Eric,
Let me reply again to my own message with some follow up information. We are
running on a bare bones QNX RTP 6.1 system. All the window manager/interactive
graphical cruft is omitted from this machine. I apologize if I’m not explaining
some of this well. I have a fairly strong unix background, but this is my first
exposure to QNX.
The application I am working on is 3d/OpenGL app that draws road edges and lane
boundaries on a heads up display. This all worked well in version 6.0, with the
Voodoo3/mesa/glide support. However we found that 6.1 no longer supported
mesa/glide for the Voodoo3. (Anyone know why or if there are plans to add this
back in or do a more full opengl implimentation? It would be great to have
support for GeForce cards for instance.) So any way, what we did was copy over
the missing libs from a 6.0 install to our 6.1 install in order to add the
mesa/glide/voodoo3 support back in.
This works, and we can get our app to build cleanly and run on 6.1 …
The only hitch we’ve encountered is that when the voodoo3 card flips into full
screen mode when the OpenGL app starts, it kicks into a 75Hz refresh rate mode.
Our $2000 LCD display (that can be read in sunlight) can only sync to 60Hz so
this is a significant problem for us. Back when we were running the app on
QNX version 6.0 the drivers defaulted to 60Hz. Now under 6.1 they appear to
default to 75Hz. What we are hoping for (or else we might be screwed) is to find
some way to control the refresh rate for a full screen opengl application.
Back in the Voodoo1/Voodoo2 days, glide honored an environment variable so you
could specify refresh rate (SST_SCREENREFRESH, and SSTV2_SCREENREFRESH or
something like that.) Unfortunately glide for Voodoo3 doesn’t appear to honor
any environment variables such as these.
I see that the glide API itself allows you to specify video modes, resolution and
refresh rates when you open up the display. However, the QNX implementation
buries all the glide calls under a layer of photon so it doesn’t seem to be
accessible. I’ve looked through the photon calls used to initialize the opengl
session, but the documentation for all the photon calls that are used doesn’t
seem to mention anything about screen refresh rates.
Anyone have any ideas?
Thanks in advance,
Curt.
“Curtis L. Olson” wrote:
Eric,
Thanks for your reply. I just got our machine back today and plugged in a
monitor that will display sync frequency. It is indeed sending out a 75Hz
signal. It seems like there would have to be a way to configure this, but the
-R flag to io-graphics seems to be ignored … or at least slaying
Photon/io-graphics and restarting them with the -R60 flag seems to have no
affect on the sync frequency.
Thanks,
Curt.
Hardware Support Account wrote:
Hi Curtis,
Can you verify that the refresh rate has changed - ie do you have another
monitor you can try that will display the current refresh rate? On a
system here with 6.1 and a Voodoo3 the refresh rate still defaults to 60Hz.
Thanks
Erick.
Curtis L. Olson <> curt@me.umn.edu> > wrote:
I have a QNX RTP 6.1 system connected to an LCD flat panel display.
With version 6.0, the banshee drivers defaulted to a refresh rate of 60
Hz which worked fine. However with version 6.1, the banshee drivers
appear to default to a refresh rate of 75. This is a problem because my
LCD display can’t quite sync to that refresh rate.
This is a minimal “target” machine so it is non-interactive and I don’t
have the opportunity to pull up the control panel and attempt to change
refresh rate that way.
The script that starts everything up lauches Photon, then phfontFA, then
fontsleuth, followed by io-graphics:
Photon &
waitfor /dev/photon
display_msg photon started…
phfontFA -d /usr/photon/font_repository -j -s 300k &
waitfor /dev/phfont
display_msg font server started…
fontsleuth -d /usr/photon/font_repository &
display_msg font sleuth started…
io-graphics -g640x480x16 -dldevg-banshee.so -I0 -d0x121a,0x5
-R60 &
I’m attempting to set the refresh rate using the -R60 flag. However,
the driver appears to silently ignore the -R60 option.
I’m kind of new to QNX so go easy on me. Am I missing something obvious
or is the -R flag not supported by the Voodoo3 drivers?
Thanks in advance,
Curt.
Curtis Olson Human Factors Research Lab FlightGear Project
Twin Cities > curt@hfrl.umn.edu > > curt@flightgear.org
Minnesota > http://www.menet.umn.edu/~curt
http://www.flightgear.org
