First of all, thanks to all for your responses and help with this. I have made some progress with this and just wanted to report back for those interested. I went through the net_fdm.hxx and native_fdm.cxx files and set all variables to either long or double, as appropriate. I also made sure that there was no casting involved in setting those values (at least no casting within the native_fdm.cxx code). In doing so, I was able to receive more appropriate values out of FlightGear; however, it did appear that some of the values got "shifted". For example, the left and right aileron positions were being reported in the right aileron and rudder variables (but at least they were the correct values) -- the rudder variable comes immediately after the right aileron in the variable declaration sequence.
Also, I uncommented out a line in the code in the process() method to print out the size of the buffer that is being sent. According to this statement, the size of the buffer (or the class structure in this case) is 640 bytes. However, when I do the same thing on my side to print out the size of the structure I should be receiving, I get 632 bytes. If I manually calculate what the size should be, giving 4 bytes for longs, 8 bytes for doubles, I get 632. I don't know where the extra 8 bytes come from. Anyway, I'm real interested in getting this to work. As you may have noticed by my e-mail address, I work at NASA Langley. I'm working on a project that will allow pilots and researchers to fly and evaluate scale model planes (in particular, a 757). The plane will obviously be flown remotely. We will eventually be using a Matlab (Simulink) model as the flight model, but until the model is complete, FlightGear is a very nice substitute -- and we need something to help build other software components. But in addition to having a flight model (whether it's Simulink or FlightGear), we also need various displays to show the "health" and control responses of the model. I'm currently trying to build the displays to show the control responses, and to support this, I need the data out of FlightGear. BTW - I am compiling the code using Cygwin. My code is built using VC++ 6.0. chuck _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d
