
| 125 |
|
.PP |
| 126 |
+ |
Output flushing at fixed intervals may be enabled with the |
| 127 |
+ |
.I \-x |
| 128 |
+ |
option, which specifies the number of records |
| 129 |
+ |
(-c accumulations) before each flush. |
| 130 |
+ |
If the |
| 131 |
+ |
.I \-y |
| 132 |
+ |
option is also set, then periodic flushing is disabled and the |
| 133 |
+ |
output size for an RGB image is the taken from the x and y dimensions. |
| 134 |
+ |
In lieu of periodic flushing, a flush may be forced as mentioned above |
| 135 |
+ |
by sending a sample with a zero direction vector, although you |
| 136 |
+ |
must still send a full record of rays before output occurs. |
| 137 |
+ |
.PP |
| 138 |
+ |
If progress reports are desired, the |
| 139 |
+ |
.I \-t |
| 140 |
+ |
option specifies a time interval in seconds for reports sent to |
| 141 |
+ |
standard error. |
| 142 |
+ |
This requires that the number of input samples is known, meaning a |
| 143 |
+ |
.I \-y |
| 144 |
+ |
parameter has been specified. |
| 145 |
+ |
.PP |
| 146 |
|
The output of |
| 147 |
|
.I rcontrib |
| 148 |
|
has many potential uses. |
| 182 |
|
option may be used to further define |
| 183 |
|
a "bin number" within each object if finer resolution is needed, and |
| 184 |
|
this will be applied to a "%d" format in the output file |
| 185 |
< |
specification if present. |
| 185 |
> |
specification if present. |
| 186 |
> |
(The final integer will be offset incrementally |
| 187 |
> |
if the output is a RADIANCE picture and more than one modifier has |
| 188 |
> |
the same format specification.)\0 |
| 189 |
|
The actual bin number is computed at run time based on ray direction |
| 190 |
|
and surface intersection, as described below. |
| 191 |
|
The number of bins must be specified in advance with the |
| 208 |
|
.I \-o |
| 209 |
|
options to the left of each |
| 210 |
|
.I \-m |
| 211 |
< |
setting are the ones used for that modifier. |
| 211 |
> |
name are the ones used for that modifier. |
| 212 |
> |
Any |
| 213 |
> |
.I \-cs |
| 214 |
> |
option changing the number of spectral color |
| 215 |
> |
samples must appear before the first modifier. |
| 216 |
|
The ordering of other options is unimportant, except for |
| 217 |
|
.I \-x |
| 218 |
|
and |
| 239 |
|
with a |
| 240 |
|
.I \-p |
| 241 |
|
option, which contains a list of variable names and assigned values, separated |
| 242 |
< |
by commas or semicolons. |
| 242 |
> |
by commas, colons, or semicolons. |
| 243 |
|
The computed bin value will be |
| 244 |
|
rounded to the nearest whole number. |
| 245 |
|
(Negative bin values will be silently ignored.)\0 |
| 309 |
|
replaced by the contents of the given environment variable. |
| 310 |
|
A command argument beginning with an at sign ('@') is immediately |
| 311 |
|
replaced by the contents of the given file. |
| 312 |
+ |
.PP |
| 313 |
+ |
.I Rcontrib |
| 314 |
+ |
supports light source contributions from photon maps generated by |
| 315 |
+ |
.I mkpmap(1) |
| 316 |
+ |
with its |
| 317 |
+ |
.I -apC |
| 318 |
+ |
option. Enabling photon mapping is described in the |
| 319 |
+ |
.I rtrace |
| 320 |
+ |
man page along with its relevant settings. In photon mapping mode, |
| 321 |
+ |
.I rcontrib |
| 322 |
+ |
only supports contributions from light sources, not arbitrary modifiers. |
| 323 |
+ |
The |
| 324 |
+ |
.I -b |
| 325 |
+ |
option is supported along with its associated ray variables, as |
| 326 |
+ |
discussed above. Ray coefficients are also supported via the |
| 327 |
+ |
.I \-V- |
| 328 |
+ |
option. Using fewer photons than there are light sources for the photon |
| 329 |
+ |
density estimates results in omitted contributions, thus the bandwidth |
| 330 |
+ |
is clamped accordingly and a warning is issued. |
| 331 |
|
.SH EXAMPLES |
| 332 |
|
To compute the proportional contributions from sources modified |
| 333 |
< |
by "light1" vs. "light2" on a set of illuminance values: |
| 333 |
> |
by "light1" vs. "light2" on a set of irradiance values: |
| 334 |
|
.IP "" .2i |
| 335 |
|
rcontrib \-I+ @render.opt \-o c_%s.dat \-m light1 \-m light2 scene.oct < test.dat |
| 336 |
|
.PP |
| 346 |
|
.IP "" .2i |
| 347 |
|
pcomb \-c 100 90 75 c_light1.hdr \-c 50 55 57 c_light2.hdr > combined.hdr |
| 348 |
|
.PP |
| 349 |
< |
To compute an array of illuminance contributions according to a Tregenza sky: |
| 349 |
> |
To compute an array of irradiance contributions according to a Tregenza sky: |
| 350 |
|
.IP "" .2i |
| 351 |
|
rcontrib \-I+ \-f tregenza.cal \-b tbin \-bn Ntbins \-o sky.dat \-m skyglow |
| 352 |
|
\-b 0 \-o ground.dat \-m groundglow @render.opt scene.oct < test.dat |
| 353 |
+ |
.PP |
| 354 |
+ |
To perform an annual simulation of 365 daily sun positions in photon mapping |
| 355 |
+ |
mode: |
| 356 |
+ |
.IP "" .2i |
| 357 |
+ |
rcontrib \-I+ \-h \-V \-fo \-o c_%s.dat \-M lights \-ap contrib.pm 365 |
| 358 |
+ |
scene.oct < test.dat, |
| 359 |
|
.SH ENVIRONMENT |
| 360 |
|
RAYPATH path to search for \-f and \-M files |
| 361 |
+ |
.SH BUGS |
| 362 |
+ |
We do not currently compute contributions or coefficients properly |
| 363 |
+ |
in scenes with participating media. |
| 364 |
+ |
A single warning will be issued if a scattering or absorbing medium |
| 365 |
+ |
is detected. |
| 366 |
|
.SH AUTHOR |
| 367 |
|
Greg Ward |
| 368 |
|
.SH "SEE ALSO" |
| 369 |
< |
cnt(1), genklemsamp(1), getinfo(1), pcomb(1), pfilt(1), ra_rgbe(1), |
| 370 |
< |
rcalc(1), rpict(1), rsensor(1), rtrace(1), total(1), vwrays(1), ximage(1) |
| 369 |
> |
cnt(1), genklemsamp(1), getinfo(1), mkpmap(1), pcomb(1), pfilt(1), |
| 370 |
> |
ra_rgbe(1), rcalc(1), rcomb(1), rfluxmtx(1), rmtxop(1), rpict(1), |
| 371 |
> |
rsensor(1), rtrace(1), total(1), vwrays(1), ximage(1) |
| 372 |
> |
|
