The RenderMan Interface - Paul Bourke

RIB BINDING
Color c0 c1... cn
Color [c0 c1... cn]
EXAMPLE
RtColor blue = { .2, .3, .9};
RiColor (blue);
Color [.2 .3 .9]
SEE ALSO
RiOpacity, RiColorSamples
RiOpacity ( RtColor color )
Set the current opacity to color. The color component values must be in the range
[0,1]. Normally there are three components in the color (red, green, and blue), but this
may be changed with RiColorSamples. If the opacity is 1, the object is completely
opaque; if the opacity is 0, the object is completely transparent.
RIB BINDING
Opacity c0 c1... cn
Opacity [c0 c1... cn]
EXAMPLE
Opacity 0.5 1 1
SEE ALSO
RiColorSamples, RiColor
4.2.2 Texture coordinates
The Shading Language allows precalculated images to be accessed by a set of two-dimensional
texture coordinates. This general process is referred to as texture mapping. Texture access in
the Shading Language is very general since the coordinates are allowed to be any legal expression.
However, the texture access functions (in Part II, see the sections on Basic texture
maps) often use default texture coordinates related to the surface parameters.
All the parametric geometric primitives have surface parameters (u,v) that can be used
as their texture coordinates (s,t). Surface parameters for different primitives are normally
defined to lie in the range 0 to 1. This defines a unit square in parameter space. Section
5, Geometric Primitives defines the position on each surface primitive that the corners of
this unit square lie. The texture coordinates at each corner of this unit square are given by
providing a corresponding set of (s,t) values. This correspondence uniquely defines a 3x3
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