Octane Universal Material

Last modified: 10 March 2025
Universal_Material_Node.png

The Universal material integrates more closely with PBR (Physically Based Rendering) workflows such as Substance Designer.

Where the Diffuse, Specular, Glossy, and Metallic materials isolate parameters to design specific material types, the Universal material can design material characteristics associated with any of the other Octane material types.

Node Inputs/Outputs

Parameters

Transmission - Controls how light passes through a transparent surface. It is closely tied with the Dielectric IOR to control the surface's transparency. It accepts a color, texture, or value as an input. However, a color input provides the most control. To create colored glass, change the color input to something other than black and set the Albedo to black. Transmission is different from Opacity. Opacity controls the surface visibility, while Transmission controls the transparency. Use Transmission to create a reflective glass surface, and use Opacity to create a hole in the surface.

Albedo - The material's base color which controls the overall color of a non-metallic opaque material. It can also color a metallic material which is using the Artistic IOR type.

Metallic - Determines how metallic a surface looks. Lower values make the surface look more dielectric, and higher values make the surface look more metallic.

Metallic Edge Tint - The color of the edges of the metal material, only used with Artistic and IOR+Color modes.

Specular - Determines the color of glossy reflections for Dielectric materials (when the Metallic parameter is set to 0). Set the Dielectric IOR parameter higher than 1.0 for the Specular parameter to contribute to the surface characteristics.

Roughness - Determines how much the Specular and Transmission characteristics spread across the surface.

Anisotropy - Determines the shape of Specular and Transmission highlights. A value of -1 creates a horizontal shape, and a value of 1 creates a vertical shape.

Rotation - Controls the Anisotropy shape's rotation.

Spread - Controls the spread of the tail of the specular BSDF (STD only).

Dielectric IOR - This IOR controls the Specular Reflection or Transmission Fresnel effect. By default, if the Dielectric 1/IOR parameter is empty, then the dielectric specular uses this parameter instead.

Dielectric Map (1/IOR) - This parameter overrides the Dielectric IOR when you apply a map or value. This parameter is an Index Of Refraction map, where each texel represents 1/IOR.

Metallic Reflection Mode - This attribute, along with the IOR attributes, provides options for controlling the Index of Refraction across a surface.

Metallic IOR - Complex-valued Index Of Refraction (n-k*i), which controls the Fresnel effect of Metallic materials' specular reflections. For RGB IOR mode, this serves as the Index Of Refraction for the red light (650nm).

Metallic IOR (Green) - For RGB IOR mode, this is the Index Of Refraction for the green light (550nm).

Metallic IOR (Blue) - For RGB IOR mode, this is the Index Of Refraction for the blue light (450nm).

Coating - Provides a second layer of reflection to the surface.

Coating Roughness - Determines how much the Coating characteristic spreads across the surface.

Coating IOR - Controls the Fresnel effect for the surface's Coating characteristics.

Coating Bump - Much like a regular Bump map, this creates fine details on the material's Coating attribute using a Procedural or Image texture.

Coating Normal - This attribute also creates fine details on the surface's coating. A Normal map is a special type of image texture that uses red, green, and blue color values to perturb the normals of the surface at render time, giving the appearance of added detail. They can be more accurate than Bump maps, but require specific software, such as ZBrush®, Mudbox®, Substance Designer, XnormalTM, or others to generate.

Film Width - Simulates the look of thin film material on a surface, like creating a rainbow color effect that appears on an oil slick's surface. Larger values increase the effect's strength.

Film IOR - Controls the film's IOR by adjusting its visible colors.

Sheen - Provides a second layer of glossiness to the surface.

Sheen Roughness - Determines how much the sheen characteristic spreads across the surface.

Sheen Bump - The sheen layer's Bump map. If you don't specify a Bump map, the sheen layer uses the default shading normal. Otherwise, it applies the bump-mapped surface to the sheen layer.

Sheen Normal - The sheen layer's Normal map. If you don't specify a Normal map, the sheen layer uses the default shading normal. Otherwise, it applies the normal-mapped surface to the sheen layer.

Disp(ersion) Coefficient - This is the B parameter of the Cauchy dispersion model, where normal dispersion is derived through the relationship between the Index Of Refraction and the wavelength of light passing through transparent materials. Increasing the Dispersion value increases the amount of coloration and dispersion in the object's transmission and in caustics.

Medium - OctaneRender® has three types of mediums to create translucent surfaces: Absorption, Scattering, and Volume. To use these options, connect the Diffuse material's Medium input to either the Absorption or Scattering medium nodes.

  • Absorption Medium - Produces the appearance of a material that absorbs light while passing through a surface. The color resulting from this absorption depends on the distance light travels through the material. The Absorption map type is covered in more detail under the Mediums category.

  • Scattering Medium - Similar to the Absorption medium, but with an additional option to simulate subsurface scattering. Subsurface scattering is the phenomenon that gives human skin, and similar organic surfaces, their characteristic glow under certain lighting conditions. It is a major component in creating the look of realistic skin. The Scattering map type is covered in more detail under the Mediums category.

  • Volume Medium - Creates the effect of volumetric surfaces when applied to VDB files imported into Unreal® using openVDB.

  • Random Walk - A newer variant of subsurface scattering that utilizes a stochastic or random process for the scattering of light through an object.

  • Standard Volume Medium - A volume medium node with comprehensive controls for adjusting volume, scatter, transparency, emission, and temperature parameters based on imported VBD grid data.

Opacity - Determines what surface parts are visible in the render. Dark values indicate transparent areas, and light values indicate opaque areas. Values between light and dark indicate semi-transparent areas. Lowering the Opacity value fades the object's overall visibility, or you can use a Texture map to vary the surface's opacity. For example, if you want to make a simple polygon plane look like a leaf, you connect a black-and-white image of the leaf's silhouette to the Diffuse shader's Opacity channel. When you use an Image texture map, set the Data type to Alpha Image if the image has an Alpha Channel, or Grayscale image for black-and-white images, to load an image for setting transparency. Use the image's Invert checkbox to invert the transparency regions.

Bump - Creates fine details on material surfaces using a Procedural or Image texture. When you connect a Grayscale image texture to this parameter, light areas appear as protruding bumps, and dark areas appear as indentations. You can adjust the Bump map strength by setting the Power or Gamma values on the Grayscale image texture node. These attributes are covered in more detail under the Octane Textures section of this manual.

Bump Height - Determines the height of the bump map.

Normal - Creates fine details on the surface. A Normal map is a special type of Image texture that uses red, green, and blue color values to perturb the surface normals at render time, giving the appearance of added detail. They can be more accurate than Bump maps, but require specific software, such as ZBrush®, Mudbox®, Substance Designer, xNormalTM, or others to generate. To load a full-color Normal map, set the Normal channel to the RGB Image data type. Note that Normal maps take precedence over Bump maps, so you cannot use a Normal map and a Bump map at the same time.

Displacement - Adjusts the surface vertices' height at render time using a Texture map. Displacement maps differs from Bump or Normal maps in that the geometry is altered by the texture, as opposed to just creating the appearance of detail. Displacement mapping is more complex than using a Bump or Normal map, but the results are more realistic, especially along the silhouette of the surface. Displacement mapping is covered in more detail under the Octane Textures section of this manual.

Round Edges - Uses the Octane Render Round Edges node as an input to provide the following options:

  • Mode - The Fast mode uses the rounding method introduced in OctaneRender® v3. The Accurate mode produces better-looking results, but may be slower. Accurate mode can select the affected edges by using the Concave Only or Convex Only options.

  • Radius - The rounded edge's radius.

  • Roundness - Controls the rounded edge's shape. A value of 1 is completely round, while 0 is a chamfer.

  • Samples - The number of rays to use when sampling neighboring geometry.

  • Consider Other Objects - Controls how rounded edges are applied to different objects. When enabled, intersections between different objects are rounded. When disabled, only the current object is considered.

Emission - Create a surface that emits light (also known as a Mesh emitter). To use this option, connect the Diffuse material's Emission input to either a Blackbody or Texture emission node. These nodes are covered in more detail under the Mesh Emitters topic under the Lighting category of this manual.

Material Layer - Connects any of the Octane Material layers, which provide greater flexibility for mixing and blending multiple surface characteristics.

LightWave Material - Connects any of the LightWave Material layers, which provide greater flexibility for mixing and blending multiple surface characteristics.

Node Attributes

Octane Render Attributes Tab - Main

  • Transmission Type - Determines how light refracts. There are four (4) Transmission types which are described as follows:

    • Specular - Can be used for glass, liquids, and glossy minerals like gemstones. Use the Dielectric IOR channel to control how light bends through this type of material. This mode works well with the Absorption medium to create realistic liquids, or the Scattering/Random Walk medium to create minerals or cloudy liquids.

    • Diffuse - Can be used for semi-transparent solids. When combined with a Scattering or Random Walk medium, it is ideal for skin, plastics and other non-glossy semi-transparent materials.

    • Thin Wall - Can be used for surfaces like soap bubbles or very thin plastics and glass. By itself it's difficult to see this effect, so it needs either some contribution from the Specular channel or a Coating Layer to really stand out.

    • Thin Wall (Diffuse) - Can be used for leaves, lampshades, and other very thin objects that still have a strong subsurface scattering effect.

  • Albedo - The material's base color which controls the overall color of a non-metallic opaque material. It can also color a metallic material which is using the Artistic IOR type.

  • 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 effects each BRDF, which describes the surface's microscopic shape (i.e. micro-facet normals) and scales the brightness of the BRDF's reflections.