Fixed CenterQuery's torque calculation and removed dead code

FerramAerospaceResearch/FARAeroComponents/FARVesselAero.cs

@@ -308,7 +308,7 @@ private void CalculateAndApplyVesselAeroProperties()
 
         public void SimulateAeroProperties(out Vector3 aeroForce, out Vector3 aeroTorque, Vector3 velocityWorldVector, double altitude)
         {
-            FARCenterQuery center = new FARCenterQuery();
+            FARCenterQuery center = new FARCenterQuery(vessel.CoM);
 
             float pressure;
             float density;
@@ -352,7 +352,7 @@ public void SimulateAeroProperties(out Vector3 aeroForce, out Vector3 aeroTorque
             }
 
             aeroForce = center.force;
-            aeroTorque = center.TorqueAt(vessel.CoM);
+            aeroTorque = center.Torque();
         }
 
 

FerramAerospaceResearch/FARAeroComponents/VehicleAerodynamics.cs

@@ -1519,7 +1519,7 @@ private void CalculateVesselAeroProperties()
 
         public void UpdateSonicDragArea()
         {
-            ferram4.FARCenterQuery center = new ferram4.FARCenterQuery();
+            ferram4.FARCenterQuery center = new ferram4.FARCenterQuery(Vector3.zero);
 
             Vector3 worldMainAxis = _localToWorldMatrix.MultiplyVector(_vehicleMainAxis);
             worldMainAxis.Normalize();

FerramAerospaceResearch/FARGUI/FAREditorGUI/EditorAeroCenter.cs

@@ -82,10 +82,6 @@ public void UpdateAeroData(List<FARAeroPartModule> aeroModules, List<FARAeroSect
 
         void UpdateAerodynamicCenter()
         {
-            FARCenterQuery aeroSection, dummy;
-            aeroSection = new FARCenterQuery();
-            dummy = new FARCenterQuery();
-
             if((object)EditorLogic.RootPart == null)
                 return;
 
@@ -103,33 +99,33 @@ void UpdateAerodynamicCenter()
                 vel_fuzz = -0.02f * Vector3.forward;
             }
 
-            Vector3 vel = (vel_base - vel_fuzz).normalized;
-
-            for(int i = 0; i < _currentAeroSections.Count; i++)
-            {
-                FARAeroSection section = _currentAeroSections[i];
-                section.PredictionCalculateAeroForces(1, 0.5f, 100000, 0, 0.005f, vel, aeroSection);
-            }
-
-            FARBaseAerodynamics.PrecomputeGlobalCenterOfLift(aeroSection, dummy, vel, 1);
-
             Vector3 pos = Vector3.zero;//rootPartTrans.position;
             float mass = 0;
-            for(int i = 0; i < EditorLogic.SortedShipList.Count; i++)
+            for (int i = 0; i < EditorLogic.SortedShipList.Count; i++)
             {
                 Part p = EditorLogic.SortedShipList[i];
                 float tmpMass = p.mass + p.GetResourceMass();
                 mass += tmpMass;
                 pos += p.partTransform.position * tmpMass;
             }
             pos /= mass;
+            FARCenterQuery aeroSection = new FARCenterQuery(pos);
+            FARCenterQuery dummy = new FARCenterQuery(pos);
+
+            Vector3 vel = (vel_base - vel_fuzz).normalized;
+
+            for (int i = 0; i < _currentAeroSections.Count; i++)
+            {
+                FARAeroSection section = _currentAeroSections[i];
+                section.PredictionCalculateAeroForces(1, 0.5f, 100000, 0, 0.005f, vel, aeroSection);
+            }
+
+            FARBaseAerodynamics.PrecomputeGlobalCenterOfLift(aeroSection, dummy, vel, 1);
 
-            Vector3 avgForcePos = Vector3.zero;
 
             Vector3 force0, moment0;
             force0 = aeroSection.force;
-            moment0 = aeroSection.TorqueAt(pos);
-            avgForcePos += aeroSection.GetPos();
+            moment0 = aeroSection.Torque();
 
             //aeroSection.force = -aeroSection.force;
             //aeroSection.torque = -aeroSection.torque;
@@ -148,13 +144,10 @@ void UpdateAerodynamicCenter()
 
             Vector3 force1, moment1;
             force1 = aeroSection.force;
-            moment1 = aeroSection.TorqueAt(pos);
-            avgForcePos += aeroSection.GetPos();
+            moment1 = aeroSection.Torque();
 
             aeroSection.ClearAll();
 
-            avgForcePos *= 0.5f;
-
             Vector3 deltaForce = force1 - force0;
             Vector3 deltaMoment = moment1 - moment0;
 

FerramAerospaceResearch/FARGUI/FAREditorGUI/Simulation/InstantConditionSim.cs

@@ -201,7 +201,7 @@ public void GetClCdCmSteady(InstantConditionSimInput input, out InstantCondition
                 MAC += w.GetMAC() * w.S;
                 b_2 += w.Getb_2() * w.S;
             }
-            FARCenterQuery center = new FARCenterQuery();
+            FARCenterQuery center = new FARCenterQuery(CoM);
             for (int i = 0; i < _currentAeroSections.Count; i++)
             {
                 _currentAeroSections[i].PredictionCalculateAeroForces(2, (float)input.machNumber, 10000, 0, 0.005f, velocity.normalized, center);
@@ -213,7 +213,7 @@ public void GetClCdCmSteady(InstantConditionSimInput input, out InstantCondition
             output.Cy += Vector3d.Dot(centerForce, sideways);
             output.Cd += -Vector3d.Dot(centerForce, velocity);
 
-            Vector3d centerMoment = -center.TorqueAt(CoM) * 1000;
+            Vector3d centerMoment = -center.Torque() * 1000;
 
             output.Cm += Vector3d.Dot(centerMoment, sideways);
             output.Cn += Vector3d.Dot(centerMoment, liftVector);

FerramAerospaceResearch/LEGACYferram4/FARCenterQuery.cs

@@ -56,49 +56,25 @@ public class FARCenterQuery
         // Torque needed to compensate if force were applied at origin.
         public Vector3d torque = Vector3d.zero;
 
-        // Weighted average of force positions used as aid in choosing the
-        // single center location on the line of physically equivalent ones.
+        // Reference point about which to calculate torques
         public Vector3d pos = Vector3d.zero;
-        public double amount = 0.0;
 
-        /*public Vector3d GetACPosition()
+        public FARCenterQuery(Vector3 about)
         {
-            Vector3d bVec = new Vector3d();
-            bVec.x = force.y * torque.z - force.z * torque.y;
-            bVec.y = force.x * torque.z - force.z * torque.x;
-            bVec.z = force.x * torque.y - force.y * torque.x;
-
-            double approxA01, approxA02, approxA12;         //commonly used force directions
-            approxA01 = -1 / (force.z * force.z);
-            approxA02 = -1 / (force.y * force.y);
-            approxA12 = -1 / (force.x * force.x);
-
-            Vector3d acPos = new Vector3d();
-            acPos.x = force.x * force.x / (force.y * force.y * force.z * force.z) * bVec.x + bVec.y * approxA01 + bVec.z * approxA02;
-            acPos.y = force.y * force.y / (force.x * force.x * force.z * force.z) * bVec.y + bVec.x * approxA01 + bVec.z * approxA12;
-            acPos.x = force.z * force.z / (force.y * force.y * force.x * force.x) * bVec.z + bVec.y * approxA12 + bVec.x * approxA02;
-
-            acPos *= 0.5;
-            acPos += GetPos();
-
-            return acPos;
-        }*/
+            this.pos = about;
+        }
+
         public void ClearAll()
         {
             force = Vector3d.zero;
             torque = Vector3d.zero;
-            pos = Vector3d.zero;
-            amount = 0;
         }
 
         // Record a force applied at a point
         public void AddForce(Vector3d npos, Vector3d nforce)
         {
-            double size = nforce.magnitude;
             force += nforce;
-            torque += Vector3d.Cross(npos, nforce);
-            pos += npos * size;
-            amount += size;
+            torque += Vector3d.Cross(npos - pos, nforce);
         }
 
         // Record an abstracted torque or couple; application point is irrelevant
@@ -107,60 +83,10 @@ public void AddTorque(Vector3d ntorque)
             torque += ntorque;
         }
 
-        // Merge two force sets
-        public void AddAll(FARCenterQuery q2)
-        {
-            force += q2.force;
-            torque += q2.torque;
-            pos += q2.pos;
-            amount += q2.amount;
-        }
-
-        // Returns a center of weight-like average of force positions.
-        // Unless all forces are strictly parallel it doesn't mean much.
-        public Vector3d GetPos()
-        {
-            return amount > 0 ? pos / amount : Vector3d.zero;
-        }
-
-        public void SetPos(Vector3d npos)
-        {
-            pos = npos;
-            amount = 1;
-        }
-
-        // Compensating torque at different origin.
-        public Vector3d TorqueAt(Vector3d origin)
-        {
-            return torque - Vector3d.Cross(origin, force);
-        }
-
-        // Returns a point that requires minimal residual torque
-        // (or even 0 if possible) and is closest to origin.
-        // Any remaining torque is always parallel to force.
-        public Vector3d GetMinTorquePos(Vector3d origin)
-        {
-            double fmag = force.sqrMagnitude;
-            if (fmag <= 0) return origin;
-
-            return origin + Vector3d.Cross(force, TorqueAt(origin)) / fmag;
-        }
-
-        public Vector3d GetMinTorquePos()
-        {
-            return GetMinTorquePos(GetPos());
-        }
-
-        // The physics engine limits torque that can be applied to a single
-        // object. This tries to replicate it based on results of experiments.
-        // In practice this is probably not necessary for FAR, but since this
-        // knowledge has been obtained, might as well turn it into code.
-        public static float TorqueClipFactor(Vector3 torque, Rigidbody body)
+        // Compute torque.
+        public Vector3d Torque()
         {
-            Vector3 tq = Quaternion.Inverse(body.rotation * body.inertiaTensorRotation) * torque;
-            Vector3 tensor = body.inertiaTensor;
-            float acceleration = new Vector3(tq.x / tensor.x, tq.y / tensor.y, tq.z / tensor.z).magnitude;
-            return Mathf.Max(1.0f, acceleration * Time.fixedDeltaTime / body.maxAngularVelocity);
+            return torque;
         }
     }
 }