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Hair Fiber#


  • Category: /Material/Physical
  • Default object name: hair_fiber

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Physically-based shader for hair and fur fibers.


Name Type Description
Export Aovs bool Compute and write Aovs defined in the shading graph
Arbitrary Output Variables reference (AovStore) Set the list of extra channels to write to the image.
Light Path Expression Label string Set the material label in light path expressions.
Material Sample Count long Material sample count per pixel.
Glossy Reflection Sampling Multiplier double Material glossy reflection sample count multiplier.
Glossy Transmission Sampling Multiplier double Material glossy transmission sample count multiplier.
Russian Roulette double Amount of Russian roulette used on the material samples.
Roughness Noise Optimization double Noise reduction strategy along rough light path.
Glossy Reflection Depth long Maximum glossy reflection depth.
Glossy Transmission Depth long Maximum glossy transmission depth.
Opacity double[3] Opacity of the material.
Normal Mode long Define which geometric normal to use for the shading.
Shadow Casting Mode long Defines the properties of the material when casting shadows: fully opaque (regardless of the actual value of the opacity of the material), artistic (user-defined opacity and coloring), pseudo-caustics (cheaply emulating actual refractive caustics) or physical (intrinsic transparency of the material), where the last three are modulated by the opacity of the material.
Shadow Opacity double Defines how dark the shadows cast by this material are.
Shadow Coloring double Defines how much refraction and absorption colors affect shadowing.
Reflective Caustics long Reflective caustics computation mode.
Refractive Caustics long Refractive caustics computation mode.
Melanin Amount double Concentration of natural melanin pigment: low to high values result in hair color gradually ranging between white, blond, brown/auburn/red (depending on melanin mixture) and black.
Melanin Redness double Relative mixture of pheomelanin (yellow/red pigment) compared to eumelanin (brown/black pigment): at intermediate melanin concentrations, mixtures from 0% to 100% result in hair color gradually ranging between brown, auburn and red.
Dye Mix double Relative blend of artificial dye pigment compared to natural melanin pigment.
Dye Albedo double[3] Custom apparent color of artificial dye pigment (a white pigment does not absorb any light).
Highlight Roughness double Apparent longitudinal roughness along the fibers (between the roots and the tips).
Fiber Softness double Apparent azimuthal roughness across the fibers (within their cross-sections).
Cuticle Tilt double Tilt angle of the cuticle scales: positive values shift the reflection highlight toward the tip and the transmission and scattering highlights toward the root, whereas negative values shift all three highlights in the opposite direction. Set to 0 degrees for synthetic hair without cuticle scales, while typical values for human hair range between 2 and 4 degrees.
Index Of Refraction double Refractive index of the dielectric surface of the fibers: higher values give stronger Fresnel reflections and scattering inside the fibers, whereas lower values give stronger transmission through the fibers (as with wet hair).
Reflection Tint double[3] Color tint of light that is directly reflected off the fibers surface (a.k.a. R lobe).
Transmission Tint double[3] Tint modifying the color of light that is directly transmitted through the interior of the fibers (a.k.a. TT lobe).
Single Scattering Tint double[3] Tint modifying the color of light that bounces once inside the fibers (a.k.a. TRT lobe).
Multiple Scattering Tint double[3] Tint modifying the color of light that bounces multiple times inside the fibers (a.k.a. TRR+T lobe).