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.\" RCSid "$Id$" |
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.\" Print using the -ms macro package |
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< |
.DA 07/10/2016 |
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.DA 5/11/2023 |
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.LP |
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< |
.tl """Copyright \(co 2016 Regents, University of California |
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.tl """Copyright \(co 2023 Regents, University of California |
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.sp 2 |
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.TL |
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The |
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Also, rather than roughness, specular power is used, which has no |
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physical meaning other than larger numbers are equivalent to a smoother |
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surface. |
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Unlike other material types, total reflectance is the sum of |
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diffuse and specular colors, and should be adjusted accordingly. |
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.DS |
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mod ashik2 id |
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4+ ux uy uz funcfile transform |
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Unlike other data-driven material types, the BSDF type is fully |
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supported and all parts of the distribution are properly sampled. |
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.LP |
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.UL aBSDF |
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.PP |
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The aBSDF material is identical to the BSDF type with two important |
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differences. |
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First, proxy geometry is not supported, so there is no thickness parameter. |
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Second, an aBSDF is assumed to have some specular through component |
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(the 'a' stands for "aperture"), which |
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is treated specially during the direct calculation and when viewing the |
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material. |
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Based on the BSDF data, the coefficient of specular transmission is |
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determined and used for modifying unscattered shadow and view rays. |
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.DS |
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mod aBSDF id |
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5+ BSDFfile ux uy uz funcfile transform |
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0 |
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0|3|6|9 |
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rfdif gfdif bfdif |
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rbdif gbdif bbdif |
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rtdif gtdif btdif |
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.DE |
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.LP |
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If a material has no specular transmitted component, it is much better |
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to use the BSDF type with a zero thickness than to use aBSDF. |
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.LP |
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.UL Antimatter |
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.PP |
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Antimatter is a material that can "subtract" volumes from other volumes. |
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in Lausanne, Switzerland. |
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.NH 1 |
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References |
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.LP |
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Wang, Taoning, Gregory Ward, Eleanor Lee, |
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``Efficient modeling of optically-complex, non-coplanar |
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exterior shading: Validation of matrix algebraic methods,'' |
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.I "Energy & Buildings", |
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vol. 174, pp. 464-83, Sept. 2018. |
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.LP |
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Lee, Eleanor S., David Geisler-Moroder, Gregory Ward, |
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``Modeling the direct sun component in buildings using matrix |
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algebraic approaches: Methods and validation,'' |
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.I Solar Energy, |
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vol. 160, 15 January 2018, pp 380-395. |
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.LP |
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Ward, G., M. Kurt & N. Bonneel, |
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``Reducing Anisotropic BSDF Measurement to Common Practice,'' |
