[ViewVC] Diff of: radiance/ray/doc/ray.1

Comparing ray/doc/ray.1 (file contents):
Revision 1.38 by greg, Mon Aug 31 21:54:55 2020 UTC vs.
Revision 1.46 by greg, Wed Dec 13 23:26:16 2023 UTC

+.\" RCSid "$Id$"
+.\" Print using the -ms macro package
-<
+.DA 8/31/2020
->
+.DA 11/13/2023
+.LP
-<
+.tl """Copyright \(co 2020 Regents, University of California
->
+.tl """Copyright \(co 2023 Regents, University of California
+.sp 2
+.TL
+The
+Also, rather than roughness, specular power is used, which has no
+physical meaning other than larger numbers are equivalent to a smoother
+surface.
-+
+Unlike other material types, total reflectance is the sum of
-+
+diffuse and specular colors, and should be adjusted accordingly.
+.DS
+mod ashik2 id
++ ux uy uz funcfile transform
+font such as hexbit4x1.fnt, calls for uniform spacing.
+Reasonable magnitudes for proportional spacing are
+between 0.1 (for tightly spaced characters) and 0.3 (for wide spacing).
-+
+.LP
-+
+.UL Spectrum
-+
+.PP
-+
+The spectrum primitive is the most basic type for introducing spectral
-+
+color to a material.
-+
+Since materials only provide RGB parameters, spectral patterns
-+
+are the only way to superimpose wavelength-dependent behavior.
-+
+.DS
-+
+mod spectrum id
-+
-+
-+
++ nmA nmB s1 s2 .. sN
-+
+.DE
-+
+The first two real arguments indicate the extrema of the
-+
+spectral range in nanometers.
-+
+Subsequent real values correspond to multipliers at each wavelength.
-+
+The nmA wavelength may be greater or less than nmB,
-+
+but they may not be equal, and their ordering matches
-+
+the order of the spectral values.
-+
+A minimum of 3 values must be given, which would act
-+
+more or less the same as a constant RGB multiplier.
-+
+As with RGB values, spectral quantities normally range between 0
-+
+and 1 at each wavelength, or average to 1.0 against a standard
-+
+sensitivity functions such as V(lambda).
-+
+The best results obtain when the spectral range and number
-+
+of samples match rendering options, though resampling will handle
-+
+any differences, zero-filling wavelenths outside the nmA to nmB
-+
+range.
-+
+A warning will be issued if the given wavelength range does not
-+
+adequately cover the visible spectrum.
-+
+.LP
-+
+.UL Specfile
-+
+.PP
-+
+The specfile primitive is equivalent to the spectrum type, but
-+
+the wavelength range and values are contained in a 1-dimensional
-+
+data file.
-+
+This may be a more convenient way to specify a spectral color,
-+
+especially one corresponding to a standard illuminant such as D65
-+
+or a library of measured spectra.
-+
+.DS
-+
+mod specfile id
-+
+datafile
-+
-+
-+
+.DE
-+
+As with the spectrum type, rendering wavelengths outside the defined
-+
+range will be zero-filled.
-+
+Unlike the spectrum type, the file may contain non-uniform samples.
-+
+.LP
-+
+.UL Specfunc
-+
+.PP
-+
+The specfunc primitive offers dynamic control over a spectral
-+
+pattern, similar to the colorfunc type.
-+
+.DS
-+
+mod specfunc id
-+
++ sfunc funcfile transform
-+
-+
++ nmA nmB A3 ..
-+
+.DE
-+
+Like the spectrum primitive, the wavelength range is specified
-+
+in the first two real arguments, and additional real values are
-+
+set in the evaluation context.
-+
+This function is fed a wavelenth sample
-+
+between nmA and nmB as its only argument,
-+
+and it returns the corresponding spectral intensity.
-+
+.LP
-+
+.UL Specdata
-+
+.PP
-+
+Specdata is like brightdata and colordata, but with more
-+
+than 3 specular samples.
-+
+.DS
-+
+mod specdata id
-+
++n+
-+
+        func datafile
-+
+        funcfile x1 x2 .. xn transform
-+
-+
+m A1 A2 .. Am
-+
+.DE
-+
+The data file must have one more dimension than the coordinate
-+
+variable count, as this final dimension corresponds to the covered
-+
+spectrum.
-+
+The starting and ending wavelengths are specified in "datafile"
-+
+as well as the number of spectral samples.
-+
+The function "func" will be called with two parameters, the
-+
+interpolated spectral value for the current coordinate and the
-+
+associated wavelength.
-+
+If the spectrum is broken into 12 components, then 12 calls
-+
+will be made to "func" for the relevant ray evaluation.
-+
+.LP
-+
+.UL Specpict
-+
+.PP
-+
+Specpict is a special case of specdata, where the pattern is
-+
+a hyperspectral image stored in the common-exponent file format.
-+
+The dimensions of the image data are determined by the picture
-+
+just as with the colorpict primitive.
-+
+.DS
-+
+mod specpict id
 +
-+
+        func specfile
-+
+        funcfile u v transform
-+
-+
+m A1 A2 .. Am
-+
+.DE
-+
+The function "func" is called with the interpolated pixel value
-+
+and the wavelength sample in nanometers, the same as specdata,
-+
+with as many calls made as there are components in "specfile".
+.NH 3
+Mixtures
+.PP
+in Lausanne, Switzerland.
+.NH 1
+References
-+
+.LP
-+
+Ward, Gregory J., Bruno Bueno, David Geisler-Moroder,
-+
+Lars O. Grobe, Jacob C. Jonsson, Eleanor
-+
+S. Lee, Taoning Wang, Helen Rose Wilson,
-+
+``Daylight Simulation Workflows Incorporating
-+
+Measured Bidirectional Scattering Distribution Functions,''
-+
+.I "Energy & Buildings",
-+
+Vol. 259, No. 111890, 2022.
+.LP
+Wang, Taoning, Gregory Ward, Eleanor Lee,
+``Efficient modeling of optically-complex, non-coplanar

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Comparing ray/doc/ray.1 (file contents): Revision 1.38 by greg, Mon Aug 31 21:54:55 2020 UTC vs. Revision 1.46 by greg, Wed Dec 13 23:26:16 2023 UTC

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Comparing ray/doc/ray.1 (file contents):
Revision 1.38 by greg, Mon Aug 31 21:54:55 2020 UTC vs.
Revision 1.46 by greg, Wed Dec 13 23:26:16 2023 UTC