From 0d342f526ebe28ad2ad7558611f2cb55135f21e6 Mon Sep 17 00:00:00 2001
From: Bertrand Coconnier <bcoconni@users.sourceforge.net>
Date: Sat, 11 Mar 2017 14:00:20 +0100
Subject: [PATCH] Exports the parameters of JSBSim ground reactions friction
 resolver to the property tree for debugging.

---
 src/FDM/JSBSim/models/FGAccelerations.cpp | 9 ++++++++-
 src/FDM/JSBSim/models/FGAccelerations.h   | 2 ++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/FDM/JSBSim/models/FGAccelerations.cpp b/src/FDM/JSBSim/models/FGAccelerations.cpp
index 62fc0e977..048db3d9a 100644
--- a/src/FDM/JSBSim/models/FGAccelerations.cpp
+++ b/src/FDM/JSBSim/models/FGAccelerations.cpp
@@ -104,6 +104,8 @@ bool FGAccelerations::InitModel(void)
   vGravAccel.InitMatrix();
   vBodyAccel.InitMatrix();
 
+  maxiter = 50;
+  matrixSize = iter = 0;
   return true;
 }
 
@@ -255,6 +257,7 @@ void FGAccelerations::ResolveFrictionForces(double dt)
   FGColumnVector3 vdot, wdot;
   vector<LagrangeMultiplier*>& multipliers = *in.MultipliersList;
   size_t n = multipliers.size();
+  matrixSize = n;
 
   vFrictionForces.InitMatrix();
   vFrictionMoments.InitMatrix();
@@ -303,7 +306,7 @@ void FGAccelerations::ResolveFrictionForces(double dt)
   }
 
   // Resolve the Lagrange multipliers with the projected Gauss-Seidel method
-  for (int iter=0; iter < 50; iter++) {
+  for (iter=0; iter < maxiter; iter = iter+1) {
     double norm = 0.;
 
     for (unsigned int i=0; i < n; i++) {
@@ -384,6 +387,10 @@ void FGAccelerations::bind(void)
   PropertyManager->Tie("forces/fbx-gear-lbs", this, eX, (PMF)&FGAccelerations::GetGroundForces);
   PropertyManager->Tie("forces/fby-gear-lbs", this, eY, (PMF)&FGAccelerations::GetGroundForces);
   PropertyManager->Tie("forces/fbz-gear-lbs", this, eZ, (PMF)&FGAccelerations::GetGroundForces);
+
+  iter = PropertyManager->CreatePropertyObject<int>("numerical/friction-resolver/iterations");
+  maxiter = PropertyManager->CreatePropertyObject<int>("numerical/friction-resolver/max-iterations");
+  matrixSize = PropertyManager->CreatePropertyObject<int>("numerical/friction-resolver/matrix-size");
 }
 
 //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
diff --git a/src/FDM/JSBSim/models/FGAccelerations.h b/src/FDM/JSBSim/models/FGAccelerations.h
index 85dda88bb..b80456cd2 100644
--- a/src/FDM/JSBSim/models/FGAccelerations.h
+++ b/src/FDM/JSBSim/models/FGAccelerations.h
@@ -40,6 +40,7 @@ INCLUDES
 
 #include <vector>
 
+#include "simgear/props/propertyObject.hxx"
 #include "models/FGModel.h"
 #include "math/FGColumnVector3.h"
 #include "math/LagrangeMultiplier.h"
@@ -391,6 +392,7 @@ private:
   FGColumnVector3 vGravAccel;
   FGColumnVector3 vFrictionForces;
   FGColumnVector3 vFrictionMoments;
+  simgear::PropertyObject<int> iter, maxiter, matrixSize;
 
   int gravType;
   bool gravTorque;