Skin material

This is a simple inexpensive skin material for use on non-hero models.

This skin material adds a subsurface scattering color to the diffuse color. The base color has a hue shift function and a crackle pattern to add details to the surface. A sheen specular calculation is added to the standard specular choices. There is no displacement currently used in this material, but the crackle pattern could be used in a displacement shader and the result of the displacement imported into the surface shader, if desired.

Parameters

Surface

Lambert Intensity	A multiplier for the diffuse contribution to the material.
Skin Color	This is the base skin color for the material.
Opacity	The opacity color for this material.
Use Point Alpha	If set, the Alpha attributes will be multiplied into the final Opacity. If no Alpha Attribute exists, Opacity is unaffected.

Crackle

Crackle Color	This is the crackle pattern color which is blended with skin color. This is used as a substitute for a displacement shader. The result of the displacement shader could be imported into the surface for the blend, if desired.
Crack Frequency	The frequency of the crackle pattern. Higher value result in a finer grain. This value is doubled for the secondary cell noise.
Crack Width	The width of the crackle lines. Default is 0.1.
Crack Softness	The softness of the crackle lines. Default is 0.2.
Secondary Contribution	This controls the contribution of the secondary cracks. When this value is one the secondary cracks are as prevalent as the main cracks. At zero the secondary cracks are not visible. Default is 0.2.

Hue Shift

Hue Shift Amplitude	This value controls the amount along the color wheel to shift the input color. It should be a float between -0.5 and 0.5. Zero is no change.
Hue Shift Map	This map controls the distance and direction along the color wheel to shift the base color. 50% gray is no change. Black shifts the color to the left the total value of the Amplitude, while white shifts the color to the left the total value of the Amplitude.
Hue Shift Map Wrap	Determines what the texture looks like when the texture coordinates are larger or less than 0 to 1. See texture for more information. Repeat means the texture will repeat (tile). Streak means the texture color at the edges is clamped and streaks outside the map. Decal sets the color outside the texture map to the Border Color.
Hue Shift Filter	Type of anti-aliasing filter used. See texture for more information.
Hue Shift Filter Width	Filter Width is the number of pixels, in both u and v directions, to use in filtering. See texture for more information.
Hue Shift Border	The color used outside the map if Decal Wrap is selected. See texture for more information.

Subsurface Scattering

Subsurface Intensity	A multiplier for the subsurface scattering contribution to the material. This is independent of the subsurface scattering calculation.
Subsurface Color	This color is used to tint the color returned from the subsurface scatter calculation. Defaults to a deep red. A texture map could be used for this color.
SSS Index of Refraction	This is the amount the incident ray, I, bends as it pass through the surface. Values greater than the default, 0.5, "push" the subsurface scatter more towards the edges. However lower values may "wrap" the contribution too far around the front of the surface. The Subsurface Intensity should be adjusted in conjunction with the Index of Refraction. It is supposed to be subtle.
Depth	This value is used specify how far the incident ray, I, travels after it hits the surface, before it “bounces”. This values should be related to the thickness of the surface being shaded.

Specular

Specular Intensity	A multiplier for the specular contribution to the material.
Specular Color	The specular highlight color, defaults to a very pale pink.
U Roughness	This value controls the size or spread of the specular highlight. If Anisotropic is selected, this value controls the specular highlight in only the U direction.
V Roughness	If Anisotropic is selected, this value controls the specular highlight in only the V direction It is ignored with any other specular function.
Sharpness	This value controls the sharpness of the edge of the specular highlight. It is used only if Glossy specular is selected.
Specular Type	A selector for the specular function. Anisotropic is used to get an elliptical highlight. Glossy is typically used for highly reflective materials to get a sharp edges highlight.

Sheen

Sheen Intensity	A multiplier for the sheen contribution to the material.
Sheen Color	The sheen highlight color, defaults to a soft pink.
Index of Refraction	This value controls how much the sheen adds to the surface. Higher values "push" the sheen more towards the edges. Often it is easier to start with a value of 0.2 and an Intensity of 2 or 3, so the sheen contribution is easier to place and then return to the defaults. It is supposed to be subtle.
Roughness	This value controls the size or spread of the sheen highlight.