SpecularAmount of specular reflection, or the mirror-like reflection of light photons at the same angle. Used for transparent materials such as glass and water. Layer

 

The layered material system lets you construct complex materials that consist of a base layer and up to eight MaterialThe representation of the surface or volume properties of an object. Layers. The layers are based on components used in previous Octane materials. Using this set of unique layers, OctaneRender® now lets you recreate complex materials in a physically-based manner, as opposed to manually mixing materialsUsed to mix any two material types. together.

 

The Specular layer is used for shiny materials like plastics, or clear materials like glass. Refer to the GlossyThe measure of how well light is reflected from a surface in the specular direction, the amount and way in which the light is spread around the specular direction, and the change in specular reflection as the specular angle changes. Used for shiny materials such as plastics or metals., Specular, and Universal Material topics in this manual for more information. Material Layers can connect to the Material Layer, Layer Group, or Layer pin on standard materials (Figure 1).

Specular_Layer_Fig01_Houdini_v2021.JPG

Figure 1: A Specular Layer mode connected to the Layer pin on a DiffuseAmount of diffusion, or the reflection of light photons at different angles from an uneven or granular surface. Used for dull, non-reflecting materials or mesh emitters. Material node

 

Specular Layer Parameters

 

Specular

The layer's coating color.

 

TransmissionA surface characteristic that determines if light may pass through a surface volume.

The layer's transmission color.

 

BRDF Model

Provides three options for determining the overall bidirectional reflectance distribution function (BRDF). The Octane option produces a brushed metal effect. The Beckmann, GGX, and Ward options produce more polished chrome-like effects.

 

Roughness

The layer's roughness.

 

Affect Roughness

The percentage of roughness affecting subsequent layer roughness.

 

Anisotropy

The layer's anisotropy. A value of -1 is horizontal, while 1 is vertical. A value of 0 is Isotropic.

 

Rotation

The rotation of the specular anisotropic reflection.

 

Spread

Determines the tail spread for the specualr BSDF (Bidirectional ScatteringDefines how fast light gets scattered when traveling through the medium. Distribution Function) model of the specular layer.

 

IOR/Index

Controls the Fresnel effect of the reflection and refraction of light when it enters or exits the material. You can find standard values of Index Of Refraction (IOR) by searching the internet. Glass has a value of 1.53, and water has a value of 1.33.

 

Film Width

Sets the film coating's thickness.

 

Film IOR

Sets the film coating's Index Of Refraction.

 

Thin Layer

Makes the layer very thin so it reflects, or goes straight though the layer.

 

Bump

Simulates a relief by using a Greyscale texture interpreted as a Height map for the layer.

 

Normal

Distorts layer normals using an RGB image.

 

Dispersion Coefficient

This is the B parameter of the Cauchy dispersion model. Increasing this value increases the coloration amount and dispersion in the layer’s transmission and caustics.

 

Opacity

Controls the layer's opacity with a Greyscale texture.