The RenderMan Interface - Paul Bourke

not support the special projection specified, it is ignored and an orthographic projection
is used. If RiProjection is not called, the screen transformation defaults to the
identity matrix, so screen space and camera space are identical.
RIB BINDING
Projection ”perspective” ...parameterlist...
Projection ”orthographic”
Projection name ...parameterlist...
EXAMPLE
RiProjection (RI ORTHOGRAPHIC, RI NULL);
RtFloat fov = 45.0;
RiProjection (RI PERSPECTIVE, ”fov”, &fov, RI NULL);
SEE ALSO
RiPerspective, RiClipping
RiClipping ( RtFloat near, RtFloat far )
Sets the position of the near and far clipping planes along the direction of view.
near and far must both be positive numbers. near must be greater than or equal
to RI EPSILON and less than far. far must be greater than near and may be equal to
RI INFINITY. These values are used by RiProjection to generate a screen projection
such that depth values are scaled to equal zero at z=near and one at z=far. Notice
that the rendering system will actually clip geometry which lies outside of z=(0,1)
in the screen coordinate system, so non-identity screen transforms may affect which
objects are actually clipped.
For reasons of efficiency, it is generally a good idea to bound the scene tightly with
the near and far clipping planes.
RIB BINDING
Clipping near far
EXAMPLE
Clipping 0.1 10000
SEE ALSO
RiBound, RiProjection, RiClippingPlane
RiClippingPlane ( RtFloat x, RtFloat y, RtFloat z, RtFloat nx, RtFloat ny, RtFloat nz)
Adds a user-specified clipping plane. The plane is specified by giving any point on
its surface, (x, y, z), and the plane normal, (nx, ny, nz). All geometry on the positive
side of the plane (that is, in the direction that the normal points) will be clipped from
the scene. The point and normal parameters are interpreted as being in the active
local coordinate system at the time that the RiClippingPlane statement is issued.
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