211 |
|
Distributed ray-tracing performs anti-aliasing by randomly sampling |
212 |
|
over pixels. |
213 |
|
A value of one will randomly distribute samples over full |
214 |
< |
pixels. |
214 |
> |
pixels, and is not really recommended due to the tendency of |
215 |
> |
samples to (nearly) coincide. |
216 |
|
A value of zero samples pixel centers only. |
217 |
< |
A value between zero and one is usually best |
217 |
< |
for low-resolution images. |
217 |
> |
A value around 0.5-0.8 is typical. |
218 |
|
.TP |
219 |
|
.BI -pm \ frac |
220 |
|
Set the pixel motion blur to |
310 |
|
specification will be calculated. |
311 |
|
.TP |
312 |
|
.BI -dr \ N |
313 |
< |
Set the number of relays for secondary sources to |
313 |
> |
Set the number of relays for virtual sources to |
314 |
|
.I N. |
315 |
< |
A value of 0 means that secondary sources will be ignored. |
315 |
> |
A value of 0 means that virtual sources will be ignored. |
316 |
|
A value of 1 means that sources will be made into first generation |
317 |
< |
secondary sources; a value of 2 means that first generation |
318 |
< |
secondary sources will also be made into second generation secondary |
317 |
> |
virtual sources; a value of 2 means that first generation |
318 |
> |
virtual sources will also be made into second generation virtual |
319 |
|
sources, and so on. |
320 |
|
.TP |
321 |
|
.BI -dp \ D |
322 |
< |
Set the secondary source presampling density to D. |
322 |
> |
Set the virtual source presampling density to D. |
323 |
|
This is the number of samples per steradian |
324 |
|
that will be used to determine ahead of time whether or not |
325 |
|
it is worth following shadow rays through all the reflections and/or |
326 |
< |
transmissions associated with a secondary source path. |
327 |
< |
A value of 0 means that the full secondary source path will always |
326 |
> |
transmissions associated with a virtual source path. |
327 |
> |
A value of 0 means that the full virtual source path will always |
328 |
|
be tested for shadows if it is tested at all. |
329 |
|
.TP |
330 |
|
.BR \-dv |
439 |
|
Set the ambient accuracy to |
440 |
|
.I acc. |
441 |
|
This value will approximately equal the error |
442 |
< |
from indirect illuminance interpolation. |
442 |
> |
from indirect irradiance interpolation. |
443 |
|
A value of zero implies no interpolation. |
444 |
|
.TP |
445 |
|
.BI -ad \ N |
446 |
|
Set the number of ambient divisions to |
447 |
|
.I N. |
448 |
|
The error in the Monte Carlo calculation of indirect |
449 |
< |
illuminance will be inversely proportional to the square |
449 |
> |
irradiance will be inversely proportional to the square |
450 |
|
root of this number. |
451 |
|
A value of zero implies no indirect calculation. |
452 |
|
.TP |
459 |
|
.BI -af \ fname |
460 |
|
Set the ambient file to |
461 |
|
.I fname. |
462 |
< |
This is where indirect illuminance will be stored and retrieved. |
463 |
< |
Normally, indirect illuminance values are kept in memory and |
462 |
> |
This is where indirect irradiance will be stored and retrieved. |
463 |
> |
Normally, indirect irradiance values are kept in memory and |
464 |
|
lost when the program finishes or dies. |
465 |
< |
By using a file, different invocations can share illuminance |
465 |
> |
By using a file, different invocations can share irradiance |
466 |
|
values, saving time in the computation. |
467 |
< |
Also, by creating an ambient file during a low resolution rendering, |
468 |
< |
better results can be obtained in a second high resolution pass. |
467 |
> |
Also, by creating an ambient file during a low-resolution rendering, |
468 |
> |
better results can be obtained in a second high-resolution pass. |
469 |
> |
(It is a good idea to keep all of the calculation parameters the same, |
470 |
> |
changing only the dimensions of the output picture.)\0 |
471 |
|
The ambient file is in a machine-independent binary format |
472 |
|
which may be examined with |
473 |
|
.I lookamb(1). |
597 |
|
.I \-ac. |
598 |
|
Note that this is approximate as the number of cache pages is rounded to |
599 |
|
the nearest prime. This allows adapting the cache to the available physical |
600 |
< |
memory. In conjunction with the |
601 |
< |
.I \-n |
602 |
< |
option, this is the cache size |
603 |
< |
.I per parallel process. |
602 |
< |
Cache performance is less sensitive to this parameter, |
603 |
< |
and reasonable performance can obtained with as few as 10k photons. The |
604 |
< |
default is 1M. This option recognises multiplier suffixes (k = 1e3, M = |
605 |
< |
1e6), both in upper and lower case. |
600 |
> |
memory. Cache performance is less sensitive to this parameter, and reasonable |
601 |
> |
performance can obtained with as few as 10k photons. The default is 1M. This |
602 |
> |
option recognises multiplier suffixes (k = 1e3, M = 1e6), both in upper and |
603 |
> |
lower case. |
604 |
|
.TP |
605 |
|
.BI -me " rext gext bext" |
606 |
|
Set the global medium extinction coefficient to the indicated color, |
664 |
|
termination, and the |
665 |
|
.I -lw |
666 |
|
setting (below) must be positive. |
667 |
< |
If N is a negative integer, then this sets the upper limit |
668 |
< |
of reflections past which Russian roulette will be used. |
667 |
> |
If N is a negative integer, then this limits the maximum |
668 |
> |
number of reflections even with Russian roulette. |
669 |
|
In scenes with dielectrics and total internal reflection, |
670 |
|
a setting of 0 (no limit) may cause a stack overflow. |
671 |
|
.TP |
886 |
|
.PP |
887 |
|
rpict \-S 1 \-o frame%02d.hdr scene.oct < keyframes.vf |
888 |
|
.PP |
889 |
< |
To render ambient illuminance in photon mapping mode from a global photon |
889 |
> |
To render ambient irradiance in photon mapping mode from a global photon |
890 |
|
map global.pm via one ambient bounce, and from a caustic photon map |
891 |
|
caustic.pm: |
892 |
|
.IP "" .2i |
912 |
|
Greg Ward |
913 |
|
.SH "SEE ALSO" |
914 |
|
getinfo(1), lookamb(1), mkpmap(1), oconv(1), pdfblur(1), pfilt(1), |
915 |
< |
pinterp(1), pmblur(1), printf(3), ra_rgbe(1), rad(1), rtrace(1), rvu(1) |
915 |
> |
pinterp(1), pmblur(1), printf(3), ra_rgbe(1), rad(1), rpiece(1), rtpict(1), rtrace(1), rvu(1) |