The RenderMan Interface - Paul Bourke

RIB BINDING
Polygon ...parameterlist...
The number of vertices in the polygon is determined implicitly by the number of
elements in the required position array.
EXAMPLE
RtPoint points[4] = ( 0.0, 1.0, 0.0, 0.0, 1.0, 1.0,
0.0, 0.0, 1.0, 0.0, 0.0, 0.0);
RiPolygon(4, RI P, (RtPointer)points, RI NULL);
SEE ALSO
RiGeneralPolygon, RiPointsGeneralPolygons, RiPointsPolygons
An example of the definition of a “Gouraud-shaded” polygon is:
RtPoint points[4];
RtColor colors[4];
RiPolygon( 4, ”P”, (RtPointer)points, ”Cs”, (RtPointer)colors, RI NULL);
A “Phong-shaded” polygon is given by:
RtPoint points[4];
RtPoint normals[4];
RiPolygon( 4, ”P”, (RtPointer)points, ”N”, (RtPointer)normals, RI NULL);
RiGeneralPolygon ( RtInt nloops, RtInt nvertices[], ...parameterlist...)
Define a general planar concave polygon with holes. This polygon is specified by
giving nloops lists of vertices. The first loop is the outer boundary of the polygon;
all additional loops are holes. The array nvertices contains the number of vertices in
each loop, and has length nloops. The vertices in all the loops are concatenated into
a single vertex array. The length of this array, n, is equal to the sum of all the values
in the array nvertices.
parameterlist is a list of token-array pairs where each token is one of the standard
geometric primitive variables or a variable that has been defined with RiDeclare. The
parameter list must include at least position (”P”) information. If a primitive variable
is of class vertex or varying, the array contains n elements of the type corresponding
to the token. If the variable is uniform or constant, there is a single element of that
type. The number of floats associated with each type is given in Table 5.1, Standard
Geometric Primitive Variables. The interpretation of these variables is the same as for
a convex polygon.
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