Similarly to the color source shader that specifies the color of a surface, a transparency source is used to define how transparent or opaque a surface is, and thus how much light is able to pass through it. Internally, the rendering engine records transparencies as color values - which may be thought of as representing filters - and this enables complex surface effects to be created.
Transparency source shaders range from a simple plain uniform transparency to more complex regular or irregular eroded patterns that would be difficult to represent using modeling techniques.
We provide herewith names and descriptions of transparency source shaders:
"eroded"
Surface erosion.
"glow"
Glow effect around lights.
"label"
A transparency shader specific for labelling.
"plain"
A plain, uniform transparency.
"base"
Base transparency derived from values supplied at vertices of polygonal
geometry.
"wrapped checker"
A checker-board transparency pattern.
"wrapped grid"
A grid transparency pattern.
"wrapped image"
A wrapped texture to provide image transparency mapping.
"wrapped mask"
Wrapped image in which the red channel is interpreted as the transparency alpha value.
"wrapped square"
A square transparency pattern.