12 files changed, 865 insertions, 516 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index 4c195e1..1dfc420 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -307,7 +307,7 @@ public sealed class BSCharacter : BSPhysObject
         }
         if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
         {
-            float waterHeight = PhysicsScene.GetWaterLevelAtXYZ(_position);
+            float waterHeight = PhysicsScene.TerrainManager.GetWaterLevelAtXYZ(_position);
             if (Position.Z < waterHeight)
             {
                 _position.Z = waterHeight;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
index dbc9039..3a73fba 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
@@ -80,10 +80,10 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         private Quaternion m_referenceFrame = Quaternion.Identity;
 
         // Linear properties
+        private BSVMotor m_linearMotor = new BSVMotor("LinearMotor");
         private Vector3 m_linearMotorDirection = Vector3.Zero;          // velocity requested by LSL, decayed by time
         private Vector3 m_linearMotorOffset = Vector3.Zero;             // the point of force can be offset from the center
         private Vector3 m_linearMotorDirectionLASTSET = Vector3.Zero;   // velocity requested by LSL
-        private Vector3 m_newVelocity = Vector3.Zero;                   // velocity computed to be applied to body
         private Vector3 m_linearFrictionTimescale = Vector3.Zero;
         private float m_linearMotorDecayTimescale = 0;
         private float m_linearMotorTimescale = 0;
@@ -93,6 +93,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         // private Vector3 m_linearMotorOffset = Vector3.Zero;
 
         //Angular properties
+        private BSVMotor m_angularMotor = new BSVMotor("AngularMotor");
         private Vector3 m_angularMotorDirection = Vector3.Zero;         // angular velocity requested by LSL motor
         // private int m_angularMotorApply = 0;                            // application frame counter
         private Vector3 m_angularMotorVelocity = Vector3.Zero;          // current angular motor velocity
@@ -124,6 +125,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     // Therefore only m_VehicleBuoyancy=1 (0g) will use the script-requested .Z velocity.
 
         //Attractor properties
+        private BSVMotor m_verticalAttractionMotor = new BSVMotor("VerticalAttraction");
         private float m_verticalAttractionEfficiency = 1.0f;        // damped
         private float m_verticalAttractionTimescale = 500f;         // Timescale > 300  means no vert attractor.
 
@@ -152,10 +154,12 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     m_angularDeflectionTimescale = Math.Max(pValue, 0.01f);
                     break;
                 case Vehicle.ANGULAR_MOTOR_DECAY_TIMESCALE:
-                    m_angularMotorDecayTimescale = Math.Max(pValue, 0.01f);
+                    m_angularMotorDecayTimescale = Math.Max(0.01f, Math.Min(pValue,120));
+                    m_angularMotor.TargetValueDecayTimeScale = m_angularMotorDecayTimescale;
                     break;
                 case Vehicle.ANGULAR_MOTOR_TIMESCALE:
                     m_angularMotorTimescale = Math.Max(pValue, 0.01f);
+                    m_angularMotor.TimeScale = m_angularMotorTimescale;
                     break;
                 case Vehicle.BANKING_EFFICIENCY:
                     m_bankingEfficiency = Math.Max(-1f, Math.Min(pValue, 1f));
@@ -185,33 +189,40 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     m_linearDeflectionTimescale = Math.Max(pValue, 0.01f);
                     break;
                 case Vehicle.LINEAR_MOTOR_DECAY_TIMESCALE:
-                    m_linearMotorDecayTimescale = Math.Max(pValue, 0.01f);
+                    m_linearMotorDecayTimescale = Math.Max(0.01f, Math.Min(pValue,120));
+                    m_linearMotor.TargetValueDecayTimeScale = m_linearMotorDecayTimescale;
                     break;
                 case Vehicle.LINEAR_MOTOR_TIMESCALE:
                     m_linearMotorTimescale = Math.Max(pValue, 0.01f);
+                    m_linearMotor.TimeScale = m_linearMotorTimescale;
                     break;
                 case Vehicle.VERTICAL_ATTRACTION_EFFICIENCY:
                     m_verticalAttractionEfficiency = Math.Max(0.1f, Math.Min(pValue, 1f));
+                    m_verticalAttractionMotor.Efficiency = m_verticalAttractionEfficiency;
                     break;
                 case Vehicle.VERTICAL_ATTRACTION_TIMESCALE:
                     m_verticalAttractionTimescale = Math.Max(pValue, 0.01f);
+                    m_verticalAttractionMotor.TimeScale = m_verticalAttractionTimescale;
                     break;
 
                 // These are vector properties but the engine lets you use a single float value to
                 // set all of the components to the same value
                 case Vehicle.ANGULAR_FRICTION_TIMESCALE:
                     m_angularFrictionTimescale = new Vector3(pValue, pValue, pValue);
+                    m_angularMotor.FrictionTimescale = m_angularFrictionTimescale;
                     break;
                 case Vehicle.ANGULAR_MOTOR_DIRECTION:
                     m_angularMotorDirection = new Vector3(pValue, pValue, pValue);
-                    // m_angularMotorApply = 100;
+                    m_angularMotor.SetTarget(m_angularMotorDirection);
                     break;
                 case Vehicle.LINEAR_FRICTION_TIMESCALE:
                     m_linearFrictionTimescale = new Vector3(pValue, pValue, pValue);
+                    m_linearMotor.FrictionTimescale = m_linearFrictionTimescale;
                     break;
                 case Vehicle.LINEAR_MOTOR_DIRECTION:
                     m_linearMotorDirection = new Vector3(pValue, pValue, pValue);
                     m_linearMotorDirectionLASTSET = new Vector3(pValue, pValue, pValue);
+                    m_linearMotor.SetTarget(m_linearMotorDirection);
                     break;
                 case Vehicle.LINEAR_MOTOR_OFFSET:
                     m_linearMotorOffset = new Vector3(pValue, pValue, pValue);
@@ -227,6 +238,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             {
                 case Vehicle.ANGULAR_FRICTION_TIMESCALE:
                     m_angularFrictionTimescale = new Vector3(pValue.X, pValue.Y, pValue.Z);
+                    m_angularMotor.FrictionTimescale = m_angularFrictionTimescale;
                     break;
                 case Vehicle.ANGULAR_MOTOR_DIRECTION:
                     // Limit requested angular speed to 2 rps= 4 pi rads/sec
@@ -234,14 +246,16 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     pValue.Y = Math.Max(-12.56f, Math.Min(pValue.Y, 12.56f));
                     pValue.Z = Math.Max(-12.56f, Math.Min(pValue.Z, 12.56f));
                     m_angularMotorDirection = new Vector3(pValue.X, pValue.Y, pValue.Z);
-                    // m_angularMotorApply = 100;
+                    m_angularMotor.SetTarget(m_angularMotorDirection);
                     break;
                 case Vehicle.LINEAR_FRICTION_TIMESCALE:
                     m_linearFrictionTimescale = new Vector3(pValue.X, pValue.Y, pValue.Z);
+                    m_linearMotor.FrictionTimescale = m_linearFrictionTimescale;
                     break;
                 case Vehicle.LINEAR_MOTOR_DIRECTION:
                     m_linearMotorDirection = new Vector3(pValue.X, pValue.Y, pValue.Z);
                     m_linearMotorDirectionLASTSET = new Vector3(pValue.X, pValue.Y, pValue.Z);
+                    m_linearMotor.SetTarget(m_linearMotorDirection);
                     break;
                 case Vehicle.LINEAR_MOTOR_OFFSET:
                     m_linearMotorOffset = new Vector3(pValue.X, pValue.Y, pValue.Z);
@@ -303,7 +317,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     m_VhoverEfficiency = 0;
                     m_VhoverTimescale = 0;
                     m_VehicleBuoyancy = 0;
-                    
+
                     m_linearDeflectionEfficiency = 1;
                     m_linearDeflectionTimescale = 1;
 
@@ -319,6 +333,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
                     m_referenceFrame = Quaternion.Identity;
                     m_flags = (VehicleFlag)0;
+
                     break;
 
                 case Vehicle.TYPE_SLED:
@@ -351,10 +366,13 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     m_bankingMix = 1;
 
                     m_referenceFrame = Quaternion.Identity;
-                    m_flags |= (VehicleFlag.NO_DEFLECTION_UP | VehicleFlag.LIMIT_ROLL_ONLY | VehicleFlag.LIMIT_MOTOR_UP);
-                    m_flags &=
-                         ~(VehicleFlag.HOVER_WATER_ONLY | VehicleFlag.HOVER_TERRAIN_ONLY |
-                           VehicleFlag.HOVER_GLOBAL_HEIGHT | VehicleFlag.HOVER_UP_ONLY);
+                    m_flags &= ~(VehicleFlag.HOVER_WATER_ONLY
+                                | VehicleFlag.HOVER_TERRAIN_ONLY
+                                | VehicleFlag.HOVER_GLOBAL_HEIGHT
+                                | VehicleFlag.HOVER_UP_ONLY);
+                    m_flags |= (VehicleFlag.NO_DEFLECTION_UP
+                            | VehicleFlag.LIMIT_ROLL_ONLY
+                            | VehicleFlag.LIMIT_MOTOR_UP);
                     break;
                 case Vehicle.TYPE_CAR:
                     m_linearMotorDirection = Vector3.Zero;
@@ -427,9 +445,9 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     m_flags &= ~(VehicleFlag.HOVER_TERRAIN_ONLY
                                     | VehicleFlag.HOVER_GLOBAL_HEIGHT
                                     | VehicleFlag.LIMIT_ROLL_ONLY
+                                    | VehicleFlag.LIMIT_MOTOR_UP
                                     | VehicleFlag.HOVER_UP_ONLY);
                     m_flags |= (VehicleFlag.NO_DEFLECTION_UP
-                                    | VehicleFlag.LIMIT_MOTOR_UP
                                     | VehicleFlag.HOVER_WATER_ONLY);
                     break;
                 case Vehicle.TYPE_AIRPLANE:
@@ -510,6 +528,28 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                                     | VehicleFlag.HOVER_GLOBAL_HEIGHT);
                     break;
             }
+
+            // Update any physical parameters based on this type.
+            Refresh();
+
+            m_linearMotor = new BSVMotor("LinearMotor", m_linearMotorTimescale,
+                                m_linearMotorDecayTimescale, m_linearFrictionTimescale,
+                                1f);
+            m_linearMotor.PhysicsScene = PhysicsScene;  // DEBUG DEBUG DEBUG (enables detail logging)
+
+            m_angularMotor = new BSVMotor("AngularMotor", m_angularMotorTimescale,
+                                m_angularMotorDecayTimescale, m_angularFrictionTimescale,
+                                1f);
+            m_angularMotor.PhysicsScene = PhysicsScene;  // DEBUG DEBUG DEBUG (enables detail logging)
+
+            m_verticalAttractionMotor = new BSVMotor("VerticalAttraction", m_verticalAttractionTimescale,
+                                BSMotor.Infinite, BSMotor.InfiniteVector,
+                                m_verticalAttractionEfficiency);
+            // Z goes away and we keep X and Y
+            m_verticalAttractionMotor.FrictionTimescale = new Vector3(BSMotor.Infinite, BSMotor.Infinite, 0.1f);
+            m_verticalAttractionMotor.PhysicsScene = PhysicsScene;  // DEBUG DEBUG DEBUG (enables detail logging)
+
+            // m_bankingMotor = new BSVMotor("BankingMotor", ...);
         }
 
         // Some of the properties of this prim may have changed.
@@ -518,13 +558,25 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         {
             if (IsActive)
             {
-                // Friction effects are handled by this vehicle code
-                BulletSimAPI.SetFriction2(Prim.PhysBody.ptr, 0f);
-                BulletSimAPI.SetHitFraction2(Prim.PhysBody.ptr, 0f);
-
-                // BulletSimAPI.SetAngularDamping2(Prim.PhysBody.ptr, 0.8f);
+                m_vehicleMass = Prim.Linkset.LinksetMass;
 
-                VDetailLog("{0},BSDynamics.Refresh,zeroingFriction and adding damping", Prim.LocalID);
+                // Friction effects are handled by this vehicle code
+                float friction = 0f;
+                BulletSimAPI.SetFriction2(Prim.PhysBody.ptr, friction);
+
+                // Moderate angular movement introduced by Bullet.
+                // TODO: possibly set AngularFactor and LinearFactor for the type of vehicle.
+                //     Maybe compute linear and angular factor and damping from params.
+                float angularDamping = PhysicsScene.Params.vehicleAngularDamping;
+                BulletSimAPI.SetAngularDamping2(Prim.PhysBody.ptr, angularDamping);
+
+                // DEBUG DEBUG DEBUG: use uniform inertia to smooth movement added by Bullet
+                // Vector3 localInertia = new Vector3(1f, 1f, 1f);
+                Vector3 localInertia = new Vector3(m_vehicleMass, m_vehicleMass, m_vehicleMass);
+                BulletSimAPI.SetMassProps2(Prim.PhysBody.ptr, m_vehicleMass, localInertia);
+
+                VDetailLog("{0},BSDynamics.Refresh,frict={1},inert={2},aDamp={3}",
+                                Prim.LocalID, friction, localInertia, angularDamping);
             }
         }
 
@@ -551,111 +603,109 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         {
             if (!IsActive) return;
 
-            // DEBUG
-            // Because Bullet does apply forces to the vehicle, our last computed
-            //     linear and angular velocities are not what is happening now.
-            // Vector3 externalAngularVelocity = Prim.ForceRotationalVelocity - m_lastAngularVelocity;
-            // m_lastAngularVelocity += (externalAngularVelocity * 0.5f) * pTimestep;
-            // m_lastAngularVelocity = Prim.ForceRotationalVelocity;   // DEBUG: account for what Bullet did last time
-            // m_lastLinearVelocityVector = Prim.ForceVelocity * Quaternion.Inverse(Prim.ForceOrientation);        // DEBUG:
-            // END DEBUG
-
-            m_vehicleMass = Prim.Linkset.LinksetMass;
-
             MoveLinear(pTimestep);
-            // Commented out for debug
             MoveAngular(pTimestep);
-            // Prim.ApplyTorqueImpulse(-Prim.RotationalVelocity * m_vehicleMass, false);    // DEBUG DEBUG
-            // Prim.ForceRotationalVelocity = -Prim.RotationalVelocity;    // DEBUG DEBUG
 
             LimitRotation(pTimestep);
 
             // remember the position so next step we can limit absolute movement effects
             m_lastPositionVector = Prim.ForcePosition;
 
-            VDetailLog("{0},BSDynamics.Step,frict={1},grav={2},inertia={3},mass={4}",        // DEBUG DEBUG
-                                    Prim.LocalID, 
-                                    BulletSimAPI.GetFriction2(Prim.PhysBody.ptr),
-                                    BulletSimAPI.GetGravity2(Prim.PhysBody.ptr),
-                                    Prim.Inertia,
-                                    m_vehicleMass
-                                    );
             VDetailLog("{0},BSDynamics.Step,done,pos={1},force={2},velocity={3},angvel={4}",
                     Prim.LocalID, Prim.ForcePosition, Prim.Force, Prim.ForceVelocity, Prim.RotationalVelocity);
-        }// end Step
+        }
 
         // Apply the effect of the linear motor.
         // Also does hover and float.
         private void MoveLinear(float pTimestep)
         {
-            // m_linearMotorDirection is the target direction we are moving relative to the vehicle coordinates
-            // m_lastLinearVelocityVector is the current speed we are moving in that direction
-            if (m_linearMotorDirection.LengthSquared() > 0.001f)
-            {
-                Vector3 origDir = m_linearMotorDirection;       // DEBUG
-                Vector3 origVel = m_lastLinearVelocityVector;   // DEBUG
-                // DEBUG: the vehicle velocity rotated to be relative to vehicle coordinates for comparison
-                Vector3 vehicleVelocity = Prim.ForceVelocity * Quaternion.Inverse(Prim.ForceOrientation);   // DEBUG
+            Vector3 linearMotorContribution = m_linearMotor.Step(pTimestep);
+
+            // Rotate new object velocity from vehicle relative to world coordinates
+            linearMotorContribution *= Prim.ForceOrientation;
+
+            // ==================================================================
+            // Gravity and Buoyancy
+            // There is some gravity, make a gravity force vector that is applied after object velocity.
+            // m_VehicleBuoyancy: -1=2g; 0=1g; 1=0g;
+            Vector3 grav = Prim.PhysicsScene.DefaultGravity * (1f - m_VehicleBuoyancy);
 
-                // Add (desiredVelocity - lastAppliedVelocity) / howLongItShouldTakeToComplete
-                Vector3 addAmount = (m_linearMotorDirection - m_lastLinearVelocityVector)/(m_linearMotorTimescale) * pTimestep;
-                m_lastLinearVelocityVector += addAmount;
+            Vector3 pos = Prim.ForcePosition;
+            float terrainHeight = Prim.PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(pos);
 
-                float decayFactor = (1.0f / m_linearMotorDecayTimescale) * pTimestep;
-                m_linearMotorDirection *= (1f - decayFactor);
+            Vector3 terrainHeightContribution = ComputeLinearTerrainHeightCorrection(pTimestep, ref pos, terrainHeight);
 
-                // Rotate new object velocity from vehicle relative to world coordinates
-                m_newVelocity = m_lastLinearVelocityVector * Prim.ForceOrientation;
+            Vector3 hoverContribution = ComputeLinearHover(pTimestep, ref pos, terrainHeight);
 
-                // Apply friction for next time
-                Vector3 frictionFactor = (Vector3.One / m_linearFrictionTimescale) * pTimestep;
-                m_lastLinearVelocityVector *= (Vector3.One - frictionFactor);
+            ComputeLinearBlockingEndPoint(pTimestep, ref pos);
 
-                VDetailLog("{0},MoveLinear,nonZero,origlmDir={1},origlvVel={2},vehVel={3},add={4},decay={5},frict={6},lmDir={7},lvVec={8},newVel={9}",
-                                Prim.LocalID, origDir, origVel, vehicleVelocity, addAmount, decayFactor, frictionFactor, 
-                                m_linearMotorDirection, m_lastLinearVelocityVector, m_newVelocity);
-            }
-            else
-            {
-                // if what remains of direction is very small, zero it.
-                m_linearMotorDirection = Vector3.Zero;
-                m_lastLinearVelocityVector = Vector3.Zero;
-                m_newVelocity = Vector3.Zero;
+            Vector3 limitMotorUpContribution = ComputeLinearMotorUp(pTimestep, pos, terrainHeight);
+
+            // ==================================================================
+            Vector3 newVelocity = linearMotorContribution
+                            + terrainHeightContribution
+                            + hoverContribution
+                            + limitMotorUpContribution;
 
-                VDetailLog("{0},MoveLinear,zeroed", Prim.LocalID);
+            // If not changing some axis, reduce out velocity
+            if ((m_flags & (VehicleFlag.NO_X)) != 0)
+                newVelocity.X = 0;
+            if ((m_flags & (VehicleFlag.NO_Y)) != 0)
+                newVelocity.Y = 0;
+            if ((m_flags & (VehicleFlag.NO_Z)) != 0)
+                newVelocity.Z = 0;
+
+            // ==================================================================
+            // Clamp REALLY high or low velocities
+            float newVelocityLengthSq = newVelocity.LengthSquared();
+            if (newVelocityLengthSq > 1e6f)
+            {
+                newVelocity /= newVelocity.Length();
+                newVelocity *= 1000f;
             }
+            else if (newVelocityLengthSq < 1e-6f)
+                newVelocity = Vector3.Zero;
 
-            // m_newVelocity is velocity computed from linear motor in world coordinates
+            // ==================================================================
+            // Stuff new linear velocity into the vehicle
+            Prim.ForceVelocity = newVelocity;
+            // Prim.ApplyForceImpulse((m_newVelocity - Prim.Velocity) * m_vehicleMass, false);    // DEBUG DEBUG
 
-            // Gravity and Buoyancy
-            // There is some gravity, make a gravity force vector that is applied after object velocity.
-            // m_VehicleBuoyancy: -1=2g; 0=1g; 1=0g;
-            Vector3 grav = Prim.PhysicsScene.DefaultGravity * (1f - m_VehicleBuoyancy);
+            // Other linear forces are applied as forces.
+            Vector3 totalDownForce = grav * m_vehicleMass;
+            if (totalDownForce != Vector3.Zero)
+            {
+                Prim.AddForce(totalDownForce, false);
+            }
 
-            /*
-             * RA: Not sure why one would do this unless we are hoping external forces are doing gravity, ...
-            // Preserve the current Z velocity
-            Vector3 vel_now = m_prim.Velocity;
-            m_dir.Z = vel_now.Z;        // Preserve the accumulated falling velocity
-             */
+            VDetailLog("{0},MoveLinear,done,lmDir={1},lmVel={2},newVel={3},primVel={4},totalDown={5}",
+                                Prim.LocalID, m_linearMotorDirection, m_lastLinearVelocityVector,
+                                newVelocity, Prim.Velocity, totalDownForce);
 
-            Vector3 pos = Prim.ForcePosition;
-//            Vector3 accel = new Vector3(-(m_dir.X - m_lastLinearVelocityVector.X / 0.1f), -(m_dir.Y - m_lastLinearVelocityVector.Y / 0.1f), m_dir.Z - m_lastLinearVelocityVector.Z / 0.1f);
+        } // end MoveLinear()
 
+        public Vector3 ComputeLinearTerrainHeightCorrection(float pTimestep, ref Vector3 pos, float terrainHeight)
+        {
+            Vector3 ret = Vector3.Zero;
             // If below the terrain, move us above the ground a little.
-            float terrainHeight = Prim.PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(pos);
             // Taking the rotated size doesn't work here because m_prim.Size is the size of the root prim and not the linkset.
             //     TODO: Add a m_prim.LinkSet.Size similar to m_prim.LinkSet.Mass.
             // Vector3 rotatedSize = m_prim.Size * m_prim.ForceOrientation;
             // if (rotatedSize.Z < terrainHeight)
             if (pos.Z < terrainHeight)
             {
+                // TODO: correct position by applying force rather than forcing position.
                 pos.Z = terrainHeight + 2;
                 Prim.ForcePosition = pos;
                 VDetailLog("{0},MoveLinear,terrainHeight,terrainHeight={1},pos={2}", Prim.LocalID, terrainHeight, pos);
             }
+            return ret;
+        }
+
+        public Vector3 ComputeLinearHover(float pTimestep, ref Vector3 pos, float terrainHeight)
+        {
+            Vector3 ret = Vector3.Zero;
 
-            // Check if hovering
             // m_VhoverEfficiency: 0=bouncy, 1=totally damped
             // m_VhoverTimescale: time to achieve height
             if ((m_flags & (VehicleFlag.HOVER_WATER_ONLY | VehicleFlag.HOVER_TERRAIN_ONLY | VehicleFlag.HOVER_GLOBAL_HEIGHT)) != 0)
@@ -663,7 +713,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 // We should hover, get the target height
                 if ((m_flags & VehicleFlag.HOVER_WATER_ONLY) != 0)
                 {
-                    m_VhoverTargetHeight = Prim.PhysicsScene.GetWaterLevelAtXYZ(pos) + m_VhoverHeight;
+                    m_VhoverTargetHeight = Prim.PhysicsScene.TerrainManager.GetWaterLevelAtXYZ(pos) + m_VhoverHeight;
                 }
                 if ((m_flags & VehicleFlag.HOVER_TERRAIN_ONLY) != 0)
                 {
@@ -680,6 +730,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     if (pos.Z > m_VhoverTargetHeight)
                         m_VhoverTargetHeight = pos.Z;
                 }
+                
                 if ((m_flags & VehicleFlag.LOCK_HOVER_HEIGHT) != 0)
                 {
                     if (Math.Abs(pos.Z - m_VhoverTargetHeight) > 0.2f)
@@ -694,28 +745,31 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     // RA: where does the 50 come from?
                     float verticalCorrectionVelocity = pTimestep * ((verticalError * 50.0f) / m_VhoverTimescale);
                     // Replace Vertical speed with correction figure if significant
-                    if (Math.Abs(verticalError) > 0.01f)
+                    if (verticalError > 0.01f)
                     {
-                        m_newVelocity.Z += verticalCorrectionVelocity;
+                        ret = new Vector3(0f, 0f, verticalCorrectionVelocity);
                         //KF: m_VhoverEfficiency is not yet implemented
                     }
                     else if (verticalError < -0.01)
                     {
-                        m_newVelocity.Z -= verticalCorrectionVelocity;
-                    }
-                    else
-                    {
-                        m_newVelocity.Z = 0f;
+                        ret = new Vector3(0f, 0f, -verticalCorrectionVelocity);
                     }
                 }
 
-                VDetailLog("{0},MoveLinear,hover,pos={1},dir={2},height={3},target={4}", Prim.LocalID, pos, m_newVelocity, m_VhoverHeight, m_VhoverTargetHeight);
+                VDetailLog("{0},MoveLinear,hover,pos={1},dir={2},height={3},target={4}",
+                                Prim.LocalID, pos, ret, m_VhoverHeight, m_VhoverTargetHeight);
             }
 
+            return ret;
+        }
+
+        public bool ComputeLinearBlockingEndPoint(float pTimestep, ref Vector3 pos)
+        {
+            bool changed = false;
+
             Vector3 posChange = pos - m_lastPositionVector;
             if (m_BlockingEndPoint != Vector3.Zero)
             {
-                bool changed = false;
                 if (pos.X >= (m_BlockingEndPoint.X - (float)1))
                 {
                     pos.X -= posChange.X + 1;
@@ -748,75 +802,53 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                                 Prim.LocalID, m_BlockingEndPoint, posChange, pos);
                 }
             }
+            return changed;
+        }
 
-            #region downForce
-            Vector3 downForce = Vector3.Zero;
-
+        // From http://wiki.secondlife.com/wiki/LlSetVehicleFlags :
+        //    Prevent ground vehicles from motoring into the sky.This flag has a subtle effect when
+        //    used with conjunction with banking: the strength of the banking will decay when the
+        //    vehicle no longer experiences collisions. The decay timescale is the same as
+        //    VEHICLE_BANKING_TIMESCALE. This is to help prevent ground vehicles from steering
+        //    when they are in mid jump. 
+        // TODO: this code is wrong. Also, what should it do for boats?
+        public Vector3 ComputeLinearMotorUp(float pTimestep, Vector3 pos, float terrainHeight)
+        {
+            Vector3 ret = Vector3.Zero;
             if ((m_flags & (VehicleFlag.LIMIT_MOTOR_UP)) != 0)
             {
                 // If the vehicle is motoring into the sky, get it going back down.
-                // Is this an angular force or both linear and angular??
                 float distanceAboveGround = pos.Z - terrainHeight;
-                if (distanceAboveGround > 2f)
+                if (distanceAboveGround > 1f)
                 {
                     // downForce = new Vector3(0, 0, (-distanceAboveGround / m_bankingTimescale) * pTimestep);
                     // downForce = new Vector3(0, 0, -distanceAboveGround / m_bankingTimescale);
-                    downForce = new Vector3(0, 0, -distanceAboveGround);
+                    ret = new Vector3(0, 0, -distanceAboveGround);
                 }
-                // TODO: this calculation is all wrong. From the description at
+                // TODO: this calculation is wrong. From the description at
                 //     (http://wiki.secondlife.com/wiki/Category:LSL_Vehicle), the downForce
                 //     has a decay factor. This says this force should
                 //     be computed with a motor.
-                VDetailLog("{0},MoveLinear,limitMotorUp,distAbove={1},downForce={2}", 
-                                    Prim.LocalID, distanceAboveGround, downForce);
-            }
-            #endregion // downForce
-
-            // If not changing some axis, reduce out velocity
-            if ((m_flags & (VehicleFlag.NO_X)) != 0)
-                m_newVelocity.X = 0;
-            if ((m_flags & (VehicleFlag.NO_Y)) != 0)
-                m_newVelocity.Y = 0;
-            if ((m_flags & (VehicleFlag.NO_Z)) != 0)
-                m_newVelocity.Z = 0;
-
-            // Clamp REALLY high or low velocities
-            if (m_newVelocity.LengthSquared() > 1e6f)
-            {
-                m_newVelocity /= m_newVelocity.Length();
-                m_newVelocity *= 1000f;
-            }
-            else if (m_newVelocity.LengthSquared() < 1e-6f)
-                m_newVelocity = Vector3.Zero;
-
-            // Stuff new linear velocity into the vehicle
-            Prim.ForceVelocity = m_newVelocity;
-            // Prim.ApplyForceImpulse((m_newVelocity - Prim.Velocity) * m_vehicleMass, false);    // DEBUG DEBUG
-
-            Vector3 totalDownForce = downForce + grav;
-            if (totalDownForce != Vector3.Zero)
-            {
-                Prim.AddForce(totalDownForce * m_vehicleMass, false);
-                // Prim.ApplyForceImpulse(totalDownForce * m_vehicleMass, false);
+                // TODO: add interaction with banking.
+                VDetailLog("{0},MoveLinear,limitMotorUp,distAbove={1},downForce={2}",
+                                    Prim.LocalID, distanceAboveGround, ret);
             }
+            return ret;
+        }
 
-            VDetailLog("{0},MoveLinear,done,lmDir={1},lmVel={2},newVel={3},primVel={4},totalDown={5}",
-                    Prim.LocalID, m_linearMotorDirection, m_lastLinearVelocityVector, m_newVelocity, Prim.Velocity, totalDownForce);
-
-        } // end MoveLinear()
-
+        // =======================================================================
         // =======================================================================
         // Apply the effect of the angular motor.
         private void MoveAngular(float pTimestep)
         {
             // m_angularMotorDirection         // angular velocity requested by LSL motor
-            // m_angularMotorApply             // application frame counter
             // m_angularMotorVelocity          // current angular motor velocity (ramps up and down)
-            // m_angularMotorTimescale         // motor angular velocity ramp up rate
+            // m_angularMotorTimescale         // motor angular velocity ramp up time
             // m_angularMotorDecayTimescale    // motor angular velocity decay rate
             // m_angularFrictionTimescale      // body angular velocity  decay rate
             // m_lastAngularVelocity           // what was last applied to body
 
+            /*
             if (m_angularMotorDirection.LengthSquared() > 0.0001)
             {
                 Vector3 origVel = m_angularMotorVelocity;
@@ -835,59 +867,157 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             {
                 m_angularMotorVelocity = Vector3.Zero;
             }
+            */
 
-            #region Vertical attactor
+            Vector3 angularMotorContribution = m_angularMotor.Step(pTimestep);
 
-            Vector3 vertattr = Vector3.Zero;
-            Vector3 deflection = Vector3.Zero;
-            Vector3 banking = Vector3.Zero;
+            // ==================================================================
+            // From http://wiki.secondlife.com/wiki/LlSetVehicleFlags :
+            //    This flag prevents linear deflection parallel to world z-axis. This is useful
+            //    for preventing ground vehicles with large linear deflection, like bumper cars,
+            //    from climbing their linear deflection into the sky. 
+            // That is, NO_DEFLECTION_UP says angular motion should not add any pitch or roll movement
+            if ((m_flags & (VehicleFlag.NO_DEFLECTION_UP)) != 0)
+            {
+                angularMotorContribution.X = 0f;
+                angularMotorContribution.Y = 0f;
+                VDetailLog("{0},MoveAngular,noDeflectionUp,angularMotorContrib={1}", Prim.LocalID, angularMotorContribution);
+            }
 
-            // If vertical attaction timescale is reasonable and we applied an angular force last time...
-            if (m_verticalAttractionTimescale < 300 && m_lastAngularVelocity != Vector3.Zero)
+            Vector3 verticalAttractionContribution = ComputeAngularVerticalAttraction(pTimestep);
+
+            Vector3 deflectionContribution = ComputeAngularDeflection(pTimestep);
+
+            Vector3 bankingContribution = ComputeAngularBanking(pTimestep);
+
+            // ==================================================================
+            m_lastVertAttractor = verticalAttractionContribution;
+
+            // Sum velocities
+            m_lastAngularVelocity = angularMotorContribution
+                                    + verticalAttractionContribution
+                                    + deflectionContribution
+                                    + bankingContribution;
+
+            // ==================================================================
+            //Offset section
+            if (m_linearMotorOffset != Vector3.Zero)
+            {
+                //Offset of linear velocity doesn't change the linear velocity,
+                //   but causes a torque to be applied, for example...
+                //
+                //      IIIII     >>>   IIIII
+                //      IIIII     >>>    IIIII
+                //      IIIII     >>>     IIIII
+                //          ^
+                //          |  Applying a force at the arrow will cause the object to move forward, but also rotate
+                //
+                //
+                // The torque created is the linear velocity crossed with the offset
+
+                // TODO: this computation should be in the linear section
+                //    because that is where we know the impulse being applied.
+                Vector3 torqueFromOffset = Vector3.Zero;
+                // torqueFromOffset = Vector3.Cross(m_linearMotorOffset, appliedImpulse);
+                if (float.IsNaN(torqueFromOffset.X))
+                    torqueFromOffset.X = 0;
+                if (float.IsNaN(torqueFromOffset.Y))
+                    torqueFromOffset.Y = 0;
+                if (float.IsNaN(torqueFromOffset.Z))
+                    torqueFromOffset.Z = 0;
+                torqueFromOffset *= m_vehicleMass;
+                Prim.ApplyTorqueImpulse(torqueFromOffset, true);
+                VDetailLog("{0},BSDynamic.MoveAngular,motorOffset,applyTorqueImpulse={1}", Prim.LocalID, torqueFromOffset);
+            }
+
+            // ==================================================================
+            if (m_lastAngularVelocity.ApproxEquals(Vector3.Zero, 0.01f))
+            {
+                m_lastAngularVelocity = Vector3.Zero; // Reduce small value to zero.
+                // TODO: zeroing is good but it also sets values in unmanaged code. Remove the stores when idle.
+                VDetailLog("{0},MoveAngular,zeroAngularMotion,lastAngular={1}", Prim.LocalID, m_lastAngularVelocity);
+                Prim.ZeroAngularMotion(true);
+            }
+            else
             {
-                float VAservo = pTimestep * 0.2f / m_verticalAttractionTimescale;
-                if (Prim.IsColliding)
-                    VAservo = pTimestep * 0.05f / (m_verticalAttractionTimescale);
+                // Apply to the body.
+                // The above calculates the absolute angular velocity needed. Angular velocity is massless.
+                // Since we are stuffing the angular velocity directly into the object, the computed
+                //     velocity needs to be scaled by the timestep.
+                // Also remove any motion that is on the object so added motion is only from vehicle.
+                Vector3 applyAngularForce = ((m_lastAngularVelocity * pTimestep)
+                                                - Prim.ForceRotationalVelocity);
+                // Unscale the force by the angular factor so it overwhelmes the Bullet additions.
+                Prim.ForceRotationalVelocity = applyAngularForce;
+
+                VDetailLog("{0},MoveAngular,done,angMotor={1},vertAttr={2},bank={3},deflect={4},newAngForce={5},lastAngular={6}",
+                                    Prim.LocalID,
+                                    angularMotorContribution, verticalAttractionContribution,
+                                    bankingContribution, deflectionContribution,
+                                    applyAngularForce, m_lastAngularVelocity
+                                    );
+            }
+        }
 
-                VAservo *= (m_verticalAttractionEfficiency * m_verticalAttractionEfficiency);
+        public Vector3 ComputeAngularVerticalAttraction(float pTimestep)
+        {
+            Vector3 ret = Vector3.Zero;
 
-                // Create a vector of the vehicle "up" in world coordinates
+            // If vertical attaction timescale is reasonable and we applied an angular force last time...
+            if (m_verticalAttractionTimescale < 500)
+            {
+                Vector3 verticalError = Vector3.UnitZ * Prim.ForceOrientation;
+                verticalError.Normalize();
+                m_verticalAttractionMotor.SetCurrent(verticalError);
+                m_verticalAttractionMotor.SetTarget(Vector3.UnitZ);
+                ret = m_verticalAttractionMotor.Step(pTimestep);
+                /*
+                // Take a vector pointing up and convert it from world to vehicle relative coords.
                 Vector3 verticalError = Vector3.UnitZ * Prim.ForceOrientation;
-                // verticalError.X and .Y are the World error amounts. They are 0 when there is no
-                //      error (Vehicle Body is 'vertical'), and .Z will be 1. As the body leans to its
-                //      side |.X| will increase to 1 and .Z fall to 0. As body inverts |.X| will fall
-                //      and .Z will go // negative. Similar for tilt and |.Y|. .X and .Y must be
-                //      modulated to prevent a stable inverted body.
-
-                // Error is 0 (no error) to +/- 2 (max error)
-                if (verticalError.Z < 0.0f)
+                verticalError.Normalize();
+
+                // If vertical attraction correction is needed, the vector that was pointing up (UnitZ)
+                //    is now leaning to one side (rotated around the X axis) and the Y value will
+                //    go from zero (nearly straight up) to one (completely to the side) or leaning
+                //    front-to-back (rotated around the Y axis) and the value of X will be between
+                //    zero and one.
+                // The value of Z is how far the rotation is off with 1 meaning none and 0 being 90 degrees.
+
+                // If verticalError.Z is negative, the vehicle is upside down. Add additional push.
+                if (verticalError.Z < 0f)
                 {
-                    verticalError.X = 2.0f - verticalError.X;
-                    verticalError.Y = 2.0f - verticalError.Y;
+                    verticalError.X = 2f - verticalError.X;
+                    verticalError.Y = 2f - verticalError.Y;
                 }
-                // scale it by VAservo (timestep and timescale)
-                verticalError = verticalError * VAservo;
 
-                // As the body rotates around the X axis, then verticalError.Y increases; Rotated around Y
-                //     then .X increases, so change  Body angular velocity  X based on Y, and Y based on X.
-                //     Z is not changed.
-                vertattr.X =    verticalError.Y;
-                vertattr.Y =  - verticalError.X;
-                vertattr.Z = 0f;
+                // Y error means needed rotation around X axis and visa versa.
+                verticalAttractionContribution.X =    verticalError.Y;
+                verticalAttractionContribution.Y =  - verticalError.X;
+                verticalAttractionContribution.Z = 0f;
 
-                // scaling appears better usingsquare-law
-                Vector3 angularVelocity = Prim.ForceRotationalVelocity;
-                float bounce = 1.0f - (m_verticalAttractionEfficiency * m_verticalAttractionEfficiency);
-                vertattr.X += bounce * angularVelocity.X;
-                vertattr.Y += bounce * angularVelocity.Y;
+                // scale by the time scale and timestep
+                Vector3 unscaledContrib = verticalAttractionContribution;
+                verticalAttractionContribution /= m_verticalAttractionTimescale;
+                verticalAttractionContribution *= pTimestep;
 
-                VDetailLog("{0},MoveAngular,verticalAttraction,VAservo={1},effic={2},verticalError={3},bounce={4},vertattr={5}",
-                            Prim.LocalID, VAservo, m_verticalAttractionEfficiency, verticalError, bounce, vertattr);
+                // apply efficiency
+                Vector3 preEfficiencyContrib = verticalAttractionContribution;
+                float efficencySquared = m_verticalAttractionEfficiency * m_verticalAttractionEfficiency;
+                verticalAttractionContribution *= (m_verticalAttractionEfficiency * m_verticalAttractionEfficiency);
+
+                VDetailLog("{0},MoveAngular,verticalAttraction,,verticalError={1},unscaled={2},preEff={3},eff={4},effSq={5},vertAttr={6}",
+                                            Prim.LocalID, verticalError, unscaledContrib, preEfficiencyContrib,
+                                            m_verticalAttractionEfficiency, efficencySquared,
+                                            verticalAttractionContribution);
+                 */
 
             }
-            #endregion // Vertical attactor
+            return ret;
+        }
 
-            #region Deflection
+        public Vector3 ComputeAngularDeflection(float pTimestep)
+        {
+            Vector3 ret = Vector3.Zero;
 
             if (m_angularDeflectionEfficiency != 0)
             {
@@ -899,32 +1029,35 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 Vector3 preferredAxisOfMotion = scaledDefaultDirection * Quaternion.Add(Prim.ForceOrientation, m_referenceFrame);
 
                 // Scale by efficiency and timescale
-                deflection = (preferredAxisOfMotion * (m_angularDeflectionEfficiency) / m_angularDeflectionTimescale) * pTimestep;
+                ret = (preferredAxisOfMotion * (m_angularDeflectionEfficiency) / m_angularDeflectionTimescale) * pTimestep;
+
+                VDetailLog("{0},MoveAngular,Deflection,perfAxis={1},deflection={2}", Prim.LocalID, preferredAxisOfMotion, ret);
 
-                VDetailLog("{0},MoveAngular,Deflection,perfAxis={1},deflection={2}", 
-                                        Prim.LocalID, preferredAxisOfMotion, deflection);
                 // This deflection computation is not correct.
-                deflection = Vector3.Zero;
+                ret = Vector3.Zero;
             }
+            return ret;
+        }
 
-            #endregion
-
-            #region Banking
+        public Vector3 ComputeAngularBanking(float pTimestep)
+        {
+            Vector3 ret = Vector3.Zero;
 
             if (m_bankingEfficiency != 0)
             {
                 Vector3 dir = Vector3.One * Prim.ForceOrientation;
-                float mult = (m_bankingMix*m_bankingMix)*-1*(m_bankingMix < 0 ? -1 : 1);
-                    //Changes which way it banks in and out of turns
+                float mult = (m_bankingMix * m_bankingMix) * -1 * (m_bankingMix < 0 ? -1 : 1);
+                //Changes which way it banks in and out of turns
 
                 //Use the square of the efficiency, as it looks much more how SL banking works
-                float effSquared = (m_bankingEfficiency*m_bankingEfficiency);
+                float effSquared = (m_bankingEfficiency * m_bankingEfficiency);
                 if (m_bankingEfficiency < 0)
                     effSquared *= -1; //Keep the negative!
 
                 float mix = Math.Abs(m_bankingMix);
                 if (m_angularMotorVelocity.X == 0)
                 {
+                    // The vehicle is stopped
                     /*if (!parent.Orientation.ApproxEquals(this.m_referenceFrame, 0.25f))
                     {
                         Vector3 axisAngle;
@@ -938,101 +1071,39 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     }*/
                 }
                 else
-                    banking.Z += (effSquared*(mult*mix))*(m_angularMotorVelocity.X) * 4;
+                {
+                    ret.Z += (effSquared * (mult * mix)) * (m_angularMotorVelocity.X) * 4;
+                }
+
+                //If they are colliding, we probably shouldn't shove the prim around... probably
                 if (!Prim.IsColliding && Math.Abs(m_angularMotorVelocity.X) > mix)
-                    //If they are colliding, we probably shouldn't shove the prim around... probably
                 {
-                    float angVelZ = m_angularMotorVelocity.X*-1;
+                    float angVelZ = m_angularMotorVelocity.X * -1;
                     /*if(angVelZ > mix)
                         angVelZ = mix;
                     else if(angVelZ < -mix)
                         angVelZ = -mix;*/
                     //This controls how fast and how far the banking occurs
-                    Vector3 bankingRot = new Vector3(angVelZ*(effSquared*mult), 0, 0);
+                    Vector3 bankingRot = new Vector3(angVelZ * (effSquared * mult), 0, 0);
                     if (bankingRot.X > 3)
                         bankingRot.X = 3;
                     else if (bankingRot.X < -3)
                         bankingRot.X = -3;
                     bankingRot *= Prim.ForceOrientation;
-                    banking += bankingRot;
+                    ret += bankingRot;
                 }
                 m_angularMotorVelocity.X *= m_bankingEfficiency == 1 ? 0.0f : 1 - m_bankingEfficiency;
-                VDetailLog("{0},MoveAngular,Banking,bEff={1},angMotVel={2},banking={3}", 
-                                Prim.LocalID, m_bankingEfficiency, m_angularMotorVelocity, banking);
-            }
-
-            #endregion
-
-            m_lastVertAttractor = vertattr;
-
-            // Sum velocities
-            m_lastAngularVelocity = m_angularMotorVelocity + vertattr + banking + deflection;
-
-            #region Linear Motor Offset
-
-            //Offset section
-            if (m_linearMotorOffset != Vector3.Zero)
-            {
-                //Offset of linear velocity doesn't change the linear velocity,
-                //   but causes a torque to be applied, for example...
-                //
-                //      IIIII     >>>   IIIII
-                //      IIIII     >>>    IIIII
-                //      IIIII     >>>     IIIII
-                //          ^
-                //          |  Applying a force at the arrow will cause the object to move forward, but also rotate
-                //
-                //
-                // The torque created is the linear velocity crossed with the offset
-
-                // NOTE: this computation does should be in the linear section
-                //    because there we know the impulse being applied.
-                Vector3 torqueFromOffset = Vector3.Zero;
-                // torqueFromOffset = Vector3.Cross(m_linearMotorOffset, appliedImpulse);
-                if (float.IsNaN(torqueFromOffset.X))
-                    torqueFromOffset.X = 0;
-                if (float.IsNaN(torqueFromOffset.Y))
-                    torqueFromOffset.Y = 0;
-                if (float.IsNaN(torqueFromOffset.Z))
-                    torqueFromOffset.Z = 0;
-                torqueFromOffset *= m_vehicleMass;
-                Prim.ApplyTorqueImpulse(torqueFromOffset, true);
-                VDetailLog("{0},BSDynamic.MoveAngular,motorOffset,applyTorqueImpulse={1}", Prim.LocalID, torqueFromOffset);
-            }
-
-            #endregion
-
-            if ((m_flags & (VehicleFlag.NO_DEFLECTION_UP)) != 0)
-            {
-                m_lastAngularVelocity.X = 0;
-                m_lastAngularVelocity.Y = 0;
-                VDetailLog("{0},MoveAngular,noDeflectionUp,lastAngular={1}", Prim.LocalID, m_lastAngularVelocity);
+                VDetailLog("{0},MoveAngular,Banking,bEff={1},angMotVel={2},effSq={3},mult={4},mix={5},banking={6}",
+                                Prim.LocalID, m_bankingEfficiency, m_angularMotorVelocity, effSquared, mult, mix, ret);
             }
+            return ret;
+        }
 
-            if (m_lastAngularVelocity.ApproxEquals(Vector3.Zero, 0.01f))
-            {
-                m_lastAngularVelocity = Vector3.Zero; // Reduce small value to zero.
-                Prim.ZeroAngularMotion(true);
-                VDetailLog("{0},MoveAngular,zeroAngularMotion,lastAngular={1}", Prim.LocalID, m_lastAngularVelocity);
-            }
-            else
-            {
-                // Apply to the body.
-                // The above calculates the absolute angular velocity needed. Angular velocity is massless.
-                // Since we are stuffing the angular velocity directly into the object, the computed
-                //     velocity needs to be scaled by the timestep.
-                Vector3 applyAngularForce = ((m_lastAngularVelocity * pTimestep) - Prim.ForceRotationalVelocity);
-                Prim.ForceRotationalVelocity = applyAngularForce;
-
-                // Decay the angular movement for next time
-                Vector3 decayamount = (Vector3.One / m_angularFrictionTimescale) * pTimestep;
-                m_lastAngularVelocity *= Vector3.One - decayamount;
-
-                VDetailLog("{0},MoveAngular,done,newRotVel={1},decay={2},lastAngular={3}", 
-                                    Prim.LocalID, applyAngularForce, decayamount, m_lastAngularVelocity);
-            }
-        } //end MoveAngular
 
+        // This is from previous instantiations of XXXDynamics.cs.
+        // Applies roll reference frame.
+        // TODO: is this the right way to separate the code to do this operation?
+        //    Should this be in MoveAngular()?
         internal void LimitRotation(float timestep)
         {
             Quaternion rotq = Prim.ForceOrientation;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs b/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs
new file mode 100755
index 0000000..663b6f4
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs
@@ -0,0 +1,191 @@
+/*

+ * Copyright (c) Contributors, http://opensimulator.org/

+ * See CONTRIBUTORS.TXT for a full list of copyright holders.

+ *

+ * Redistribution and use in source and binary forms, with or without

+ * modification, are permitted provided that the following conditions are met:

+ *     * Redistributions of source code must retain the above copyright

+ *       notice, this list of conditions and the following disclaimer.

+ *     * Redistributions in binary form must reproduce the above copyrightD

+ *       notice, this list of conditions and the following disclaimer in the

+ *       documentation and/or other materials provided with the distribution.

+ *     * Neither the name of the OpenSimulator Project nor the

+ *       names of its contributors may be used to endorse or promote products

+ *       derived from this software without specific prior written permission.

+ *

+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY

+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY

+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

+ */

+using System;

+using System.Collections.Generic;

+using System.Text;

+using System.Reflection;

+using Nini.Config;

+

+namespace OpenSim.Region.Physics.BulletSPlugin

+{

+

+public struct MaterialAttributes

+{

+    // Material type values that correspond with definitions for LSL

+    public enum Material : int

+    {

+        Stone = 0,

+        Metal,

+        Glass,

+        Wood,

+        Flesh,

+        Plastic,

+        Rubber,

+        Light,

+        // Hereafter are BulletSim additions

+        Avatar,

+        NumberOfTypes   // the count of types in the enum.

+    }

+    // Names must be in the order of the above enum.

+    public static string[] MaterialNames = { "Stone", "Metal", "Glass", "Wood", 

+                                     "Flesh", "Plastic", "Rubber", "Light", "Avatar" };

+    public static string[] MaterialAttribs = { "Density", "Friction", "Restitution", 

+                                   "ccdMotionThreshold", "ccdSweptSphereRadius" };

+

+    public MaterialAttributes(string t, float d, float f, float r, float ccdM, float ccdS)

+    {

+        type = t;

+        density = d;

+        friction = f;

+        restitution = r;

+        ccdMotionThreshold = ccdM;

+        ccdSweptSphereRadius = ccdS;

+    }

+    public string type;

+    public float density;

+    public float friction;

+    public float restitution;

+    public float ccdMotionThreshold;

+    public float ccdSweptSphereRadius;

+}

+

+public static class BSMaterials

+{

+    public static MaterialAttributes[] Attributes;

+

+    static BSMaterials()

+    {

+        // Attribute sets for both the non-physical and physical instances of materials.

+        Attributes = new MaterialAttributes[(int)MaterialAttributes.Material.NumberOfTypes * 2];

+    }

+

+    // This is where all the default material attributes are defined.

+    public static void InitializeFromDefaults(ConfigurationParameters parms)

+    {

+    // public static string[] MaterialNames = { "Stone", "Metal", "Glass", "Wood", 

+      //                                "Flesh", "Plastic", "Rubber", "Light", "Avatar" };

+        float dFriction = parms.defaultFriction;

+        float dRestitution = parms.defaultRestitution;

+        float dDensity = parms.defaultDensity;

+        float dCcdM = parms.ccdMotionThreshold;

+        float dCcdS = parms.ccdSweptSphereRadius;

+        Attributes[(int)MaterialAttributes.Material.Stone] =

+            new MaterialAttributes("stone",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Metal] =

+            new MaterialAttributes("metal",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Glass] =

+            new MaterialAttributes("glass",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Wood] =

+            new MaterialAttributes("wood",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Flesh] =

+            new MaterialAttributes("flesh",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Plastic] =

+            new MaterialAttributes("plastic",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Rubber] =

+            new MaterialAttributes("rubber",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Light] =

+            new MaterialAttributes("light",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Avatar] =

+            new MaterialAttributes("avatar",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+

+        Attributes[(int)MaterialAttributes.Material.Stone + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("stonePhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Metal + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("metalPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Glass + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("glassPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Wood + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("woodPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Flesh + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("fleshPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Plastic + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("plasticPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Rubber + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("rubberPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Light + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("lightPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+        Attributes[(int)MaterialAttributes.Material.Avatar + (int)MaterialAttributes.Material.NumberOfTypes] =

+            new MaterialAttributes("avatarPhysical",dDensity,dFriction,dRestitution, dCcdM, dCcdS);

+    }

+

+    // Under the [BulletSim] section, one can change the individual material

+    //    attribute values. The format of the configuration parameter is:

+    //        <materialName><Attribute>["Physical"] = floatValue

+    //    For instance:

+    //        [BulletSim]

+    //             StoneFriction = 0.2

+    //             FleshRestitutionPhysical = 0.8

+    // Materials can have different parameters for their static and

+    //    physical instantiations. When setting the non-physical value,

+    //    both values are changed. Setting the physical value only changes

+    //    the physical value.

+    public static void InitializefromParameters(IConfig pConfig)

+    {

+        int matType = 0;

+        foreach (string matName in MaterialAttributes.MaterialNames)

+        {

+            foreach (string attribName in MaterialAttributes.MaterialAttribs)

+            {

+                string paramName = matName + attribName;

+                if (pConfig.Contains(paramName))

+                {

+                    float paramValue = pConfig.GetFloat(paramName);

+                    SetAttributeValue(matType, attribName, paramValue);

+                    // set the physical value also

+                    SetAttributeValue(matType + (int)MaterialAttributes.Material.NumberOfTypes, attribName, paramValue);

+                }

+                paramName += "Physical";

+                if (pConfig.Contains(paramName))

+                {

+                    float paramValue = pConfig.GetFloat(paramName);

+                    SetAttributeValue(matType + (int)MaterialAttributes.Material.NumberOfTypes, attribName, paramValue);

+                }

+            }

+            matType++;

+        }

+    }

+

+    private static void SetAttributeValue(int matType, string attribName, float val)

+    {

+        MaterialAttributes thisAttrib = Attributes[matType];

+        FieldInfo fieldInfo = thisAttrib.GetType().GetField(attribName);

+        if (fieldInfo != null)

+        {

+            fieldInfo.SetValue(thisAttrib, val);

+            Attributes[matType] = thisAttrib;

+        }

+    }

+

+    public static MaterialAttributes GetAttributes(MaterialAttributes.Material type, bool isPhysical)

+    {

+        int ind = (int)type;

+        if (isPhysical) ind += (int)MaterialAttributes.Material.NumberOfTypes;

+        return Attributes[ind];

+    }

+

+}

+}

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSMotors.cs b/OpenSim/Region/Physics/BulletSPlugin/BSMotors.cs
index bc6e4c4..e91bfa8 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSMotors.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSMotors.cs
@@ -1,104 +1,169 @@
-using System;

-using System.Collections.Generic;

-using System.Text;

-using OpenMetaverse;

-

-namespace OpenSim.Region.Physics.BulletSPlugin

-{

-public abstract class BSMotor

-{

-    public virtual void Reset() { }

-    public virtual void Zero() { }

-}

-// Can all the incremental stepping be replaced with motor classes?

-public class BSVMotor : BSMotor

-{

-    public Vector3 FrameOfReference { get; set; }

-    public Vector3 Offset { get; set; }

-

-    public float TimeScale { get; set; }

-    public float TargetValueDecayTimeScale { get; set; }

-    public Vector3 CurrentValueReductionTimescale { get; set; }

-    public float Efficiency { get; set; }

-

-    public Vector3 TargetValue { get; private set; }

-    public Vector3 CurrentValue { get; private set; }

-

-

-

-    BSVMotor(float timeScale, float decayTimeScale, Vector3 frictionTimeScale, float efficiency)

-    {

-        TimeScale = timeScale;

-        TargetValueDecayTimeScale = decayTimeScale;

-        CurrentValueReductionTimescale = frictionTimeScale;

-        Efficiency = efficiency;

-    }

-    public void SetCurrent(Vector3 current)

-    {

-        CurrentValue = current;

-    }

-    public void SetTarget(Vector3 target)

-    {

-        TargetValue = target;

-    }

-    public Vector3 Step(float timeStep)

-    {

-        if (CurrentValue.LengthSquared() > 0.001f)

-        {

-            // Vector3 origDir = Target;       // DEBUG

-            // Vector3 origVel = CurrentValue;   // DEBUG

-

-            // Add (desiredVelocity - currentAppliedVelocity) / howLongItShouldTakeToComplete

-            Vector3 addAmount = (TargetValue - CurrentValue)/(TargetValue) * timeStep;

-            CurrentValue += addAmount;

-

-            float decayFactor = (1.0f / TargetValueDecayTimeScale) * timeStep;

-            TargetValue *= (1f - decayFactor);

-

-            Vector3 frictionFactor = (Vector3.One / CurrentValueReductionTimescale) * timeStep;

-            CurrentValue *= (Vector3.One - frictionFactor);

-        }

-        else

-        {

-            // if what remains of direction is very small, zero it.

-            TargetValue = Vector3.Zero;

-            CurrentValue = Vector3.Zero;

-

-            // VDetailLog("{0},MoveLinear,zeroed", Prim.LocalID);

-        }

-        return CurrentValue;

-    }

-}

-

-public class BSFMotor : BSMotor

-{

-    public float TimeScale { get; set; }

-    public float DecayTimeScale { get; set; }

-    public float Friction { get; set; }

-    public float Efficiency { get; set; }

-

-    public float Target { get; private set; }

-    public float CurrentValue { get; private set; }

-

-    BSFMotor(float timeScale, float decayTimescale, float friction, float efficiency)

-    {

-    }

-    public void SetCurrent(float target)

-    {

-    }

-    public void SetTarget(float target)

-    {

-    }

-    public float Step(float timeStep)

-    {

-        return 0f;

-    }

-}

-public class BSPIDMotor : BSMotor

-{

-    // TODO: write and use this one

-    BSPIDMotor()

-    {

-    }

-}

-}

+using System;
+using System.Collections.Generic;
+using System.Text;
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+public abstract class BSMotor
+{
+    // Timescales and other things can be turned off by setting them to 'infinite'.
+    public const float Infinite = 10000f;
+    public readonly static Vector3 InfiniteVector = new Vector3(BSMotor.Infinite, BSMotor.Infinite, BSMotor.Infinite);
+
+    public BSMotor(string useName)
+    {
+        UseName = useName;
+        PhysicsScene = null;
+    }
+    public virtual void Reset() { }
+    public virtual void Zero() { }
+
+    public string UseName { get; private set; }
+    // Used only for outputting debug information. Might not be set so check for null.
+    public BSScene PhysicsScene { get; set; }
+    protected void MDetailLog(string msg, params Object[] parms)
+    {
+        if (PhysicsScene != null)
+        {
+            if (PhysicsScene.VehicleLoggingEnabled)
+            {
+                PhysicsScene.DetailLog(msg, parms);
+            }
+        }
+    }
+}
+// Can all the incremental stepping be replaced with motor classes?
+public class BSVMotor : BSMotor
+{
+    public Vector3 FrameOfReference { get; set; }
+    public Vector3 Offset { get; set; }
+
+    public float TimeScale { get; set; }
+    public float TargetValueDecayTimeScale { get; set; }
+    public Vector3 FrictionTimescale { get; set; }
+    public float Efficiency { get; set; }
+
+    public Vector3 TargetValue { get; private set; }
+    public Vector3 CurrentValue { get; private set; }
+
+    public BSVMotor(string useName)
+        : base(useName)
+    {
+        TimeScale = TargetValueDecayTimeScale = BSMotor.Infinite;
+        Efficiency = 1f;
+        FrictionTimescale = BSMotor.InfiniteVector;
+        CurrentValue = TargetValue = Vector3.Zero;
+    }
+    public BSVMotor(string useName, float timeScale, float decayTimeScale, Vector3 frictionTimeScale, float efficiency) 
+        : this(useName)
+    {
+        TimeScale = timeScale;
+        TargetValueDecayTimeScale = decayTimeScale;
+        FrictionTimescale = frictionTimeScale;
+        Efficiency = efficiency;
+        CurrentValue = TargetValue = Vector3.Zero;
+    }
+    public void SetCurrent(Vector3 current)
+    {
+        CurrentValue = current;
+    }
+    public void SetTarget(Vector3 target)
+    {
+        TargetValue = target;
+    }
+    public Vector3 Step(float timeStep)
+    {
+        Vector3 returnCurrent = Vector3.Zero;
+        if (!CurrentValue.ApproxEquals(TargetValue, 0.01f))
+        {
+            Vector3 origTarget = TargetValue;       // DEBUG
+            Vector3 origCurrVal = CurrentValue;   // DEBUG
+
+            // Addition =  (desiredVector - currentAppliedVector) / secondsItShouldTakeToComplete
+            Vector3 addAmount = (TargetValue - CurrentValue)/TimeScale * timeStep;
+            CurrentValue += addAmount;
+
+            returnCurrent = CurrentValue;
+
+            // The desired value reduces to zero which also reduces the difference with current.
+            // If the decay time is infinite, don't decay at all.
+            float decayFactor = 0f;
+            if (TargetValueDecayTimeScale != BSMotor.Infinite)
+            {
+                decayFactor = (1.0f / TargetValueDecayTimeScale) * timeStep;
+                TargetValue *= (1f - decayFactor);
+            }
+
+            Vector3 frictionFactor = Vector3.Zero;
+            if (FrictionTimescale != BSMotor.InfiniteVector)
+            {
+                // frictionFactor = (Vector3.One / FrictionTimescale) * timeStep;
+                frictionFactor.X = FrictionTimescale.X == BSMotor.Infinite ? 0f : (1f / FrictionTimescale.X) * timeStep;
+                frictionFactor.Y = FrictionTimescale.Y == BSMotor.Infinite ? 0f : (1f / FrictionTimescale.Y) * timeStep;
+                frictionFactor.Z = FrictionTimescale.Z == BSMotor.Infinite ? 0f : (1f / FrictionTimescale.Z) * timeStep;
+                CurrentValue *= (Vector3.One - frictionFactor);
+            }
+
+            MDetailLog("{0},BSVMotor.Step,nonZero,{1},origCurr={2},origTarget={3},timeStep={4},timeScale={5},addAmnt={6},targetDecay={7},decayFact={8},fricTS={9},frictFact={10}",
+                                BSScene.DetailLogZero, UseName, origCurrVal, origTarget,
+                                timeStep, TimeScale, addAmount,
+                                TargetValueDecayTimeScale, decayFactor,
+                                FrictionTimescale, frictionFactor);
+            MDetailLog("{0},BSVMotor.Step,nonZero,{1},curr={2},target={3},add={4},decay={5},frict={6},ret={7}",
+                                    BSScene.DetailLogZero, UseName, CurrentValue, TargetValue,
+                                    addAmount, decayFactor, frictionFactor, returnCurrent);
+        }
+        else
+        {
+            // Difference between what we have and target is small. Motor is done.
+            CurrentValue = Vector3.Zero;
+            TargetValue = Vector3.Zero;
+
+            MDetailLog("{0},BSVMotor.Step,zero,{1},curr={2},target={3},ret={4}",
+                                    BSScene.DetailLogZero, UseName, TargetValue, CurrentValue, returnCurrent);
+
+        }
+        return returnCurrent;
+    }
+    public override string ToString()
+    {
+        return String.Format("<{0},curr={1},targ={2},decayTS={3},frictTS={4}>",
+            UseName, CurrentValue, TargetValue, TargetValueDecayTimeScale, FrictionTimescale);
+    }
+}
+
+public class BSFMotor : BSMotor
+{
+    public float TimeScale { get; set; }
+    public float DecayTimeScale { get; set; }
+    public float Friction { get; set; }
+    public float Efficiency { get; set; }
+
+    public float Target { get; private set; }
+    public float CurrentValue { get; private set; }
+
+    public BSFMotor(string useName, float timeScale, float decayTimescale, float friction, float efficiency)
+        : base(useName)
+    {
+    }
+    public void SetCurrent(float target)
+    {
+    }
+    public void SetTarget(float target)
+    {
+    }
+    public float Step(float timeStep)
+    {
+        return 0f;
+    }
+}
+public class BSPIDMotor : BSMotor
+{
+    // TODO: write and use this one
+    public BSPIDMotor(string useName)
+        : base(useName)
+    {
+    }
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 2b3fa25..3fb0300 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -253,8 +253,9 @@ public sealed class BSPrim : BSPhysObject
         // Zero some other properties in the physics engine
         PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ZeroMotion", delegate()
         {
-            BulletSimAPI.SetInterpolationAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
-            BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
+            // DetailLog("{0},BSPrim.ZeroAngularMotion,call,rotVel={1}", LocalID, _rotationalVelocity);
+            BulletSimAPI.SetInterpolationAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
+            BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
         });
     }
 
@@ -329,7 +330,7 @@ public sealed class BSPrim : BSPhysObject
 
         if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
         {
-            float waterHeight = PhysicsScene.GetWaterLevelAtXYZ(_position);
+            float waterHeight = PhysicsScene.TerrainManager.GetWaterLevelAtXYZ(_position);
             // TODO: a floating motor so object will bob in the water
             if (Math.Abs(Position.Z - waterHeight) > 0.1f)
             {
@@ -342,13 +343,12 @@ public sealed class BSPrim : BSPhysObject
         // TODO: check for out of bounds
 
         // The above code computes a force to apply to correct any out-of-bounds problems. Apply same.
+        // TODO: This should be intergrated with a geneal physics action mechanism.
+        // TODO: This should be moderated with PID'ness.
         if (ret)
         {
-            PhysicsScene.TaintedObject(inTaintTime, "BSPrim.PositionSanityCheck:belowTerrain", delegate()
-            {
-                // Apply upforce and overcome gravity.
-                ForceVelocity = ForceVelocity + upForce - PhysicsScene.DefaultGravity;
-            });
+            // Apply upforce and overcome gravity.
+            AddForce(upForce - PhysicsScene.DefaultGravity, false, inTaintTime);
         }
         return ret;
     }
@@ -1381,54 +1381,16 @@ public sealed class BSPrim : BSPhysObject
 
     public override void UpdateProperties(EntityProperties entprop)
     {
-        /*
-        UpdatedProperties changed = 0;
-        // assign to the local variables so the normal set action does not happen
-        // if (_position != entprop.Position)
-        if (!_position.ApproxEquals(entprop.Position, POSITION_TOLERANCE))
-        {
-            _position = entprop.Position;
-            changed |= UpdatedProperties.Position;
-        }
-        // if (_orientation != entprop.Rotation)
-        if (!_orientation.ApproxEquals(entprop.Rotation, ROTATION_TOLERANCE))
-        {
-            _orientation = entprop.Rotation;
-            changed |= UpdatedProperties.Rotation;
-        }
-        // if (_velocity != entprop.Velocity)
-        if (!_velocity.ApproxEquals(entprop.Velocity, VELOCITY_TOLERANCE))
-        {
-            _velocity = entprop.Velocity;
-            changed |= UpdatedProperties.Velocity;
-        }
-        // if (_acceleration != entprop.Acceleration)
-        if (!_acceleration.ApproxEquals(entprop.Acceleration, ACCELERATION_TOLERANCE))
-        {
-            _acceleration = entprop.Acceleration;
-            changed |= UpdatedProperties.Acceleration;
-        }
-        // if (_rotationalVelocity != entprop.RotationalVelocity)
-        if (!_rotationalVelocity.ApproxEquals(entprop.RotationalVelocity, ROTATIONAL_VELOCITY_TOLERANCE))
-        {
-            _rotationalVelocity = entprop.RotationalVelocity;
-            changed |= UpdatedProperties.RotationalVel;
-        }
-        if (changed != 0)
+        // Updates only for individual prims and for the root object of a linkset.
+        if (Linkset.IsRoot(this))
         {
-            // Only update the position of single objects and linkset roots
-            if (Linkset.IsRoot(this))
+            // A temporary kludge to suppress the rotational effects introduced on vehicles by Bullet
+            // TODO: handle physics introduced by Bullet with computed vehicle physics.
+            if (_vehicle.IsActive)
             {
-                base.RequestPhysicsterseUpdate();
+                entprop.RotationalVelocity = OMV.Vector3.Zero;
             }
-        }
-        */
-
-        // Don't check for damping here -- it's done in BulletSim and SceneObjectPart.
 
-        // Updates only for individual prims and for the root object of a linkset.
-        if (Linkset.IsRoot(this))
-        {
             // Assign directly to the local variables so the normal set action does not happen
             _position = entprop.Position;
             _orientation = entprop.Rotation;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
index 27a78d1..0c80611 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
@@ -39,23 +39,10 @@ using log4net;
 using OpenMetaverse;
 
 // TODOs for BulletSim (for BSScene, BSPrim, BSCharacter and BulletSim)
-// Test sculpties (verified that they don't work)
-// Compute physics FPS reasonably
 // Based on material, set density and friction
-// Don't use constraints in linksets of non-physical objects. Means having to move children manually.
-// Four states of prim: Physical, regular, phantom and selected. Are we modeling these correctly?
-//     In SL one can set both physical and phantom (gravity, does not effect others, makes collisions with ground)
-//     At the moment, physical and phantom causes object to drop through the terrain
-// Physical phantom objects and related typing (collision options )
-// Check out llVolumeDetect. Must do something for that.
-// Use collision masks for collision with terrain and phantom objects
 // More efficient memory usage when passing hull information from BSPrim to BulletSim
-// Should prim.link() and prim.delink() membership checking happen at taint time?
-// Mesh sharing. Use meshHash to tell if we already have a hull of that shape and only create once.
 // Do attachments need to be handled separately? Need collision events. Do not collide with VolumeDetect
 // Implement LockAngularMotion
-// Decide if clearing forces is the right thing to do when setting position (BulletSim::SetObjectTranslation)
-// Remove mesh and Hull stuff. Use mesh passed to bullet and use convexdecom from bullet.
 // Add PID movement operations. What does ScenePresence.MoveToTarget do?
 // Check terrain size. 128 or 127?
 // Raycast
@@ -140,7 +127,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
     public const uint GROUNDPLANE_ID = 1;
     public const uint CHILDTERRAIN_ID = 2;  // Terrain allocated based on our mega-prim childre start here
 
-    private float m_waterLevel;
+    public float SimpleWaterLevel { get; set; }
     public BSTerrainManager TerrainManager { get; private set; }
 
     public ConfigurationParameters Params
@@ -195,6 +182,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
     private string m_physicsLoggingDir;
     private string m_physicsLoggingPrefix;
     private int m_physicsLoggingFileMinutes;
+    private bool m_physicsLoggingDoFlush;
     // 'true' of the vehicle code is to log lots of details
     public bool VehicleLoggingEnabled { get; private set; }
 
@@ -234,6 +222,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
         if (m_physicsLoggingEnabled)
         {
             PhysicsLogging = new Logging.LogWriter(m_physicsLoggingDir, m_physicsLoggingPrefix, m_physicsLoggingFileMinutes);
+            PhysicsLogging.ErrorLogger = m_log; // for DEBUG. Let's the logger output error messages.
         }
         else
         {
@@ -302,12 +291,20 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
                 m_physicsLoggingDir = pConfig.GetString("PhysicsLoggingDir", ".");
                 m_physicsLoggingPrefix = pConfig.GetString("PhysicsLoggingPrefix", "physics-%REGIONNAME%-");
                 m_physicsLoggingFileMinutes = pConfig.GetInt("PhysicsLoggingFileMinutes", 5);
+                m_physicsLoggingDoFlush = pConfig.GetBoolean("PhysicsLoggingDoFlush", false);
                 // Very detailed logging for vehicle debugging
                 VehicleLoggingEnabled = pConfig.GetBoolean("VehicleLoggingEnabled", false);
 
                 // Do any replacements in the parameters
                 m_physicsLoggingPrefix = m_physicsLoggingPrefix.Replace("%REGIONNAME%", RegionName);
             }
+
+            // The material characteristics.
+            BSMaterials.InitializeFromDefaults(Params);
+            if (pConfig != null)
+            {
+                BSMaterials.InitializefromParameters(pConfig);
+            }
         }
     }
 
@@ -499,7 +496,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
 
         try
         {
-            if (VehicleLoggingEnabled) DumpVehicles();  // DEBUG
+            // if (VehicleLoggingEnabled) DumpVehicles();  // DEBUG
             if (PhysicsLogging.Enabled) beforeTime = Util.EnvironmentTickCount();
 
             numSubSteps = BulletSimAPI.PhysicsStep2(World.ptr, timeStep, m_maxSubSteps, m_fixedTimeStep,
@@ -508,7 +505,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             if (PhysicsLogging.Enabled) simTime = Util.EnvironmentTickCountSubtract(beforeTime);
             DetailLog("{0},Simulate,call, frame={1}, nTaints={2}, simTime={3}, substeps={4}, updates={5}, colliders={6}",
                         DetailLogZero, m_simulationStep, numTaints, simTime, numSubSteps, updatedEntityCount, collidersCount);
-            if (VehicleLoggingEnabled) DumpVehicles();  // DEBUG
+            // if (VehicleLoggingEnabled) DumpVehicles();  // DEBUG
         }
         catch (Exception e)
         {
@@ -520,9 +517,9 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             collidersCount = 0;
         }
 
-        // Don't have to use the pointers passed back since we know it is the same pinned memory we passed in
+        // Don't have to use the pointers passed back since we know it is the same pinned memory we passed in.
 
-        // Get a value for 'now' so all the collision and update routines don't have to get their own
+        // Get a value for 'now' so all the collision and update routines don't have to get their own.
         SimulationNowTime = Util.EnvironmentTickCount();
 
         // If there were collisions, process them by sending the event to the prim.
@@ -568,6 +565,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
                 ObjectsWithCollisions.Remove(po);
             ObjectsWithNoMoreCollisions.Clear();
         }
+        // Done with collisions.
 
         // If any of the objects had updated properties, tell the object it has been changed by the physics engine
         if (updatedEntityCount > 0)
@@ -591,9 +589,8 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
 
         // The physics engine returns the number of milliseconds it simulated this call.
         // These are summed and normalized to one second and divided by 1000 to give the reported physics FPS.
-        // We multiply by 55 to give a recognizable running rate (55 or less).
-        return numSubSteps * m_fixedTimeStep * 1000 * 55;
-        // return timeStep * 1000 * 55;
+        // Multiply by 55 to give a nominal frame rate of 55.
+        return (float)numSubSteps * m_fixedTimeStep * 1000f * 55f;
     }
 
     // Something has collided
@@ -639,12 +636,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
 
     public override void SetWaterLevel(float baseheight)
     {
-        m_waterLevel = baseheight;
-    }
-    // Someday....
-    public float GetWaterLevelAtXYZ(Vector3 loc)
-    {
-        return m_waterLevel;
+        SimpleWaterLevel = baseheight;
     }
 
     public override void DeleteTerrain()
@@ -1069,7 +1061,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s,p,l,v) => { s.PID_P = v; } ),
 
         new ParameterDefn("DefaultFriction", "Friction factor used on new objects",
-            0.5f,
+            0.2f,
             (s,cf,p,v) => { s.m_params[0].defaultFriction = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].defaultFriction; },
             (s,p,l,v) => { s.m_params[0].defaultFriction = v; } ),
@@ -1084,7 +1076,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s) => { return s.m_params[0].defaultRestitution; },
             (s,p,l,v) => { s.m_params[0].defaultRestitution = v; } ),
         new ParameterDefn("CollisionMargin", "Margin around objects before collisions are calculated (must be zero!)",
-            0f,
+            0.04f,
             (s,cf,p,v) => { s.m_params[0].collisionMargin = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].collisionMargin; },
             (s,p,l,v) => { s.m_params[0].collisionMargin = v; } ),
@@ -1151,7 +1143,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s) => { return s.m_params[0].terrainImplementation; },
             (s,p,l,v) => { s.m_params[0].terrainImplementation = v; } ),
         new ParameterDefn("TerrainFriction", "Factor to reduce movement against terrain surface" ,
-            0.5f,
+            0.3f,
             (s,cf,p,v) => { s.m_params[0].terrainFriction = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].terrainFriction; },
             (s,p,l,v) => { s.m_params[0].terrainFriction = v;  /* TODO: set on real terrain */} ),
@@ -1165,13 +1157,19 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s,cf,p,v) => { s.m_params[0].terrainRestitution = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].terrainRestitution; },
             (s,p,l,v) => { s.m_params[0].terrainRestitution = v;  /* TODO: set on real terrain */ } ),
+        new ParameterDefn("TerrainCollisionMargin", "Margin where collision checking starts" ,
+            0.04f,
+            (s,cf,p,v) => { s.m_params[0].terrainCollisionMargin = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].terrainCollisionMargin; },
+            (s,p,l,v) => { s.m_params[0].terrainCollisionMargin = v;  /* TODO: set on real terrain */ } ),
+
         new ParameterDefn("AvatarFriction", "Factor to reduce movement against an avatar. Changed on avatar recreation.",
             0.2f,
             (s,cf,p,v) => { s.m_params[0].avatarFriction = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].avatarFriction; },
             (s,p,l,v) => { s.UpdateParameterObject(ref s.m_params[0].avatarFriction, p, l, v); } ),
         new ParameterDefn("AvatarStandingFriction", "Avatar friction when standing. Changed on avatar recreation.",
-            10f,
+            10.0f,
             (s,cf,p,v) => { s.m_params[0].avatarStandingFriction = cf.GetFloat(p, v); },
             (s) => { return s.m_params[0].avatarStandingFriction; },
             (s,p,l,v) => { s.m_params[0].avatarStandingFriction = v; } ),
@@ -1206,6 +1204,11 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s) => { return s.m_params[0].avatarContactProcessingThreshold; },
             (s,p,l,v) => { s.UpdateParameterObject(ref s.m_params[0].avatarContactProcessingThreshold, p, l, v); } ),
 
+        new ParameterDefn("VehicleAngularDamping", "Factor to damp vehicle angular movement per second (0.0 - 1.0)",
+            0.95f,
+            (s,cf,p,v) => { s.m_params[0].vehicleAngularDamping = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].vehicleAngularDamping; },
+            (s,p,l,v) => { s.m_params[0].vehicleAngularDamping = v; } ),
 
             new ParameterDefn("MaxPersistantManifoldPoolSize", "Number of manifolds pooled (0 means default of 4096)",
             0f,
@@ -1487,7 +1490,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
     {
         PhysicsLogging.Write(msg, args);
         // Add the Flush() if debugging crashes. Gets all the messages written out.
-        // PhysicsLogging.Flush();
+        if (m_physicsLoggingDoFlush) PhysicsLogging.Flush();
     }
     // Used to fill in the LocalID when there isn't one. It's the correct number of characters.
     public const string DetailLogZero = "0000000000";
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs
index 3ca756c..0cb151e 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs
@@ -93,7 +93,7 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
     {
         m_mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, m_mapInfo.ID,
                                 m_mapInfo.minCoords, m_mapInfo.maxCoords, 
-                                m_mapInfo.heightMap, BSTerrainManager.TERRAIN_COLLISION_MARGIN);
+                                m_mapInfo.heightMap, PhysicsScene.Params.terrainCollisionMargin);
 
         // Create the terrain shape from the mapInfo
         m_mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(m_mapInfo.Ptr),
@@ -148,7 +148,7 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
     }
 
     // The passed position is relative to the base of the region.
-    public override float GetHeightAtXYZ(Vector3 pos)
+    public override float GetTerrainHeightAtXYZ(Vector3 pos)
     {
         float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
 
@@ -166,5 +166,11 @@ public sealed class BSTerrainHeightmap : BSTerrainPhys
         }
         return ret;
     }
+
+    // The passed position is relative to the base of the region.
+    public override float GetWaterLevelAtXYZ(Vector3 pos)
+    {
+        return PhysicsScene.SimpleWaterLevel;
+    }
 }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
index 23fcfd3..17d9536 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
@@ -62,7 +62,8 @@ public abstract class BSTerrainPhys : IDisposable
         ID = id;
     }
     public abstract void Dispose();
-    public abstract float GetHeightAtXYZ(Vector3 pos);
+    public abstract float GetTerrainHeightAtXYZ(Vector3 pos);
+    public abstract float GetWaterLevelAtXYZ(Vector3 pos);
 }
 
 // ==========================================================================================
@@ -75,13 +76,12 @@ public sealed class BSTerrainManager
     public const float HEIGHT_INITIALIZATION = 24.987f;
     public const float HEIGHT_INITIAL_LASTHEIGHT = 24.876f;
     public const float HEIGHT_GETHEIGHT_RET = 24.765f;
+    public const float WATER_HEIGHT_GETHEIGHT_RET = 19.998f;
 
     // If the min and max height are equal, we reduce the min by this
     //    amount to make sure that a bounding box is built for the terrain.
     public const float HEIGHT_EQUAL_FUDGE = 0.2f;
 
-    public const float TERRAIN_COLLISION_MARGIN = 0.0f;
-
     // Until the whole simulator is changed to pass us the region size, we rely on constants.
     public Vector3 DefaultRegionSize = new Vector3(Constants.RegionSize, Constants.RegionSize, Constants.RegionHeight);
 
@@ -129,7 +129,8 @@ public sealed class BSTerrainManager
     {
         // The ground plane is here to catch things that are trying to drop to negative infinity
         BulletShape groundPlaneShape = new BulletShape(
-                    BulletSimAPI.CreateGroundPlaneShape2(BSScene.GROUNDPLANE_ID, 1f, TERRAIN_COLLISION_MARGIN),
+                    BulletSimAPI.CreateGroundPlaneShape2(BSScene.GROUNDPLANE_ID, 1f, 
+                                    PhysicsScene.Params.terrainCollisionMargin),
                     BSPhysicsShapeType.SHAPE_GROUNDPLANE);
         m_groundPlane = new BulletBody(BSScene.GROUNDPLANE_ID,
                         BulletSimAPI.CreateBodyWithDefaultMotionState2(groundPlaneShape.ptr, BSScene.GROUNDPLANE_ID,
@@ -165,17 +166,22 @@ public sealed class BSTerrainManager
     // Release all the terrain we have allocated
     public void ReleaseTerrain()
     {
-        foreach (KeyValuePair<Vector3, BSTerrainPhys> kvp in m_terrains)
+        lock (m_terrains)
         {
-            kvp.Value.Dispose();
+            foreach (KeyValuePair<Vector3, BSTerrainPhys> kvp in m_terrains)
+            {
+                kvp.Value.Dispose();
+            }
+            m_terrains.Clear();
         }
-        m_terrains.Clear();
     }
 
     // The simulator wants to set a new heightmap for the terrain.
     public void SetTerrain(float[] heightMap) {
         float[] localHeightMap = heightMap;
-        PhysicsScene.TaintedObject("TerrainManager.SetTerrain", delegate()
+        // If there are multiple requests for changes to the same terrain between ticks,
+        //      only do that last one.
+        PhysicsScene.PostTaintObject("TerrainManager.SetTerrain-"+ m_worldOffset.ToString(), 0, delegate()
         {
             if (m_worldOffset != Vector3.Zero && MegaRegionParentPhysicsScene != null)
             {
@@ -211,6 +217,7 @@ public sealed class BSTerrainManager
     //     terrain shape is created and added to the body.
     //     This call is most often used to update the heightMap and parameters of the terrain.
     // (The above does suggest that some simplification/refactoring is in order.)
+    // Called during taint-time.
     private void UpdateTerrain(uint id, float[] heightMap, 
                             Vector3 minCoords, Vector3 maxCoords, bool inTaintTime)
     {
@@ -220,7 +227,7 @@ public sealed class BSTerrainManager
         // Find high and low points of passed heightmap.
         // The min and max passed in is usually the area objects can be in (maximum
         //     object height, for instance). The terrain wants the bounding box for the
-        //     terrain so we replace passed min and max Z with the actual terrain min/max Z.
+        //     terrain so replace passed min and max Z with the actual terrain min/max Z.
         float minZ = float.MaxValue;
         float maxZ = float.MinValue;
         foreach (float height in heightMap)
@@ -238,15 +245,15 @@ public sealed class BSTerrainManager
 
         Vector3 terrainRegionBase = new Vector3(minCoords.X, minCoords.Y, 0f);
 
-        BSTerrainPhys terrainPhys;
-        if (m_terrains.TryGetValue(terrainRegionBase, out terrainPhys))
+        lock (m_terrains)
         {
-            // There is already a terrain in this spot. Free the old and build the new.
-            DetailLog("{0},UpdateTerrain:UpdateExisting,call,id={1},base={2},minC={3},maxC={4}",
-                            BSScene.DetailLogZero, id, terrainRegionBase, minCoords, minCoords);
-
-            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateTerrain:UpdateExisting", delegate()
+            BSTerrainPhys terrainPhys;
+            if (m_terrains.TryGetValue(terrainRegionBase, out terrainPhys))
             {
+                // There is already a terrain in this spot. Free the old and build the new.
+                DetailLog("{0},UpdateTerrain:UpdateExisting,call,id={1},base={2},minC={3},maxC={4}",
+                                BSScene.DetailLogZero, id, terrainRegionBase, minCoords, minCoords);
+
                 // Remove old terrain from the collection
                 m_terrains.Remove(terrainRegionBase);
                 // Release any physical memory it may be using.
@@ -271,35 +278,24 @@ public sealed class BSTerrainManager
                     // I hate doing this, but just bail
                     return;
                 }
-            });
-        }
-        else
-        {
-            // We don't know about this terrain so either we are creating a new terrain or
-            //    our mega-prim child is giving us a new terrain to add to the phys world
-
-            // if this is a child terrain, calculate a unique terrain id
-            uint newTerrainID = id;
-            if (newTerrainID >= BSScene.CHILDTERRAIN_ID)
-                newTerrainID = ++m_terrainCount;
-
-            float[] heightMapX = heightMap;
-            Vector3 minCoordsX = minCoords;
-            Vector3 maxCoordsX = maxCoords;
+            }
+            else
+            {
+                // We don't know about this terrain so either we are creating a new terrain or
+                //    our mega-prim child is giving us a new terrain to add to the phys world
 
-            DetailLog("{0},UpdateTerrain:NewTerrain,call,id={1}, minC={2}, maxC={3}",
-                            BSScene.DetailLogZero, newTerrainID, minCoords, minCoords);
+                // if this is a child terrain, calculate a unique terrain id
+                uint newTerrainID = id;
+                if (newTerrainID >= BSScene.CHILDTERRAIN_ID)
+                    newTerrainID = ++m_terrainCount;
 
-            // Code that must happen at taint-time
-            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateTerrain:NewTerrain", delegate()
-            {
-                DetailLog("{0},UpdateTerrain:NewTerrain,taint,baseX={1},baseY={2}", 
-                                            BSScene.DetailLogZero, minCoordsX.X, minCoordsX.Y);
+                DetailLog("{0},UpdateTerrain:NewTerrain,taint,newID={1},minCoord={2},maxCoord={3}",
+                                            BSScene.DetailLogZero, newTerrainID, minCoords, minCoords);
                 BSTerrainPhys newTerrainPhys = BuildPhysicalTerrain(terrainRegionBase, id, heightMap, minCoords, maxCoords);
                 m_terrains.Add(terrainRegionBase, newTerrainPhys);
 
                 m_terrainModified = true;
-            });
+            }
         }
     }
 
@@ -349,6 +345,7 @@ public sealed class BSTerrainManager
         //    with the same parameters as last time.
         if (!m_terrainModified && lastHeightTX == tX && lastHeightTY == tY)
             return lastHeight;
+        m_terrainModified = false;
 
         lastHeightTX = tX;
         lastHeightTY = tY;
@@ -358,20 +355,47 @@ public sealed class BSTerrainManager
         int offsetY = ((int)(tY / (int)DefaultRegionSize.Y)) * (int)DefaultRegionSize.Y;
         Vector3 terrainBaseXYZ = new Vector3(offsetX, offsetY, 0f);
 
-        BSTerrainPhys physTerrain;
-        if (m_terrains.TryGetValue(terrainBaseXYZ, out physTerrain))
+        lock (m_terrains)
         {
-            ret = physTerrain.GetHeightAtXYZ(loc - terrainBaseXYZ);
-            DetailLog("{0},BSTerrainManager.GetTerrainHeightAtXYZ,loc={1},base={2},height={3}",
-                                             BSScene.DetailLogZero, loc, terrainBaseXYZ, ret);
+            BSTerrainPhys physTerrain;
+            if (m_terrains.TryGetValue(terrainBaseXYZ, out physTerrain))
+            {
+                ret = physTerrain.GetTerrainHeightAtXYZ(loc - terrainBaseXYZ);
+            }
+            else
+            {
+                PhysicsScene.Logger.ErrorFormat("{0} GetTerrainHeightAtXY: terrain not found: region={1}, x={2}, y={3}",
+                        LogHeader, PhysicsScene.RegionName, tX, tY);
+            }
         }
-        else
+        lastHeight = ret;
+        return ret;
+    }
+
+    public float GetWaterLevelAtXYZ(Vector3 pos)
+    {
+        float ret = WATER_HEIGHT_GETHEIGHT_RET;
+
+        float tX = pos.X;
+        float tY = pos.Y;
+
+        Vector3 terrainBaseXYZ = Vector3.Zero;
+        terrainBaseXYZ.X = ((int)(tX / (int)DefaultRegionSize.X)) * (int)DefaultRegionSize.X;
+        terrainBaseXYZ.Y = ((int)(tY / (int)DefaultRegionSize.Y)) * (int)DefaultRegionSize.Y;
+
+        lock (m_terrains)
         {
-            PhysicsScene.Logger.ErrorFormat("{0} GetTerrainHeightAtXY: terrain not found: region={1}, x={2}, y={3}",
-                    LogHeader, PhysicsScene.RegionName, tX, tY);
+            BSTerrainPhys physTerrain;
+            if (m_terrains.TryGetValue(terrainBaseXYZ, out physTerrain))
+            {
+                ret = physTerrain.GetWaterLevelAtXYZ(pos);
+            }
+            else
+            {
+                PhysicsScene.Logger.ErrorFormat("{0} GetWaterHeightAtXY: terrain not found: region={1}, x={2}, y={3}",
+                        LogHeader, PhysicsScene.RegionName, tX, tY);
+            }
         }
-        m_terrainModified = false;
-        lastHeight = ret;
         return ret;
     }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
index dca7150..7e93ab4 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
@@ -88,9 +88,11 @@ public sealed class BSTerrainMesh : BSTerrainPhys
             // Something is very messed up and a crash is in our future.
             return;
         }
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,meshed,indices={1},indSz={2},vertices={3},vertSz={4}", 
+                                ID, indicesCount, indices.Length, verticesCount, vertices.Length);
 
         m_terrainShape = new BulletShape(BulletSimAPI.CreateMeshShape2(PhysicsScene.World.ptr,
-                                        indicesCount, indices, verticesCount, vertices),
+                                                    indicesCount, indices, verticesCount, vertices),
                                         BSPhysicsShapeType.SHAPE_MESH);
         if (m_terrainShape.ptr == IntPtr.Zero)
         {
@@ -122,10 +124,10 @@ public sealed class BSTerrainMesh : BSTerrainPhys
         // Static objects are not very massive.
         BulletSimAPI.SetMassProps2(m_terrainBody.ptr, 0f, Vector3.Zero);
 
-        // Return the new terrain to the world of physical objects
+        // Put the new terrain to the world of physical objects
         BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
 
-        // redo its bounding box now that it is in the world
+        // Redo its bounding box now that it is in the world
         BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_terrainBody.ptr);
 
         BulletSimAPI.SetCollisionFilterMask2(m_terrainBody.ptr,
@@ -146,7 +148,7 @@ public sealed class BSTerrainMesh : BSTerrainPhys
         }
     }
 
-    public override float GetHeightAtXYZ(Vector3 pos)
+    public override float GetTerrainHeightAtXYZ(Vector3 pos)
     {
         // For the moment use the saved heightmap to get the terrain height.
         // TODO: raycast downward to find the true terrain below the position.
@@ -167,6 +169,12 @@ public sealed class BSTerrainMesh : BSTerrainPhys
         return ret;
     }
 
+    // The passed position is relative to the base of the region.
+    public override float GetWaterLevelAtXYZ(Vector3 pos)
+    {
+        return PhysicsScene.SimpleWaterLevel;
+    }
+
     // Convert the passed heightmap to mesh information suitable for CreateMeshShape2().
     // Return 'true' if successfully created.
     public static bool ConvertHeightmapToMesh(
@@ -188,6 +196,11 @@ public sealed class BSTerrainMesh : BSTerrainPhys
         // Simple mesh creation which assumes magnification == 1.
         // TODO: do a more general solution that scales, adds new vertices and smoothes the result.
 
+        // Create an array of vertices that is sizeX+1 by sizeY+1 (note the loop
+        //    from zero to <= sizeX). The triangle indices are then generated as two triangles
+        //    per heightmap point. There are sizeX by sizeY of these squares. The extra row and
+        //    column of vertices are used to complete the triangles of the last row and column
+        //    of the heightmap.
         try
         {
             // One vertice per heightmap value plus the vertices off the top and bottom edge.
@@ -200,16 +213,18 @@ public sealed class BSTerrainMesh : BSTerrainPhys
             float magY = (float)sizeY / extentY;
             physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,totVert={1},totInd={2},extentBase={3},magX={4},magY={5}",
                                     BSScene.DetailLogZero, totalVertices, totalIndices, extentBase, magX, magY);
+            float minHeight = float.MaxValue;
             // Note that sizeX+1 vertices are created since there is land between this and the next region.
             for (int yy = 0; yy <= sizeY; yy++)
             {
-                for (int xx = 0; xx <= sizeX; xx++)     // Hint: the "<=" means we got through sizeX + 1 times
+                for (int xx = 0; xx <= sizeX; xx++)     // Hint: the "<=" means we go around sizeX + 1 times
                 {
                     int offset = yy * sizeX + xx;
-                    // Extend the height from the height from the last row or column
+                    // Extend the height with the height from the last row or column
                     if (yy == sizeY) offset -= sizeX;
                     if (xx == sizeX) offset -= 1;
                     float height = heightMap[offset];
+                    minHeight = Math.Min(minHeight, height);
                     vertices[verticesCount + 0] = (float)xx * magX + extentBase.X;
                     vertices[verticesCount + 1] = (float)yy * magY + extentBase.Y;
                     vertices[verticesCount + 2] = height + extentBase.Z;
@@ -217,14 +232,12 @@ public sealed class BSTerrainMesh : BSTerrainPhys
                 }
             }
             verticesCount = verticesCount / 3;
-            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeVerts,verCount={1}", 
-                                            BSScene.DetailLogZero, verticesCount);
 
             for (int yy = 0; yy < sizeY; yy++)
             {
                 for (int xx = 0; xx < sizeX; xx++)
                 {
-                    int offset = yy * sizeX + xx;
+                    int offset = yy * (sizeX + 1) + xx;
                     // Each vertices is presumed to be the upper left corner of a box of two triangles
                     indices[indicesCount + 0] = offset;
                     indices[indicesCount + 1] = offset + 1;
@@ -235,8 +248,7 @@ public sealed class BSTerrainMesh : BSTerrainPhys
                     indicesCount += 6;
                 }
             }
-            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeIndices,indCount={1}",   // DEEBUG DEBUG DEBUG
-                                                        LogHeader, indicesCount);                        // DEBUG
+
             ret = true;
         }
         catch (Exception e)
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
index e60a760..1e003e6 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
@@ -287,6 +287,8 @@ public struct ConfigurationParameters
     public float terrainFriction;
     public float terrainHitFraction;
     public float terrainRestitution;
+    public float terrainCollisionMargin;
+
     public float avatarFriction;
     public float avatarStandingFriction;
     public float avatarDensity;
@@ -296,6 +298,8 @@ public struct ConfigurationParameters
     public float avatarCapsuleHeight;
         public float avatarContactProcessingThreshold;
 
+    public float vehicleAngularDamping;
+
         public float maxPersistantManifoldPoolSize;
         public float maxCollisionAlgorithmPoolSize;
         public float shouldDisableContactPoolDynamicAllocation;
@@ -353,7 +357,7 @@ public enum CollisionFlags : uint
     CF_CHARACTER_OBJECT              = 1 << 4,
     CF_DISABLE_VISUALIZE_OBJECT      = 1 << 5,
     CF_DISABLE_SPU_COLLISION_PROCESS = 1 << 6,
-    // Following used by BulletSim to control collisions
+    // Following used by BulletSim to control collisions and updates
     BS_SUBSCRIBE_COLLISION_EVENTS    = 1 << 10,
     BS_FLOATS_ON_WATER               = 1 << 11,
     BS_NONE                          = 0,
@@ -482,6 +486,9 @@ public static extern IntPtr BuildNativeShape2(IntPtr world, ShapeData shapeData)
 public static extern bool IsNativeShape2(IntPtr shape);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern void SetShapeCollisionMargin(IntPtr shape, float margin);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern IntPtr BuildCapsuleShape2(IntPtr world, float radius, float height, Vector3 scale);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
diff --git a/OpenSim/Region/Physics/Meshing/Meshmerizer.cs b/OpenSim/Region/Physics/Meshing/Meshmerizer.cs
index f629c4d..9262a9e 100644
--- a/OpenSim/Region/Physics/Meshing/Meshmerizer.cs
+++ b/OpenSim/Region/Physics/Meshing/Meshmerizer.cs
@@ -321,6 +321,9 @@ namespace OpenSim.Region.Physics.Meshing
 
             if (primShape.SculptData.Length <= 0)
             {
+                // XXX: At the moment we can not log here since ODEPrim, for instance, ends up triggering this
+                // method twice - once before it has loaded sculpt data from the asset service and once afterwards.
+                // The first time will always call with unloaded SculptData if this needs to be uploaded.
 //                m_log.ErrorFormat("[MESH]: asset data for {0} is zero length", primName);
                 return false;
             }
diff --git a/OpenSim/Region/Physics/OdePlugin/ODEPrim.cs b/OpenSim/Region/Physics/OdePlugin/ODEPrim.cs
index a59f63f..d09aa62 100644
--- a/OpenSim/Region/Physics/OdePlugin/ODEPrim.cs
+++ b/OpenSim/Region/Physics/OdePlugin/ODEPrim.cs
@@ -3367,6 +3367,11 @@ Console.WriteLine(" JointCreateFixed");
                 _pbs.SculptData = new byte[asset.Data.Length];
                 asset.Data.CopyTo(_pbs.SculptData, 0);
 //                m_assetFailed = false;
+
+//                m_log.DebugFormat(
+//                    "[ODE PRIM]: Received mesh/sculpt data asset {0} with {1} bytes for {2} at {3} in {4}", 
+//                    _pbs.SculptTexture, _pbs.SculptData.Length, Name, _position, _parent_scene.Name);
+
                 m_taintshape = true;
                _parent_scene.AddPhysicsActorTaint(this);
             }