Josh wanted a compression-m value exported for gear, so he can animate

them more accurately.

src/FDM/YASim/Gear.cpp

@@ -180,9 +180,11 @@ void Gear::calcForce(RigidBody* body, State *s, float* v, float* rot)
     // First off, make sure that the gear "tip" is below the ground.
     // If it's not, there's no force.
     float a = ground[3] - Math::dot3(_pos, ground);
+    _compressDist = -a;
     if(a > 0) {
 	_wow = 0;
 	_frac = 0;
+        _compressDist = 0;
         _rollSpeed = 0;
         _casterAngle = 0;
 	return;

src/FDM/YASim/Gear.hpp

@@ -66,6 +66,7 @@ public:
     void getForce(float* force, float* contact);
     float getWoW();
     float getCompressFraction();
+    float getCompressDist() { return _compressDist; }
 
 private:
     float calcFriction(float wgt, float v);
@@ -84,6 +85,7 @@ private:
     float _contact[3];
     float _wow;
     float _frac;
+    float _compressDist;
     double _global_ground[4];
     float _global_vel[3];
     float _casterAngle;

src/FDM/YASim/YASim.cxx

@@ -461,6 +461,7 @@ void YASim::copyFromYASim()
 	node->setBoolValue("has-brake", g->getBrake() != 0);
 	node->setBoolValue("wow", g->getCompressFraction() != 0);
 	node->setFloatValue("compression-norm", g->getCompressFraction());
+	node->setFloatValue("compression-m", g->getCompressDist());
         node->setFloatValue("caster-angle-deg", g->getCasterAngle() * RAD2DEG);
         node->setFloatValue("rollspeed-ms", g->getRollSpeed());
     }