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# Line 1 | Line 1
1   <html>
2 + <!-- RCSid $Id$ -->
3   <head>
4   <title>
5 < The RADIANCE 4.1 Synthetic Imaging System
5 > The RADIANCE 6.0 Synthetic Imaging System
6   </title>
7   </head>
8   <body>
# Line 9 | Line 10 | The RADIANCE 4.1 Synthetic Imaging System
10   <p>
11  
12   <h1>
13 < The RADIANCE 4.1 Synthetic Imaging System
13 > The RADIANCE 6.0 Synthetic Imaging System
14   </h1>
15  
16   <p>
# Line 82 | Line 83 | The diagram in Figure 1 shows the flow between program
83   (ovals).  
84   The central program is <i>rpict</i>, which produces a picture from a scene
85   description.
86 < <i>Rview</i> is a  variation  of  rpict  that  computes  and displays images
86 > <i>Rvu</i> is a  variation  of  rpict  that  computes  and displays images
87   interactively, and rtrace computes single ray values.
88   Other programs (not shown) connect many of these elements together,
89   such as the executive programs
# Line 797 | Line 798 | unless the line integrals consider enclosed geometry.
798  
799   <dd>
800          Trans2 is the anisotropic version of <a HREF="#Trans">trans</a>.  
801 <        The string arguments  are  the same as for plastic2, and the real arguments are the same as  for  trans  but  with  an  additional roughness value.
801 >        The string arguments  are  the same as for <a HREF="#Plastic2">plastic2</a>,
802 >        and the real arguments are the same as  for  trans  but  with  an  additional roughness value.
803  
804   <pre>
805          mod trans2 id
# Line 809 | Line 811 | unless the line integrals consider enclosed geometry.
811   <p>
812  
813   <dt>
814 +        <a NAME="Ashik2">
815 +        <b>Ashik2</b>
816 +        </a>
817 +
818 + <dd>
819 +        Ashik2 is the anisotropic reflectance model by Ashikhmin & Shirley.
820 +        The string arguments are the same as for <a HREF="#Plastic2">plastic2</a>, but the real
821 +        arguments have additional flexibility to specify the specular color.
822 +        Also, rather than roughness, specular power is used, which has no
823 +        physical meaning other than larger numbers are equivalent to a smoother
824 +        surface.
825 +        Unlike other material types, total reflectance is the sum of
826 +        diffuse and specular colors, and should be adjusted accordingly.
827 + <pre>
828 +        mod ashik2 id
829 +        4+ ux uy uz funcfile transform
830 +        0
831 +        8 dred dgrn dblu sred sgrn sblu u-power v-power
832 + </pre>
833 +
834 + <p>
835 +
836 + <dt>
837          <a NAME="Dielectric">
838          <b>Dielectric</b>
839          </a>
# Line 1093 | Line 1118 | unless the line integrals consider enclosed geometry.
1118          placed slightly less than the given thickness away from the front surface
1119          to enclose the complex geometry on both sides.
1120          The sign of the thickness is important, as it indicates
1121 <        whether the proxied geometry is behind the <em>BSDF</em>
1121 >        whether the proxied geometry is behind the BSDF
1122          surface (when thickness is positive) or in front (when
1123          thickness is negative).
1124   <p>
# Line 1131 | Line 1156 | unless the line integrals consider enclosed geometry.
1156   <p>
1157  
1158   <dt>
1159 +        <a NAME="aBSDF">
1160 +        <b>aBSDF</b>
1161 +        </a>
1162 +
1163 + <dd>
1164 +        The aBSDF material is identical to the BSDF type with two
1165 +        important differences.  First, proxy geometry is not
1166 +        supported, so there is no thickness parameter.  Second, an
1167 +        aBSDF is assumed to have some specular through component
1168 +        (the &rsquo;a&rsquo; stands for &quot;aperture&quot;),
1169 +        which is treated specially during the direct calculation
1170 +        and when viewing the material.  Based on the BSDF data, the
1171 +        coefficient of specular transmission is determined and used
1172 +        for modifying unscattered shadow and view rays.
1173 +
1174 + <pre>
1175 +        mod aBSDF id
1176 +        5+ BSDFfile ux uy uz funcfile transform
1177 +        0
1178 +        0|3|6|9
1179 +             rfdif gfdif bfdif
1180 +             rbdif gbdif bbdif
1181 +             rtdif gtdif btdif
1182 + </pre>
1183 +
1184 + <p>
1185 +        If a material has no specular transmitted component, it is
1186 +        much better to use the BSDF type with a zero thickness
1187 +        than to use aBSDF.
1188 + <p>
1189 +
1190 + <dt>
1191          <a NAME="Antimatter">
1192          <b>Antimatter</b>
1193          </a>
# Line 1404 | Line 1461 | or:
1461          A section of text meant to  depict  a  picture, perhaps using a special purpose font such as hexbit4x1.fnt, calls for uniform  spacing.  
1462          Reasonable  magnitudes  for  proportional  spacing are between 0.1 (for tightly spaced characters) and 0.3 (for wide spacing).
1463  
1464 + <p>
1465 +
1466 + <dt>
1467 +        <a NAME="Spectrum">
1468 +        <b>Spectrum</b>
1469 +        </a>
1470 +
1471 + <dd>
1472 +        The spectrum primitive is the most basic type for introducing spectral
1473 +        color to a material.
1474 +        Since materials only provide RGB parameters, spectral patterns
1475 +        are the only way to superimpose wavelength-dependent behavior.
1476 +
1477 + <pre>
1478 +        mod spectrum id
1479 +        0
1480 +        0
1481 +        5+ nmA nmB s1 s2 .. sN
1482 + </pre>
1483 +
1484 + <p>
1485 +        The first two real arguments indicate the extrema of the
1486 +        spectral range in nanometers.
1487 +        Subsequent real values correspond to multipliers in at each wavelength.
1488 +        The nmA wavelength may be greater or less than nmB,
1489 +        but they may not be equal, and their ordering matches
1490 +        the order of the spectral values.
1491 +        A minimum of 3 values must be given, which would act
1492 +        more or less the same as a constant RGB multiplier.
1493 +        As with RGB values, spectral quantities normally range between 0
1494 +        and 1 at each wavelength, or average to 1.0 against a standard
1495 +        sensitivity functions such as V(lambda).
1496 +        The best results obtain when the spectral range and number
1497 +        of samples match rendering options, though resampling will handle
1498 +        any differences, zero-filling wavelenths outside the nmA to nmB
1499 +        range.
1500 +        A warning will be issued if the given wavelength range does not
1501 +        adequately cover the visible spectrum.
1502 +
1503 + <p>
1504 +
1505 + <dt>
1506 +        <a NAME="Specfile">
1507 +        <b>Specfile</b>
1508 +        </a>
1509 +
1510 + <dd>
1511 +        The specfile primitive is equivalent to the spectrum type, but
1512 +        the wavelength range and values are contained in a 1-dimensional
1513 +        data file.
1514 +        This may be a more convenient way to specify a spectral color,
1515 +        especially one corresponding to a standard illuminant such as D65
1516 +        or a library of measured spectra.
1517 +
1518 + <pre>
1519 +        mod specfile id
1520 +        1 datafile
1521 +        0
1522 +        0
1523 + </pre>
1524 +
1525 + <p>
1526 +        As with the spectrum type, rendering wavelengths outside the defined
1527 +        range will be zero-filled.
1528 +        Unlike the spectrum type, the file may contain non-uniform samples.
1529 +
1530 + <p>
1531 +
1532 + <dt>
1533 +        <a NAME="Specfunc">
1534 +        <b>Specfunc</b>
1535 +        </a>
1536 +
1537 + <dd>
1538 +        The specfunc primitive offers dynamic control over a spectral
1539 +        pattern, similar to the colorfunc type.
1540 +
1541 + <pre>
1542 +        mod specfunc id
1543 +        2+ sval funcfile transform
1544 +        0
1545 +        2+ nmA nmB A3 ..
1546 + </pre>
1547 +
1548 + <p>
1549 +        Like the spectrum primitive, the wavelength range is specified
1550 +        in the first two real arguments, and additional real values are
1551 +        accessible to the sval function.
1552 +        This function is fed a wavelenth sample
1553 +        between nmA and nmB as its only argument,
1554 +        and it returns the corresponding spectral intensity.
1555 +
1556   </dl>
1557  
1558   <p>
# Line 1414 | Line 1563 | or:
1563   </h4>
1564  
1565   A mixture is a blend of one or more materials or textures and patterns.
1566 + Blended materials should not be light source types or virtual source types.
1567   The basic types are given below.
1568  
1569   <p>
# Line 1486 | Line 1636 | A mixfunc mixes  two  modifiers  procedurally.   It  i
1636          arguments, the red, green and blue values
1637          corresponding to the pixel at (u,v).
1638  
1489 – </dl>
1639   <p>
1640  
1641   <dt>
# Line 1752 | Line 1901 | The details of this process  are  not  important, but
1901   directs the use of a scene description.
1902   <ul>
1903   <li>
1904 < <a NAME="rvu" HREF="../man_html/rvu.1.html"><b>Rview</b></a>  is  ray-tracing  program  for  viewing  a  scene interactively.  
1904 > <a NAME="rvu" HREF="../man_html/rvu.1.html"><b>Rvu</b></a>  is  ray-tracing  program  for  viewing  a  scene interactively.  
1905   When  the user specifies a new perspective, rvu quickly displays a rough image on the  terminal,  
1906   then progressively increases the resolution as the user looks on.
1907   He can select a particular section of the image to  improve, or  move  to  a different view and start over.  
# Line 1788 | Line 1937 | Pictures may be displayed directly under X11 using the
1937   or converted a standard image format using one of the following
1938   <b>translators</b>:
1939          <ul>
1940 <        <li> <b>Ra_avs</b>
1941 <                converts to and from AVS image format.
1793 <        <li> <a HREF="../man_html/ra_pict.1.html"><b>Ra_pict</b></a>
1794 <                converts to Macintosh 32-bit PICT2 format.
1940 >        <li> <a HREF="../man_html/ra_bmp.1.html"><b>Ra_bmp</b></a>
1941 >                converts to and from BMP image format.
1942          <li> <a HREF="../man_html/ra_ppm.1.html"><b>Ra_ppm</b></a>
1943                  converts to and from Poskanzer Portable Pixmap formats.
1797 –        <li> <a HREF="../man_html/ra_pr.1.html"><b>Ra_pr</b></a>
1798 –                converts to and from Sun 8-bit rasterfile format.
1799 –        <li> <a HREF="../man_html/ra_pr24.1.html"><b>Ra_pr24</b></a>
1800 –                converts to and from Sun 24-bit rasterfile format.
1944          <li> <a HREF="../man_html/ra_ps.1.html"><b>Ra_ps</b></a>
1945                  converts to PostScript color and greyscale formats.
1946          <li> <a HREF="../man_html/ra_rgbe.1.html"><b>Ra_rgbe</b></a>
# Line 1823 | Line 1966 | or converted a standard image format using one of the
1966   <pre>
1967   The Radiance Software License, Version 1.0
1968  
1969 < Copyright (c) 1990 - 2010 The Regents of the University of California,
1969 > Copyright (c) 1990 - 2021 The Regents of the University of California,
1970   through Lawrence Berkeley National Laboratory.   All rights reserved.
1971  
1972   Redistribution and use in source and binary forms, with or without
# Line 1857 | Line 2000 | are met:
2000        nor may &quot;Radiance&quot; appear in their name, without prior written
2001        permission of Lawrence Berkeley National Laboratory.
2002  
2003 < THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
2003 > THIS SOFTWARE IS PROVIDED ``AS IS&quot; AND ANY EXPRESSED OR IMPLIED
2004   WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
2005   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
2006   DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
# Line 1896 | Line 2039 | Ecole  Polytechnique  Federale de Lausanne (EPFL Unive
2039   </h2>
2040   <p>
2041   <ul>
2042 +    <li>Ward, Gregory J., Bruno Bueno, David Geisler-Moroder,
2043 +      Lars O. Grobe, Jacob C. Jonsson, Eleanor
2044 +      S. Lee, Taoning Wang, Helen Rose Wilson,
2045 +      &quot;<a href="https://doi.org/10.1016/j.enbuild.2022.111890">Daylight
2046 +      Simulation Workflows Incorporating Measured Bidirectional
2047 +      Scattering Distribution Functions</a>&quot;
2048 +      <em>Energy &amp; Buildings</em>, Vol. 259, No. 11890, 2022.
2049 +    <li>Wang, Taoning, Gregory Ward, Eleanor Lee,
2050 +      &quot;<a href="https://authors.elsevier.com/a/1XQ0a1M7zGwT7v">Efficient
2051 +      modeling of optically-complex, non-coplanar exterior shading:
2052 +      Validation of matrix algebraic methods</a>&quot;
2053 +      <em>Energy & Buildings</em>, vol. 174, pp. 464-83, Sept. 2018.
2054 +    <li>Lee, Eleanor S., David Geisler-Moroder, Gregory Ward,
2055 +      &quot;<a href="https://eta.lbl.gov/sites/default/files/publications/solar_energy.pdf">Modeling
2056 +      the direct sun component in buildings using matrix
2057 +      algebraic approaches: Methods and
2058 +      validation</a>,&quot; <em>Solar Energy</em>,
2059 +      vol. 160, 15 January 2018, pp 380-395.
2060 +    <li>Narain, Rahul, Rachel A. Albert, Abdullah Bulbul,
2061 +       Gregory J. Ward, Marty Banks, James F. O'Brien,
2062 +       &quot;<a href="http://graphics.berkeley.edu/papers/Narain-OPI-2015-08/index.html">Optimal
2063 +       Presentation of Imagery with Focus
2064 +       Cues on Multi-Plane Displays</a>,&quot;
2065 +       <em>SIGGRAPH 2015</em>.
2066 +    <li>Ward, Greg, Murat Kurt, and Nicolas Bonneel,
2067 +        &quot;<a href="papers/WMAM14_Tensor_Tree_Representation.pdf">Reducing
2068 +        Anisotropic BSDF Measurement to Common Practice</a>,&quot;
2069 +        <em>Workshop on Material Appearance Modeling</em>, 2014.
2070 +    <li>Banks, Martin, Abdullah Bulbul, Rachel Albert, Rahul Narain,
2071 +        James F. O'Brien, Gregory Ward,
2072 +        &quot;<a href="http://graphics.berkeley.edu/papers/Banks-TPO-2014-05/index.html">The
2073 +        Perception of Surface Material from Disparity and Focus Cues</a>,&quot;
2074 +        <em>VSS 2014</em>.
2075 +    <li>McNeil, A., C.J. Jonsson, D. Appelfeld, G. Ward, E.S. Lee,
2076 +        &quot;<a href="http://gaia.lbl.gov/btech/papers/4414.pdf">
2077 +        A validation of a ray-tracing tool used to generate
2078 +        bi-directional scattering distribution functions for
2079 +        complex fenestration systems</a>,&quot;
2080 +        <em>Solar Energy</em>, 98, 404-14,
2081 +        November 2013.
2082 +    <li>Ward, G., R. Mistrick, E.S. Lee, A. McNeil, J. Jonsson,
2083 +        &quot;<a href="http://gaia.lbl.gov/btech/papers/4414.pdf">Simulating
2084 +        the Daylight Performance of Complex Fenestration Systems
2085 +        Using Bidirectional Scattering Distribution Functions within
2086 +        Radiance</a>,&quot;
2087 +        <em>Leukos</em>, 7(4)
2088 +        April 2011.
2089      <li>Cater, Kirsten, Alan Chalmers, Greg Ward,
2090          &quot;<a href="http://www.anyhere.com/gward/papers/egsr2003.pdf">Detail to Attention:
2091          Exploiting Visual Tasks for Selective Rendering</a>,&quot;
2092          <em>Eurographics Symposium
2093          on Rendering 2003</em>, June 2003.
2094      <li>Ward, Greg, Elena Eydelberg-Vileshin,
2095 <        ``<a HREF="http://www.anyhere.com/gward/papers/egwr02/index.html">Picture Perfect RGB
2096 <        Rendering Using Spectral Prefiltering and Sharp Color Primaries</a>,''
2095 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/egwr02/index.html">Picture Perfect RGB
2096 >        Rendering Using Spectral Prefiltering and Sharp Color Primaries</a>,&quot;
2097          Thirteenth Eurographics Workshop on Rendering (2002),
2098          P. Debevec and S. Gibson (Editors), June 2002.
2099      <li>Ward, Gregory,
2100 <        ``<a HREF="http://www.anyhere.com/gward/papers/cic01.pdf">High Dynamic Range Imaging</a>,''
2100 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/cic01.pdf">High Dynamic Range Imaging</a>,&quot;
2101          Proceedings of the Ninth Color Imaging Conference, November 2001.
2102      <li>Ward, Gregory and Maryann Simmons,
2103 <        ``<a HREF="http://www.anyhere.com/gward/papers/tog99.pdf">
2103 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/tog99.pdf">
2104          The Holodeck Ray Cache: An Interactive Rendering System for Global Illumination in Nondiffuse
2105 <        Environments</a>,'' ACM Transactions on Graphics, 18(4):361-98, October 1999.
2106 <    <li>Larson, G.W., ``<a HREF="http://www.anyhere.com/gward/papers/ewp98.pdf">The Holodeck: A Parallel
2107 <        Ray-caching Rendering System</a>,'' Proceedings of the Second
2105 >        Environments</a>,&quot; ACM Transactions on Graphics, 18(4):361-98, October 1999.
2106 >    <li>Larson, G.W., &quot;<a HREF="http://www.anyhere.com/gward/papers/ewp98.pdf">The Holodeck: A Parallel
2107 >        Ray-caching Rendering System</a>,&quot; Proceedings of the Second
2108          Eurographics Workshop on Parallel Graphics and Visualisation,
2109          September 1998.
2110      <li>Larson, G.W. and R.A. Shakespeare,
# Line 1922 | Line 2112 | Ecole  Polytechnique  Federale de Lausanne (EPFL Unive
2112          the Art and Science of Lighting Visualization</em></a>,
2113          Morgan Kaufmann Publishers, 1998.
2114      <li>Larson, G.W., H. Rushmeier, C. Piatko,
2115 <        ``<a HREF="http://radsite.lbl.gov/radiance/papers/lbnl39882/tonemap.pdf">A Visibility
2115 >        &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/lbnl39882/tonemap.pdf">A Visibility
2116          Matching Tone Reproduction Operator for
2117 <        High Dynamic Range Scenes</a>,'' LBNL Technical Report 39882,
2117 >        High Dynamic Range Scenes</a>,&quot; LBNL Technical Report 39882,
2118          January 1997.
2119 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw95.1/paper.html">Making
2120 <        Global Illumination User-Friendly</a>,'' Sixth
2119 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw95.1/paper.html">Making
2120 >        Global Illumination User-Friendly</a>,&quot; Sixth
2121          Eurographics Workshop on Rendering, Springer-Verlag,
2122          Dublin, Ireland, June 1995.</li>
2123      <li>Rushmeier, H., G. Ward, C. Piatko, P. Sanders, B. Rust,
2124 <        ``<a HREF="http://radsite.lbl.gov/mgf/compare.html">
2124 >        &quot;<a HREF="http://radsite.lbl.gov/mgf/compare.html">
2125          Comparing Real and Synthetic Images: Some Ideas about
2126 <        Metrics</a>,'' Sixth Eurographics Workshop on Rendering,
2126 >        Metrics</a>,&quot; Sixth Eurographics Workshop on Rendering,
2127          Springer-Verlag, Dublin, Ireland, June 1995.</li>
2128 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.1/paper.html">The RADIANCE
2129 <        Lighting Simulation and Rendering System</a>,'' <em>Computer
2128 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.1/paper.html">The RADIANCE
2129 >        Lighting Simulation and Rendering System</a>,&quot; <em>Computer
2130          Graphics</em>, July 1994.</li>
2131 <    <li>Rushmeier, H., G. Ward, ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.2/energy.html">Energy
2132 <        Preserving Non-Linear Filters</a>,'' <em>Computer
2131 >    <li>Rushmeier, H., G. Ward, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.2/energy.html">Energy
2132 >        Preserving Non-Linear Filters</a>,&quot; <em>Computer
2133          Graphics</em>, July 1994.</li>
2134 <    <li>Ward, G., ``A Contrast-Based Scalefactor for Luminance
2135 <        Display,'' <em>Graphics Gems IV</em>, Edited by Paul Heckbert,
2134 >    <li>Ward, G., &quot;A Contrast-Based Scalefactor for Luminance
2135 >        Display,&quot; <em>Graphics Gems IV</em>, Edited by Paul Heckbert,
2136          Academic Press 1994.</li>
2137 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg92/paper.html">Measuring and
2138 <        Modeling Anisotropic Reflection</a>,'' <em>Computer
2137 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg92/paper.html">Measuring and
2138 >        Modeling Anisotropic Reflection</a>,&quot; <em>Computer
2139          Graphics</em>, Vol. 26, No. 2, July 1992. </li>
2140 <    <li>Ward, G., P. Heckbert, ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw92/paper.html">Irradiance
2141 <        Gradients</a>,'' Third Annual Eurographics Workshop on
2140 >    <li>Ward, G., P. Heckbert, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw92/paper.html">Irradiance
2141 >        Gradients</a>,&quot; Third Annual Eurographics Workshop on
2142          Rendering, Springer-Verlag, May 1992. </li>
2143 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw91/erw91.html">Adaptive Shadow
2144 <        Testing for Ray Tracing</a>'' Photorealistic Rendering in
2143 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw91/erw91.html">Adaptive Shadow
2144 >        Testing for Ray Tracing</a>&quot; Photorealistic Rendering in
2145          Computer Graphics, proceedings of 1991 Eurographics
2146          Rendering Workshop, edited by P. Brunet and F.W. Jansen,
2147          Springer-Verlag. </li>
2148 <    <li>Ward, G., ``Visualization,'' <em>Lighting Design and
2148 >    <li>Ward, G., &quot;Visualization,&quot; <em>Lighting Design and
2149          Application</em>, Vol. 20, No. 6, June 1990. </li>
2150 <    <li>Ward, G., F. Rubinstein, R. Clear, ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg88/paper.html">A Ray Tracing Solution for
2151 <        Diffuse Interreflection</a>,'' <em>Computer Graphics</em>,
2150 >    <li>Ward, G., F. Rubinstein, R. Clear, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg88/paper.html">A Ray Tracing Solution for
2151 >        Diffuse Interreflection</a>,&quot; <em>Computer Graphics</em>,
2152          Vol. 22, No. 4, August 1988. </li>
2153 <    <li>Ward, G., F. Rubinstein, ``A New Technique for Computer
2154 <        Simulation of Illuminated Spaces,'' <em>Journal of the
2153 >    <li>Ward, G., F. Rubinstein, &quot;A New Technique for Computer
2154 >        Simulation of Illuminated Spaces,&quot; <em>Journal of the
2155          Illuminating Engineering Society</em>, Vol. 17, No. 1,
2156          Winter 1988. </li>
2157   </ul>

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