SunForum 3D will interoperate with earlier versions of SunForum as well as
other H.323/T.120 based conferencing applications, but accelerated sharing
will be available only from a SunForum 3D host sharing the application
to the SunForum 3D participant(s) in the conference.
When SunForum 3D sharing is enabled, the OpenGL image data is grabbed,
compressed, and sent to all participants in a conference over a private
channel. The participants in turn receive the data, decompress it, and
display the image. Various options are available to configure this pipeline
that displays the 3D application. You can change some of these options
dynamically (from the SunForum 3D GUI) while a conference or sharing is
in progress. You set other options in a SunForum 3D system or user specific
configuration file.
There might be a noticeable slowdown in the frame rate of the 3D OpenGL
application being shared. This is expected behavior, since each frame needs
to be grabbed, compressed, sent to all receivers, decompressed, and
displayed. You can control this behavior and performance using the
SunForum 3D conference manager interface 3D controls.
SunForum 3D Operation Control Descriptions
The 3D toggle button
When this button is turned on (checked), the SunForum 3D application sharing
is enabled. When it is turned off (unchecked), the SunForum 3D application
sharing is disabled. In the latter case, application sharing still takes
place (as it does with SunForum). However, there is a significant degradation
in the frame rate and the integrity of frames on the viewers as compared to
the SunForum 3D application sharing mode.
Toggle this button off when there are non-SunForum 3D compliant parties in
a conference who need to see the application at some moments during the
conference. Turning the 3D application sharing toggle button off impairs
performance, but it makes the frames visible to the non-SunForum 3D nodes.
Higher speed - Better quality slider
Frames are compressed at one end and decompressed at the other. The CODECs
used for compression/decompression are discussed in Setting Parameters for
3D Application Sharing, but some of the CODECs allow for a parameter which
balances the compression ratio versus the loss in image detail. If the
currently selected CODEC has such a parameter, then the slider will be
enabled, otherwise the slider is inactive.
Depending on the CODEC, on the size of the frames, CPU processing
capabilities, and the available bandwidth, the effects of moving the slider
might or might not be visible. It is best for users to set the slider in
the middle, and then adjust it left or right depending on the performance,
image quality, and other needs.
NOTE that the slider is effective for the sending side of the application
(application sharing host) only.
Allow frame skip (send)
Frames are grabbed, compressed, sent over the network, decompressed, and
displayed. By default (when this button is not checked), every frame generated
on the host is sent and seen on all other SunForum 3D participants in the
conference. Selecting "Allow frame skip (send)" slows down the application
being shared to whatever the bottleneck might be (typically, either the
compression or the network congestion).
When you select "Allow frame skip (send)," SunForum 3D is allowed to skip
the transmission of some/certain frames in the application (if the rest of
the pipeline is busy) so that the OpenGL application is not slowed down as much.
Setting this toggle on a viewer system will have no effect on the application
sharing host, that is, this toggle is effective only for the application
sharing host.
NOTE that this button has an effect only on the SunForum 3D hosting the shared
application.
Allow frame skip (rec)
This toggle button is the equivalent of the frame skip toggle button on the
receiving end. By default (when this button is not checked), every frame
received is decompressed and displayed.
When you select the "Allow frame skip (rec)," SunForum 3D skips the display
of some frames so as to show the most recent frame (generated at the host)
sooner.
For example, if the system is a low end system and decoding and/or displaying
are relatively slow compared to the other systems in a conference, then the
low end system would, in principle, slow down the frame rate for everybody in
the conference. In this case, the user at the low end system could press and
select this toggle button, thus enabling frame skipping and not slowing down
the host and the others in the conference as much.
Setting this toggle on a viewer system will have no effect on the application
sharing host, that is, this toggle is effective only for the receiving system.
SunForum 3D Configuration Files
The entries in the /opt/SUNWsf3d/config/system-config configuration file
contain various parameters that control the behavior of the 3D application
sharing. This file can be edited, although you need to be superuser to edit
the file. The parameters are explained in the configuration file.
A user editable copy of this file exists in $HOME/.sunforum/.sf3d-user-config.
If this file does not exist, make a copy of the system-config file. This file
will also be updated by SunForum 3D, depending on GUI selections made by the
user while running SunForum 3D.
NOTE that when entries are in both .sf3d-user-config and system-config files,
then the values of the parameters in .sf3d-user-config take precedence over
those in system-config.
Copyright 1997 - 2001Data
Connection Ltd.
Copyright1998 - 2001Sun
Microsystems, Inc