lm_sample_shader

Shader Family: Texture

Output: Color

Related mental ray shader: misss_lambert_gamma

This is a Softimage spdl-based version of the mental ray subsurface scattering component shader used in the SSS shader compounds.

The lm_sample_shader acts as the lightmap sampling shader used when creating fast subsurface scattering effects from "scratch". Any illumination shader can be used instead, but this one is specifically tuned for the job and has options for lightmap gamma, normal flipping and indirect light inclusion.

NoteNote that fast subsurface scattering effects are not included in the maps generated by the RenderMap tool.

Ambient	Ambient color contribution.
Diffuse	Diffuse color contribution.
Diffuse Gamma	The gamma curve for diffuse light. The Lambertian cosine is raised to the power of this value to flatten (for values less than 1.0) or narrow (for values above 1.0) the curve for greater control.
Add Indirect Lighting	When enabled, will cause indirect illumination (such as final gathering and photons) to be included in the lightmap, at the expense of increased rendering time.
Normal Direction	Unchanged: Normals are not flipped. Inverted: Normals are flipped. Always Face Incoming Ray: Both the unflipped and flipped-normal sides are lightmapped. This can be useful for translucency in thin objects such as leaves.

Render Tree Usage

This shader is usually connected to the diffuse_illum input port of the mtlsh_shader. It may also be feeding the input port of the Sub-Surface Lightmap Write shader.