All MaterialX Lama materials need to begin with attaching a LamaSurface node to your geometry.
LamaSurface allows you to create a material and define different materials for the front and back facing surface.
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Material Properties
Material Sides
Defines the number of sides a material has, 1 (default) or 2 where a backside can be a different material look.
The above example demonstrates a leaf material on the front side and a gold material on the back side, creating ... GoldLeaf
Material Front
This is the material that defines the front facing result.
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This connection is available if enabled in the Features below. This connection allows you to define the visibility of a surface using a pattern connection.
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Features
Compute Presence
Allows the creation and connection of a presence setting or connected pattern to control the visibility of the object.
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This enables or disables the computation of opacity for transmissive materials (like glass). Leaving it off can speed up a render for possible draft or preview renders.
Presence / Opacity Cached
Whether the renderer should cache presence (and opacity) or not. Caching these properties will lead to faster tracing, especially for shadow queries, but can lead to a less sharp result than uncached presence/opacity. (Note that checking either subsurface or interior computation will automatically disable presence/opacity caching.)
Computer Subsurface
This enables or disables the computation of subsurface scattering (when in use). Leaving this off can speed up draft or preview renders.
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