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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 |
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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. |
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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. |
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A value between zero and one is usually best |
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for low-resolution images. |
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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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.I \-pd |
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option, to avoid the ghosting effect of too few samples. |
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.TP |
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.BI -pc " xr yr xg yg xb yb xw yw" |
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Use the specified chromaticity pairs for output primaries and white |
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point rather than the standard RGB color space. |
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.TP |
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.BR \-pRGB |
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Output standard RGB values (the default). |
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.TP |
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.BR \-pXYZ |
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Output standard CIE XYZ tristimulus values rather than RGB. |
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.TP |
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.BI -dj \ frac |
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Set the direct jittering to |
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.I frac. |
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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 |
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Set the number of relays for virtual sources to |
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.I N. |
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A value of 0 means that secondary sources will be ignored. |
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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 |
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secondary sources; a value of 2 means that first generation |
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secondary sources will also be made into second generation secondary |
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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. |
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Set the virtual source presampling density to D. |
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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. |
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A value of 0 means that the full secondary source path will always |
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transmissions associated with a virtual source path. |
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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. |
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.TP |
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.BR \-dv |
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Set the ambient accuracy to |
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.I acc. |
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This value will approximately equal the error |
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from indirect illuminance interpolation. |
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from indirect irradiance interpolation. |
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A value of zero implies no interpolation. |
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|
.TP |
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|
.BI -ad \ N |
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Set the number of ambient divisions to |
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.I N. |
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The error in the Monte Carlo calculation of indirect |
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illuminance will be inversely proportional to the square |
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> |
irradiance will be inversely proportional to the square |
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root of this number. |
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A value of zero implies no indirect calculation. |
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.TP |
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.BI -af \ fname |
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Set the ambient file to |
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.I fname. |
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This is where indirect illuminance will be stored and retrieved. |
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Normally, indirect illuminance values are kept in memory and |
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This is where indirect irradiance will be stored and retrieved. |
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Normally, indirect irradiance values are kept in memory and |
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lost when the program finishes or dies. |
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By using a file, different invocations can share illuminance |
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> |
By using a file, different invocations can share irradiance |
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values, saving time in the computation. |
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Also, by creating an ambient file during a low resolution rendering, |
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better results can be obtained in a second high resolution pass. |
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Also, by creating an ambient file during a low-resolution rendering, |
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better results can be obtained in a second high-resolution pass. |
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(It is a good idea to keep all of the calculation parameters the same, |
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changing only the dimensions of the output picture.)\0 |
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The ambient file is in a machine-independent binary format |
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which may be examined with |
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.I lookamb(1). |
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divided by the given |
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|
.I frac. |
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|
.TP |
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+ |
.BI -cs \ Ns |
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Use |
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.I Ns |
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bands for spectral sampling rather than the default RGB calculation space. |
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The maximum setting is controlled by the compiler macro MAXCSAMP, and |
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defaults to 24. |
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Larger values for Ns will be reduced to MAXCSAMP. |
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.TP |
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.BI -cw " nmA nmB" |
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Set extrema to the given wavelengths for spectral sampling. |
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The default is 380 and 780 nanometers. |
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The order specified does not matter. |
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.TP |
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.BI -S \ seqstart |
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Instead of generating a single picture based only on the view |
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parameters given on the command line, this option causes |
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|
.PP |
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rpict \-S 1 \-o frame%02d.hdr scene.oct < keyframes.vf |
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.PP |
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< |
To render ambient illuminance in photon mapping mode from a global photon |
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> |
To render ambient irradiance in photon mapping mode from a global photon |
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map global.pm via one ambient bounce, and from a caustic photon map |
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caustic.pm: |
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.IP "" .2i |
