On 11/30/06, Vikas N Kumar <vikasnkumar@users.sourceforge.net> wrote:
Hi All
I have an AMD64 machine that runs a 64-bit flavor of GNU/Linux.
I have a Sun SPARC64 machine that runs Solaris 7 with a gnu compiler toolset.

Now if I want to use both these machines to run FlightGear, will it
work. Say I run Flightgear on the AMD64 and the panel display of FG on
SPARC64.
1)  Will it work ?

This should work.  The binary udp packet transmission does it's best to account for platform and endianess differences.

2)  Is data transfer between two flight gear apps done only via XML ?

I've always done binary udp packets ... I'm not aware of an XML option for transfering data.

3) Isn't XML very slow ?

It could be depending on what you are doing or it could be fast enough, again depending on what you are doing.

Remember that the endianness of the AMD64 and SPARC64 are different.

As of today I do not have a good Gfx card for the SPARC64, so I have not tried
running/compiling FG on it, but if this scenario works, I will spend
some cash/time/effort getting one.

4) If it does not work, and if I install Linux on the SPARC64, will
the endianness make a difference. Will it work then ?

FlightGear transmits the udp binary packets in network byte order so endianess shouldn't be a problem.  We've also been careful to make sure we use a minimum of 4 bytes data values (even for booleans).  This greatly reduces the chance that you'll run into a packing mismatch between two different systems or compilers.  That's no guarantee that you can't find a way to trip it up, but the current system has been shown to work on a great variety of systems.

Curt.
--
Curtis Olson - University of Minnesota - FlightGear Project
http://baron.flightgear.org/~curt/   http://www.humanfirst.umn.edu/  http://www.flightgear.org
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