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# Line 1 | Line 1
1   <html>
2 + <!-- RCSid $Id$ -->
3   <head>
4   <title>
5 < The RADIANCE 3.5 Synthetic Imaging System
5 > The RADIANCE 5.1 Synthetic Imaging System
6   </title>
7   </head>
8   <body>
9  
9 – Copyright � 2003 Regents, University of California
10 –
10   <p>
11  
12   <h1>
13 < The RADIANCE 3.5 Synthetic Imaging System
13 > The RADIANCE 5.1 Synthetic Imaging System
14   </h1>
15  
16   <p>
17  
18 < Building Technologies Department<br>
18 > Building Technologies Program<br>
19   Lawrence Berkeley National Laboratory<br>
20   1 Cyclotron Rd., 90-3111<br>
21   Berkeley, CA  94720<br>
# Line 566 | Line 565 | A material defines the way light interacts with a  sur
565          </a>
566  
567   <dd>
568 <        Mirror is used for planar surfaces that produce  secondary source reflections.  
568 >        Mirror is used for planar surfaces that produce  virtual source reflections.  
569          This material should be used sparingly, as it may cause the light source calculation to  blow up  if  it is applied to many small surfaces.  
570          This material is only supported for flat surfaces  such  as  <a HREF="#Polygon">polygons</a>  and <a HREF="#Ring">rings</a>.  
571          The arguments are simply the RGB reflectance values, which should be between 0 and 1.  
# Line 589 | Line 588 | This is only appropriate if the surface hides other (m
588          </a>
589  
590   <dd>
591 <        The prism1 material is for  general  light  redirection from prismatic glazings, generating secondary light sources.
591 >        The prism1 material is for  general  light  redirection from prismatic glazings, generating virtual light sources.
592          It can only be used  to  modify  a  planar  surface  
593          (i.e.,  a <a HREF="#Polygon">polygon</a>  or <a HREF="#Ring">disk</a>)
594          and should not result in either light concentration or scattering.  
595          The new direction of the ray  can be  on either side of the material,
596 <        and the definitions must have the correct bidirectional properties to  work  properly with  secondary light sources.  
596 >        and the definitions must have the correct bidirectional properties to  work  properly with virtual light sources.  
597          The arguments give the coefficient for the redirected light and its direction.
598  
599   <pre>
# Line 661 | Line 660 | a perfectly scattering medium (no absorption).
660   The scattering eccentricity parameter will likewise override the global
661   setting if it is present.
662   Scattering eccentricity indicates how much scattered light favors the
663 < forward direction, as fit by the Heyney-Greenstein function:
663 > forward direction, as fit by the Henyey-Greenstein function:
664  
665   <pre>
666          P(theta) = (1 - g*g) / (1 + g*g - 2*g*cos(theta))^1.5
# Line 1055 | Line 1054 | unless the line integrals consider enclosed geometry.
1054   <p>
1055  
1056   <dt>
1057 +        <a NAME="BSDF">
1058 +        <b>BSDF</b>
1059 +        </a>
1060 +
1061 + <dd>
1062 +        The BSDF material type loads an XML (eXtensible Markup Language)
1063 +        file describing a bidirectional scattering distribution function.
1064 +        Real arguments to this material may define additional
1065 +        diffuse components that augment the BSDF data.
1066 +        String arguments are used to define thickness for proxied
1067 +        surfaces and the &quot;up&quot; orientation for the material.
1068 +
1069 + <pre>
1070 +        mod BSDF id
1071 +        6+ thick BSDFfile ux uy uz funcfile transform
1072 +        0
1073 +        0|3|6|9
1074 +                rfdif gfdif bfdif
1075 +                rbdif gbdif bbdif
1076 +                rtdif gtdif btdif
1077 + </pre>
1078 +
1079 + <p>
1080 +        The first string argument is a &quot;thickness&quot; parameter that may be used
1081 +        to hide detail geometry being proxied by an aggregate BSDF material.
1082 +        If a view or shadow ray hits a BSDF proxy with non-zero thickness,
1083 +        it will pass directly through as if the surface were not there.
1084 +        Similar to the illum type, this permits direct viewing and
1085 +        shadow testing of complex geometry.
1086 +        The BSDF is used when a scattered (indirect) ray hits the surface,
1087 +        and any transmitted sample rays will be offset by the thickness amount
1088 +        to avoid the hidden geometry and gather samples from the other side.
1089 +        In this manner, BSDF surfaces can improve the results for indirect
1090 +        scattering from complex systems without sacrificing appearance or
1091 +        shadow accuracy.
1092 +        If the BSDF has transmission and back-side reflection data,
1093 +        a parallel BSDF surface may be
1094 +        placed slightly less than the given thickness away from the front surface
1095 +        to enclose the complex geometry on both sides.
1096 +        The sign of the thickness is important, as it indicates
1097 +        whether the proxied geometry is behind the BSDF
1098 +        surface (when thickness is positive) or in front (when
1099 +        thickness is negative).
1100 + <p>
1101 +        The second string argument is the name of the BSDF file,
1102 +        which is found in the usual auxiliary locations.  The
1103 +        following three string parameters name variables for an
1104 +        &quot;up&quot; vector, which together with the surface
1105 +        normal, define the local coordinate system that orients the
1106 +        BSDF.  These variables, along with the thickness, are defined
1107 +        in a function file given as the next string argument.  An
1108 +        optional transform is used to scale the thickness and
1109 +        reorient the up vector.
1110 + <p>
1111 +        If no real arguments are given, the BSDF is used by itself
1112 +        to determine reflection and transmission.  If there are at
1113 +        least 3 real arguments, the first triplet is an additional
1114 +        diffuse reflectance for the front side.  At least 6 real
1115 +        arguments adds diffuse reflectance to the rear side of the
1116 +        surface.  If there are 9 real arguments, the final triplet
1117 +        will be taken as an additional diffuse transmittance.  All
1118 +        diffuse components as well as the non-diffuse transmission
1119 +        are modified by patterns applied to this material.  The
1120 +        non-diffuse reflection from either side are unaffected.
1121 +        Textures perturb the effective surface normal in the usual
1122 +        way.
1123 + <p>
1124 +        The surface normal of this type is not altered to face the
1125 +        incoming ray, so the front and back BSDF reflections may
1126 +        differ.  (Transmission is identical front-to-back by physical
1127 +        law.) If back visibility is turned off during rendering and
1128 +        there is no transmission or back-side reflection, only then
1129 +        the surface will be invisible from behind.  Unlike other
1130 +        data-driven material types, the BSDF type is fully supported
1131 +        and all parts of the distribution are properly sampled.
1132 + <p>
1133 +
1134 + <dt>
1135          <a NAME="Antimatter">
1136          <b>Antimatter</b>
1137          </a>
# Line 1338 | Line 1415 | or:
1415   </h4>
1416  
1417   A mixture is a blend of one or more materials or textures and patterns.
1418 + Blended materials should not be light source types or virtual source types.
1419   The basic types are given below.
1420  
1421   <p>
# Line 1367 | Line 1445 | A mixfunc mixes  two  modifiers  procedurally.   It  i
1445          which serves as a form of opacity control when used with a material.)
1446          Vname is the coefficient defined in funcfile that determines  the  influence  of  foreground.  
1447          The background coefficient is always (1-vname).  
1370 –        Since the references are not resolved until run-time,  the  last  definitions  of  the modifier id's will be used.  
1371 –        This can result in modifier loops, which are detected by the renderer.
1448  
1449   <p>
1450  
# Line 1412 | Line 1488 | A mixfunc mixes  two  modifiers  procedurally.   It  i
1488          arguments, the red, green and blue values
1489          corresponding to the pixel at (u,v).
1490  
1415 – </dl>
1491   <p>
1492  
1493   <dt>
# Line 1530 | Line 1605 | If no file is needed by a given primitive because all
1605   the  required  variables  are global,  
1606   a  period  (`.')  can be given in place of the file name.  
1607   It is also possible to give an expression instead
1608 < of a  straight  variable  name  in  a scene file,
1609 < although such expressions should be kept
1535 < simple if possible.
1536 < Also, functions (requiring parameters) must be given
1608 > of a  straight  variable  name  in  a scene file.
1609 > Functions (requiring parameters) must be given
1610   as names and not as expressions.
1611  
1612   <p>
# Line 1716 | Line 1789 | Pictures may be displayed directly under X11 using the
1789   or converted a standard image format using one of the following
1790   <b>translators</b>:
1791          <ul>
1792 <        <li> <b>Ra_avs</b>
1793 <                converts to and from AVS image format.
1721 <        <li> <a HREF="../man_html/ra_pict.1.html"><b>Ra_pict</b></a>
1722 <                converts to Macintosh 32-bit PICT2 format.
1792 >        <li> <a HREF="../man_html/ra_bmp.1.html"><b>Ra_bmp</b>
1793 >                converts to and from BMP image format.
1794          <li> <a HREF="../man_html/ra_ppm.1.html"><b>Ra_ppm</b></a>
1795                  converts to and from Poskanzer Portable Pixmap formats.
1725 –        <li> <a HREF="../man_html/ra_pr.1.html"><b>Ra_pr</b></a>
1726 –                converts to and from Sun 8-bit rasterfile format.
1727 –        <li> <a HREF="../man_html/ra_pr24.1.html"><b>Ra_pr24</b></a>
1728 –                converts to and from Sun 24-bit rasterfile format.
1796          <li> <a HREF="../man_html/ra_ps.1.html"><b>Ra_ps</b></a>
1797                  converts to PostScript color and greyscale formats.
1798          <li> <a HREF="../man_html/ra_rgbe.1.html"><b>Ra_rgbe</b></a>
# Line 1751 | Line 1818 | or converted a standard image format using one of the
1818   <pre>
1819   The Radiance Software License, Version 1.0
1820  
1821 < Copyright (c) 1990 - 2002 The Regents of the University of California,
1821 > Copyright (c) 1990 - 2014 The Regents of the University of California,
1822   through Lawrence Berkeley National Laboratory.   All rights reserved.
1823  
1824   Redistribution and use in source and binary forms, with or without
# Line 1785 | Line 1852 | are met:
1852        nor may &quot;Radiance&quot; appear in their name, without prior written
1853        permission of Lawrence Berkeley National Laboratory.
1854  
1855 < THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
1855 > THIS SOFTWARE IS PROVIDED ``AS IS&quot; AND ANY EXPRESSED OR IMPLIED
1856   WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1857   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
1858   DISCLAIMED.   IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR
# Line 1824 | Line 1891 | Ecole  Polytechnique  Federale de Lausanne (EPFL Unive
1891   </h2>
1892   <p>
1893   <ul>
1894 +    <li>McNeil, A., C.J. Jonsson, D. Appelfeld, G. Ward, E.S. Lee,
1895 +        &quot;<a href="http://gaia.lbl.gov/btech/papers/4414.pdf">
1896 +        A validation of a ray-tracing tool used to generate
1897 +        bi-directional scattering distribution functions for
1898 +        complex fenestration systems</a>,&quot;
1899 +        <em>Solar Energy</em>, 98, 404-14,
1900 +        November 2013.
1901 +    <li>Ward, G., R. Mistrick, E.S. Lee, A. McNeil, J. Jonsson,
1902 +        &quot;<a href="http://gaia.lbl.gov/btech/papers/4414.pdf">Simulating
1903 +        the Daylight Performance of Complex Fenestration Systems
1904 +        Using Bidirectional Scattering Distribution Functions within
1905 +        Radiance</a>,&quot;
1906 +        <em>Leukos</em>, 7(4)
1907 +        April 2011.
1908 +    <li>Cater, Kirsten, Alan Chalmers, Greg Ward,
1909 +        &quot;<a href="http://www.anyhere.com/gward/papers/egsr2003.pdf">Detail to Attention:
1910 +        Exploiting Visual Tasks for Selective Rendering</a>,&quot;
1911 +        <em>Eurographics Symposium
1912 +        on Rendering 2003</em>, June 2003.
1913      <li>Ward, Greg, Elena Eydelberg-Vileshin,
1914 <        ``<a HREF="http://viz.cs.berkeley.edu/~gwlarson/papers/egwr02/index.html">Picture Perfect RGB
1915 <        Rendering Using Spectral Prefiltering and Sharp Color Primaries</a>,''
1914 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/egwr02/index.html">Picture Perfect RGB
1915 >        Rendering Using Spectral Prefiltering and Sharp Color Primaries</a>,&quot;
1916          Thirteenth Eurographics Workshop on Rendering (2002),
1917          P. Debevec and S. Gibson (Editors), June 2002.
1918      <li>Ward, Gregory,
1919 <        ``<a HREF="http://viz.cs.berkeley.edu/~gwlarson/papers/cic01.pdf">High Dynamic Range Imaging</a>,''
1919 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/cic01.pdf">High Dynamic Range Imaging</a>,&quot;
1920          Proceedings of the Ninth Color Imaging Conference, November 2001.
1921      <li>Ward, Gregory and Maryann Simmons,
1922 <        ``<a HREF="http://viz.cs.berkeley.edu/~gwlarson/papers/tog99.pdf">
1922 >        &quot;<a HREF="http://www.anyhere.com/gward/papers/tog99.pdf">
1923          The Holodeck Ray Cache: An Interactive Rendering System for Global Illumination in Nondiffuse
1924 <        Environments</a>,'' ACM Transactions on Graphics, 18(4):361-98, October 1999.
1925 <    <li>Larson, G.W., ``<a HREF="http://viz.cs.berkeley.edu/~gwlarson/papers/ewp98.pdf">The Holodeck: A Parallel
1926 <        Ray-caching Rendering System</a>,'' Proceedings of the Second
1924 >        Environments</a>,&quot; ACM Transactions on Graphics, 18(4):361-98, October 1999.
1925 >    <li>Larson, G.W., &quot;<a HREF="http://www.anyhere.com/gward/papers/ewp98.pdf">The Holodeck: A Parallel
1926 >        Ray-caching Rendering System</a>,&quot; Proceedings of the Second
1927          Eurographics Workshop on Parallel Graphics and Visualisation,
1928          September 1998.
1929      <li>Larson, G.W. and R.A. Shakespeare,
# Line 1845 | Line 1931 | Ecole  Polytechnique  Federale de Lausanne (EPFL Unive
1931          the Art and Science of Lighting Visualization</em></a>,
1932          Morgan Kaufmann Publishers, 1998.
1933      <li>Larson, G.W., H. Rushmeier, C. Piatko,
1934 <        ``<a HREF="http://radsite.lbl.gov/radiance/papers/lbnl39882/tonemap.pdf">A Visibility
1934 >        &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/lbnl39882/tonemap.pdf">A Visibility
1935          Matching Tone Reproduction Operator for
1936 <        High Dynamic Range Scenes</a>,'' LBNL Technical Report 39882,
1936 >        High Dynamic Range Scenes</a>,&quot; LBNL Technical Report 39882,
1937          January 1997.
1938 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw95.1/paper.html">Making
1939 <        Global Illumination User-Friendly</a>,'' Sixth
1938 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw95.1/paper.html">Making
1939 >        Global Illumination User-Friendly</a>,&quot; Sixth
1940          Eurographics Workshop on Rendering, Springer-Verlag,
1941          Dublin, Ireland, June 1995.</li>
1942      <li>Rushmeier, H., G. Ward, C. Piatko, P. Sanders, B. Rust,
1943 <        ``<a HREF="http://radsite.lbl.gov/mgf/compare.html">
1943 >        &quot;<a HREF="http://radsite.lbl.gov/mgf/compare.html">
1944          Comparing Real and Synthetic Images: Some Ideas about
1945 <        Metrics</a>,'' Sixth Eurographics Workshop on Rendering,
1945 >        Metrics</a>,&quot; Sixth Eurographics Workshop on Rendering,
1946          Springer-Verlag, Dublin, Ireland, June 1995.</li>
1947 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.1/paper.html">The RADIANCE
1948 <        Lighting Simulation and Rendering System</a>,'' <em>Computer
1947 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.1/paper.html">The RADIANCE
1948 >        Lighting Simulation and Rendering System</a>,&quot; <em>Computer
1949          Graphics</em>, July 1994.</li>
1950 <    <li>Rushmeier, H., G. Ward, ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.2/energy.html">Energy
1951 <        Preserving Non-Linear Filters</a>,'' <em>Computer
1950 >    <li>Rushmeier, H., G. Ward, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg94.2/energy.html">Energy
1951 >        Preserving Non-Linear Filters</a>,&quot; <em>Computer
1952          Graphics</em>, July 1994.</li>
1953 <    <li>Ward, G., ``A Contrast-Based Scalefactor for Luminance
1954 <        Display,'' <em>Graphics Gems IV</em>, Edited by Paul Heckbert,
1953 >    <li>Ward, G., &quot;A Contrast-Based Scalefactor for Luminance
1954 >        Display,&quot; <em>Graphics Gems IV</em>, Edited by Paul Heckbert,
1955          Academic Press 1994.</li>
1956 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg92/paper.html">Measuring and
1957 <        Modeling Anisotropic Reflection</a>,'' <em>Computer
1956 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg92/paper.html">Measuring and
1957 >        Modeling Anisotropic Reflection</a>,&quot; <em>Computer
1958          Graphics</em>, Vol. 26, No. 2, July 1992. </li>
1959 <    <li>Ward, G., P. Heckbert, ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw92/paper.html">Irradiance
1960 <        Gradients</a>,'' Third Annual Eurographics Workshop on
1959 >    <li>Ward, G., P. Heckbert, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw92/paper.html">Irradiance
1960 >        Gradients</a>,&quot; Third Annual Eurographics Workshop on
1961          Rendering, Springer-Verlag, May 1992. </li>
1962 <    <li>Ward, G., ``<a HREF="http://radsite.lbl.gov/radiance/papers/erw91/erw91.html">Adaptive Shadow
1963 <        Testing for Ray Tracing</a>'' Photorealistic Rendering in
1962 >    <li>Ward, G., &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/erw91/erw91.html">Adaptive Shadow
1963 >        Testing for Ray Tracing</a>&quot; Photorealistic Rendering in
1964          Computer Graphics, proceedings of 1991 Eurographics
1965          Rendering Workshop, edited by P. Brunet and F.W. Jansen,
1966          Springer-Verlag. </li>
1967 <    <li>Ward, G., ``Visualization,'' <em>Lighting Design and
1967 >    <li>Ward, G., &quot;Visualization,&quot; <em>Lighting Design and
1968          Application</em>, Vol. 20, No. 6, June 1990. </li>
1969 <    <li>Ward, G., F. Rubinstein, R. Clear, ``<a HREF="http://radsite.lbl.gov/radiance/papers/sg88/paper.html">A Ray Tracing Solution for
1970 <        Diffuse Interreflection</a>,'' <em>Computer Graphics</em>,
1969 >    <li>Ward, G., F. Rubinstein, R. Clear, &quot;<a HREF="http://radsite.lbl.gov/radiance/papers/sg88/paper.html">A Ray Tracing Solution for
1970 >        Diffuse Interreflection</a>,&quot; <em>Computer Graphics</em>,
1971          Vol. 22, No. 4, August 1988. </li>
1972 <    <li>Ward, G., F. Rubinstein, ``A New Technique for Computer
1973 <        Simulation of Illuminated Spaces,'' <em>Journal of the
1972 >    <li>Ward, G., F. Rubinstein, &quot;A New Technique for Computer
1973 >        Simulation of Illuminated Spaces,&quot; <em>Journal of the
1974          Illuminating Engineering Society</em>, Vol. 17, No. 1,
1975          Winter 1988. </li>
1976   </ul>
# Line 1922 | Line 2008 | SURFACES       MATERIALS       TEXTURES        PATTERNS        MIXTURES</h4>
2008                  <a HREF="#Plasdata">Plasdata</a>
2009                  <a HREF="#Metdata">Metdata</a>
2010                  <a HREF="#Transdata">Transdata</a>
2011 +                <a HREF="#BSDF">BSDF</a>
2012                  <a HREF="#Antimatter">Antimatter</a>
2013                                  
2014   </pre>

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