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 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 is used for shiny materials like plastics, or clear materials like glass. Material Layers can connect to the Layered Material, Layer Group, Material Layer Switch, or a Material Layer pins on the standard Octane materials (Figure 1).
Figure 1: A Specular layer node connected to the Layer input pin on an Octane Diffuse materialUsed for dull, non-reflecting materials or mesh emitters.
Enabled - Enables or disables this node in a material layer network.
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 - The BRDF (Bidirectional Reflectance Distribution Function) determines the amount of light that a material reflects when light falls on it. For glossy materials, you can choose from six BRDF models. Specific geometric properties (the micro-facet distribution) of the surface affects each BRDF, which describes the surface's microscopic shape (i.e. micro-facet normals) and scales the brightness of the BRDF's reflections (figure 2).
Figure 2: The various BRDF models available for specularity
Roughness - The layer's roughness.
Affect roughness - Override the roughness value of the base material with the Sheen roughness value.
Anisotropy - The layer's anisotropy. A value of -1 is horizontal, while 1 is vertical. A value of 0 is isotropic.
Rotation - The specular anisotropic reflection's rotation.
Spread - Determines the tail spread of the specular BSDF.
IOR - The specular Reflection's or Transmission's Index Of Refraction.
1/IOR Map - The Index of Refraction map. Each texel represents 1/IOR. When this is empty, OctaneRender® uses the IOR value. If this is not empty, then this parameter overrides the Index Of Refraction set by the IOR value.
Allow Caustics - If enabled, the photon tracing kernel will create caustics for light reflecting or transmitting through objects with this material applied.
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 light reflects or goes straight though the layer.
Bump - Simulates a relief by using a Greyscale texture interpreted as a Height map for the Layer.
Bump Height - Determines the strength of the bump map. A value of 0 provides no bump height and negative values will invert the bump map.
Normal - Distorts Layer normals using an RGB image.
Dispersion Coefficient - The B parameter of the Cauchy dispersion model. Increasing this value increases the coloration amount and dispersion in the Layer’s transmission and caustics.
Dispersion Mode - Determines how the IOR and dispersion inputs are interpreted.
Layer Opacity - Controls the Layer's opacity with a Greyscale texture.
Compatibility Mode - The Octane version that the behavior of this node should match. The default is Latest (2023.1). The 2022.1 compatibility mode is the legacy behavior where Bump map strength is active but Bump Map Height is ignored.