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] |
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|
.br |
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.B "rpict [ options ] \-defaults" |
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+ |
.br |
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+ |
.B "rpict \-features [feat1 ..]" |
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.SH DESCRIPTION |
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.I Rpict |
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generates a picture from the RADIANCE scene given in |
| 43 |
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for the options (modified by those options present) |
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are printed with a brief explanation. |
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.PP |
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+ |
In the third form, a list of supported features is sent |
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+ |
to the standard output, one per line. |
| 48 |
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If additional arguments follow, they are checked for presence in |
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this list. |
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If a feature includes subfeatures, these may be checked as well by |
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specifying: |
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+ |
.nf |
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+ |
|
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+ |
rpict -features FeatName=subfeat1,subfeat2 |
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+ |
|
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+ |
.fi |
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+ |
If any named feature or subfeature is missing, an error is |
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+ |
reported and the program returns an error status. |
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+ |
If all of the named features are present, a zero status is returned. |
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+ |
.PP |
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Most options are followed by one or more arguments, which must be |
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separated from the option and each other by white space. |
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The exceptions to this rule are the |
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Distributed ray-tracing performs anti-aliasing by randomly sampling |
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over pixels. |
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A value of one will randomly distribute samples over full |
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< |
pixels. |
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> |
pixels, and is not really recommended due to the tendency of |
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> |
samples to (nearly) coincide. |
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A value of zero samples pixel centers only. |
| 234 |
< |
A value between zero and one is usually best |
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< |
for low-resolution images. |
| 234 |
> |
A value around 0.5-0.8 is typical. |
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|
.TP |
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|
.BI -pm \ frac |
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Set the pixel motion blur to |
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|
specification will be calculated. |
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|
.TP |
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|
.BI -dr \ N |
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< |
Set the number of relays for secondary sources to |
| 330 |
> |
Set the number of relays for virtual sources to |
| 331 |
|
.I N. |
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< |
A value of 0 means that secondary sources will be ignored. |
| 332 |
> |
A value of 0 means that virtual sources will be ignored. |
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|
A value of 1 means that sources will be made into first generation |
| 334 |
< |
secondary sources; a value of 2 means that first generation |
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< |
secondary sources will also be made into second generation secondary |
| 334 |
> |
virtual sources; a value of 2 means that first generation |
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> |
virtual sources will also be made into second generation virtual |
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|
sources, and so on. |
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|
.TP |
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|
.BI -dp \ D |
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< |
Set the secondary source presampling density to D. |
| 339 |
> |
Set the virtual source presampling density to D. |
| 340 |
|
This is the number of samples per steradian |
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|
that will be used to determine ahead of time whether or not |
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|
it is worth following shadow rays through all the reflections and/or |
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< |
transmissions associated with a secondary source path. |
| 344 |
< |
A value of 0 means that the full secondary source path will always |
| 343 |
> |
transmissions associated with a virtual source path. |
| 344 |
> |
A value of 0 means that the full virtual source path will always |
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|
be tested for shadows if it is tested at all. |
| 346 |
|
.TP |
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|
.BR \-dv |
| 456 |
|
Set the ambient accuracy to |
| 457 |
|
.I acc. |
| 458 |
|
This value will approximately equal the error |
| 459 |
< |
from indirect illuminance interpolation. |
| 459 |
> |
from indirect irradiance interpolation. |
| 460 |
|
A value of zero implies no interpolation. |
| 461 |
|
.TP |
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|
.BI -ad \ N |
| 463 |
|
Set the number of ambient divisions to |
| 464 |
|
.I N. |
| 465 |
|
The error in the Monte Carlo calculation of indirect |
| 466 |
< |
illuminance will be inversely proportional to the square |
| 466 |
> |
irradiance will be inversely proportional to the square |
| 467 |
|
root of this number. |
| 468 |
|
A value of zero implies no indirect calculation. |
| 469 |
|
.TP |
| 476 |
|
.BI -af \ fname |
| 477 |
|
Set the ambient file to |
| 478 |
|
.I fname. |
| 479 |
< |
This is where indirect illuminance will be stored and retrieved. |
| 480 |
< |
Normally, indirect illuminance values are kept in memory and |
| 479 |
> |
This is where indirect irradiance will be stored and retrieved. |
| 480 |
> |
Normally, indirect irradiance values are kept in memory and |
| 481 |
|
lost when the program finishes or dies. |
| 482 |
< |
By using a file, different invocations can share illuminance |
| 482 |
> |
By using a file, different invocations can share irradiance |
| 483 |
|
values, saving time in the computation. |
| 484 |
< |
Also, by creating an ambient file during a low resolution rendering, |
| 485 |
< |
better results can be obtained in a second high resolution pass. |
| 484 |
> |
Also, by creating an ambient file during a low-resolution rendering, |
| 485 |
> |
better results can be obtained in a second high-resolution pass. |
| 486 |
> |
(It is a good idea to keep all of the calculation parameters the same, |
| 487 |
> |
changing only the dimensions of the output picture.)\0 |
| 488 |
|
The ambient file is in a machine-independent binary format |
| 489 |
|
which may be examined with |
| 490 |
|
.I lookamb(1). |
| 903 |
|
.PP |
| 904 |
|
rpict \-S 1 \-o frame%02d.hdr scene.oct < keyframes.vf |
| 905 |
|
.PP |
| 906 |
< |
To render ambient illuminance in photon mapping mode from a global photon |
| 906 |
> |
To render ambient irradiance in photon mapping mode from a global photon |
| 907 |
|
map global.pm via one ambient bounce, and from a caustic photon map |
| 908 |
|
caustic.pm: |
| 909 |
|
.IP "" .2i |
