Since | 19.0 |
bsdf chiang(vector nn, vector tanV, float R_v, float R_s, float TT_v, float TT_s, float TRT_v, float TRT_s, float shift, vector absorption_coeff, float ior, ...)
Creates a BSDF for computation of the physically based hair model described in paper “A Practical and Controllable Hair and Fur Model for Production Path Tracing” by Chiang et al.
Suitable only for curve geometry.
See writing a PBR shader for information on BSDFs.
nn
bumped/shading normal
tanV
tangent vector along V
R_v
Longitudinal roughness value “v” for lobe R (section 4.1 of the paper)
R_s
Azimuthal roughness value “s” for lobe R (section 4.1 of the paper)
TT_v
Longitudinal roughness value “v” for lobe TT (section 4.1 of the paper)
TT_s
Azimuthal roughness value “s” for lobe TT (section 4.1 of the paper)
TRT_v
Longitudinal roughness value “v” for lobe TRT (section 4.1 of the paper)
TRT_s
Azimuthal roughness value “s” for lobe TRT (section 4.1 of the paper)
shift
Represents the cuticle angle, which affects the position of the specular highlight. Input range of -1 to 1 is internally mapped to -90 to 90 (eg meaning 3-degrees would be 3/90 = 0.03333)
absorption_coeff
The absorption coefficient (section 4.2 of the paper)
ior
Index of refraction (eg 1.55)
See also | |
bsdf |
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pbr |
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shading |
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