The RenderMan Interface - Paul Bourke

EXAMPLE
RiFrameAspectRatio (4.0/3.0);
SEE ALSO
RiDisplay, RiFormat
RiScreenWindow ( RtFloat left, RtFloat right, RtFloat bottom, RtFloat top )
This procedure defines a rectangle in the image plane that gets mapped to the raster
coordinate system and that corresponds to the display area selected. The rectangle
specified is in the screen coordinate system. The values left, right, bottom, and top are
mapped to the respective edges of the display.
The default values for the screen window coordinates are:
(–frameaspectratio, frameaspectratio, –1, 1).
if frameaspectratio is greater than or equal to one, or
(–1, 1, –1/frameaspectratio, 1/frameaspectratio).
if frameaspectratio is less than or equal to one. For perspective projections, this default
gives a centered image with the smaller of the horizontal and vertical fields of
view equal to the field of view specified with RiProjection. Note that if the camera
transformation preserves relative x and y distances, and if the ratio
abs(right − left)
abs(top − bottom)
is not the same as the frame aspect ratio of the display area, the displayed image will
be distorted.
RIB BINDING
ScreenWindow left right bottom top
ScreenWindow [left right bottom top]
EXAMPLE
ScreenWindow -1 1 -1 1
SEE ALSO
RiCropWindow, RiFormat, RiFrameAspectRatio, RiProjection
RiCropWindow ( RtFloat xmin, RtFloat xmax, RtFloat ymin, RtFloat ymax )
Render only a subrectangle of the image. This command does not affect the mapping
from screen to raster coordinates. This command is used to facilitate debugging regions
of an image, and to help in generating panels of a larger image. These values
are specified as fractions of the raster window defined by RiFormat and RiFrameAspectRatio,
and therefore lie between 0 and 1. By default the entire raster window is
rendered. The integer image locations corresponding to these limits are given by
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