HP SVA V2.0 Parallel Compositing Reference Guide

To distinguish extensions from core library features, the following naming conventions exist:
• A unique extension name of the form, PC_<type>_<name> is associated with each extension.
If more than one vendor supports the extension, <type> is EXT. If a single vendor supports
the extension, <type> designates that vendor. For example:
— PC_EXT_io_count is an extension supported by more than one vendor.
— PC_HP_frame_output is an extension supported by HP.
• All functions defined by an extension have names of the form, <function><type>. If more
than one vendor supports the extension, <type> is EXT. If a single vendor supports the
extension, <type> designates that vendor. For example:
— pcFrameGLAddFrameletEXT is an extension function supported by more than one
vendor.
— pcFrameWaitOutputHP is an extension function supported by HP.
• All PCenum values defined by the extension have names of the form, <name>_<type>. If
more than one vendor supports the extension, <type> is EXT. If a single vendor supports
the extension, <type> designates that vendor. For example:
— PC_WRITE_COUNT_EXT is a PCenum extension supported by more than one vendor.
— PC_WRITE_COUNT_HP is a PCenum extension supported by HP.
EXT extensions can be promoted to required core features in later versions of the Parallel
Compositing Library specification. When this occurs, the extension specifications are merged
into the core part of this specification. Promoted functions and PCenum values have the EXT or
_EXT suffix removed.
As a migration aid, Library implementations of any later versions should continue to export the
extension name, and function and PCenum names with the EXT or _EXT suffix .
B.1.1.1 PC_EXT_io_count Extension
This extension returns statistics on the additional network traffic added by the Library. Table B-2
describes the additional properties added to each context for this extension.
There are no additional functions.
Table B-2 Summary of PC_EXT_io_count Properties
DescriptionCan Change After
Context Create
Can Set
On
Context
Create
TypePropertyValue
This property returns the number of bytes
read by the local host from all other hosts
since the last retrieval of this property.
Retrieving the property resets the property
to 0. Although the property is local and
applies to a host, the property can only be
retrieved for the local host.
nonointeger
PC_READ_COUNT_EXT
host-specific
This property returns the number of bytes
written by the local host to all other hosts
since the last retrieval of this property.
Retrieving the property resets the property
to 0. Although the property is local and
applies to a host, the property can only be
retrieved for the local host.
nonointeger
PC_WRITE_COUNT_EXT
B.1.1.2 PC_EXT_cur_gfx_ctx Extension
This extension provides support to the Library for extracting framelet pixels directly from a
graphics card. Using this extension, the program calls pcFrameAddGLFramelet as a replacement
for pcFrameAddFramelet. The extension function reads pixels from the current openGL context
to fill the framelet.
78 Functions and Properties of Extensions