The RenderMan Interface - Paul Bourke

An atmosphere shader is a volume shader that is used to modify rays traveling towards
the eye (i.e., camera rays). Even renderers that do not support the optional Ray Tracing
capability can still apply atmosphere shaders to any objects directly visible to the camera.
The RenderMan Interface includes two standard volume shaders: ”fog” and ”depthcue”.
The definitions of these volume shaders are given in Appendix A, Standard RenderMan
Interface Shaders. The parameters controlling these volumes are given in Table 4.10, Standard
Volume Shader Parameters.
RiAtmosphere ( RtToken shadername, ...parameterlist...)
This procedure sets the current atmosphere shader. shadername is the name of an atmosphere
shader. If shadername is RI NULL, no atmosphere shader is used.
RIB BINDING
Atmosphere shadername ...parameterlist...
EXAMPLE
Atmosphere ”fog”
SEE ALSO
RiDisplacement, RiSurface
Volume Name Parameter Type Default Description
depthcue mindistance float 0.0 Distance when brightest
maxdistance float 1.0 Distance when dimmest
background color color ”rgb” (0,0,0) Background color
fog distance float 1.0 Exponential extinction
distance
background color color ”rgb” (0,0,0) Background color
Table 4.10: Standard Volume Shader Parameters
RiInterior ( RtToken shadername, ...parameterlist...);
This procedure sets the current interior volume shader. shadername is the name of a
volume or atmosphere shader. If shadername is RI NULL, the surface will not have
an interior shader.
RIB BINDING
Interior shadername ...parameterlist...
EXAMPLE
Interior ”water”
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