Declare external reactions in C++ code, rather than in XML configuration.

[scotteh432]

Hi all,

I'm embedding JSBSim inside another program for a project I am working on involving aircraft towing systems. To get this to work, it would be very nice to be able to declare an External Reaction via the C++ code rather than in the XML configuration files. I've read through the documentation on the FGExternalReactions, which indicates that this should be possible, but alas, I cannot figure out how.

I've tried accessing the FGExternalReactions through the GetExternalReactions from the FGFDMExec class. But I can't seem to do anything with it once I have it without causing my code to not compile. I believe I should be able to call the Load() method to initialize an external reaction from an XML element. But I can't seem to call this method without causing my code to fail to compile.

// Setup directories for JSBSim execution
JSBSim::FGFDMExec> f;
f.SetRootDir(MyRootDir);
f.SetAircraftPath(MyAircraftDir);
f.SetEnginePath(MyEngineDir);
f.SetSystemsPath(MySystemsDir);
f.SetOutputPath(MyOurputDir);

// Ok, here! How would I declare an External Reaction?
shared_ptr<JSBSim::FGExternalReactions> ptr = f.GetExternalReactions();   // Is this a step in right direction? 
ptr->Load(someXmlElement);  // This does not work, my compiler complains I'm doing something wrong.

// Load script and launch init
f.LoadScript(MyScriptDir);
f.RunIC();

// Execution loop is down here; omitted for this snippet of code posted to the JSBSim forum

Any help in solving this issue would be much appreciated. I'm willing to accept the answer of "just use the XML configuration files" if there's no good way to do this, I just want to explore this avenue first, as I believe it will make the workflow of my project cleaner. Thank you very much for your time.

[bcoconni]

// Ok, here! How would I declare an External Reaction?
shared_ptr<JSBSim::FGExternalReactions> ptr = f.GetExternalReactions();   // Is this a step in right direction? 
ptr->Load(someXmlElement);  // This does not work, my compiler complains I'm doing something wrong.

These lines look good to me however you should call them after your model has been loaded i.e. after f.LoadScript(MyScriptDir).

If that does not help, it would be helpful to provide the error message that your compiler is returning.