Tim's multiple view features are very powerful, and I'm amazed at how fast
things run on medium and even lower range hardware.
Tim's updates support two major modes of operation.
1. If you have multiple monitors connected to your computer and setup as
separate independent displays (i.e. you can't drag a window back and forth
between the monitors, and can't create a window that spans multiple
monitors) then you can configure FlightGear to open up a separate window on
each display and draw a unique view perspective in each window. (And if you
want you can configure flightgear to open multiple windows on a single
2. If you have multiple monitors connected as one larger virtual display,
you can configure FlightGear to open up one large window that spans all your
displays, but then separate that large window into individual cameras and
still draw a unique perspective on each display.
In addition, each view is highly configurable, no matter how your displays
- You can setup a distinct field of view for each display, so you can create
a seamless outside world with different size monitors.
- If you wish, you can define each view in terms of the low level view
frustum parameters, so you can carefully measure your monitor/display layout
and configure each view to match your physical layout exactly ... including
asymmetric view frustums if need be. Otherwise you can still define your
views in terms of a simpler (but less flexible) horizontal/vertical field of
- You can specify the horizontal and vertical offset from center for each
display. This allows you to spread out your monitors to account for the
physical gap between displays ... this allows you to create an even more
seamless virtual world where runway lines and horizon lines start in the
correct place on the next monitor when they run off the edge of the first.
Imagine taking a large poster, cutting it into pieces and the separating the
pieces from each other by a little bit ... none of the straight lines in the
original image will pass straight through in the separated/stretched
version. Now imagine taking that same picture and cutting strips out of it,
but leaving the sections where they were originally. Straight lines are
preserved between adjacent pieces. This is the sort of thing I'm talking
- ATI (the ATI that makes graphics chips and cards) used a simplified
(prerelease) version of this feature to demo 8 screens being driven from a
single computer at SigGraph this year.
- Enter the Matrox Triple Head to Go (google it if you haven't heard of
it.) This is just a little box, but to the computer, it looks like one
giant 3x wide monitor. It plugs into your computer on one side, and on the
other side you plug in 3 actual monitors. So you get up to 3 monitors
without your computer needing to know anything about it, and even on video
cards with only one external display connector (like a laptop.) Using the
2nd mode of operation described above, I divided my one big window into 3
camera views and was able to draw about 120 degree wrap around field of view
on 3 displays.
In addition, the laptop's built in display was still available for ... oh
... let's say an operator console:
- I've done an extended version of this same theme where the front 3
monitors were driven by a single PC with the Matrox Triple Head 2 Go box,
and the 90 degree left/right displays (2 displays) were driven by a second
computer using stock dual head nvidia hardware.
None of this unfortunately ends up in my own house. I'm stuck with ye-olde
17" LCD dispay (analog) for my view into the virtual world. :-)
So to summarize, I'm extremely impressed and happy with how well Tim
leveraged OSG's multiple window and multiple camera features and how well
they are integrated into FlightGear.
In a former life (circa year 2000) I used to work on a driving simulator
that was powered by a $250,000 Sgi Onyx. This system had the ability to
take the 4 quadrants of your display and pipe that to 4 separate monitors.
Unfortunately, the hardware started bogging down and the best we could do
was three 640x480 displays at about 15 fps.
Fast forward to 8 years later and you can do three 1280x1024 displays at
60fps (easily) running on hardware that easily costs less than $1000. (Oh
and that Sgi would break down every couple months, requiring board
replacements ... and those boards ran $30k to $60k each and required a
specially trained sgi tech to install them. We paid $10k a year for our
hardware maintenance contract.)
On Wed, Oct 15, 2008 at 2:38 AM, Erwan MAS wrote:
> On Tue, Oct 14, 2008 at 04:01:55PM -0400, Matthew Tippett wrote:
> > Hi,
> > I don't know if Tim has documented the OSG Camera work that he has done.
> > it removes most of the requirements for multiple instances and runs
> > very well on modest hardware. Of course it depends on what you are
> > doing for the mode of operation.
> The OSG Camera can work with 2 PC each with 2 screens ?
> / Erwan MAS /\
> | mailto:[EMAIL PROTECTED] |_/
> ___|________________________________________________________ |
> This SF.Net email is sponsored by the Moblin Your Move Developer's
> Build the coolest Linux based applications with Moblin SDK & win great
> Grand prize is a trip for two to an Open Source event anywhere in the world
> Flightgear-devel mailing list
Curtis Olson: http://baron.flightgear.org/~curt/
This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
Flightgear-devel mailing list