HP SVA V2.0 Parallel Compositing Reference Guide

pcFrameResultChannel(3)
NAME
pcFrameResultChannel -- Retrieves resultant pixels for the frame.
Synopsis
PCerr pcFrameResultChannel(
PCcontext ctx,
PCid frameId,
PCuint xOffset,
PCuint yOffset,
PCuint width,
PCuint height,
PCuint channelType,
PCchannel channel
);
Parameters
ctx
The context for this frame.
frameId The unique ID generated for this frame by pcFrameBegin.
xOffset
The x offset in pixels from the origin of the output.
yOffset
The y offset in pixels from the origin of the output.
width
The width of the result in pixels.
height
The height of the result in pixels.
channelType
The channel to return.
channel A PCchannel that is initialized for accessing the channel specified by this
function.
Returns
On successful completion, this function returns the status PC_NO_ERROR and the output
parameter channel.
Description
This function retrieves output pixels of the frame and corresponds to the Retrieve the needed
channels Step in Table 1-2 (page 15) in the Parallel Compositing Library Reference Guide.
This function blocks until the pixel information requested by the parameters is available. If a
program needs to check on the status of a result without blocking, it can call
pcFrameResultQuery.
The parameters of the function describe the pixel information to be returned. The first two
parameters (ctx and frameId) identify the frame of interest. This call must be made following the
host’s call to pcFrameEnd for the frame specified by the frameId parameter.
The next four parameters (xOffset, yOffset, width, and height) describe the result’s location on the
output. The xOffset and yOffset are relative to the origin of the output. The result must be within
the boundaries of the output described by the context properties for this host.
The final two parameters (channelType and channel) describe the type of pixel information to be
delivered to the calling program. channelType states the channel (color or depth) to be delivered,
and on a successful return, the actual channel information is provided to the calling program in
the parameter channel.
The buffers produced by this function are two-dimensional arrays. The elements of the array are
not necessarily contiguous. You can retrieve element (x,y) in any channel buffer as follows,
where channel is the structure passed as the channel parameter:
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