| 75 |
|
computer-aided engineering and architecture. |
| 76 |
|
|
| 77 |
|
<p> |
| 78 |
< |
<img SRC="diagram1.gif"> |
| 78 |
> |
<img SRC="diagram1.png"> |
| 79 |
|
<p> |
| 80 |
– |
Figure 1 |
| 81 |
– |
<p> |
| 80 |
|
The diagram in Figure 1 shows the flow between programs (boxes) and data |
| 81 |
|
(ovals). |
| 82 |
|
The central program is <i>rpict</i>, which produces a picture from a scene |
| 146 |
|
... |
| 147 |
|
</pre> |
| 148 |
|
|
| 149 |
+ |
<p> |
| 150 |
+ |
|
| 151 |
|
A comment line begins with a pound sign, `#'. |
| 152 |
|
|
| 153 |
|
<p> |
| 394 |
|
0 |
| 395 |
|
</pre> |
| 396 |
|
|
| 397 |
+ |
<p> |
| 398 |
|
If the modifier is "void", then surfaces will |
| 399 |
|
use the modifiers given in the original description. |
| 400 |
|
Otherwise, the modifier specified is used in their place. |
| 439 |
|
0 |
| 440 |
|
</pre> |
| 441 |
|
|
| 442 |
+ |
<p> |
| 443 |
+ |
|
| 444 |
|
If the modifier is "void", then surfaces will |
| 445 |
|
use the modifiers given in the original mesh description. |
| 446 |
|
Otherwise, the modifier specified is used in their place. |
| 535 |
|
4 red green blue maxrad |
| 536 |
|
</pre> |
| 537 |
|
|
| 538 |
+ |
<p> |
| 539 |
|
If maxrad is zero, then the surface will never be tested for shadow, although it may participate in an interreflection calculation. |
| 540 |
|
If maxrad is negative, then the surface will never contribute to scene illumination. |
| 541 |
|
Glow sources will never illuminate objects on the other side of an illum surface. |
| 584 |
|
3 red green blue |
| 585 |
|
</pre> |
| 586 |
|
|
| 587 |
+ |
While alternate materials that are reflective will appear as normal, |
| 588 |
+ |
indirect rays will use the mirror's reflectance rather than the |
| 589 |
+ |
alternate type. |
| 590 |
+ |
Transmitting materials are an exception, where both transmission and |
| 591 |
+ |
reflection will use the alternate type for all rays not specifically |
| 592 |
+ |
targeting virtual light sources. |
| 593 |
+ |
In this case, it is important that any reflections be purely specular |
| 594 |
+ |
(mirror-like) and equal to the mirror's reflectivity |
| 595 |
+ |
to maintain a valid result. |
| 596 |
+ |
A pure diffuse reflection may be added if desired. |
| 597 |
+ |
|
| 598 |
|
<p> |
| 599 |
|
|
| 600 |
+ |
The mirror material type reflects light sources only from the front side |
| 601 |
+ |
of a surface, regardless of any alternate material. |
| 602 |
+ |
If virtual source generation is desired on both sides, two coincident |
| 603 |
+ |
surfaces with opposite normal orientations may be employed to achieve |
| 604 |
+ |
this effect. |
| 605 |
+ |
The reflectance and alternate material type may be |
| 606 |
+ |
different for the overlapped surfaces, |
| 607 |
+ |
and the two sides will behave accordingly. |
| 608 |
+ |
|
| 609 |
+ |
<p> |
| 610 |
+ |
|
| 611 |
|
<dt> |
| 612 |
|
<a NAME="Prism1"> |
| 613 |
|
<b>Prism1</b> |
| 629 |
|
n A1 A2 .. An |
| 630 |
|
</pre> |
| 631 |
|
|
| 632 |
+ |
<p> |
| 633 |
+ |
|
| 634 |
|
The new direction variables dx, dy and dz need not produce a normalized vector. |
| 635 |
|
For convenience, the variables DxA, DyA and DzA are defined as the normalized direction to the target light source. |
| 636 |
|
See <a HREF="#Function">section 2.2.1</a> on function files for further information. |
| 674 |
|
3 source1 mirror1>source10 mirror2>mirror1>source3 |
| 675 |
|
</pre> |
| 676 |
|
|
| 677 |
+ |
<p> |
| 678 |
|
Normally, only one source is given per mist material, and there is an |
| 679 |
|
upper limit of 32 to the total number of active scattering sources. |
| 680 |
|
The extinction coefficient, if given, is added the the global |
| 695 |
|
P(theta) = (1 - g*g) / (1 + g*g - 2*g*cos(theta))^1.5 |
| 696 |
|
</pre> |
| 697 |
|
|
| 698 |
+ |
<p> |
| 699 |
+ |
|
| 700 |
|
A perfectly isotropic scattering medium has a g parameter of 0, and |
| 701 |
|
a highly directional material has a g parameter close to 1. |
| 702 |
|
Fits to the g parameter may be found along with typical extinction |
| 711 |
|
0|3|6|7 [ rext gext bext [ ralb galb balb [ g ] ] ] |
| 712 |
|
</pre> |
| 713 |
|
|
| 714 |
+ |
<p> |
| 715 |
+ |
|
| 716 |
|
There are two usual uses of the mist type. |
| 717 |
|
One is to surround a beam from a spotlight or laser so that it is |
| 718 |
|
visible during rendering. |
| 890 |
|
A10 .. |
| 891 |
|
</pre> |
| 892 |
|
|
| 893 |
+ |
<p> |
| 894 |
+ |
|
| 895 |
|
The sum of specular reflectance (<I>rs</I>), specular transmittance (<I>ts</I>), |
| 896 |
|
diffuse reflectance (<I>rfdif gfdif bfdif</I> for front and <I>rbdif gbdif bbdif</I> for back) |
| 897 |
|
and diffuse transmittance (<I>rtdif gtdif btdif</I>) should be less than 1 for each |
| 985 |
|
tn = (sqrt(.8402528435+.0072522239*Tn*Tn)-.9166530661)/.0036261119/Tn |
| 986 |
|
</pre> |
| 987 |
|
|
| 988 |
+ |
<p> |
| 989 |
+ |
|
| 990 |
|
Standard 88% transmittance glass has a transmissivity of 0.96. |
| 991 |
|
(A <a HREF="#Patterns">pattern</a> modifying glass will affect the transmissivity.) |
| 992 |
|
If a fourth real argument is given, it is interpreted as the index of refraction to use instead of 1.52. |
| 1018 |
|
4+ red green blue spec A5 .. |
| 1019 |
|
</pre> |
| 1020 |
|
|
| 1021 |
+ |
<p> |
| 1022 |
+ |
|
| 1023 |
|
The function refl takes four arguments, the x, y and z |
| 1024 |
|
direction towards the incident light, and the solid angle |
| 1025 |
|
subtended by the source. |
| 1061 |
|
6+ red green blue rspec trans tspec A7 .. |
| 1062 |
|
</pre> |
| 1063 |
|
|
| 1064 |
+ |
<p> |
| 1065 |
+ |
|
| 1066 |
|
Where trans is the total light transmitted and tspec is the non-Lambertian fraction of transmitted light. |
| 1067 |
|
The function brtd should integrate to 1 over each projected hemisphere. |
| 1068 |
|
|
| 1090 |
|
A10 .. |
| 1091 |
|
</pre> |
| 1092 |
|
|
| 1093 |
+ |
<p> |
| 1094 |
+ |
|
| 1095 |
|
The variables rrefl, grefl and brefl specify the color coefficients for the ideal specular (mirror) reflection of the surface. |
| 1096 |
|
The variables rtrns, gtrns and btrns specify the color coefficients for the ideal specular transmission. |
| 1097 |
|
The functions rbrtd, gbrtd and bbrtd take the direction to the incident light (and its solid angle) and |
| 1136 |
|
4+ red green blue spec A5 .. |
| 1137 |
|
</pre> |
| 1138 |
|
|
| 1139 |
+ |
<p> |
| 1140 |
+ |
|
| 1141 |
|
The coordinate indices (x1, x2, etc.) are themselves functions of the x, y and z direction to the incident light, plus the solid angle |
| 1142 |
|
subtended by the light source (usually ignored). |
| 1143 |
|
The data function (func) takes five variables, the |
| 1304 |
|
0 |
| 1305 |
|
</pre> |
| 1306 |
|
|
| 1307 |
+ |
<p> |
| 1308 |
+ |
|
| 1309 |
|
The first modifier will also be used to shade the area leaving the antimatter volume and entering the regular volume. |
| 1310 |
|
If mod1 is void, the antimatter volume is completely invisible. |
| 1311 |
|
Antimatter does not work properly with the material type <a HREF="#Trans">"trans"</a>, |
| 1355 |
|
|
| 1356 |
|
<pre> |
| 1357 |
|
mod texdata id |
| 1358 |
< |
8+ xfunc yfunc zfunc xdfname ydfname zdfname vfname x0 x1 .. xf |
| 1358 |
> |
8+ xfunc yfunc zfunc xdfname ydfname zdfname funcfile x0 x1 .. xf |
| 1359 |
|
0 |
| 1360 |
|
n A1 A2 .. An |
| 1361 |
|
</pre> |
| 1362 |
|
|
| 1363 |
+ |
<p> |
| 1364 |
+ |
|
| 1365 |
|
</dl> |
| 1366 |
|
|
| 1367 |
|
<p> |
| 1501 |
|
[spacing] |
| 1502 |
|
</pre> |
| 1503 |
|
|
| 1504 |
+ |
<p> |
| 1505 |
+ |
|
| 1506 |
|
or: |
| 1507 |
|
|
| 1508 |
|
<pre> |
| 1540 |
|
[spacing] |
| 1541 |
|
</pre> |
| 1542 |
|
|
| 1543 |
+ |
<p> |
| 1544 |
+ |
|
| 1545 |
|
or: |
| 1546 |
|
|
| 1547 |
|
<pre> |
| 1749 |
|
n A1 A2 .. An |
| 1750 |
|
</pre> |
| 1751 |
|
|
| 1752 |
+ |
<p> |
| 1753 |
+ |
|
| 1754 |
|
Foreground and background are modifier names that must be |
| 1755 |
|
defined earlier in the scene description. |
| 1756 |
|
If one of these is a material, then |
| 1779 |
|
m A1 A2 .. Am |
| 1780 |
|
</pre> |
| 1781 |
|
|
| 1782 |
+ |
<p> |
| 1783 |
+ |
|
| 1784 |
|
<dt> |
| 1785 |
|
<a NAME="Mixpict"> |
| 1786 |
|
<b>Mixpict</b> |
| 1825 |
|
[spacing] |
| 1826 |
|
</pre> |
| 1827 |
|
|
| 1828 |
+ |
<p> |
| 1829 |
+ |
|
| 1830 |
|
or: |
| 1831 |
|
|
| 1832 |
|
<pre> |
| 1842 |
|
[spacing] |
| 1843 |
|
</pre> |
| 1844 |
|
|
| 1845 |
+ |
<p> |
| 1846 |
+ |
|
| 1847 |
|
</dl> |
| 1848 |
|
|
| 1849 |
|
<p> |
| 1888 |
|
cfunc(x) : 10*x / sqrt(x) ; |
| 1889 |
|
</pre> |
| 1890 |
|
|
| 1891 |
+ |
<p> |
| 1892 |
+ |
|
| 1893 |
|
Many variables and functions are already defined by the program, and they are listed in the file rayinit.cal. |
| 1894 |
|
The following variables are particularly important: |
| 1895 |
|
|
| 1904 |
|
arg(i) - i'th real argument |
| 1905 |
|
</pre> |
| 1906 |
|
|
| 1907 |
+ |
<p> |
| 1908 |
+ |
|
| 1909 |
|
For mesh objects, the local surface coordinates are available: |
| 1910 |
|
|
| 1911 |
|
<pre> |
| 1912 |
|
Lu, Lv - local (u,v) coordinates |
| 1913 |
|
</pre> |
| 1914 |
|
|
| 1915 |
+ |
<p> |
| 1916 |
+ |
|
| 1917 |
|
For BRDF types, the following variables are defined as well: |
| 1918 |
|
|
| 1919 |
|
<pre> |
| 1922 |
|
CrP, CgP, CbP - perturbed material color |
| 1923 |
|
</pre> |
| 1924 |
|
|
| 1925 |
+ |
<p> |
| 1926 |
+ |
|
| 1927 |
|
A unique context is set up for each file so |
| 1928 |
|
that the same variable may appear in different |
| 1929 |
|
function files without conflict. |
| 1978 |
|
DATA, later dimensions changing faster. |
| 1979 |
|
</pre> |
| 1980 |
|
|
| 1981 |
+ |
<p> |
| 1982 |
+ |
|
| 1983 |
|
N is the number of dimensions. |
| 1984 |
|
For each dimension, the beginning and ending coordinate values and the dimension size is given. |
| 1985 |
|
Alternatively, individual coordinate values can be given when the points are not evenly spaced. |
| 2008 |
|
... |
| 2009 |
|
</pre> |
| 2010 |
|
|
| 2011 |
+ |
<p> |
| 2012 |
+ |
|
| 2013 |
|
The ASCII codes can appear in any order. N is the number of vertices, and the last is automatically connected to the first. |
| 2014 |
|
Separate polygonal sections are joined by coincident sides. |
| 2015 |
|
The character coordinate system is a square with lower left corner at (0,0), lower right at (255,0) and upper right at (255,255). |
| 2148 |
|
</h2> |
| 2149 |
|
|
| 2150 |
|
<pre> |
| 2151 |
< |
The Radiance Software License, Version 1.0 |
| 2151 |
> |
The Radiance Software License, Version 2.0 |
| 2152 |
|
|
| 2153 |
< |
Copyright (c) 1990 - 2021 The Regents of the University of California, |
| 2154 |
< |
through Lawrence Berkeley National Laboratory. All rights reserved. |
| 2153 |
> |
Radiance v6.0 Copyright (c) 1990 to 2025, The Regents of the University of |
| 2154 |
> |
California, through Lawrence Berkeley National Laboratory (subject to receipt |
| 2155 |
> |
of any required approvals from the U.S. Dept. of Energy). All rights reserved. |
| 2156 |
|
|
| 2157 |
|
Redistribution and use in source and binary forms, with or without |
| 2158 |
< |
modification, are permitted provided that the following conditions |
| 2085 |
< |
are met: |
| 2158 |
> |
modification, are permitted provided that the following conditions are met: |
| 2159 |
|
|
| 2160 |
< |
1. Redistributions of source code must retain the above copyright |
| 2161 |
< |
notice, this list of conditions and the following disclaimer. |
| 2160 |
> |
(1) Redistributions of source code must retain the above copyright notice, |
| 2161 |
> |
this list of conditions and the following disclaimer. |
| 2162 |
|
|
| 2163 |
< |
2. Redistributions in binary form must reproduce the above copyright |
| 2164 |
< |
notice, this list of conditions and the following disclaimer in |
| 2165 |
< |
the documentation and/or other materials provided with the |
| 2093 |
< |
distribution. |
| 2163 |
> |
(2) Redistributions in binary form must reproduce the above copyright |
| 2164 |
> |
notice, this list of conditions and the following disclaimer in the |
| 2165 |
> |
documentation and/or other materials provided with the distribution. |
| 2166 |
|
|
| 2167 |
< |
3. The end-user documentation included with the redistribution, |
| 2168 |
< |
if any, must include the following acknowledgment: |
| 2169 |
< |
"This product includes Radiance software |
| 2170 |
< |
(<a HREF="http://radsite.lbl.gov/">http://radsite.lbl.gov/</a>) |
| 2099 |
< |
developed by the Lawrence Berkeley National Laboratory |
| 2100 |
< |
(<a HREF="http://www.lbl.gov/">http://www.lbl.gov/</a>)." |
| 2101 |
< |
Alternately, this acknowledgment may appear in the software itself, |
| 2102 |
< |
if and wherever such third-party acknowledgments normally appear. |
| 2167 |
> |
(3) Neither the name of the University of California, Lawrence Berkeley |
| 2168 |
> |
National Laboratory, U.S. Dept. of Energy nor the names of its contributors |
| 2169 |
> |
may be used to endorse or promote products derived from this software |
| 2170 |
> |
without specific prior written permission. |
| 2171 |
|
|
| 2172 |
< |
4. The names "Radiance," "Lawrence Berkeley National Laboratory" |
| 2173 |
< |
and "The Regents of the University of California" must |
| 2174 |
< |
not be used to endorse or promote products derived from this |
| 2175 |
< |
software without prior written permission. For written |
| 2176 |
< |
permission, please contact [email protected]. |
| 2172 |
> |
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| 2173 |
> |
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 2174 |
> |
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 2175 |
> |
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| 2176 |
> |
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 2177 |
> |
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 2178 |
> |
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 2179 |
> |
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 2180 |
> |
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 2181 |
> |
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 2182 |
> |
POSSIBILITY OF SUCH DAMAGE. |
| 2183 |
|
|
| 2184 |
< |
5. Products derived from this software may not be called "Radiance", |
| 2185 |
< |
nor may "Radiance" appear in their name, without prior written |
| 2186 |
< |
permission of Lawrence Berkeley National Laboratory. |
| 2187 |
< |
|
| 2188 |
< |
THIS SOFTWARE IS PROVIDED ``AS IS" AND ANY EXPRESSED OR IMPLIED |
| 2189 |
< |
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 2190 |
< |
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| 2191 |
< |
DISCLAIMED. IN NO EVENT SHALL Lawrence Berkeley National Laboratory OR |
| 2192 |
< |
ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 2193 |
< |
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 2120 |
< |
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| 2121 |
< |
USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| 2122 |
< |
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 2123 |
< |
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 2124 |
< |
OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 2125 |
< |
SUCH DAMAGE. |
| 2184 |
> |
You are under no obligation whatsoever to provide any bug fixes, patches, |
| 2185 |
> |
or upgrades to the features, functionality or performance of the source |
| 2186 |
> |
code ("Enhancements") to anyone; however, if you choose to make your |
| 2187 |
> |
Enhancements available either publicly, or directly to Lawrence Berkeley |
| 2188 |
> |
National Laboratory, without imposing a separate written license agreement |
| 2189 |
> |
for such Enhancements, then you hereby grant the following license: a |
| 2190 |
> |
non-exclusive, royalty-free perpetual license to install, use, modify, |
| 2191 |
> |
prepare derivative works, incorporate into other computer software, |
| 2192 |
> |
distribute, and sublicense such enhancements or derivative works thereof, |
| 2193 |
> |
in binary and source code form. |
| 2194 |
|
</pre> |
| 2195 |
+ |
|
| 2196 |
+ |
<p> |
| 2197 |
|
|
| 2198 |
|
<hr> |
| 2199 |
|
|
