Re: [Jsbsim-devel] Matlab-JSBSim Interface

[<gt...@ma...>]

> Hello Guys,
>    Thanks a lot Wysong, Tim and Jon for the
> stimulating discussion, the ideas and the suggestions
> regarding the Matlab Interface!

No problem, Matlab is one of the best tools out there for engineering wor=
k...

>    Tim, interesting to have a GaTech Aero dude in the
> group :-) I must confess...this whole fascination with
> UAVs and helicopters goes back atleast 7 years when I
> first saw the UAV Competition website (in which GaTech
> seems to always lead :-) With the Yamaha helicopter
> (GTar?)) Its only now that I have gotten the
> opportunity, the resources...and JSBSim to actually do
> something tangible. (Well...got rejected for a PhD
> from GaTech last year :-)!)


I am only a second year undergrad, so don't give me too much credit... ha=
ha

>    As for a union...thats something I hadnt thought of
> :-) So...shall try to look into that option
> too...thanks Wysong :-)! Only problem...in the windows
> socket "recv" command...the incoming data comes in as
> a character array pointer...and in the "send"
> command...the outgoing data is also a "char
> *"...doesnt that mean that you are restricted to send
> on character arrays? As in...for the network
> layer...there is only one datatype...the "char".

On this issue, keep in mind that just because it says char, it doesn't me=
an
letters. The char datatype is 8 bits long, which means it is one byte. Yo=
u could
just as easily send binary data (you could even create the byte data type=
 to
avoid confusion, but remember it's really just a char). So yes, you are l=
imited
to sending "character arrays," but that could be any type of data you wan=
t. If
you wanted to send a union of something, you would just need to allocate =
a char
* array that has the sizeof(your_union). Then, set it equal to the &your_=
union
(address of your_union) and you've got yourself the bytes that make up th=
e
union. Then on the receiving end, you just need to have it pull out that =
char*
array and reassemble it in memory as your union. You could do this for a =
class,
union, struct, int, whatever else you could possible imagine as a datatyp=
e. Does
that make sense?

Tim Gallagher
Georgia Institute of Technology
School of Aerospace Engineering