Arnold Standard Surface

Note:  The non-active inputs (highlighted in gray) help drive the shaders but have no effects on the canvas. This page is based on the Arnold Standard Surface shader documentation, for more information, see https://docs.arnoldrenderer.com/display/A5AFMUG/Standard+Surface.

Control

Type

What it does

Notes

toggle

Toggles the influence of channels connected to the shader without disconnecting them from the shader input.

Displacement Map is toggled off by default.

Inputs | Diffuse Weight

dropdown

The channel controlling the diffuse weight effect of the shaded surface.

Default is 0.8

Inputs | Diffuse Color

dropdown

The channel controlling the diffuse color effect of the shaded surface.

 

Inputs | Diffuse Roughness

dropdown

The channel controlling the diffuse roughness effect of the shaded surface.

 

Inputs | Metalness

dropdown

The channel controlling the metalness effect of the shaded surface.

 

Inputs | Specular Weight

dropdown

The channel controlling the specular weight effect of the shaded surface.

 

Inputs | Specular Color

dropdown

The channel controlling the specular color effect of the shaded surface.

 

Inputs | Specular Roughness

dropdown

The channel controlling the specular roughness effect of the shaded surface.

 

Inputs | Specular IOR

dropdown

The channel controlling the specular IOR effect of the shaded surface.

 

Inputs | Anisotropy

dropdown

The channel controlling the anisotropy effect of the shaded surface.

 

Inputs | Anisotropy Rotation

dropdown

The channel controlling the anisotropy rotation effect of the shaded surface.

 

Inputs | Transmission Weight

dropdown

The channel controlling the transmission weight effect of the shaded surface.

 

Inputs | Transmission Color

dropdown

The channel controlling the transmission color effect of the shaded surface.

 

Inputs | Transmission Depth

dropdown

 

 

Inputs | Transmission Scatter

dropdown

 

 

Inputs | Transmission Scatter Anisotropy

dropdown

 

 

Inputs | Transmission Dispersion

dropdown

 

 

Inputs | Transmission Extra Roughness

dropdown

 

 

Inputs | Subsurface Weight

dropdown

The channel controlling the subsurface weight effect of the shaded surface.

 

Inputs | Subsurface Color

dropdown

The channel controlling the subsurface color effect of the shaded surface.

 

Inputs | Subsurface Radius

dropdown

The channel controlling the subsurface radius effect of the shaded surface.

 

Inputs | Subsurface Scale

dropdown

The channel controlling the subsurface scale effect of the shaded surface.

 

Inputs | Clearcoat Weight

dropdown

The channel controlling the clearcoat weight effect of the shaded surface.

 

Inputs | Clearcoat Color

dropdown

The channel controlling the clearcoat color effect of the shaded surface.

 

Inputs | Clearcoat Roughness

dropdown

The channel controlling the clearcoat roughness effect of the shaded surface.

 

Inputs | Clearcoat IOR

dropdown

The channel controlling the clearcoat IOR effect of the shaded surface.

 

Inputs | Sheen Weight

dropdown

 

 

Inputs | Sheen Color

dropdown

 

 

Inputs | Sheen Roughness

dropdown

 

 

Inputs | Thin Film Thickness

dropdown

 

 

Inputs | Thin Film IOR

dropdown

 

 

Inputs | Emission Weight

dropdown

The channel controlling the emission weight effect of the shaded surface.

 

Inputs | Emission Color

dropdown

The channel controlling the emission color of the shaded surface.

 

Inputs | Opacity

dropdown

The channel controlling the opacity effect of the shaded surface.

 

Inputs | Normal Map

dropdown

The channel controlling the normal map effect of the shaded surface.

 

Inputs | Bump Map

dropdown

The channel controlling the bump map effect of the shaded surface.

 

Inputs | Vector Map

dropdown

The channel controlling the vector map effect of the shaded surface.

 

Inputs | Displacement Map

dropdown

The channel controlling the displacement map effect of the shaded surface.

Displacement Map is toggled off by default.

button

Adds a new channel for the shader component.

Add Channel Dialog

Base

Control

Type

What it does

Weight

text field, slider

The base color weight.

Color

swatch, / Color/Scalar icon

The base color sets how bright the surface is when lit directly with a white light source (intensity at 100%). It defines which percentage for each component of the RGB spectrum that does not get absorbed when light scatters beneath the surface. Metal normally has a black or very dark base color, however, rusty metals need some base color. A base color map is usually required.

Roughness

text field, slider

The base component follows an Oren-Nayar reflection model with surface roughness. A value of 0.0 is comparable to a Lambert reflection. Higher values will result in a rougher surface look more suitable for materials like concrete, plaster, or sand.

Metalness

text field, slider

With metalness 1.0 the surface behaves like a metal, using fully specular reflection and complex Fresnel.

Specular

Control

Type

What it does

Weight

text field, slider

The specular weight influences the brightness of the specular highlight.

Color

swatch, / Color/Scalar icon

The color the specular reflection is modulated with. Use this color to 'tint' the specular highlight. You should only use colored specular for certain metals, whereas non-metallic surfaces usually have a monochromatic specular color. Non-metallic surfaces normally do not have a colored specular.

Roughness

text field, slider

Controls the glossiness of the specular reflections. The lower the value, the sharper the reflection. A value of 0 gives you a perfectly sharp mirror reflection, while 1.0 creates reflections that are close to a diffuse reflection. You should connect a map here to get variation in the specular highlight.

IOR

text field

The IOR parameter (Index of Refraction) defines the material's Fresnel reflectivity and is by default the angular function used. Effectively the IOR defines the balance between reflections on surfaces facing the viewer and on surface edges. You can see the reflection intensity remains unchanged, but the reflection intensity on the front side changes a lot.

Anisotropy

text field, slider

Anisotropy reflects and transmits light with a directional bias and causes materials to appear rougher or glossier in certain directions. The default value for Anisotropy is 0, which means 'isotropic.' As you move the control towards 1.0, the surface is made more anisotropic in the U axis.

Anisotropy Rotation

text field, slider

The rotation value changes the orientation of the anisotropic reflectance in UV space. At 0.0, there is no rotation, while at 1.0 the effect is rotated by 180 degrees. For a surface with brushed metal, this controls the angle at which the material was brushed. For metallic surfaces, the anisotropic highlight should stretch out in a direction perpendicular to the brushing direction.

Transmission

Control

Type

What it does

Weight

text field, slider

Allows light to scatter through the surface, for materials such as glass or water.

Color

swatch, / Color/Scalar icon

This filters the refraction according to the distance traveled by the refracted ray. The longer light travels inside a mesh, the more it is affected by the Transmission Color. Therefore green glass gets a deeper green as rays travel through thicker parts. The effect is exponential and computed with Beer's Law. It is recommended to use light, subtle color values.

Depth

text field

Controls the depth into the volume at which the transmission color is realized. Increasing this value makes the volume thinner, which means less absorption and scattering. It is a scale factor so that you can set a transmission color and then tweak the Depth to be appropriate for the size of your object.

Scatter

swatch, / Color/Scalar icon

Transmission Scatter is suitable for any liquid that is fairly thick or where there is enough of it for scattering to be visible, such as a deep body of water or honey. If you have a glass of water, there is not that much scattering, however, for an ocean, it is required. Other examples include materials like ice, opalescent glass or milky glass.

Scatter Anisotropy

text field, slider

The directional bias, or anisotropy, of the scattering. The default value of zero gives isotropic scattering so that light is scattered evenly in all directions. Positive values bias the scattering effect forwards, in the direction of the light, while negative values bias the scattering backward, toward the light.

Dispersion

text field, slider

Specifies the Abbe number of the material, which describes how much the index of refraction varies across wavelengths. For glass and diamonds, this is typically in the range of 10 to 70, with lower numbers giving more dispersion. The default value is 0, which turns off dispersion.

Extra Roughness

text field, slider

Adds some additional blurriness of a refraction computed with an isotropic microfacet BTDF (Bidrectional Transmittance Distribution Function). The range goes from 0 (no roughness) to 1.

Subsurface

Control

Type

What it does

Weight

text field, slider

The 'blend' between diffuse and subsurface scattering. When set to 1.0, there is only SSS, and when set to 0 it is only Lambert. In most cases, you want this to be 1.0 (full SSS).

Color

swatch, / Color/Scalar icon

The color used to determine the subsurface scattering effect. For example, replicating a skin material would mean setting this to a fleshy color.

Radius

swatch, / Color/Scalar icon

The approximate distance up to which light can scatter below the surface, also known as “mean free path” (MFP). This parameter affects the average distance that light might propagate below the surface before scattering back out. This effect on the distance can be specified for each color component separately. Higher values smooth the appearance of the subsurface scattering, while lower values result in a more opaque look.

Scale

text field

Controls the distance that the light is likely to travel under the surface before reflecting back out. It scales the scattering Radius and multiplies the SSS Radius Color.

Clearcoat

Control

Type

What it does

Weight

text field, slider

This attribute is used to coat the material. It acts as a clear-coat layer on top of all other shading effects. The coating is always reflective (with the given roughness) and is assumed to be dielectric, such as the clear-coat layer for car paint or the sheen layer for a skin material. For example, for an extra oily layer or wet skin. Other examples include objects that have been laminated or a protective film over an aluminum cell phone.

Color

swatch, / Color/Scalar icon

This is the color of the coating layer's transparency.

Roughness

text field, slider

Controls the glossiness of the specular reflections. The lower the value, the sharper the reflection. In the limit, a value of 0 gives you a perfectly sharp mirror reflection, while 1.0 creates reflections that are close to a diffuse reflection. You should connect a map here to get variation in the coat highlight.

IOR

text field

The IOR parameter (Index of Refraction) defines the material's Fresnel reflectivity and is by default the angular function used. Effectively the IOR defines the balance between reflections on surfaces facing the viewer and on surface edges. You can see the reflection intensity remains unchanged, but the reflection intensity on the front side changes a lot.

Sheen

Control Type

Weight

text field, slider

Color

swatch, / Color/Scalar icon

Roughness

text field, slider

Thin Film

Control Type

Thickness

text field, slider

IOR

text field

Emission

Control

Type

What it does

Weight

text field, slider

Controls the amount of emitted light. It can create noise, especially if the source of indirect illumination is very small (for example, light bulb geometry).

Color

swatch, / Color/Scalar icon

The emitted light color.

Geometry

Control

Type

What it does

Thin Walled

checkbox

When enabled, provides the effect of a translucent object being lit from behind (the shading point is 'lit' by the specified fraction of the light hitting the reverse of the object at that point). It is recommended that this only be used with thin objects (single sided geometry) as objects with thickness may render incorrectly.

Opacity

swatch, / Color/Scalar icon

Controls the transparency of the surface, white is fully opaque and black is fully transparent.

Advanced

Control

Type

What it does

Caustics

checkbox

 

Internal Reflections

checkbox

 

Exit to Background

checkbox

When enabled, this causes the Standard Surface shader to trace a ray against the background/environment when the maximum GI reflection/refraction depth is met and return the color that is visible in the background/environment in that direction. When the option is disabled, the path is terminated instead and returns black when the maximum depth is reached.

Indirect Diffuse Weight

text field, slider

 

Indirect Specular Weight

text field, slider

 

Displacement

Control

Type

What it does

Notes

Displacement

Displacement Bias

text field, slider

How much the white or black values are pushed or pulled from the surface.

Ranges from 0 to 1; defaults to 0.500.

Displacement Scale

text field, slider

How much displacement is applied to the shaded surface. Lower values equal smaller displacement; higher values equal larger and more obvious displacement.

Ranges from 0 to 1; defaults to 0.500.

Displacement Range

text field

What the range of displacement is. This setting is multiplied by the Displacement Scale to give the displacement.

 

Max Tesselation

text field, slider

How many texels the surface is tessellated to.

Ranges from 1 to 64; defaults to 10.

Perturb Normals

dropdown

Selecting Yes changes the displacement so that it moves the surface but leaves the surface normals as they are.

 

Bump

Control

Type

What it does

Notes

Bump

Bump Weight

text field, slider

How much weight the bump map has. Lower values are smaller bumps, higher values are larger and more obvious displacements.

Ranges from 0 to 10; defaults to 1.000.

Bump Mode

dropdown

Displays bump quickly (Fast), accurately (Accurate), or less accurately (Fastest).

While Fastest is very fast, it works better with live procedural layers rather than painted or cached layers.

Bump Space

dropdown

UV - Normals are calculated relative to the UV coordinates space.
The UV Bump Space mode is the more traditional approach but can lead to noticeable seams and color variations.

World - Normals are calculated relative to the World coordinates space.
Using the World Bump Space mode gives a more seamless result.

By default, Bump Space is set to UV.