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.SH SYNOPSIS |
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.B bsdf2ttree |
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[ |
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.B "\-pC" |
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][ |
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.B "{+|-}a" |
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][ |
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.B "\-g Nlog2" |
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][ |
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.B "\-t pctcull" |
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][ |
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.B "\-n nss" |
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][ |
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.B "\-s thresh" |
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][ |
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.B "\-l maxlobes" |
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] |
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[ |
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.B bsdf2ttree |
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.B "\-t{3|4}" |
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[ |
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.B "\-pC" |
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][ |
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.B "{+|-}a" |
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][ |
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.B "\-g Nlog2" |
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][ |
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.B "\-t pctcull" |
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][ |
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.B "\-n nss" |
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][ |
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.B "\-s thresh" |
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][ |
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.B "{+|-}forward" |
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][ |
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.B "{+|-}backward" |
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A complete XML description is written to the standard output, |
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which is normally redirected to a file. |
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.PP |
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The |
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.I \-p |
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option by itself turns off the progress bar, whose length may be set |
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by an immediately following integer argument. |
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(The default progress bar length is 79 characters.)\0 |
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.PP |
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The |
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.I \-a |
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option turns off reciprocity averaging for isotropic scattering or anisotropic reflection. |
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Normally on (+a), this ensures that the tensor BRDF obeys Helmholtz reciprocity. |
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However, in certain rare cases, reciprocity averaging can cause unwanted noise in the output. |
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.PP |
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The maximum resolution of the tensor tree may be controlled by the |
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.I \-g |
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option, which defaults to a value of 6. |
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Setting this parameter to -1 turns culling off entirely, which may be |
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useful for comparisons. |
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.PP |
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The |
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.I \-n |
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option controls the number of super-samples to send in patches whose |
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difference to its neighbors exceeds some threshold. |
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The default number of super-samples is 256. |
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The difference threshold for super-sampling is controlled by the |
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.I \-s |
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option, and defaults to 0.35. |
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.PP |
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The first invocation form takes a intermediate scattering representation |
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as produced by |
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.I pabopto2bsdf(1) |
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options, and should obey both Helmholtz reciprocity and |
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integrate to less than 1 over each projected incident hemisphere |
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for energy conservation. |
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The variable and function definitions in each |
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.I \-f source |
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file are read and compiled from the RADIANCE library where it is found. |
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If the |
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.I \-t3 |
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option is specified, the defined function is assumed to be isotropic. |
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isotropic Phong distribution: |
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.IP "" .2i |
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bsdf2ttree -g 5 -t3 -e 'phong(ix,iy,iz,ox,oy,oz) = if(iz, .1+((iz+oz)/sqrt((ix+ox)^2+(iy+oy)^2+(iz+oz)^2))^50, 0)' phong > phong.xml |
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.SH ENVIRONMENT |
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RAYPATH the directories to check for auxiliary files. |
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.SH AUTHOR |
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Greg Ward |
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.SH "SEE ALSO" |
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< |
bsdf2klems(1), icalc(1), genBSDF(1), pkgBSDF(1) |
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> |
bsdf2klems(1), icalc(1), genBSDF(1), pkgBSDF(1), rcontrib(1), |
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> |
rfluxmtx(1), wrapBSDF(1) |
