Subsurface scattering

Intermediate Artist

When you enable subsurface scattering on a material, light is reflected at irregular angles inside the model. You can use this to realistically render translucent materials such as skin, wax, leaves, marble, and porcelain.

The photo below demonstrates a real-life example of the effect:

Photo

(Image courtesy of Davepoo2014, shared under Creative Commons Attribution-Share Alike 4.0 International license)

The screenshots below demonstrate the use of subsurface scattering in Stride to render wax:

Subsurface scattering off Subsurface scattering on
On Off

The shadows are much softer in the second image, as more light passes through the candles.

Enable subsurface scattering

  1. Select the material you want to use subsurface shading.

  2. In the Property Grid, under Shading, next to Subsurface scattering, click Blue arrow button (Replace) and choose Subsurface scattering.

    Enable subsurface scattering

Properties

Properties

Property Function
Scattering width How far the light scatters in world units
Translucency How much light pentrates the material. 0.0 is no translucency; 1.0 is max.
Translucency map Specify a grayscale map to control how translucent different regions of the material are. Brighter values produce more scattering. For example, ears should scatter more light than the top of the head, because they're thinner and therefore light passes through them more easily. The texture is multiplied by the Translucency parameter.
Scattering profile The scattering profile to use during the forward render pass.


Skin: A preconfigured shader for rendering skin


Custom (skin-based): A profile based on the Skin profile you can customize yourself
Scattering kernel The scattering kernel to use in the subsurface scattering post process.


Falloff: Scattered light is masked to this color. For example, in the screenshot of the candles, the light fades to an orange-yellow.


Strength: Fades to this color
Transluency: 0.2 Transluency: 0.98
On Off

Graphics compositor options

There are additional subsurface scattering options in the graphics compositor editor. These options apply globally to all materials that use subsurface scattering.

  1. In the Asset View (in the bottom pane by default), double-click the Graphics Compositor asset.

    Graphics compositor asset

    The graphics compositor editor opens.

  2. Select the Subsurface scattering node.

    Select node

  3. In the Property Grid (on the right by default), edit the properties.

    Subsurface scattering blur

Properties

Property Function
Follow surface Prevent light scattering across large depth differences. Affects GPU performance.
Passes The number of times the blur is executed. More passes produce smoother results (less noise and banding).
Jitter kernel size Use noise to reduce banding artifacts caused by undersampling. Creates a smoother effect, but is technically less accurate (sometimes noticeable at close distances).
Render mode Change the render mode for debugging purposes

See also