Merge branch 'master' of ssh://opensimulator.org/var/git/opensim

19 files changed, 2154 insertions, 1376 deletions

diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index 2d02a82..a16d174 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -1,5 +1,5 @@
    <<<>>>>The following people have contributed to OpenSim (Thank you 
-for your effort!)
+for your effort!) 
 
 = Current OpenSim Developers (in very rough order of appearance) =
 These folks represent the current core team for OpenSim, and are the
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BS6DofConstraint.cs b/OpenSim/Region/Physics/BulletSPlugin/BS6DofConstraint.cs
index 683bc51..3306a97 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BS6DofConstraint.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BS6DofConstraint.cs
@@ -34,6 +34,10 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
 public class BS6DofConstraint : BSConstraint
 {
+    private static string LogHeader = "[BULLETSIM 6DOF CONSTRAINT]";
+
+    public override ConstraintType Type { get { return ConstraintType.D6_CONSTRAINT_TYPE; } }
+
     // Create a btGeneric6DofConstraint
     public BS6DofConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,
                     Vector3 frame1, Quaternion frame1rot,
@@ -44,11 +48,14 @@ public class BS6DofConstraint : BSConstraint
         m_body1 = obj1;
         m_body2 = obj2;
         m_constraint = new BulletConstraint(
-                            BulletSimAPI.Create6DofConstraint2(m_world.Ptr, m_body1.Ptr, m_body2.Ptr,
+                            BulletSimAPI.Create6DofConstraint2(m_world.ptr, m_body1.ptr, m_body2.ptr,
                                 frame1, frame1rot,
                                 frame2, frame2rot,
                                 useLinearReferenceFrameA, disableCollisionsBetweenLinkedBodies));
         m_enabled = true;
+        world.physicsScene.DetailLog("{0},BS6DofConstraint,createFrame,wID={1}, rID={2}, rBody={3}, cID={4}, cBody={5}",
+                            BSScene.DetailLogZero, world.worldID,
+                            obj1.ID, obj1.ptr.ToString("X"), obj2.ID, obj2.ptr.ToString("X"));
     }
 
     public BS6DofConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,
@@ -58,11 +65,36 @@ public class BS6DofConstraint : BSConstraint
         m_world = world;
         m_body1 = obj1;
         m_body2 = obj2;
-        m_constraint = new BulletConstraint(
-                            BulletSimAPI.Create6DofConstraintToPoint2(m_world.Ptr, m_body1.Ptr, m_body2.Ptr,
-                                joinPoint,
-                                useLinearReferenceFrameA, disableCollisionsBetweenLinkedBodies));
-        m_enabled = true;
+        if (obj1.ptr == IntPtr.Zero || obj2.ptr == IntPtr.Zero)
+        {
+            world.physicsScene.DetailLog("{0},BS6DOFConstraint,badBodyPtr,wID={1}, rID={2}, rBody={3}, cID={4}, cBody={5}",
+                            BSScene.DetailLogZero, world.worldID,
+                            obj1.ID, obj1.ptr.ToString("X"), obj2.ID, obj2.ptr.ToString("X"));
+            world.physicsScene.Logger.ErrorFormat("{0} Attempt to build 6DOF constraint with missing bodies: wID={1}, rID={2}, rBody={3}, cID={4}, cBody={5}",
+                            "[BULLETSIM 6DOF CONSTRAINT]", world.worldID,
+                            obj1.ID, obj1.ptr.ToString("X"), obj2.ID, obj2.ptr.ToString("X"));
+            m_enabled = false;
+        }
+        else
+        {
+            m_constraint = new BulletConstraint(
+                                BulletSimAPI.Create6DofConstraintToPoint2(m_world.ptr, m_body1.ptr, m_body2.ptr,
+                                    joinPoint,
+                                    useLinearReferenceFrameA, disableCollisionsBetweenLinkedBodies));
+            world.physicsScene.DetailLog("{0},BS6DofConstraint,createMidPoint,wID={1}, csrt={2}, rID={3}, rBody={4}, cID={5}, cBody={6}",
+                                BSScene.DetailLogZero, world.worldID, m_constraint.ptr.ToString("X"),
+                                obj1.ID, obj1.ptr.ToString("X"), obj2.ID, obj2.ptr.ToString("X"));
+            if (m_constraint.ptr == IntPtr.Zero)
+            {
+                world.physicsScene.Logger.ErrorFormat("{0} Failed creation of 6Dof constraint. rootID={1}, childID={2}",
+                                LogHeader, obj1.ID, obj2.ID);
+                m_enabled = false;
+            }
+            else
+            {
+                m_enabled = true;
+            }
+        }
     }
 
     public bool SetFrames(Vector3 frameA, Quaternion frameArot, Vector3 frameB, Quaternion frameBrot)
@@ -70,7 +102,7 @@ public class BS6DofConstraint : BSConstraint
         bool ret = false;
         if (m_enabled)
         {
-            BulletSimAPI.SetFrames2(m_constraint.Ptr, frameA, frameArot, frameB, frameBrot);
+            BulletSimAPI.SetFrames2(m_constraint.ptr, frameA, frameArot, frameB, frameBrot);
             ret = true;
         }
         return ret;
@@ -81,9 +113,9 @@ public class BS6DofConstraint : BSConstraint
         bool ret = false;
         if (m_enabled)
         {
-            BulletSimAPI.SetConstraintParam2(m_constraint.Ptr, ConstraintParams.BT_CONSTRAINT_STOP_CFM, cfm, ConstraintParamAxis.AXIS_ALL);
-            BulletSimAPI.SetConstraintParam2(m_constraint.Ptr, ConstraintParams.BT_CONSTRAINT_STOP_ERP, erp, ConstraintParamAxis.AXIS_ALL);
-            BulletSimAPI.SetConstraintParam2(m_constraint.Ptr, ConstraintParams.BT_CONSTRAINT_CFM, cfm, ConstraintParamAxis.AXIS_ALL);
+            BulletSimAPI.SetConstraintParam2(m_constraint.ptr, ConstraintParams.BT_CONSTRAINT_STOP_CFM, cfm, ConstraintParamAxis.AXIS_ALL);
+            BulletSimAPI.SetConstraintParam2(m_constraint.ptr, ConstraintParams.BT_CONSTRAINT_STOP_ERP, erp, ConstraintParamAxis.AXIS_ALL);
+            BulletSimAPI.SetConstraintParam2(m_constraint.ptr, ConstraintParams.BT_CONSTRAINT_CFM, cfm, ConstraintParamAxis.AXIS_ALL);
             ret = true;
         }
         return ret;
@@ -94,7 +126,7 @@ public class BS6DofConstraint : BSConstraint
         bool ret = false;
         float onOff = useOffset ? ConfigurationParameters.numericTrue : ConfigurationParameters.numericFalse;
         if (m_enabled)
-            ret = BulletSimAPI.UseFrameOffset2(m_constraint.Ptr, onOff);
+            ret = BulletSimAPI.UseFrameOffset2(m_constraint.ptr, onOff);
         return ret;
     }
 
@@ -103,7 +135,7 @@ public class BS6DofConstraint : BSConstraint
         bool ret = false;
         float onOff = enable ? ConfigurationParameters.numericTrue : ConfigurationParameters.numericFalse;
         if (m_enabled)
-            ret = BulletSimAPI.TranslationalLimitMotor2(m_constraint.Ptr, onOff, targetVelocity, maxMotorForce);
+            ret = BulletSimAPI.TranslationalLimitMotor2(m_constraint.ptr, onOff, targetVelocity, maxMotorForce);
         return ret;
     }
 
@@ -111,7 +143,7 @@ public class BS6DofConstraint : BSConstraint
     {
         bool ret = false;
         if (m_enabled)
-            ret = BulletSimAPI.SetBreakingImpulseThreshold2(m_constraint.Ptr, threshold);
+            ret = BulletSimAPI.SetBreakingImpulseThreshold2(m_constraint.ptr, threshold);
         return ret;
     }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index 526dbad..b88ec3c 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -28,7 +28,7 @@ using System;
 using System.Collections.Generic;
 using System.Reflection;
 using log4net;
-using OpenMetaverse;
+using OMV = OpenMetaverse;
 using OpenSim.Framework;
 using OpenSim.Region.Physics.Manager;
 
@@ -39,48 +39,35 @@ public class BSCharacter : BSPhysObject
     private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
     private static readonly string LogHeader = "[BULLETS CHAR]";
 
-    public BSScene Scene { get; private set; }
-    private String _avName;
     // private bool _stopped;
-    private Vector3 _size;
-    private Vector3 _scale;
+    private OMV.Vector3 _size;
+    private OMV.Vector3 _scale;
     private PrimitiveBaseShape _pbs;
-    private uint _localID = 0;
     private bool _grabbed;
     private bool _selected;
-    private Vector3 _position;
+    private OMV.Vector3 _position;
     private float _mass;
-    public float _density;
-    public float _avatarVolume;
-    private Vector3 _force;
-    private Vector3 _velocity;
-    private Vector3 _torque;
+    private float _avatarDensity;
+    private float _avatarVolume;
+    private OMV.Vector3 _force;
+    private OMV.Vector3 _velocity;
+    private OMV.Vector3 _torque;
     private float _collisionScore;
-    private Vector3 _acceleration;
-    private Quaternion _orientation;
+    private OMV.Vector3 _acceleration;
+    private OMV.Quaternion _orientation;
     private int _physicsActorType;
     private bool _isPhysical;
     private bool _flying;
     private bool _setAlwaysRun;
     private bool _throttleUpdates;
     private bool _isColliding;
-    private long _collidingStep;
-    private bool _collidingGround;
-    private long _collidingGroundStep;
     private bool _collidingObj;
     private bool _floatOnWater;
-    private Vector3 _rotationalVelocity;
+    private OMV.Vector3 _rotationalVelocity;
     private bool _kinematic;
     private float _buoyancy;
 
-    public override BulletBody BSBody { get; set; }
-    public override BulletShape BSShape { get; set; }
-    public override BSLinkset Linkset { get; set; }
-
-    private int _subscribedEventsMs = 0;
-    private int _nextCollisionOkTime = 0;
-
-    private Vector3 _PIDTarget;
+    private OMV.Vector3 _PIDTarget;
     private bool _usePID;
     private float _PIDTau;
     private bool _useHoverPID;
@@ -88,28 +75,26 @@ public class BSCharacter : BSPhysObject
     private PIDHoverType _PIDHoverType;
     private float _PIDHoverTao;
 
-    public BSCharacter(uint localID, String avName, BSScene parent_scene, Vector3 pos, Vector3 size, bool isFlying)
+    public BSCharacter(uint localID, String avName, BSScene parent_scene, OMV.Vector3 pos, OMV.Vector3 size, bool isFlying)
     {
-        _localID = localID;
-        _avName = avName;
-        Scene = parent_scene;
+        base.BaseInitialize(parent_scene, localID, avName, "BSCharacter");
         _physicsActorType = (int)ActorTypes.Agent;
         _position = pos;
         _size = size;
         _flying = isFlying;
-        _orientation = Quaternion.Identity;
-        _velocity = Vector3.Zero;
+        _orientation = OMV.Quaternion.Identity;
+        _velocity = OMV.Vector3.Zero;
         _buoyancy = ComputeBuoyancyFromFlying(isFlying);
+
         // The dimensions of the avatar capsule are kept in the scale.
         // Physics creates a unit capsule which is scaled by the physics engine.
-        _scale = new Vector3(Scene.Params.avatarCapsuleRadius, Scene.Params.avatarCapsuleRadius, size.Z);
-        _density = Scene.Params.avatarDensity;
-        ComputeAvatarVolumeAndMass();   // set _avatarVolume and _mass based on capsule size, _density and _scale
-
-        Linkset = new BSLinkset(Scene, this);
+        ComputeAvatarScale(_size);
+        _avatarDensity = PhysicsScene.Params.avatarDensity;
+        // set _avatarVolume and _mass based on capsule size, _density and _scale
+        ComputeAvatarVolumeAndMass();
 
         ShapeData shapeData = new ShapeData();
-        shapeData.ID = _localID;
+        shapeData.ID = LocalID;
         shapeData.Type = ShapeData.PhysicsShapeType.SHAPE_AVATAR;
         shapeData.Position = _position;
         shapeData.Rotation = _orientation;
@@ -118,21 +103,25 @@ public class BSCharacter : BSPhysObject
         shapeData.Mass = _mass;
         shapeData.Buoyancy = _buoyancy;
         shapeData.Static = ShapeData.numericFalse;
-        shapeData.Friction = Scene.Params.avatarFriction;
-        shapeData.Restitution = Scene.Params.avatarRestitution;
+        shapeData.Friction = PhysicsScene.Params.avatarFriction;
+        shapeData.Restitution = PhysicsScene.Params.avatarRestitution;
 
         // do actual create at taint time
-        Scene.TaintedObject("BSCharacter.create", delegate()
+        PhysicsScene.TaintedObject("BSCharacter.create", delegate()
         {
-            DetailLog("{0},BSCharacter.create", _localID);
-            BulletSimAPI.CreateObject(Scene.WorldID, shapeData);
+            DetailLog("{0},BSCharacter.create,taint", LocalID);
+            BulletSimAPI.CreateObject(PhysicsScene.WorldID, shapeData);
 
-            // Set the buoyancy for flying. This will be refactored when all the settings happen in C#
-            BulletSimAPI.SetObjectBuoyancy(Scene.WorldID, LocalID, _buoyancy);
+            // Set the buoyancy for flying. This will be refactored when all the settings happen in C#.
+            // If not set at creation, the avatar will stop flying when created after crossing a region boundry.
+            BulletSimAPI.SetObjectBuoyancy(PhysicsScene.WorldID, LocalID, _buoyancy);
 
-            BSBody = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(Scene.World.Ptr, LocalID));
+            BSBody = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(PhysicsScene.World.ptr, LocalID));
+
+            // This works here because CreateObject has already put the character into the physical world.
+            BulletSimAPI.SetCollisionFilterMask2(BSBody.ptr,
+                            (uint)CollisionFilterGroups.AvatarFilter, (uint)CollisionFilterGroups.AvatarMask);
         });
-            
         return;
     }
 
@@ -140,9 +129,9 @@ public class BSCharacter : BSPhysObject
     public override void Destroy()
     {
         DetailLog("{0},BSCharacter.Destroy", LocalID);
-        Scene.TaintedObject("BSCharacter.destroy", delegate()
+        PhysicsScene.TaintedObject("BSCharacter.destroy", delegate()
         {
-            BulletSimAPI.DestroyObject(Scene.WorldID, _localID);
+            BulletSimAPI.DestroyObject(PhysicsScene.WorldID, LocalID);
         });
     }
 
@@ -151,70 +140,83 @@ public class BSCharacter : BSPhysObject
         base.RequestPhysicsterseUpdate();
     }
     // No one calls this method so I don't know what it could possibly mean
-    public override bool Stopped { 
-        get { return false; } 
+    public override bool Stopped {
+        get { return false; }
     }
-    public override Vector3 Size {
+    public override OMV.Vector3 Size {
         get
         {
             // Avatar capsule size is kept in the scale parameter.
-            return new Vector3(_scale.X * 2, _scale.Y * 2, _scale.Z);
+            return new OMV.Vector3(_scale.X * 2, _scale.Y * 2, _scale.Z);
         }
 
-        set { 
+        set {
             // When an avatar's size is set, only the height is changed
             //    and that really only depends on the radius.
             _size = value;
-            _scale.Z = (_size.Z * 1.15f) - (_scale.X + _scale.Y);
+            ComputeAvatarScale(_size);
 
             // TODO: something has to be done with the avatar's vertical position
 
             ComputeAvatarVolumeAndMass();
 
-            Scene.TaintedObject("BSCharacter.setSize", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.setSize", delegate()
             {
-                BulletSimAPI.SetObjectScaleMass(Scene.WorldID, LocalID, _scale, _mass, true);
+                BulletSimAPI.SetObjectScaleMass(PhysicsScene.WorldID, LocalID, _scale, _mass, true);
             });
 
-        } 
-    }
-    public override PrimitiveBaseShape Shape { 
-        set { _pbs = value; 
-        } 
+        }
     }
-    public override uint LocalID { 
-        set { _localID = value; 
+    public override PrimitiveBaseShape Shape {
+        set { _pbs = value;
         }
-        get { return _localID; }
     }
-    public override bool Grabbed { 
-        set { _grabbed = value; 
-        } 
+    public override bool Grabbed {
+        set { _grabbed = value;
+        }
     }
-    public override bool Selected { 
-        set { _selected = value; 
-        } 
+    public override bool Selected {
+        set { _selected = value;
+        }
     }
     public override void CrossingFailure() { return; }
     public override void link(PhysicsActor obj) { return; }
     public override void delink() { return; }
-    public override void LockAngularMotion(Vector3 axis) { return; }
 
-    public override Vector3 Position { 
+    // Set motion values to zero.
+    // Do it to the properties so the values get set in the physics engine.
+    // Push the setting of the values to the viewer.
+    // Called at taint time!
+    public override void ZeroMotion()
+    {
+        _velocity = OMV.Vector3.Zero;
+        _acceleration = OMV.Vector3.Zero;
+        _rotationalVelocity = OMV.Vector3.Zero;
+
+        // Zero some other properties directly into the physics engine
+        BulletSimAPI.SetLinearVelocity2(BSBody.ptr, OMV.Vector3.Zero);
+        BulletSimAPI.SetAngularVelocity2(BSBody.ptr, OMV.Vector3.Zero);
+        BulletSimAPI.SetInterpolationVelocity2(BSBody.ptr, OMV.Vector3.Zero, OMV.Vector3.Zero);
+        BulletSimAPI.ClearForces2(BSBody.ptr);
+    }
+
+    public override void LockAngularMotion(OMV.Vector3 axis) { return; }
+
+    public override OMV.Vector3 Position {
         get {
             // _position = BulletSimAPI.GetObjectPosition(Scene.WorldID, _localID);
-            return _position; 
-        } 
+            return _position;
+        }
         set {
             _position = value;
             PositionSanityCheck();
 
-            Scene.TaintedObject("BSCharacter.setPosition", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.setPosition", delegate()
             {
                 DetailLog("{0},BSCharacter.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetObjectTranslation(Scene.WorldID, _localID, _position, _orientation);
+                BulletSimAPI.SetObjectTranslation(PhysicsScene.WorldID, LocalID, _position, _orientation);
             });
-        } 
+        }
     }
 
     // Check that the current position is sane and, if not, modify the position to make it so.
@@ -223,9 +225,9 @@ public class BSCharacter : BSPhysObject
     private bool PositionSanityCheck()
     {
         bool ret = false;
-        
+      
         // If below the ground, move the avatar up
-        float terrainHeight = Scene.TerrainManager.GetTerrainHeightAtXYZ(_position);
+        float terrainHeight = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(_position);
         if (Position.Z < terrainHeight)
         {
             DetailLog("{0},BSCharacter.PositionAdjustUnderGround,call,pos={1},terrain={2}", LocalID, _position, terrainHeight);
@@ -247,200 +249,200 @@ public class BSCharacter : BSPhysObject
         {
             // The new position value must be pushed into the physics engine but we can't
             //    just assign to "Position" because of potential call loops.
-            Scene.TaintedObject("BSCharacter.PositionSanityCheck", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.PositionSanityCheck", delegate()
             {
                 DetailLog("{0},BSCharacter.PositionSanityCheck,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetObjectTranslation(Scene.WorldID, _localID, _position, _orientation);
+                BulletSimAPI.SetObjectTranslation(PhysicsScene.WorldID, LocalID, _position, _orientation);
             });
             ret = true;
         }
         return ret;
     }
 
-    public override float Mass { 
-        get { 
-            return _mass; 
-        } 
+    public override float Mass {
+        get {
+            return _mass;
+        }
     }
 
     // used when we only want this prim's mass and not the linkset thing
     public override float MassRaw { get {return _mass; } }
 
-    public override Vector3 Force { 
-        get { return _force; } 
+    public override OMV.Vector3 Force {
+        get { return _force; }
         set {
             _force = value;
             // m_log.DebugFormat("{0}: Force = {1}", LogHeader, _force);
-            Scene.TaintedObject("BSCharacter.SetForce", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.SetForce", delegate()
             {
                 DetailLog("{0},BSCharacter.setForce,taint,force={1}", LocalID, _force);
-                BulletSimAPI.SetObjectForce(Scene.WorldID, LocalID, _force);
+                BulletSimAPI.SetObjectForce(PhysicsScene.WorldID, LocalID, _force);
             });
-        } 
+        }
     }
 
-    public override int VehicleType { 
-        get { return 0; } 
-        set { return; } 
+    public override int VehicleType {
+        get { return 0; }
+        set { return; }
     }
     public override void VehicleFloatParam(int param, float value) { }
-    public override void VehicleVectorParam(int param, Vector3 value) {}
-    public override void VehicleRotationParam(int param, Quaternion rotation) { }
+    public override void VehicleVectorParam(int param, OMV.Vector3 value) {}
+    public override void VehicleRotationParam(int param, OMV.Quaternion rotation) { }
     public override void VehicleFlags(int param, bool remove) { }
 
     // Allows the detection of collisions with inherently non-physical prims. see llVolumeDetect for more
     public override void SetVolumeDetect(int param) { return; }
 
-    public override Vector3 GeometricCenter { get { return Vector3.Zero; } }
-    public override Vector3 CenterOfMass { get { return Vector3.Zero; } }
-    public override Vector3 Velocity { 
-        get { return _velocity; } 
+    public override OMV.Vector3 GeometricCenter { get { return OMV.Vector3.Zero; } }
+    public override OMV.Vector3 CenterOfMass { get { return OMV.Vector3.Zero; } }
+    public override OMV.Vector3 Velocity {
+        get { return _velocity; }
         set {
             _velocity = value;
             // m_log.DebugFormat("{0}: set velocity = {1}", LogHeader, _velocity);
-            Scene.TaintedObject("BSCharacter.setVelocity", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.setVelocity", delegate()
             {
                 DetailLog("{0},BSCharacter.setVelocity,taint,vel={1}", LocalID, _velocity);
-                BulletSimAPI.SetObjectVelocity(Scene.WorldID, _localID, _velocity);
+                BulletSimAPI.SetObjectVelocity(PhysicsScene.WorldID, LocalID, _velocity);
             });
-        } 
+        }
     }
-    public override Vector3 Torque { 
-        get { return _torque; } 
-        set { _torque = value; 
-        } 
+    public override OMV.Vector3 Torque {
+        get { return _torque; }
+        set { _torque = value;
+        }
     }
-    public override float CollisionScore { 
-        get { return _collisionScore; } 
-        set { _collisionScore = value; 
-        } 
+    public override float CollisionScore {
+        get { return _collisionScore; }
+        set { _collisionScore = value;
+        }
     }
-    public override Vector3 Acceleration { 
+    public override OMV.Vector3 Acceleration {
         get { return _acceleration; }
         set { _acceleration = value; }
     }
-    public override Quaternion Orientation { 
-        get { return _orientation; } 
+    public override OMV.Quaternion Orientation {
+        get { return _orientation; }
         set {
             _orientation = value;
             // m_log.DebugFormat("{0}: set orientation to {1}", LogHeader, _orientation);
-            Scene.TaintedObject("BSCharacter.setOrientation", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.setOrientation", delegate()
             {
                 // _position = BulletSimAPI.GetObjectPosition(Scene.WorldID, _localID);
-                BulletSimAPI.SetObjectTranslation(Scene.WorldID, _localID, _position, _orientation);
+                BulletSimAPI.SetObjectTranslation(PhysicsScene.WorldID, LocalID, _position, _orientation);
             });
-        } 
+        }
     }
-    public override int PhysicsActorType { 
-        get { return _physicsActorType; } 
-        set { _physicsActorType = value; 
-        } 
+    public override int PhysicsActorType {
+        get { return _physicsActorType; }
+        set { _physicsActorType = value;
+        }
     }
-    public override bool IsPhysical { 
-        get { return _isPhysical; } 
+    public override bool IsPhysical {
+        get { return _isPhysical; }
         set { _isPhysical = value;
-        } 
+        }
     }
-    public override bool Flying { 
-        get { return _flying; } 
+    public override bool Flying {
+        get { return _flying; }
         set {
             _flying = value;
             // simulate flying by changing the effect of gravity
             this.Buoyancy = ComputeBuoyancyFromFlying(_flying);
-        } 
+        }
     }
     // Flying is implimented by changing the avatar's buoyancy.
     // Would this be done better with a vehicle type?
     private float ComputeBuoyancyFromFlying(bool ifFlying) {
         return ifFlying ? 1f : 0f;
     }
-    public override bool 
-        SetAlwaysRun { 
-        get { return _setAlwaysRun; } 
-        set { _setAlwaysRun = value; } 
+    public override bool
+        SetAlwaysRun {
+        get { return _setAlwaysRun; }
+        set { _setAlwaysRun = value; }
     }
-    public override bool ThrottleUpdates { 
-        get { return _throttleUpdates; } 
-        set { _throttleUpdates = value; } 
+    public override bool ThrottleUpdates {
+        get { return _throttleUpdates; }
+        set { _throttleUpdates = value; }
     }
     public override bool IsColliding {
-        get { return (_collidingStep == Scene.SimulationStep); } 
-        set { _isColliding = value; } 
+        get { return (CollidingStep == PhysicsScene.SimulationStep); }
+        set { _isColliding = value; }
     }
     public override bool CollidingGround {
-        get { return (_collidingGroundStep == Scene.SimulationStep); } 
-        set { _collidingGround = value; } 
+        get { return (CollidingGroundStep == PhysicsScene.SimulationStep); }
+        set { CollidingGround = value; }
     }
-    public override bool CollidingObj { 
-        get { return _collidingObj; } 
-        set { _collidingObj = value; } 
+    public override bool CollidingObj {
+        get { return _collidingObj; }
+        set { _collidingObj = value; }
     }
-    public override bool FloatOnWater { 
-        set { _floatOnWater = value; } 
+    public override bool FloatOnWater {
+        set { _floatOnWater = value; }
     }
-    public override Vector3 RotationalVelocity { 
-        get { return _rotationalVelocity; } 
-        set { _rotationalVelocity = value; } 
+    public override OMV.Vector3 RotationalVelocity {
+        get { return _rotationalVelocity; }
+        set { _rotationalVelocity = value; }
     }
-    public override bool Kinematic { 
-        get { return _kinematic; } 
-        set { _kinematic = value; } 
+    public override bool Kinematic {
+        get { return _kinematic; }
+        set { _kinematic = value; }
     }
     // neg=fall quickly, 0=1g, 1=0g, pos=float up
-    public override float Buoyancy { 
-        get { return _buoyancy; } 
-        set { _buoyancy = value; 
-            Scene.TaintedObject("BSCharacter.setBuoyancy", delegate()
+    public override float Buoyancy {
+        get { return _buoyancy; }
+        set { _buoyancy = value;
+            PhysicsScene.TaintedObject("BSCharacter.setBuoyancy", delegate()
             {
                 DetailLog("{0},BSCharacter.setBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
-                BulletSimAPI.SetObjectBuoyancy(Scene.WorldID, LocalID, _buoyancy);
+                BulletSimAPI.SetObjectBuoyancy(PhysicsScene.WorldID, LocalID, _buoyancy);
             });
-        } 
+        }
     }
 
     // Used for MoveTo
-    public override Vector3 PIDTarget { 
-        set { _PIDTarget = value; } 
+    public override OMV.Vector3 PIDTarget {
+        set { _PIDTarget = value; }
     }
-    public override bool PIDActive { 
-        set { _usePID = value; } 
+    public override bool PIDActive {
+        set { _usePID = value; }
     }
-    public override float PIDTau { 
-        set { _PIDTau = value; } 
+    public override float PIDTau {
+        set { _PIDTau = value; }
     }
 
     // Used for llSetHoverHeight and maybe vehicle height
     // Hover Height will override MoveTo target's Z
-    public override bool PIDHoverActive { 
+    public override bool PIDHoverActive {
         set { _useHoverPID = value; }
     }
-    public override float PIDHoverHeight { 
+    public override float PIDHoverHeight {
         set { _PIDHoverHeight = value; }
     }
-    public override PIDHoverType PIDHoverType { 
+    public override PIDHoverType PIDHoverType {
         set { _PIDHoverType = value; }
     }
-    public override float PIDHoverTau { 
+    public override float PIDHoverTau {
         set { _PIDHoverTao = value; }
     }
 
     // For RotLookAt
-    public override Quaternion APIDTarget { set { return; } }
+    public override OMV.Quaternion APIDTarget { set { return; } }
     public override bool APIDActive { set { return; } }
     public override float APIDStrength { set { return; } }
     public override float APIDDamping { set { return; } }
 
-    public override void AddForce(Vector3 force, bool pushforce) { 
+    public override void AddForce(OMV.Vector3 force, bool pushforce) {
         if (force.IsFinite())
         {
             _force.X += force.X;
             _force.Y += force.Y;
             _force.Z += force.Z;
             // m_log.DebugFormat("{0}: AddForce. adding={1}, newForce={2}", LogHeader, force, _force);
-            Scene.TaintedObject("BSCharacter.AddForce", delegate()
+            PhysicsScene.TaintedObject("BSCharacter.AddForce", delegate()
             {
                 DetailLog("{0},BSCharacter.setAddForce,taint,addedForce={1}", LocalID, _force);
-                BulletSimAPI.SetObjectForce2(BSBody.Ptr, _force);
+                BulletSimAPI.SetObjectForce2(BSBody.ptr, _force);
             });
         }
         else
@@ -450,42 +452,19 @@ public class BSCharacter : BSPhysObject
         //m_lastUpdateSent = false;
     }
 
-    public override void AddAngularForce(Vector3 force, bool pushforce) { 
+    public override void AddAngularForce(OMV.Vector3 force, bool pushforce) {
     }
-    public override void SetMomentum(Vector3 momentum) { 
+    public override void SetMomentum(OMV.Vector3 momentum) {
     }
 
-    // Turn on collision events at a rate no faster than one every the given milliseconds
-    public override void SubscribeEvents(int ms) {
-        _subscribedEventsMs = ms;
-        if (ms > 0)
-        {
-            // make sure first collision happens
-            _nextCollisionOkTime = Util.EnvironmentTickCount() - _subscribedEventsMs;
-
-            Scene.TaintedObject("BSCharacter.SubscribeEvents", delegate()
-            {
-                BulletSimAPI.AddToCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
-            });
-        }
-    }
-
-    public override void ZeroMotion()
+    private void ComputeAvatarScale(OMV.Vector3 size)
     {
-        return;
-    }
+        _scale.X = PhysicsScene.Params.avatarCapsuleRadius;
+        _scale.Y = PhysicsScene.Params.avatarCapsuleRadius;
 
-    // Stop collision events
-    public override void UnSubscribeEvents() { 
-        _subscribedEventsMs = 0;
-        Scene.TaintedObject("BSCharacter.UnSubscribeEvents", delegate()
-        {
-            BulletSimAPI.RemoveFromCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
-        });
-    }
-    // Return 'true' if someone has subscribed to events
-    public override bool SubscribedEvents() {
-        return (_subscribedEventsMs > 0);
+        // The 1.15 came from ODE but it seems to cause the avatar to float off the ground
+        // _scale.Z = (_size.Z * 1.15f) - (_scale.X + _scale.Y);
+        _scale.Z = (_size.Z) - (_scale.X + _scale.Y);
     }
 
     // set _avatarVolume and _mass based on capsule size, _density and _scale
@@ -502,7 +481,7 @@ public class BSCharacter : BSPhysObject
                         * Math.Min(_scale.X, _scale.Y)
                         * _scale.Y  // plus the volume of the capsule end caps
                         );
-        _mass = _density * _avatarVolume;
+        _mass = _avatarDensity * _avatarVolume;
     }
 
     // The physics engine says that properties have updated. Update same and inform
@@ -520,67 +499,9 @@ public class BSCharacter : BSPhysObject
         // Do some sanity checking for the avatar. Make sure it's above ground and inbounds.
         PositionSanityCheck2();
 
-        float heightHere = Scene.TerrainManager.GetTerrainHeightAtXYZ(_position);   // only for debug
+        float heightHere = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(_position);   // only for debug
         DetailLog("{0},BSCharacter.UpdateProperties,call,pos={1},orient={2},vel={3},accel={4},rotVel={5},terrain={6}",
                 LocalID, _position, _orientation, _velocity, _acceleration, _rotationalVelocity, heightHere);
     }
-
-    // Called by the scene when a collision with this object is reported
-    // The collision, if it should be reported to the character, is placed in a collection
-    //   that will later be sent to the simulator when SendCollisions() is called.
-    CollisionEventUpdate collisionCollection = null;
-    public override bool Collide(uint collidingWith, BSPhysObject collidee, Vector3 contactPoint, Vector3 contactNormal, float pentrationDepth)
-    {
-        bool ret = false;
-
-        // The following makes IsColliding() and IsCollidingGround() work
-        _collidingStep = Scene.SimulationStep;
-        if (collidingWith <= Scene.TerrainManager.HighestTerrainID)
-        {
-            _collidingGroundStep = Scene.SimulationStep;
-        }
-        // DetailLog("{0},BSCharacter.Collison,call,with={1}", LocalID, collidingWith);
-
-        // throttle collisions to the rate specified in the subscription
-        if (SubscribedEvents()) {
-            int nowTime = Scene.SimulationNowTime;
-            if (nowTime >= _nextCollisionOkTime) {
-                _nextCollisionOkTime = nowTime + _subscribedEventsMs;
-
-                if (collisionCollection == null)
-                    collisionCollection = new CollisionEventUpdate();
-                collisionCollection.AddCollider(collidingWith, new ContactPoint(contactPoint, contactNormal, pentrationDepth));
-                ret = true;
-            }
-        }
-        return ret;
-    }
-
-    public override void SendCollisions()
-    {
-        /*
-        if (collisionCollection != null && collisionCollection.Count > 0)
-        {
-            base.SendCollisionUpdate(collisionCollection);
-            collisionCollection = null;
-        }
-         */
-        // Kludge to make a collision call even if there are no collisions.
-        // This causes the avatar animation to get updated.
-        if (collisionCollection == null)
-            collisionCollection = new CollisionEventUpdate();
-        base.SendCollisionUpdate(collisionCollection);
-        // If there were any collisions in the collection, make sure we don't use the
-        //    same instance next time.
-        if (collisionCollection.Count > 0)
-            collisionCollection = null;
-        // End kludge
-    }
-
-    // Invoke the detailed logger and output something if it's enabled.
-    private void DetailLog(string msg, params Object[] args)
-    {
-        Scene.PhysicsLogging.Write(msg, args);
-    }
 }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
index 1376a29..63a4127 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
@@ -49,20 +49,23 @@ public abstract class BSConstraint : IDisposable
         if (m_enabled)
         {
             m_enabled = false;
-            bool success = BulletSimAPI.DestroyConstraint2(m_world.Ptr, m_constraint.Ptr);
-            m_world.scene.DetailLog("{0},BSConstraint.Dispose,taint,body1={1},body2={2},success={3}", BSScene.DetailLogZero, m_body1.ID, m_body2.ID, success);
-            m_constraint.Ptr = System.IntPtr.Zero;
+            bool success = BulletSimAPI.DestroyConstraint2(m_world.ptr, m_constraint.ptr);
+            m_world.physicsScene.DetailLog("{0},BSConstraint.Dispose,taint,body1={1},body2={2},success={3}", BSScene.DetailLogZero, m_body1.ID, m_body2.ID, success);
+            m_constraint.ptr = System.IntPtr.Zero;
         }
     }
 
     public BulletBody Body1 { get { return m_body1; } }
     public BulletBody Body2 { get { return m_body2; } }
+    public BulletConstraint Constraint { get { return m_constraint; } }
+    public abstract ConstraintType Type { get; }
+
 
     public virtual bool SetLinearLimits(Vector3 low, Vector3 high)
     {
         bool ret = false;
         if (m_enabled)
-            ret = BulletSimAPI.SetLinearLimits2(m_constraint.Ptr, low, high);
+            ret = BulletSimAPI.SetLinearLimits2(m_constraint.ptr, low, high);
         return ret;
     }
 
@@ -70,7 +73,7 @@ public abstract class BSConstraint : IDisposable
     {
         bool ret = false;
         if (m_enabled)
-            ret = BulletSimAPI.SetAngularLimits2(m_constraint.Ptr, low, high);
+            ret = BulletSimAPI.SetAngularLimits2(m_constraint.ptr, low, high);
         return ret;
     }
 
@@ -79,7 +82,7 @@ public abstract class BSConstraint : IDisposable
         bool ret = false;
         if (m_enabled)
         {
-            BulletSimAPI.SetConstraintNumSolverIterations2(m_constraint.Ptr, cnt);
+            BulletSimAPI.SetConstraintNumSolverIterations2(m_constraint.ptr, cnt);
             ret = true;
         }
         return ret;
@@ -91,7 +94,7 @@ public abstract class BSConstraint : IDisposable
         if (m_enabled)
         {
             // Recompute the internal transforms
-            BulletSimAPI.CalculateTransforms2(m_constraint.Ptr);
+            BulletSimAPI.CalculateTransforms2(m_constraint.ptr);
             ret = true;
         }
         return ret;
@@ -110,11 +113,11 @@ public abstract class BSConstraint : IDisposable
                 // Setting an object's mass to zero (making it static like when it's selected)
                 //     automatically disables the constraints.
                 // If the link is enabled, be sure to set the constraint itself to enabled.
-                BulletSimAPI.SetConstraintEnable2(m_constraint.Ptr, m_world.scene.NumericBool(true));
+                BulletSimAPI.SetConstraintEnable2(m_constraint.ptr, m_world.physicsScene.NumericBool(true));
             }
             else
             {
-                m_world.scene.Logger.ErrorFormat("[BULLETSIM CONSTRAINT] CalculateTransforms failed. A={0}, B={1}", Body1.ID, Body2.ID);
+                m_world.physicsScene.Logger.ErrorFormat("[BULLETSIM CONSTRAINT] CalculateTransforms failed. A={0}, B={1}", Body1.ID, Body2.ID);
             }
         }
         return ret;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
index 61006f0..65b38d6 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
@@ -54,18 +54,13 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 {
     public class BSDynamics
     {
-        private int frcount = 0;                                        // Used to limit dynamics debug output to
-                                                                        // every 100th frame
-
-        private BSScene m_physicsScene;
-        private BSPrim m_prim;      // the prim this dynamic controller belongs to
+        private BSScene PhysicsScene { get; set; }
+        // the prim this dynamic controller belongs to
+        private BSPrim Prim { get; set; }
 
         // Vehicle properties
-        private Vehicle m_type = Vehicle.TYPE_NONE;                     // If a 'VEHICLE', and what kind
-        public Vehicle Type
-        {
-            get { return m_type; }
-        }
+        public Vehicle Type { get; set; }
+
         // private Quaternion m_referenceFrame = Quaternion.Identity;   // Axis modifier
         private VehicleFlag m_flags = (VehicleFlag) 0;                  // Boolean settings:
                                                                         // HOVER_TERRAIN_ONLY
@@ -126,14 +121,20 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
         public BSDynamics(BSScene myScene, BSPrim myPrim)
         {
-            m_physicsScene = myScene;
-            m_prim = myPrim;
-            m_type = Vehicle.TYPE_NONE;
+            PhysicsScene = myScene;
+            Prim = myPrim;
+            Type = Vehicle.TYPE_NONE;
+        }
+
+        // Return 'true' if this vehicle is doing vehicle things
+        public bool IsActive
+        {
+            get { return Type != Vehicle.TYPE_NONE; }
         }
 
         internal void ProcessFloatVehicleParam(Vehicle pParam, float pValue)
         {
-            VDetailLog("{0},ProcessFloatVehicleParam,param={1},val={2}", m_prim.LocalID, pParam, pValue);
+            VDetailLog("{0},ProcessFloatVehicleParam,param={1},val={2}", Prim.LocalID, pParam, pValue);
             switch (pParam)
             {
                 case Vehicle.ANGULAR_DEFLECTION_EFFICIENCY:
@@ -232,7 +233,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
         internal void ProcessVectorVehicleParam(Vehicle pParam, Vector3 pValue)
         {
-            VDetailLog("{0},ProcessVectorVehicleParam,param={1},val={2}", m_prim.LocalID, pParam, pValue);
+            VDetailLog("{0},ProcessVectorVehicleParam,param={1},val={2}", Prim.LocalID, pParam, pValue);
             switch (pParam)
             {
                 case Vehicle.ANGULAR_FRICTION_TIMESCALE:
@@ -267,7 +268,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
         internal void ProcessRotationVehicleParam(Vehicle pParam, Quaternion pValue)
         {
-            VDetailLog("{0},ProcessRotationalVehicleParam,param={1},val={2}", m_prim.LocalID, pParam, pValue);
+            VDetailLog("{0},ProcessRotationalVehicleParam,param={1},val={2}", Prim.LocalID, pParam, pValue);
             switch (pParam)
             {
                 case Vehicle.REFERENCE_FRAME:
@@ -281,7 +282,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
         internal void ProcessVehicleFlags(int pParam, bool remove)
         {
-            VDetailLog("{0},ProcessVehicleFlags,param={1},remove={2}", m_prim.LocalID, pParam, remove);
+            VDetailLog("{0},ProcessVehicleFlags,param={1},remove={2}", Prim.LocalID, pParam, remove);
             VehicleFlag parm = (VehicleFlag)pParam;
             if (remove)
             {
@@ -301,9 +302,9 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
         internal void ProcessTypeChange(Vehicle pType)
         {
-            VDetailLog("{0},ProcessTypeChange,type={1}", m_prim.LocalID, pType);
+            VDetailLog("{0},ProcessTypeChange,type={1}", Prim.LocalID, pType);
             // Set Defaults For Type
-            m_type = pType;
+            Type = pType;
             switch (pType)
             {
                     case Vehicle.TYPE_NONE:
@@ -465,26 +466,37 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             }
         }//end SetDefaultsForType
 
+        // Some of the properties of this prim may have changed.
+        // Do any updating needed for a vehicle
+        public void Refresh()
+        {
+            if (Type == Vehicle.TYPE_NONE) return;
+
+            // Set the prim's inertia to zero. The vehicle code handles that and this
+            //    removes the torque action introduced by Bullet.
+            Vector3 inertia = Vector3.Zero;
+            BulletSimAPI.SetMassProps2(Prim.BSBody.ptr, Prim.MassRaw, inertia);
+            BulletSimAPI.UpdateInertiaTensor2(Prim.BSBody.ptr);
+        }
+
         // One step of the vehicle properties for the next 'pTimestep' seconds.
         internal void Step(float pTimestep)
         {
-            if (m_type == Vehicle.TYPE_NONE) return;
-
-            frcount++;  // used to limit debug comment output
-            if (frcount > 100)
-                frcount = 0;
+            if (!IsActive) return;
 
             MoveLinear(pTimestep);
             MoveAngular(pTimestep);
             LimitRotation(pTimestep);
 
             // remember the position so next step we can limit absolute movement effects
-            m_lastPositionVector = m_prim.Position;
+            m_lastPositionVector = Prim.Position;
 
-            VDetailLog("{0},BSDynamics.Step,done,pos={1},force={2},velocity={3},angvel={4}", 
-                    m_prim.LocalID, m_prim.Position, m_prim.Force, m_prim.Velocity, m_prim.RotationalVelocity);
+            VDetailLog("{0},BSDynamics.Step,done,pos={1},force={2},velocity={3},angvel={4}",
+                    Prim.LocalID, Prim.Position, Prim.Force, Prim.Velocity, 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 direction we are moving relative to the vehicle coordinates
@@ -499,8 +511,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 Vector3 addAmount = (m_linearMotorDirection - m_lastLinearVelocityVector)/(m_linearMotorTimescale / pTimestep);
                 // lastLinearVelocityVector is the current body velocity vector
                 // RA: Not sure what the *10 is for. A correction for pTimestep?
-                // m_lastLinearVelocityVector += (addAmount*10);  
-                m_lastLinearVelocityVector += addAmount;  
+                // m_lastLinearVelocityVector += (addAmount*10);
+                m_lastLinearVelocityVector += addAmount;
 
                 // Limit the velocity vector to less than the last set linear motor direction
                 if (Math.Abs(m_lastLinearVelocityVector.X) > Math.Abs(m_linearMotorDirectionLASTSET.X))
@@ -520,18 +532,18 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 m_linearMotorDirection *= keepfraction;
 
                 VDetailLog("{0},MoveLinear,nonZero,origdir={1},origvel={2},add={3},notDecay={4},dir={5},vel={6}",
-                    m_prim.LocalID, origDir, origVel, addAmount, keepfraction, m_linearMotorDirection, m_lastLinearVelocityVector);
+                    Prim.LocalID, origDir, origVel, addAmount, keepfraction, m_linearMotorDirection, m_lastLinearVelocityVector);
             }
             else
             {
                 // if what remains of direction is very small, zero it.
                 m_linearMotorDirection = Vector3.Zero;
                 m_lastLinearVelocityVector = Vector3.Zero;
-                VDetailLog("{0},MoveLinear,zeroed", m_prim.LocalID);
+                VDetailLog("{0},MoveLinear,zeroed", Prim.LocalID);
             }
 
             // convert requested object velocity to object relative vector
-            Quaternion rotq = m_prim.Orientation;
+            Quaternion rotq = Prim.Orientation;
             m_newVelocity = m_lastLinearVelocityVector * rotq;
 
             // Add the various forces into m_dir which will be our new direction vector (velocity)
@@ -539,7 +551,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             // add 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 = m_prim.Scene.DefaultGravity * (m_prim.Mass * (1f - m_VehicleBuoyancy));
+            Vector3 grav = Prim.PhysicsScene.DefaultGravity * (Prim.Mass * (1f - m_VehicleBuoyancy));
 
             /*
              * RA: Not sure why one would do this
@@ -548,11 +560,11 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             m_dir.Z = vel_now.Z;        // Preserve the accumulated falling velocity
              */
 
-            Vector3 pos = m_prim.Position;
+            Vector3 pos = Prim.Position;
 //            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);
 
             // If below the terrain, move us above the ground a little.
-            float terrainHeight = m_prim.Scene.TerrainManager.GetTerrainHeightAtXYZ(pos);
+            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.
             //     Need to add a m_prim.LinkSet.Size similar to m_prim.LinkSet.Mass.
             // Vector3 rotatedSize = m_prim.Size * m_prim.Orientation;
@@ -560,8 +572,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             if (pos.Z < terrainHeight)
             {
                 pos.Z = terrainHeight + 2;
-                m_prim.Position = pos;
-                VDetailLog("{0},MoveLinear,terrainHeight,terrainHeight={1},pos={2}", m_prim.LocalID, terrainHeight, pos);
+                Prim.Position = pos;
+                VDetailLog("{0},MoveLinear,terrainHeight,terrainHeight={1},pos={2}", Prim.LocalID, terrainHeight, pos);
             }
 
             // Check if hovering
@@ -570,7 +582,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 // We should hover, get the target height
                 if ((m_flags & VehicleFlag.HOVER_WATER_ONLY) != 0)
                 {
-                    m_VhoverTargetHeight = m_prim.Scene.GetWaterLevelAtXYZ(pos) + m_VhoverHeight;
+                    m_VhoverTargetHeight = Prim.PhysicsScene.GetWaterLevelAtXYZ(pos) + m_VhoverHeight;
                 }
                 if ((m_flags & VehicleFlag.HOVER_TERRAIN_ONLY) != 0)
                 {
@@ -590,7 +602,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 {
                     if ((pos.Z - m_VhoverTargetHeight) > .2 || (pos.Z - m_VhoverTargetHeight) < -.2)
                     {
-                        m_prim.Position = pos;
+                        Prim.Position = pos;
                     }
                 }
                 else
@@ -608,7 +620,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                     }
                 }
 
-                VDetailLog("{0},MoveLinear,hover,pos={1},dir={2},height={3},target={4}", m_prim.LocalID, pos, m_newVelocity, m_VhoverHeight, m_VhoverTargetHeight);
+                VDetailLog("{0},MoveLinear,hover,pos={1},dir={2},height={3},target={4}", Prim.LocalID, pos, m_newVelocity, m_VhoverHeight, m_VhoverTargetHeight);
             }
 
             Vector3 posChange = pos - m_lastPositionVector;
@@ -642,9 +654,9 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 }
                 if (changed)
                 {
-                    m_prim.Position = pos;
+                    Prim.Position = pos;
                     VDetailLog("{0},MoveLinear,blockingEndPoint,block={1},origPos={2},pos={3}",
-                                m_prim.LocalID, m_BlockingEndPoint, posChange, pos);
+                                Prim.LocalID, m_BlockingEndPoint, posChange, pos);
                 }
             }
 
@@ -664,7 +676,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 float postemp = (pos.Z - terrainHeight);
                 if (postemp > 2.5f)
                     grav.Z = (float)(grav.Z * 1.037125);
-                VDetailLog("{0},MoveLinear,limitMotorUp,grav={1}", m_prim.LocalID, grav);
+                VDetailLog("{0},MoveLinear,limitMotorUp,grav={1}", Prim.LocalID, grav);
             }
             if ((m_flags & (VehicleFlag.NO_X)) != 0)
                 m_newVelocity.X = 0;
@@ -674,7 +686,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 m_newVelocity.Z = 0;
 
             // Apply velocity
-            m_prim.Velocity = m_newVelocity;
+            Prim.Velocity = m_newVelocity;
             // apply gravity force
             // Why is this set here? The physics engine already does gravity.
             // m_prim.AddForce(grav, false);
@@ -683,11 +695,12 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             Vector3 keepFraction = Vector3.One - (Vector3.One / (m_linearFrictionTimescale / pTimestep));
             m_lastLinearVelocityVector *= keepFraction;
 
-            VDetailLog("{0},MoveLinear,done,lmDir={1},lmVel={2},newVel={3},grav={4},1Mdecay={5}", 
-                    m_prim.LocalID, m_linearMotorDirection, m_lastLinearVelocityVector, m_newVelocity, grav, keepFraction);
+            VDetailLog("{0},MoveLinear,done,lmDir={1},lmVel={2},newVel={3},grav={4},1Mdecay={5}",
+                    Prim.LocalID, m_linearMotorDirection, m_lastLinearVelocityVector, m_newVelocity, grav, keepFraction);
 
         } // end MoveLinear()
 
+        // Apply the effect of the angular motor.
         private void MoveAngular(float pTimestep)
         {
             // m_angularMotorDirection         // angular velocity requested by LSL motor
@@ -699,7 +712,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             // m_lastAngularVelocity           // what was last applied to body
 
             // Get what the body is doing, this includes 'external' influences
-            Vector3 angularVelocity = m_prim.RotationalVelocity;
+            Vector3 angularVelocity = Prim.RotationalVelocity;
 
             if (m_angularMotorApply > 0)
             {
@@ -715,8 +728,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 m_angularMotorVelocity.Y += (m_angularMotorDirection.Y - m_angularMotorVelocity.Y) /  (m_angularMotorTimescale / pTimestep);
                 m_angularMotorVelocity.Z += (m_angularMotorDirection.Z - m_angularMotorVelocity.Z) /  (m_angularMotorTimescale / pTimestep);
 
-                VDetailLog("{0},MoveAngular,angularMotorApply,apply={1},angTScale={2},timeStep={3},origvel={4},dir={5},vel={6}", 
-                        m_prim.LocalID, m_angularMotorApply, m_angularMotorTimescale, pTimestep, origAngularVelocity, m_angularMotorDirection, m_angularMotorVelocity);
+                VDetailLog("{0},MoveAngular,angularMotorApply,apply={1},angTScale={2},timeStep={3},origvel={4},dir={5},vel={6}",
+                        Prim.LocalID, m_angularMotorApply, m_angularMotorTimescale, pTimestep, origAngularVelocity, m_angularMotorDirection, m_angularMotorVelocity);
 
                 // This is done so that if script request rate is less than phys frame rate the expected
                 //    velocity may still be acheived.
@@ -737,7 +750,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             {
                 float VAservo = 0.2f / (m_verticalAttractionTimescale / pTimestep);
                 // get present body rotation
-                Quaternion rotq = m_prim.Orientation;
+                Quaternion rotq = Prim.Orientation;
                 // make a vector pointing up
                 Vector3 verterr = Vector3.Zero;
                 verterr.Z = 1.0f;
@@ -766,8 +779,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 vertattr.X += bounce * angularVelocity.X;
                 vertattr.Y += bounce * angularVelocity.Y;
 
-                VDetailLog("{0},MoveAngular,verticalAttraction,verterr={1},bounce={2},vertattr={3}", 
-                            m_prim.LocalID, verterr, bounce, vertattr);
+                VDetailLog("{0},MoveAngular,verticalAttraction,verterr={1},bounce={2},vertattr={3}",
+                            Prim.LocalID, verterr, bounce, vertattr);
 
             } // else vertical attractor is off
 
@@ -779,18 +792,18 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 
             // Sum velocities
             m_lastAngularVelocity = m_angularMotorVelocity + vertattr; // + bank + deflection
-            
+         
             if ((m_flags & (VehicleFlag.NO_DEFLECTION_UP)) != 0)
             {
                 m_lastAngularVelocity.X = 0;
                 m_lastAngularVelocity.Y = 0;
-                VDetailLog("{0},MoveAngular,noDeflectionUp,lastAngular={1}", m_prim.LocalID, m_lastAngularVelocity);
+                VDetailLog("{0},MoveAngular,noDeflectionUp,lastAngular={1}", Prim.LocalID, m_lastAngularVelocity);
             }
 
             if (m_lastAngularVelocity.ApproxEquals(Vector3.Zero, 0.01f))
             {
                 m_lastAngularVelocity = Vector3.Zero; // Reduce small value to zero.
-                VDetailLog("{0},MoveAngular,zeroSmallValues,lastAngular={1}", m_prim.LocalID, m_lastAngularVelocity);
+                VDetailLog("{0},MoveAngular,zeroSmallValues,lastAngular={1}", Prim.LocalID, m_lastAngularVelocity);
             }
 
              // apply friction
@@ -798,14 +811,14 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             m_lastAngularVelocity -= m_lastAngularVelocity * decayamount;
 
             // Apply to the body
-            m_prim.RotationalVelocity = m_lastAngularVelocity;
+            Prim.RotationalVelocity = m_lastAngularVelocity;
 
-            VDetailLog("{0},MoveAngular,done,decay={1},lastAngular={2}", m_prim.LocalID, decayamount, m_lastAngularVelocity);
+            VDetailLog("{0},MoveAngular,done,decay={1},lastAngular={2}", Prim.LocalID, decayamount, m_lastAngularVelocity);
         } //end MoveAngular
 
         internal void LimitRotation(float timestep)
         {
-            Quaternion rotq = m_prim.Orientation;
+            Quaternion rotq = Prim.Orientation;
             Quaternion m_rot = rotq;
             bool changed = false;
             if (m_RollreferenceFrame != Quaternion.Identity)
@@ -840,8 +853,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             }
             if (changed)
             {
-                m_prim.Orientation = m_rot;
-                VDetailLog("{0},LimitRotation,done,orig={1},new={2}", m_prim.LocalID, rotq, m_rot);
+                Prim.Orientation = m_rot;
+                VDetailLog("{0},LimitRotation,done,orig={1},new={2}", Prim.LocalID, rotq, m_rot);
             }
 
         }
@@ -849,8 +862,8 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         // Invoke the detailed logger and output something if it's enabled.
         private void VDetailLog(string msg, params Object[] args)
         {
-            if (m_prim.Scene.VehicleLoggingEnabled)
-                m_prim.Scene.PhysicsLogging.Write(msg, args);
+            if (Prim.PhysicsScene.VehicleLoggingEnabled)
+                Prim.PhysicsScene.PhysicsLogging.Write(msg, args);
         }
     }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSHingeConstraint.cs b/OpenSim/Region/Physics/BulletSPlugin/BSHingeConstraint.cs
index d68048b..7c8a215 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSHingeConstraint.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSHingeConstraint.cs
@@ -1,55 +1,57 @@
-/*

- * 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 OpenMetaverse;

-

-namespace OpenSim.Region.Physics.BulletSPlugin

-{

-

-class BSHingeConstraint : BSConstraint

-{

-    public BSHingeConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,

-                    Vector3 pivotInA, Vector3 pivotInB,

-                    Vector3 axisInA, Vector3 axisInB,

-                    bool useLinearReferenceFrameA, bool disableCollisionsBetweenLinkedBodies)

-    {

-        m_world = world;

-        m_body1 = obj1;

-        m_body2 = obj2;

-        m_constraint = new BulletConstraint(

-                            BulletSimAPI.CreateHingeConstraint2(m_world.Ptr, m_body1.Ptr, m_body2.Ptr,

-                                pivotInA, pivotInB,

-                                axisInA, axisInB,

-                                useLinearReferenceFrameA, disableCollisionsBetweenLinkedBodies));

-        m_enabled = true;

-    }

-

-}

-

-}

+/*
+ * 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 OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+
+class BSHingeConstraint : BSConstraint
+{
+    public override ConstraintType Type { get { return ConstraintType.HINGE_CONSTRAINT_TYPE; } }
+
+    public BSHingeConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,
+                    Vector3 pivotInA, Vector3 pivotInB,
+                    Vector3 axisInA, Vector3 axisInB,
+                    bool useLinearReferenceFrameA, bool disableCollisionsBetweenLinkedBodies)
+    {
+        m_world = world;
+        m_body1 = obj1;
+        m_body2 = obj2;
+        m_constraint = new BulletConstraint(
+                            BulletSimAPI.CreateHingeConstraint2(m_world.ptr, m_body1.ptr, m_body2.ptr,
+                                pivotInA, pivotInB,
+                                axisInA, axisInB,
+                                useLinearReferenceFrameA, disableCollisionsBetweenLinkedBodies));
+        m_enabled = true;
+    }
+
+}
+
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
index 7e784eb..4f225ae 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
@@ -36,17 +36,24 @@ public class BSLinkset
 {
     private static string LogHeader = "[BULLETSIM LINKSET]";
 
-    private BSPhysObject m_linksetRoot;
-    public BSPhysObject LinksetRoot { get { return m_linksetRoot; } }
+    public BSPhysObject LinksetRoot { get; protected set; }
 
-    private BSScene m_physicsScene;
-    public BSScene PhysicsScene { get { return m_physicsScene; } }
+    public BSScene PhysicsScene { get; private set; }
 
     static int m_nextLinksetID = 1;
     public int LinksetID { get; private set; }
 
-    // The children under the root in this linkset
+    // The children under the root in this linkset.
+    // There are two lists of children: the current children at runtime
+    //    and the children at taint-time. For instance, if you delink a
+    //    child from the linkset, the child is removed from m_children
+    //    but the constraint won't be removed until taint time.
+    //    Two lists lets this track the 'current' children and
+    //    the physical 'taint' children separately.
+    // After taint processing and before the simulation step, these
+    //    two lists must be the same.
     private List<BSPhysObject> m_children;
+    private List<BSPhysObject> m_taintChildren;
 
     // We lock the diddling of linkset classes to prevent any badness.
     // This locks the modification of the instances of this class. Changes
@@ -55,9 +62,9 @@ public class BSLinkset
 
     // We keep the prim's mass in the linkset structure since it could be dependent on other prims
     private float m_mass;
-    public float LinksetMass 
-    { 
-        get 
+    public float LinksetMass
+    {
+        get
         {
             m_mass = ComputeLinksetMass();
             return m_mass;
@@ -79,22 +86,26 @@ public class BSLinkset
         // A simple linkset of one (no children)
         LinksetID = m_nextLinksetID++;
         // We create LOTS of linksets.
-        if (m_nextLinksetID < 0) 
+        if (m_nextLinksetID <= 0)
             m_nextLinksetID = 1;
-        m_physicsScene = scene;
-        m_linksetRoot = parent;
+        PhysicsScene = scene;
+        LinksetRoot = parent;
         m_children = new List<BSPhysObject>();
+        m_taintChildren = new List<BSPhysObject>();
         m_mass = parent.MassRaw;
     }
 
     // Link to a linkset where the child knows the parent.
     // Parent changing should not happen so do some sanity checking.
     // We return the parent's linkset so the child can track its membership.
+    // Called at runtime.
     public BSLinkset AddMeToLinkset(BSPhysObject child)
     {
         lock (m_linksetActivityLock)
         {
-            AddChildToLinkset(child);
+            // Don't add the root to its own linkset
+            if (!IsRoot(child))
+                AddChildToLinkset(child);
         }
         return this;
     }
@@ -102,26 +113,18 @@ public class BSLinkset
     // Remove a child from a linkset.
     // Returns a new linkset for the child which is a linkset of one (just the
     //    orphened child).
+    // Called at runtime.
     public BSLinkset RemoveMeFromLinkset(BSPhysObject child)
     {
         lock (m_linksetActivityLock)
         {
             if (IsRoot(child))
             {
-                // if root of linkset, take the linkset apart
-                while (m_children.Count > 0)
-                {
-                    // Note that we don't do a foreach because the remove routine
-                    //    takes it out of the list.
-                    RemoveChildFromOtherLinkset(m_children[0]);
-                }
-                m_children.Clear(); // just to make sure
-            }
-            else
-            {
-                // Just removing a child from an existing linkset
-                RemoveChildFromLinkset(child);
+                // Cannot remove the root from a linkset.
+                return this;
             }
+
+            RemoveChildFromLinkset(child);
         }
 
         // The child is down to a linkset of just itself
@@ -131,7 +134,7 @@ public class BSLinkset
     // Return 'true' if the passed object is the root object of this linkset
     public bool IsRoot(BSPhysObject requestor)
     {
-        return (requestor.LocalID == m_linksetRoot.LocalID);
+        return (requestor.LocalID == LinksetRoot.LocalID);
     }
 
     public int NumberOfChildren { get { return m_children.Count; } }
@@ -157,51 +160,6 @@ public class BSLinkset
         return ret;
     }
 
-    private float ComputeLinksetMass()
-    {
-        float mass = m_linksetRoot.MassRaw;
-        foreach (BSPhysObject bp in m_children)
-        {
-            mass += bp.MassRaw;
-        }
-        return mass;
-    }
-
-    private OMV.Vector3 ComputeLinksetCenterOfMass()
-    {
-        OMV.Vector3 com = m_linksetRoot.Position * m_linksetRoot.MassRaw;
-        float totalMass = m_linksetRoot.MassRaw;
-
-        lock (m_linksetActivityLock)
-        {
-            foreach (BSPhysObject bp in m_children)
-            {
-                com += bp.Position * bp.MassRaw;
-                totalMass += bp.MassRaw;
-            }
-            if (totalMass != 0f)
-                com /= totalMass;
-        }
-
-        return com;
-    }
-
-    private OMV.Vector3 ComputeLinksetGeometricCenter()
-    {
-        OMV.Vector3 com = m_linksetRoot.Position;
-
-        lock (m_linksetActivityLock)
-        {
-            foreach (BSPhysObject bp in m_children)
-            {
-                com += bp.Position * bp.MassRaw;
-            }
-            com /= (m_children.Count + 1);
-        }
-
-        return com;
-    }
-
     // The object is going dynamic (physical). Do any setup necessary
     //     for a dynamic linkset.
     // Only the state of the passed object can be modified. The rest of the linkset
@@ -210,8 +168,8 @@ public class BSLinkset
     // Called at taint-time!
     public bool MakeDynamic(BSPhysObject child)
     {
-        bool ret = false;
-        return ret;
+        // What is done for each object in BSPrim is what we want.
+        return false;
     }
 
     // The object is going static (non-physical). Do any setup necessary
@@ -226,6 +184,7 @@ public class BSLinkset
 
     // When physical properties are changed the linkset needs to recalculate
     //   its internal properties.
+    // Called at runtime.
     public void Refresh(BSPhysObject requestor)
     {
         // If there are no children, there can't be any constraints to recompute
@@ -242,58 +201,125 @@ public class BSLinkset
         }
     }
 
-    // Call each of the constraints that make up this linkset and recompute the
-    //    various transforms and variables. Used when objects are added or removed
-    //    from a linkset to make sure the constraints know about the new mass and
-    //    geometry.
-    // Must only be called at taint time!!
-    private void RecomputeLinksetConstraintVariables()
+    // Routine used when rebuilding the body of the root of the linkset
+    // Destroy all the constraints have have been made to root.
+    // This is called when the root body is changing.
+    // Returns 'true' of something eas actually removed and would need restoring
+    // Called at taint-time!!
+    public bool RemoveBodyDependencies(BSPrim child)
     {
-        float linksetMass = LinksetMass;
+        bool ret = false;
+
         lock (m_linksetActivityLock)
         {
-            bool somethingMissing = false;
-            foreach (BSPhysObject child in m_children)
+            if (IsRoot(child))
             {
-                BSConstraint constrain;
-                if (m_physicsScene.Constraints.TryGetConstraint(LinksetRoot.BSBody, child.BSBody, out constrain))
+                // If the one with the dependency is root, must undo all children
+                DetailLog("{0},BSLinkset.RemoveBodyDependencies,removeChildrenForRoot,rID={1},numChild={2}",
+                                                child.LocalID, LinksetRoot.LocalID, m_taintChildren.Count);
+                foreach (BSPhysObject bpo in m_taintChildren)
                 {
-                    // DetailLog("{0},BSLinkset.RecomputeLinksetConstraintVariables,taint,child={1},mass={2},A={3},B={4}", 
-                    //         LinksetRoot.LocalID, child.LocalID, linksetMass, constrain.Body1.ID, constrain.Body2.ID);
-                    constrain.RecomputeConstraintVariables(linksetMass);
+                    PhysicallyUnlinkAChildFromRoot(LinksetRoot, LinksetRoot.BSBody, bpo, bpo.BSBody);
+                    ret = true;
                 }
-                else
+            }
+            else
+            {
+                DetailLog("{0},BSLinkset.RemoveBodyDependencies,removeSingleChild,rID={1},rBody={2},cID={3},cBody={4}",
+                                                child.LocalID,
+                                                LinksetRoot.LocalID, LinksetRoot.BSBody.ptr.ToString("X"),
+                                                child.LocalID, child.BSBody.ptr.ToString("X"));
+                // Remove the dependency on the body of this one 
+                if (m_taintChildren.Contains(child))
                 {
-                    // Non-fatal error that happens when children are being added to the linkset but
-                    //    their constraints have not been created yet.
-                    // Caused by the fact that m_children is built at run time but building constraints
-                    //    happens at taint time.
-                    somethingMissing = true;
-                    break;
+                    PhysicallyUnlinkAChildFromRoot(LinksetRoot, LinksetRoot.BSBody, child, child.BSBody);
+                    ret = true;
                 }
             }
+        }
+        return ret;
+    }
 
-            // If the whole linkset is not here, doesn't make sense to recompute linkset wide values
-            if (!somethingMissing)
+    // Routine used when rebuilding the body of the root of the linkset
+    // This is called after RemoveAllLinksToRoot() to restore all the constraints.
+    // This is called when the root body has been changed.
+    // Called at taint-time!!
+    public void RestoreBodyDependencies(BSPrim child)
+    {
+        lock (m_linksetActivityLock)
+        {
+            if (IsRoot(child))
             {
-                // If this is a multiple object linkset, set everybody's center of mass to the set's center of mass
-                OMV.Vector3 centerOfMass = ComputeLinksetCenterOfMass();
-                BulletSimAPI.SetCenterOfMassByPosRot2(LinksetRoot.BSBody.Ptr, centerOfMass, OMV.Quaternion.Identity);
-                foreach (BSPhysObject child in m_children)
+                DetailLog("{0},BSLinkset.RestoreBodyDependencies,restoreChildrenForRoot,rID={1},numChild={2}",
+                                                child.LocalID, LinksetRoot.LocalID, m_taintChildren.Count);
+                foreach (BSPhysObject bpo in m_taintChildren)
                 {
-                    BulletSimAPI.SetCenterOfMassByPosRot2(child.BSBody.Ptr, centerOfMass, OMV.Quaternion.Identity);
+                    PhysicallyLinkAChildToRoot(LinksetRoot, LinksetRoot.BSBody, bpo, bpo.BSBody);
                 }
-                /*
-                // The root prim takes on the weight of the whole linkset
-                OMV.Vector3 inertia = BulletSimAPI.CalculateLocalInertia2(LinksetRoot.BSShape.Ptr, linksetMass);
-                BulletSimAPI.SetMassProps2(LinksetRoot.BSBody.Ptr, linksetMass, inertia);
-                OMV.Vector3 centerOfMass = ComputeLinksetCenterOfMass();
-                BulletSimAPI.SetCenterOfMassByPosRot2(LinksetRoot.BSBody.Ptr, centerOfMass, OMV.Quaternion.Identity);
-                BulletSimAPI.UpdateInertiaTensor2(LinksetRoot.BSBody.Ptr);
-                 */
+            }
+            else
+            {
+                DetailLog("{0},BSLinkset.RestoreBodyDependencies,restoreSingleChild,rID={1},rBody={2},cID={3},cBody={4}",
+                                                LinksetRoot.LocalID,
+                                                LinksetRoot.LocalID, LinksetRoot.BSBody.ptr.ToString("X"),
+                                                child.LocalID, child.BSBody.ptr.ToString("X"));
+                PhysicallyLinkAChildToRoot(LinksetRoot, LinksetRoot.BSBody, child, child.BSBody);
             }
         }
-        return;
+    }
+
+    // ================================================================
+    // Below this point is internal magic
+
+    private float ComputeLinksetMass()
+    {
+        float mass;
+        lock (m_linksetActivityLock)
+        {
+            mass = LinksetRoot.MassRaw;
+            foreach (BSPhysObject bp in m_taintChildren)
+            {
+                mass += bp.MassRaw;
+            }
+        }
+        return mass;
+    }
+
+    private OMV.Vector3 ComputeLinksetCenterOfMass()
+    {
+        OMV.Vector3 com;
+        lock (m_linksetActivityLock)
+        {
+            com = LinksetRoot.Position * LinksetRoot.MassRaw;
+            float totalMass = LinksetRoot.MassRaw;
+
+            foreach (BSPhysObject bp in m_taintChildren)
+            {
+                com += bp.Position * bp.MassRaw;
+                totalMass += bp.MassRaw;
+            }
+            if (totalMass != 0f)
+                com /= totalMass;
+        }
+
+        return com;
+    }
+
+    private OMV.Vector3 ComputeLinksetGeometricCenter()
+    {
+        OMV.Vector3 com;
+        lock (m_linksetActivityLock)
+        {
+            com = LinksetRoot.Position;
+
+            foreach (BSPhysObject bp in m_taintChildren)
+            {
+                com += bp.Position * bp.MassRaw;
+            }
+            com /= (m_taintChildren.Count + 1);
+        }
+
+        return com;
     }
 
     // I am the root of a linkset and a new child is being added
@@ -304,12 +330,22 @@ public class BSLinkset
         {
             m_children.Add(child);
 
-            BSPhysObject rootx = LinksetRoot; // capture the root as of now
+            BSPhysObject rootx = LinksetRoot; // capture the root and body as of now
+            BulletBody rootBodyx = LinksetRoot.BSBody;
             BSPhysObject childx = child;
-            m_physicsScene.TaintedObject("AddChildToLinkset", delegate()
+            BulletBody childBodyx = child.BSBody;
+
+            DetailLog("{0},AddChildToLinkset,call,rID={1},rBody={2},cID={3},cBody={4}", 
+                            rootx.LocalID,
+                            rootx.LocalID, rootBodyx.ptr.ToString("X"),
+                            childx.LocalID, childBodyx.ptr.ToString("X"));
+
+            PhysicsScene.TaintedObject("AddChildToLinkset", delegate()
             {
-                DetailLog("{0},AddChildToLinkset,taint,child={1}", m_linksetRoot.LocalID, child.LocalID);
-                PhysicallyLinkAChildToRoot(rootx, childx);     // build the physical binding between me and the child
+                DetailLog("{0},AddChildToLinkset,taint,child={1}", LinksetRoot.LocalID, child.LocalID);
+                // build the physical binding between me and the child
+                m_taintChildren.Add(childx);
+                PhysicallyLinkAChildToRoot(rootx, rootBodyx, childx, childBodyx);
             });
         }
         return;
@@ -319,10 +355,10 @@ public class BSLinkset
     // This is not being called by the child so we have to make sure the child doesn't think
     //    it's still connected to the linkset.
     // Normal OpenSimulator operation will never do this because other SceneObjectPart information
-    //    has to be updated also (like pointer to prim's parent).
+    //    also has to be updated (like pointer to prim's parent).
     private void RemoveChildFromOtherLinkset(BSPhysObject pchild)
     {
-        pchild.Linkset = new BSLinkset(m_physicsScene, pchild);
+        pchild.Linkset = new BSLinkset(PhysicsScene, pchild);
         RemoveChildFromLinkset(pchild);
     }
 
@@ -332,13 +368,22 @@ public class BSLinkset
     {
         if (m_children.Remove(child))
         {
-            BSPhysObject rootx = LinksetRoot; // capture the root as of now
+            BSPhysObject rootx = LinksetRoot; // capture the root and body as of now
+            BulletBody rootBodyx = LinksetRoot.BSBody;
             BSPhysObject childx = child;
-            m_physicsScene.TaintedObject("RemoveChildFromLinkset", delegate()
+            BulletBody childBodyx = child.BSBody;
+
+            DetailLog("{0},RemoveChildFromLinkset,call,rID={1},rBody={2},cID={3},cBody={4}", 
+                            childx.LocalID,
+                            rootx.LocalID, rootBodyx.ptr.ToString("X"),
+                            childx.LocalID, childBodyx.ptr.ToString("X"));
+
+            PhysicsScene.TaintedObject("RemoveChildFromLinkset", delegate()
             {
-                DetailLog("{0},RemoveChildFromLinkset,taint,child={1}", m_linksetRoot.LocalID, child.LocalID);
+                if (m_taintChildren.Contains(childx))
+                    m_taintChildren.Remove(childx);
 
-                PhysicallyUnlinkAChildFromRoot(rootx, childx);
+                PhysicallyUnlinkAChildFromRoot(rootx, rootBodyx, childx, childBodyx);
                 RecomputeLinksetConstraintVariables();
             });
 
@@ -353,7 +398,8 @@ public class BSLinkset
 
     // Create a constraint between me (root of linkset) and the passed prim (the child).
     // Called at taint time!
-    private void PhysicallyLinkAChildToRoot(BSPhysObject rootPrim, BSPhysObject childPrim)
+    private void PhysicallyLinkAChildToRoot(BSPhysObject rootPrim, BulletBody rootBody,
+                                    BSPhysObject childPrim, BulletBody childBody)
     {
         // Zero motion for children so they don't interpolate
         childPrim.ZeroMotion();
@@ -365,18 +411,36 @@ public class BSLinkset
         // real world coordinate of midpoint between the two objects
         OMV.Vector3 midPoint = rootPrim.Position + (childRelativePosition / 2);
 
+        DetailLog("{0},PhysicallyLinkAChildToRoot,taint,root={1},rBody={2},child={3},cBody={4},rLoc={5},cLoc={6},midLoc={7}",
+                                        rootPrim.LocalID,
+                                        rootPrim.LocalID, rootBody.ptr.ToString("X"),
+                                        childPrim.LocalID, childBody.ptr.ToString("X"),
+                                        rootPrim.Position, childPrim.Position, midPoint);
+
         // create a constraint that allows no freedom of movement between the two objects
         // http://bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=4818
-        DetailLog("{0},PhysicallyLinkAChildToRoot,taint,root={1},child={2},rLoc={3},cLoc={4},midLoc={5}", 
-            rootPrim.LocalID, rootPrim.LocalID, childPrim.LocalID, rootPrim.Position, childPrim.Position, midPoint);
+
+        // There is great subtlty in these paramters. Notice the check for a ptr of zero.
+        // We pass the BulletBody structure into the taint in order to capture the pointer
+        //     of the body at the time of constraint creation. This doesn't work for the very first
+        //     construction because there is no body yet. The body
+        //     is constructed later at taint time. Thus we use the body address at time of the
+        //     taint creation but, if it is zero, use what's in the prim at the moment.
+        //     There is a possible race condition since shape can change without a taint call
+        //     (like changing to a mesh that is already constructed). The fix for that would be
+        //     to only change BSShape at taint time thus syncronizing these operations at
+        //     the cost of efficiency and lag.
         BS6DofConstraint constrain = new BS6DofConstraint(
-                        m_physicsScene.World, rootPrim.BSBody, childPrim.BSBody,
+                        PhysicsScene.World,
+                        rootBody.ptr == IntPtr.Zero ? rootPrim.BSBody : rootBody,
+                        childBody.ptr == IntPtr.Zero ? childPrim.BSBody : childBody,
                         midPoint,
                         true,
                         true
                         );
+
         /* NOTE: below is an attempt to build constraint with full frame computation, etc.
-         *     Using the midpoint is easier since it lets the Bullet code use the transforms
+         *     Using the midpoint is easier since it lets the Bullet code manipulate the transforms
          *     of the objects.
          * Code left as a warning to future programmers.
         // ==================================================================================
@@ -408,7 +472,7 @@ public class BSLinkset
         // ==================================================================================
         */
 
-        m_physicsScene.Constraints.AddConstraint(constrain);
+        PhysicsScene.Constraints.AddConstraint(constrain);
 
         // zero linear and angular limits makes the objects unable to move in relation to each other
         constrain.SetLinearLimits(OMV.Vector3.Zero, OMV.Vector3.Zero);
@@ -429,31 +493,79 @@ public class BSLinkset
     }
 
     // Remove linkage between myself and a particular child
+    // The root and child bodies are passed in because we need to remove the constraint between
+    //      the bodies that were at unlink time.
     // Called at taint time!
-    private void PhysicallyUnlinkAChildFromRoot(BSPhysObject rootPrim, BSPhysObject childPrim)
+    private void PhysicallyUnlinkAChildFromRoot(BSPhysObject rootPrim, BulletBody rootBody,
+                                                    BSPhysObject childPrim, BulletBody childBody)
     {
-        DetailLog("{0},PhysicallyUnlinkAChildFromRoot,taint,root={1},child={2}", rootPrim.LocalID, rootPrim.LocalID, childPrim.LocalID);
+        DetailLog("{0},PhysicallyUnlinkAChildFromRoot,taint,root={1},rBody={2},child={3},cBody={4}",
+                            rootPrim.LocalID,
+                            rootPrim.LocalID, rootBody.ptr.ToString("X"),
+                            childPrim.LocalID, childBody.ptr.ToString("X"));
 
         // Find the constraint for this link and get rid of it from the overall collection and from my list
-        m_physicsScene.Constraints.RemoveAndDestroyConstraint(rootPrim.BSBody, childPrim.BSBody);
+        PhysicsScene.Constraints.RemoveAndDestroyConstraint(rootBody, childBody);
 
         // Make the child refresh its location
-        BulletSimAPI.PushUpdate2(childPrim.BSBody.Ptr);
+        BulletSimAPI.PushUpdate2(childPrim.BSBody.ptr);
     }
 
-    // Remove linkage between myself and any possible children I might have
+    /*
+    // Remove linkage between myself and any possible children I might have.
     // Called at taint time!
     private void PhysicallyUnlinkAllChildrenFromRoot(BSPhysObject rootPrim)
     {
         DetailLog("{0},PhysicallyUnlinkAllChildren,taint", rootPrim.LocalID);
 
-        m_physicsScene.Constraints.RemoveAndDestroyConstraint(rootPrim.BSBody);
+        PhysicsScene.Constraints.RemoveAndDestroyConstraint(rootPrim.BSBody);
+    }
+     */
+
+    // Call each of the constraints that make up this linkset and recompute the
+    //    various transforms and variables. Used when objects are added or removed
+    //    from a linkset to make sure the constraints know about the new mass and
+    //    geometry.
+    // Must only be called at taint time!!
+    private void RecomputeLinksetConstraintVariables()
+    {
+        float linksetMass = LinksetMass;
+        foreach (BSPhysObject child in m_taintChildren)
+        {
+            BSConstraint constrain;
+            if (PhysicsScene.Constraints.TryGetConstraint(LinksetRoot.BSBody, child.BSBody, out constrain))
+            {
+                // DetailLog("{0},BSLinkset.RecomputeLinksetConstraintVariables,taint,child={1},mass={2},A={3},B={4}",
+                //         LinksetRoot.LocalID, child.LocalID, linksetMass, constrain.Body1.ID, constrain.Body2.ID);
+                constrain.RecomputeConstraintVariables(linksetMass);
+            }
+            else
+            {
+                // Non-fatal error that happens when children are being added to the linkset but
+                //    their constraints have not been created yet.
+                break;
+            }
+        }
+
+        // If the whole linkset is not here, doesn't make sense to recompute linkset wide values
+        if (m_children.Count == m_taintChildren.Count)
+        {
+            // If this is a multiple object linkset, set everybody's center of mass to the set's center of mass
+            OMV.Vector3 centerOfMass = ComputeLinksetCenterOfMass();
+            BulletSimAPI.SetCenterOfMassByPosRot2(LinksetRoot.BSBody.ptr, centerOfMass, OMV.Quaternion.Identity);
+            foreach (BSPhysObject child in m_taintChildren)
+            {
+                BulletSimAPI.SetCenterOfMassByPosRot2(child.BSBody.ptr, centerOfMass, OMV.Quaternion.Identity);
+            }
+        }
+        return;
     }
 
+
     // Invoke the detailed logger and output something if it's enabled.
     private void DetailLog(string msg, params Object[] args)
     {
-        m_physicsScene.PhysicsLogging.Write(msg, args);
+        PhysicsScene.PhysicsLogging.Write(msg, args);
     }
 
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
index 3fe71e1..d9b738b 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
@@ -1,4 +1,4 @@
-/*
+/*
  * Copyright (c) Contributors, http://opensimulator.org/
  * See CONTRIBUTORS.TXT for a full list of copyright holders.
  *
@@ -39,26 +39,171 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 // unless the difference is significant.
 public abstract class BSPhysObject : PhysicsActor
 {
-    public abstract BSLinkset Linkset { get; set; }
+    protected void BaseInitialize(BSScene parentScene, uint localID, string name, string typeName)
+    {
+        PhysicsScene = parentScene;
+        LocalID = localID;
+        PhysObjectName = name;
+        TypeName = typeName;
 
-    public abstract bool Collide(uint collidingWith, BSPhysObject collidee,
-            OMV.Vector3 contactPoint, OMV.Vector3 contactNormal, float pentrationDepth);
-    public abstract void SendCollisions();
+        Linkset = new BSLinkset(PhysicsScene, this);
 
-    // Return the object mass without calculating it or side effects
+        CollisionCollection = new CollisionEventUpdate();
+        SubscribedEventsMs = 0;
+        CollidingStep = 0;
+        CollidingGroundStep = 0;
+    }
+
+    public BSScene PhysicsScene { get; protected set; }
+    // public override uint LocalID { get; set; } // Use the LocalID definition in PhysicsActor
+    public string PhysObjectName { get; protected set; }
+    public string TypeName { get; protected set; }
+
+    public BSLinkset Linkset { get; set; }
+
+    // Return the object mass without calculating it or having side effects
     public abstract float MassRaw { get; }
 
     // Reference to the physical body (btCollisionObject) of this object
-    public abstract BulletBody BSBody { get; set; }
+    public BulletBody BSBody;
     // Reference to the physical shape (btCollisionShape) of this object
-    public abstract BulletShape BSShape { get; set; }
+    public BulletShape BSShape;
 
+    // Stop all physical motion.
     public abstract void ZeroMotion();
 
+    // Step the vehicle simulation for this object. A NOOP if the vehicle was not configured.
     public virtual void StepVehicle(float timeStep) { }
 
+    // Update the physical location and motion of the object. Called with data from Bullet.
     public abstract void UpdateProperties(EntityProperties entprop);
 
+    // Tell the object to clean up.
     public abstract void Destroy();
+
+    #region Collisions
+
+    // Requested number of milliseconds between collision events. Zero means disabled.
+    protected int SubscribedEventsMs { get; set; }
+    // Given subscription, the time that a collision may be passed up
+    protected int NextCollisionOkTime { get; set; }
+    // The simulation step that last had a collision
+    protected long CollidingStep { get; set; }
+    // The simulation step that last had a collision with the ground
+    protected long CollidingGroundStep { get; set; }
+    // The collision flags we think are set in Bullet
+    protected CollisionFlags CurrentCollisionFlags { get; set; }
+
+    // The collisions that have been collected this tick
+    protected CollisionEventUpdate CollisionCollection;
+
+    // The simulation step is telling this object about a collision.
+    // Return 'true' if a collision was processed and should be sent up.
+    // Called at taint time from within the Step() function
+    public virtual bool Collide(uint collidingWith, BSPhysObject collidee,
+                    OMV.Vector3 contactPoint, OMV.Vector3 contactNormal, float pentrationDepth)
+    {
+        bool ret = false;
+
+        // The following lines make IsColliding() and IsCollidingGround() work
+        CollidingStep = PhysicsScene.SimulationStep;
+        if (collidingWith <= PhysicsScene.TerrainManager.HighestTerrainID)
+        {
+            CollidingGroundStep = PhysicsScene.SimulationStep;
+        }
+
+        // prims in the same linkset cannot collide with each other
+        if (collidee != null && (this.Linkset.LinksetID == collidee.Linkset.LinksetID))
+        {
+            return ret;
+        }
+
+        // if someone has subscribed for collision events....
+        if (SubscribedEvents()) {
+            CollisionCollection.AddCollider(collidingWith, new ContactPoint(contactPoint, contactNormal, pentrationDepth));
+            // DetailLog("{0},{1}.Collison.AddCollider,call,with={2},point={3},normal={4},depth={5}",
+            //                 LocalID, TypeName, collidingWith, contactPoint, contactNormal, pentrationDepth);
+
+            ret = true;
+        }
+        return ret;
+    }
+
+    // Routine to send the collected collisions into the simulator.
+    // Also handles removal of this from the collection of objects with collisions if
+    //      there are no collisions from this object. Mechanism is create one last
+    //      collision event to make collision_end work.
+    // Called at taint time from within the Step() function thus no locking problems
+    //      with CollisionCollection and ObjectsWithNoMoreCollisions.
+    // Return 'true' if there were some actual collisions passed up
+    public virtual bool SendCollisions()
+    {
+        bool ret = true;
+
+        // throttle the collisions to the number of milliseconds specified in the subscription
+        int nowTime = PhysicsScene.SimulationNowTime;
+        if (nowTime >= NextCollisionOkTime)
+        {
+            NextCollisionOkTime = nowTime + SubscribedEventsMs;
+
+            // We are called if we previously had collisions. If there are no collisions
+            //   this time, send up one last empty event so OpenSim can sense collision end.
+            if (CollisionCollection.Count == 0)
+            {
+                // If I have no collisions this time, remove me from the list of objects with collisions.
+                ret = false;
+            }
+
+            // DetailLog("{0},{1}.SendCollisionUpdate,call,numCollisions={2}", LocalID, TypeName, CollisionCollection.Count);
+            base.SendCollisionUpdate(CollisionCollection);
+
+            // The collisionCollection structure is passed around in the simulator.
+            // Make sure we don't have a handle to that one and that a new one is used for next time.
+            CollisionCollection = new CollisionEventUpdate();
+        }
+        return ret;
+    }
+
+    // Subscribe for collision events.
+    // Parameter is the millisecond rate the caller wishes collision events to occur.
+    public override void SubscribeEvents(int ms) {
+        // DetailLog("{0},{1}.SubscribeEvents,subscribing,ms={2}", LocalID, TypeName, ms);
+        SubscribedEventsMs = ms;
+        if (ms > 0)
+        {
+            // make sure first collision happens
+            NextCollisionOkTime = Util.EnvironmentTickCountSubtract(SubscribedEventsMs);
+
+            PhysicsScene.TaintedObject(TypeName+".SubscribeEvents", delegate()
+            {
+                CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+            });
+        }
+        else
+        {
+            // Subscribing for zero or less is the same as unsubscribing
+            UnSubscribeEvents();
+        }
+    }
+    public override void UnSubscribeEvents() { 
+        // DetailLog("{0},{1}.UnSubscribeEvents,unsubscribing", LocalID, TypeName);
+        SubscribedEventsMs = 0;
+        PhysicsScene.TaintedObject(TypeName+".UnSubscribeEvents", delegate()
+        {
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+        });
+    }
+    // Return 'true' if the simulator wants collision events
+    public override bool SubscribedEvents() { 
+        return (SubscribedEventsMs > 0);
+    }
+
+    #endregion // Collisions
+
+    // High performance detailed logging routine used by the physical objects.
+    protected void DetailLog(string msg, params Object[] args)
+    {
+        PhysicsScene.PhysicsLogging.Write(msg, args);
+    }
 }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPlugin.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPlugin.cs
index 0f027b8..20f5180 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPlugin.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPlugin.cs
@@ -33,7 +33,7 @@ using OpenMetaverse;
 namespace OpenSim.Region.Physics.BulletSPlugin
 {
     /// <summary>
-    /// Entry for a port of Bullet (http://bulletphysics.org/) to OpenSim. 
+    /// Entry for a port of Bullet (http://bulletphysics.org/) to OpenSim.
     /// This module interfaces to an unmanaged C++ library which makes the
     /// actual calls into the Bullet physics engine.
     /// The unmanaged library is found in opensim-libs::trunk/unmanaged/BulletSim/.
@@ -62,7 +62,7 @@ public class BSPlugin : IPhysicsPlugin
             if (Util.IsWindows())
                 Util.LoadArchSpecificWindowsDll("BulletSim.dll");
             // If not Windows, loading is performed by the
-            // Mono loader as specified in 
+            // Mono loader as specified in
             // "bin/Physics/OpenSim.Region.Physics.BulletSPlugin.dll.config".
 
             _mScene = new BSScene(sceneIdentifier);
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 26a581f..a0e627e 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -24,6 +24,9 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
+
+// Uncomment this it enable code to do all shape an body memory management
+//    in the C# code.
 using System;
 using System.Reflection;
 using System.Collections.Generic;
@@ -36,6 +39,7 @@ using OpenSim.Region.Physics.ConvexDecompositionDotNet;
 
 namespace OpenSim.Region.Physics.BulletSPlugin
 {
+
     [Serializable]
 public sealed class BSPrim : BSPhysObject
 {
@@ -49,11 +53,6 @@ public sealed class BSPrim : BSPhysObject
     private ulong _hullKey;
     private List<ConvexResult> _hulls;
 
-    private BSScene _scene;
-    public BSScene Scene { get { return _scene; } }
-    private String _avName;
-    private uint _localID = 0;
-
     // _size is what the user passed. _scale is what we pass to the physics engine with the mesh.
     // Often _scale is unity because the meshmerizer will apply _size when creating the mesh.
     private OMV.Vector3 _size;  // the multiplier for each mesh dimension as passed by the user
@@ -87,18 +86,6 @@ public sealed class BSPrim : BSPhysObject
     private bool _kinematic;
     private float _buoyancy;
 
-    // Membership in a linkset is controlled by this class.
-    public override BSLinkset Linkset { get; set; }
-
-    private int _subscribedEventsMs = 0;
-    private int _nextCollisionOkTime = 0;
-    long _collidingStep;
-    long _collidingGroundStep;
-    CollisionFlags m_currentCollisionFlags = 0;
-
-    public override BulletBody BSBody { get; set; }
-    public override BulletShape BSShape { get; set; }
-
     private BSDynamics _vehicle;
 
     private OMV.Vector3 _PIDTarget;
@@ -113,10 +100,8 @@ public sealed class BSPrim : BSPhysObject
                        OMV.Quaternion rotation, PrimitiveBaseShape pbs, bool pisPhysical)
     {
         // m_log.DebugFormat("{0}: BSPrim creation of {1}, id={2}", LogHeader, primName, localID);
-        _localID = localID;
-        _avName = primName;
+        base.BaseInitialize(parent_scene, localID, primName, "BSPrim");
         _physicsActorType = (int)ActorTypes.Prim;
-        _scene = parent_scene;
         _position = pos;
         _size = size;
         _scale = new OMV.Vector3(1f, 1f, 1f);   // the scale will be set by CreateGeom depending on object type
@@ -129,25 +114,23 @@ public sealed class BSPrim : BSPhysObject
         _pbs = pbs;
         _isPhysical = pisPhysical;
         _isVolumeDetect = false;
-        _subscribedEventsMs = 0;
-        _friction = _scene.Params.defaultFriction;  // TODO: compute based on object material
-        _density = _scene.Params.defaultDensity;    // TODO: compute based on object material
-        _restitution = _scene.Params.defaultRestitution;
-        Linkset = new BSLinkset(Scene, this);     // a linkset of one
-        _vehicle = new BSDynamics(Scene, this);            // add vehicleness
+        _friction = PhysicsScene.Params.defaultFriction;  // TODO: compute based on object material
+        _density = PhysicsScene.Params.defaultDensity;    // TODO: compute based on object material
+        _restitution = PhysicsScene.Params.defaultRestitution;
+        _vehicle = new BSDynamics(PhysicsScene, this);            // add vehicleness
         _mass = CalculateMass();
+
+        // No body or shape yet
+        BSBody = new BulletBody(LocalID, IntPtr.Zero);
+        BSShape = new BulletShape(IntPtr.Zero);
+
         DetailLog("{0},BSPrim.constructor,call", LocalID);
         // do the actual object creation at taint time
-        _scene.TaintedObject("BSPrim.create", delegate()
+        PhysicsScene.TaintedObject("BSPrim.create", delegate()
         {
             CreateGeomAndObject(true);
 
-            // Get the pointer to the physical body for this object.
-            // At the moment, we're still letting BulletSim manage the creation and destruction
-            //    of the object. Someday we'll move that into the C# code.
-            BSBody = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(_scene.World.Ptr, LocalID));
-            BSShape = new BulletShape(BulletSimAPI.GetCollisionShape2(BSBody.Ptr));
-            m_currentCollisionFlags = BulletSimAPI.GetCollisionFlags2(BSBody.Ptr);
+            CurrentCollisionFlags = BulletSimAPI.GetCollisionFlags2(BSBody.ptr);
         });
     }
 
@@ -168,57 +151,62 @@ public sealed class BSPrim : BSPhysObject
         // Undo any vehicle properties
         this.VehicleType = (int)Vehicle.TYPE_NONE;
 
-        _scene.TaintedObject("BSPrim.destroy", delegate()
+        PhysicsScene.TaintedObject("BSPrim.destroy", delegate()
         {
             DetailLog("{0},BSPrim.Destroy,taint,", LocalID);
-            // everything in the C# world will get garbage collected. Tell the C++ world to free stuff.
-            BulletSimAPI.DestroyObject(_scene.WorldID, LocalID);
+            // If there are physical body and shape, release my use of same.
+            PhysicsScene.Shapes.DereferenceBody(BSBody, true, null);
+            PhysicsScene.Shapes.DereferenceShape(BSShape, true, null);
         });
     }
-    
-    public override bool Stopped { 
-        get { return _stopped; } 
+
+    public override bool Stopped {
+        get { return _stopped; }
     }
-    public override OMV.Vector3 Size { 
-        get { return _size; } 
+    public override OMV.Vector3 Size {
+        get { return _size; }
         set {
             _size = value;
-            _scene.TaintedObject("BSPrim.setSize", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setSize", delegate()
             {
                 _mass = CalculateMass();   // changing size changes the mass
                 // Since _size changed, the mesh needs to be rebuilt. If rebuilt, all the correct
                 //   scale and margins are set.
                 CreateGeomAndObject(true);
-                DetailLog("{0}: BSPrim.setSize: size={1}, scale={2}, mass={3}, physical={4}", LocalID, _size, _scale, _mass, IsPhysical);
+                // DetailLog("{0},BSPrim.setSize,size={1},scale={2},mass={3},physical={4}", LocalID, _size, _scale, _mass, IsPhysical);
             });
-        } 
+        }
     }
-    public override PrimitiveBaseShape Shape { 
+    // Scale is what we set in the physics engine. It is different than 'size' in that
+    //     'size' can be encorporated into the mesh. In that case, the scale is <1,1,1>.
+    public OMV.Vector3 Scale
+    {
+        get { return _scale; }
+        set { _scale = value; }
+    }
+    public override PrimitiveBaseShape Shape {
         set {
             _pbs = value;
-            _scene.TaintedObject("BSPrim.setShape", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setShape", delegate()
             {
                 _mass = CalculateMass();   // changing the shape changes the mass
-                CreateGeomAndObject(false);
+                CreateGeomAndObject(true);
             });
-        } 
-    }
-    public override uint LocalID { 
-        set { _localID = value; }
-        get { return _localID; }
+        }
     }
-    public override bool Grabbed { 
-        set { _grabbed = value; 
-        } 
+    public override bool Grabbed {
+        set { _grabbed = value;
+        }
     }
-    public override bool Selected { 
+    public override bool Selected {
         set {
             _isSelected = value;
-            _scene.TaintedObject("BSPrim.setSelected", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setSelected", delegate()
             {
-                SetObjectDynamic();
+                // DetailLog("{0},BSPrim.selected,taint,selected={1}", LocalID, _isSelected);
+                SetObjectDynamic(false);
             });
-        } 
+        }
     }
     public override void CrossingFailure() { return; }
 
@@ -232,10 +220,10 @@ public sealed class BSPrim : BSPhysObject
 
             Linkset = parent.Linkset.AddMeToLinkset(this);
 
-            DetailLog("{0},BSPrim.link,call,parentBefore={1}, childrenBefore=={2}, parentAfter={3}, childrenAfter={4}", 
+            DetailLog("{0},BSPrim.link,call,parentBefore={1}, childrenBefore=={2}, parentAfter={3}, childrenAfter={4}",
                 LocalID, parentBefore.LocalID, childrenBefore, Linkset.LinksetRoot.LocalID, Linkset.NumberOfChildren);
         }
-        return; 
+        return;
     }
 
     // delink me from my linkset
@@ -245,12 +233,12 @@ public sealed class BSPrim : BSPhysObject
 
         BSPhysObject parentBefore = Linkset.LinksetRoot;
         int childrenBefore = Linkset.NumberOfChildren;
-        
+
         Linkset = Linkset.RemoveMeFromLinkset(this);
 
-        DetailLog("{0},BSPrim.delink,parentBefore={1},childrenBefore={2},parentAfter={3},childrenAfter={4}, ", 
+        DetailLog("{0},BSPrim.delink,parentBefore={1},childrenBefore={2},parentAfter={3},childrenAfter={4}, ",
             LocalID, parentBefore.LocalID, childrenBefore, Linkset.LinksetRoot.LocalID, Linkset.NumberOfChildren);
-        return; 
+        return;
     }
 
     // Set motion values to zero.
@@ -264,43 +252,40 @@ public sealed class BSPrim : BSPhysObject
         _rotationalVelocity = OMV.Vector3.Zero;
 
         // Zero some other properties directly into the physics engine
-        BulletSimAPI.SetLinearVelocity2(BSBody.Ptr, OMV.Vector3.Zero);
-        BulletSimAPI.SetAngularVelocity2(BSBody.Ptr, OMV.Vector3.Zero);
-        BulletSimAPI.SetInterpolationVelocity2(BSBody.Ptr, OMV.Vector3.Zero, OMV.Vector3.Zero);
-        BulletSimAPI.ClearForces2(BSBody.Ptr);
+        BulletSimAPI.ClearForces2(BSBody.ptr);
     }
 
     public override void LockAngularMotion(OMV.Vector3 axis)
-    { 
+    {
         DetailLog("{0},BSPrim.LockAngularMotion,call,axis={1}", LocalID, axis);
         return;
     }
 
-    public override OMV.Vector3 Position { 
-        get { 
+    public override OMV.Vector3 Position {
+        get {
             if (!Linkset.IsRoot(this))
                 // child prims move around based on their parent. Need to get the latest location
-                _position = BulletSimAPI.GetPosition2(BSBody.Ptr);
+                _position = BulletSimAPI.GetPosition2(BSBody.ptr);
 
             // don't do the GetObjectPosition for root elements because this function is called a zillion times
-            // _position = BulletSimAPI.GetObjectPosition(_scene.WorldID, _localID);
-            return _position; 
-        } 
+            // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
+            return _position;
+        }
         set {
             _position = value;
             // TODO: what does it mean to set the position of a child prim?? Rebuild the constraint?
-            _scene.TaintedObject("BSPrim.setPosition", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setPosition", delegate()
             {
-                DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetTranslation2(BSBody.Ptr, _position, _orientation);
+                // DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
+                BulletSimAPI.SetTranslation2(BSBody.ptr, _position, _orientation);
             });
-        } 
+        }
     }
 
     // Return the effective mass of the object.
     // If there are multiple items in the linkset, add them together for the root
     public override float Mass
-    { 
+    {
         get
         {
             // return Linkset.LinksetMass;
@@ -323,59 +308,59 @@ public sealed class BSPrim : BSPhysObject
         get { return Linkset.GeometricCenter; }
     }
 
-    public override OMV.Vector3 Force { 
-        get { return _force; } 
+    public override OMV.Vector3 Force {
+        get { return _force; }
         set {
             _force = value;
-            _scene.TaintedObject("BSPrim.setForce", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setForce", delegate()
             {
-                DetailLog("{0},BSPrim.setForce,taint,force={1}", LocalID, _force);
-                BulletSimAPI.SetObjectForce2(BSBody.Ptr, _force);
+                // DetailLog("{0},BSPrim.setForce,taint,force={1}", LocalID, _force);
+                BulletSimAPI.SetObjectForce2(BSBody.ptr, _force);
             });
-        } 
+        }
     }
 
-    public override int VehicleType { 
+    public override int VehicleType {
         get {
             return (int)_vehicle.Type;   // if we are a vehicle, return that type
-        } 
+        }
         set {
             Vehicle type = (Vehicle)value;
             BSPrim vehiclePrim = this;
-            _scene.TaintedObject("setVehicleType", delegate()
+            PhysicsScene.TaintedObject("setVehicleType", delegate()
             {
                 // Done at taint time so we're sure the physics engine is not using the variables
                 // Vehicle code changes the parameters for this vehicle type.
                 _vehicle.ProcessTypeChange(type);
                 // Tell the scene about the vehicle so it will get processing each frame.
-                _scene.VehicleInSceneTypeChanged(this, type);
+                PhysicsScene.VehicleInSceneTypeChanged(this, type);
             });
-        } 
+        }
     }
-    public override void VehicleFloatParam(int param, float value) 
+    public override void VehicleFloatParam(int param, float value)
     {
-        _scene.TaintedObject("BSPrim.VehicleFloatParam", delegate()
+        PhysicsScene.TaintedObject("BSPrim.VehicleFloatParam", delegate()
         {
             _vehicle.ProcessFloatVehicleParam((Vehicle)param, value);
         });
     }
-    public override void VehicleVectorParam(int param, OMV.Vector3 value) 
+    public override void VehicleVectorParam(int param, OMV.Vector3 value)
     {
-        _scene.TaintedObject("BSPrim.VehicleVectorParam", delegate()
+        PhysicsScene.TaintedObject("BSPrim.VehicleVectorParam", delegate()
         {
             _vehicle.ProcessVectorVehicleParam((Vehicle)param, value);
         });
     }
-    public override void VehicleRotationParam(int param, OMV.Quaternion rotation) 
+    public override void VehicleRotationParam(int param, OMV.Quaternion rotation)
     {
-        _scene.TaintedObject("BSPrim.VehicleRotationParam", delegate()
+        PhysicsScene.TaintedObject("BSPrim.VehicleRotationParam", delegate()
         {
             _vehicle.ProcessRotationVehicleParam((Vehicle)param, rotation);
         });
     }
-    public override void VehicleFlags(int param, bool remove) 
+    public override void VehicleFlags(int param, bool remove)
     {
-        _scene.TaintedObject("BSPrim.VehicleFlags", delegate()
+        PhysicsScene.TaintedObject("BSPrim.VehicleFlags", delegate()
         {
             _vehicle.ProcessVehicleFlags(param, remove);
         });
@@ -392,73 +377,81 @@ public sealed class BSPrim : BSPhysObject
     // Allows the detection of collisions with inherently non-physical prims. see llVolumeDetect for more
     public override void SetVolumeDetect(int param) {
         bool newValue = (param != 0);
-        _isVolumeDetect = newValue;
-        _scene.TaintedObject("BSPrim.SetVolumeDetect", delegate()
+        if (_isVolumeDetect != newValue)
         {
-            SetObjectDynamic();
-        });
-        return; 
+            _isVolumeDetect = newValue;
+            PhysicsScene.TaintedObject("BSPrim.SetVolumeDetect", delegate()
+            {
+                // DetailLog("{0},setVolumeDetect,taint,volDetect={1}", LocalID, _isVolumeDetect);
+                SetObjectDynamic(true);
+            });
+        }
+        return;
     }
 
-    public override OMV.Vector3 Velocity { 
-        get { return _velocity; } 
+    public override OMV.Vector3 Velocity {
+        get { return _velocity; }
         set {
             _velocity = value;
-            _scene.TaintedObject("BSPrim.setVelocity", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setVelocity", delegate()
             {
-                DetailLog("{0},BSPrim.SetVelocity,taint,vel={1}", LocalID, _velocity);
-                BulletSimAPI.SetLinearVelocity2(BSBody.Ptr, _velocity);
+                // DetailLog("{0},BSPrim.SetVelocity,taint,vel={1}", LocalID, _velocity);
+                BulletSimAPI.SetLinearVelocity2(BSBody.ptr, _velocity);
             });
-        } 
+        }
     }
-    public override OMV.Vector3 Torque { 
-        get { return _torque; } 
-        set { _torque = value; 
-            DetailLog("{0},BSPrim.SetTorque,call,torque={1}", LocalID, _torque);
-        } 
+    public override OMV.Vector3 Torque {
+        get { return _torque; }
+        set { _torque = value;
+            // DetailLog("{0},BSPrim.SetTorque,call,torque={1}", LocalID, _torque);
+        }
     }
-    public override float CollisionScore { 
-        get { return _collisionScore; } 
-        set { _collisionScore = value; 
-        } 
+    public override float CollisionScore {
+        get { return _collisionScore; }
+        set { _collisionScore = value;
+        }
     }
-    public override OMV.Vector3 Acceleration { 
+    public override OMV.Vector3 Acceleration {
         get { return _acceleration; }
         set { _acceleration = value; }
     }
-    public override OMV.Quaternion Orientation { 
+    public override OMV.Quaternion Orientation {
         get {
             if (!Linkset.IsRoot(this))
             {
                 // Children move around because tied to parent. Get a fresh value.
-                _orientation = BulletSimAPI.GetOrientation2(BSBody.Ptr);
+                _orientation = BulletSimAPI.GetOrientation2(BSBody.ptr);
             }
             return _orientation;
-        } 
+        }
         set {
             _orientation = value;
             // TODO: what does it mean if a child in a linkset changes its orientation? Rebuild the constraint?
-            _scene.TaintedObject("BSPrim.setOrientation", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setOrientation", delegate()
             {
-                // _position = BulletSimAPI.GetObjectPosition(_scene.WorldID, _localID);
-                DetailLog("{0},BSPrim.setOrientation,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetTranslation2(BSBody.Ptr, _position, _orientation);
+                // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
+                // DetailLog("{0},BSPrim.setOrientation,taint,pos={1},orient={2}", LocalID, _position, _orientation);
+                BulletSimAPI.SetTranslation2(BSBody.ptr, _position, _orientation);
             });
-        } 
+        }
     }
-    public override int PhysicsActorType { 
-        get { return _physicsActorType; } 
-        set { _physicsActorType = value; } 
+    public override int PhysicsActorType {
+        get { return _physicsActorType; }
+        set { _physicsActorType = value; }
     }
-    public override bool IsPhysical { 
-        get { return _isPhysical; } 
+    public override bool IsPhysical {
+        get { return _isPhysical; }
         set {
-            _isPhysical = value;
-            _scene.TaintedObject("BSPrim.setIsPhysical", delegate()
+            if (_isPhysical != value)
             {
-                SetObjectDynamic();
-            });
-        } 
+                _isPhysical = value;
+                PhysicsScene.TaintedObject("BSPrim.setIsPhysical", delegate()
+                {
+                    // DetailLog("{0},setIsPhysical,taint,isPhys={1}", LocalID, _isPhysical);
+                    SetObjectDynamic(true);
+                });
+            }
+        }
     }
 
     // An object is static (does not move) if selected or not physical
@@ -468,53 +461,64 @@ public sealed class BSPrim : BSPhysObject
     }
 
     // An object is solid if it's not phantom and if it's not doing VolumeDetect
-    private bool IsSolid
+    public bool IsSolid
     {
         get { return !IsPhantom && !_isVolumeDetect; }
     }
 
     // Make gravity work if the object is physical and not selected
-    // No locking here because only called when it is safe
+    // Called at taint-time!!
+    private void SetObjectDynamic(bool forceRebuild)
+    {
+        // Recreate the physical object if necessary
+        CreateGeomAndObject(forceRebuild);
+    }
+
+    // Convert the simulator's physical properties into settings on BulletSim objects.
     // There are four flags we're interested in:
     //     IsStatic: Object does not move, otherwise the object has mass and moves
     //     isSolid: other objects bounce off of this object
     //     isVolumeDetect: other objects pass through but can generate collisions
     //     collisionEvents: whether this object returns collision events
-    private void SetObjectDynamic()
-    {
-        // If it's becoming dynamic, it will need hullness
-        VerifyCorrectPhysicalShape();
-        UpdatePhysicalParameters();
-    }
-
     private void UpdatePhysicalParameters()
     {
-        /*
-        // Bullet wants static objects to have a mass of zero
-        float mass = IsStatic ? 0f : _mass;
+        // DetailLog("{0},BSPrim.UpdatePhysicalParameters,entry,body={1},shape={2}", LocalID, BSBody, BSShape);
+
+        // Mangling all the physical properties requires the object not be in the physical world.
+        // This is a NOOP if the object is not in the world (BulletSim and Bullet ignore objects not found).
+        BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, BSBody.ptr);
 
-        BulletSimAPI.SetObjectProperties(_scene.WorldID, LocalID, IsStatic, IsSolid, SubscribedEvents(), mass);
-         */
-        BulletSimAPI.RemoveObjectFromWorld2(Scene.World.Ptr, BSBody.Ptr);
 
         // Set up the object physicalness (does gravity and collisions move this object)
         MakeDynamic(IsStatic);
 
-        // Make solid or not (do things bounce off or pass through this object)
-        MakeSolid(IsSolid);
+        // Do any vehicle stuff
+        _vehicle.Refresh();
 
-        // Arrange for collisions events if the simulator wants them
+        // Arrange for collision events if the simulator wants them
         EnableCollisions(SubscribedEvents());
 
-        BulletSimAPI.AddObjectToWorld2(Scene.World.Ptr, BSBody.Ptr);
+        // Make solid or not (do things bounce off or pass through this object).
+        MakeSolid(IsSolid);
+
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, BSBody.ptr);
+
+        // Rebuild its shape
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, BSBody.ptr);
+
+        // Collision filter can be set only when the object is in the world
+        if (BSBody.collisionFilter != 0 || BSBody.collisionMask != 0)
+        {
+            BulletSimAPI.SetCollisionFilterMask2(BSBody.ptr, (uint)BSBody.collisionFilter, (uint)BSBody.collisionMask);
+        }
 
         // Recompute any linkset parameters.
         // When going from non-physical to physical, this re-enables the constraints that
         //     had been automatically disabled when the mass was set to zero.
         Linkset.Refresh(this);
 
-        DetailLog("{0},BSPrim.UpdatePhysicalParameters,taint,static={1},solid={2},mass={3}, cf={4}", 
-                        LocalID, IsStatic, IsSolid, _mass, m_currentCollisionFlags);
+        DetailLog("{0},BSPrim.UpdatePhysicalParameters,exit,static={1},solid={2},mass={3},collide={4},cf={5:X},body={6},shape={7}",
+                        LocalID, IsStatic, IsSolid, _mass, SubscribedEvents(), CurrentCollisionFlags, BSBody, BSShape);
     }
 
     // "Making dynamic" means changing to and from static.
@@ -527,65 +531,86 @@ public sealed class BSPrim : BSPhysObject
         if (makeStatic)
         {
             // Become a Bullet 'static' object type
-            m_currentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.Ptr, CollisionFlags.CF_STATIC_OBJECT);
+            CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
             // Stop all movement
-            BulletSimAPI.ClearAllForces2(BSBody.Ptr);
+            BulletSimAPI.ClearAllForces2(BSBody.ptr);
             // Center of mass is at the center of the object
-            BulletSimAPI.SetCenterOfMassByPosRot2(Linkset.LinksetRoot.BSBody.Ptr, _position, _orientation);
+            BulletSimAPI.SetCenterOfMassByPosRot2(Linkset.LinksetRoot.BSBody.ptr, _position, _orientation);
             // Mass is zero which disables a bunch of physics stuff in Bullet
-            BulletSimAPI.SetMassProps2(BSBody.Ptr, 0f, OMV.Vector3.Zero);
+            BulletSimAPI.SetMassProps2(BSBody.ptr, 0f, OMV.Vector3.Zero);
             // There is no inertia in a static object
-            BulletSimAPI.UpdateInertiaTensor2(BSBody.Ptr);
+            BulletSimAPI.UpdateInertiaTensor2(BSBody.ptr);
             // There can be special things needed for implementing linksets
             Linkset.MakeStatic(this);
-            // The activation state is 'sleeping' so Bullet will not try to act on it
-            BulletSimAPI.ForceActivationState2(BSBody.Ptr, ActivationState.ISLAND_SLEEPING);
+            // The activation state is 'disabled' so Bullet will not try to act on it
+            BulletSimAPI.ForceActivationState2(BSBody.ptr, ActivationState.DISABLE_SIMULATION);
+
+            BSBody.collisionFilter = CollisionFilterGroups.StaticObjectFilter;
+            BSBody.collisionMask = CollisionFilterGroups.StaticObjectMask;
         }
         else
         {
             // Not a Bullet static object
-            m_currentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.Ptr, CollisionFlags.CF_STATIC_OBJECT);
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+            // Set various physical properties so internal dynamic properties will get computed correctly as they are set
+            BulletSimAPI.SetFriction2(BSBody.ptr, PhysicsScene.Params.defaultFriction);
+            BulletSimAPI.SetRestitution2(BSBody.ptr, PhysicsScene.Params.defaultRestitution);
 
-            // Set various physical properties so internal things will get computed correctly as they are set
-            BulletSimAPI.SetFriction2(BSBody.Ptr, Scene.Params.defaultFriction);
-            BulletSimAPI.SetRestitution2(BSBody.Ptr, Scene.Params.defaultRestitution);
             // per http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=3382
-            BulletSimAPI.SetInterpolationLinearVelocity2(BSBody.Ptr, OMV.Vector3.Zero);
-            BulletSimAPI.SetInterpolationAngularVelocity2(BSBody.Ptr, OMV.Vector3.Zero);
-            BulletSimAPI.SetInterpolationVelocity2(BSBody.Ptr, OMV.Vector3.Zero, OMV.Vector3.Zero);
+            BulletSimAPI.ClearAllForces2(BSBody.ptr);
 
             // A dynamic object has mass
-            IntPtr collisionShapePtr = BulletSimAPI.GetCollisionShape2(BSBody.Ptr);
-            OMV.Vector3 inertia = BulletSimAPI.CalculateLocalInertia2(collisionShapePtr, Linkset.LinksetMass);
-            BulletSimAPI.SetMassProps2(BSBody.Ptr, _mass, inertia);
-            // Inertia is based on our new mass
-            BulletSimAPI.UpdateInertiaTensor2(BSBody.Ptr);
+            IntPtr collisionShapePtr = BulletSimAPI.GetCollisionShape2(BSBody.ptr);
+            OMV.Vector3 inertia = BulletSimAPI.CalculateLocalInertia2(collisionShapePtr, Mass);
+            // OMV.Vector3 inertia = OMV.Vector3.Zero;
+            BulletSimAPI.SetMassProps2(BSBody.ptr, _mass, inertia);
+            BulletSimAPI.UpdateInertiaTensor2(BSBody.ptr);
 
             // Various values for simulation limits
-            BulletSimAPI.SetDamping2(BSBody.Ptr, Scene.Params.linearDamping, Scene.Params.angularDamping);
-            BulletSimAPI.SetDeactivationTime2(BSBody.Ptr, Scene.Params.deactivationTime);
-            BulletSimAPI.SetSleepingThresholds2(BSBody.Ptr, Scene.Params.linearSleepingThreshold, Scene.Params.angularSleepingThreshold);
-            BulletSimAPI.SetContactProcessingThreshold2(BSBody.Ptr, Scene.Params.contactProcessingThreshold);
+            BulletSimAPI.SetDamping2(BSBody.ptr, PhysicsScene.Params.linearDamping, PhysicsScene.Params.angularDamping);
+            BulletSimAPI.SetDeactivationTime2(BSBody.ptr, PhysicsScene.Params.deactivationTime);
+            BulletSimAPI.SetSleepingThresholds2(BSBody.ptr, PhysicsScene.Params.linearSleepingThreshold, PhysicsScene.Params.angularSleepingThreshold);
+            BulletSimAPI.SetContactProcessingThreshold2(BSBody.ptr, PhysicsScene.Params.contactProcessingThreshold);
 
-            // There can be special things needed for implementing linksets
+            // There can be special things needed for implementing linksets.
             Linkset.MakeDynamic(this);
 
             // Force activation of the object so Bullet will act on it.
-            BulletSimAPI.Activate2(BSBody.Ptr, true);
+            // Must do the ForceActivationState2() to overcome the DISABLE_SIMULATION from static objects.
+            BulletSimAPI.ForceActivationState2(BSBody.ptr, ActivationState.ISLAND_SLEEPING);
+            BulletSimAPI.Activate2(BSBody.ptr, true);
+
+            BSBody.collisionFilter = CollisionFilterGroups.ObjectFilter;
+            BSBody.collisionMask = CollisionFilterGroups.ObjectMask;
         }
     }
 
     // "Making solid" means that other object will not pass through this object.
+    // To make transparent, we create a Bullet ghost object.
+    // Note: This expects to be called from the UpdatePhysicalParameters() routine as
+    //     the functions after this one set up the state of a possibly newly created collision body.
     private void MakeSolid(bool makeSolid)
     {
+        CollisionObjectTypes bodyType = (CollisionObjectTypes)BulletSimAPI.GetBodyType2(BSBody.ptr);
         if (makeSolid)
         {
-            // Easy in Bullet -- just remove the object flag that controls collision response
-            m_currentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.Ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
+            // Verify the previous code created the correct shape for this type of thing.
+            if ((bodyType & CollisionObjectTypes.CO_RIGID_BODY) == 0)
+            {
+                m_log.ErrorFormat("{0} MakeSolid: physical body of wrong type for solidity. id={1}, type={2}", LogHeader, LocalID, bodyType);
+            }
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
         }
         else
         {
-            m_currentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.Ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
+            if ((bodyType & CollisionObjectTypes.CO_GHOST_OBJECT) == 0)
+            {
+                m_log.ErrorFormat("{0} MakeSolid: physical body of wrong type for non-solidness. id={1}, type={2}", LogHeader, LocalID, bodyType);
+            }
+            CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
+            BSBody.collisionFilter = CollisionFilterGroups.VolumeDetectFilter;
+            BSBody.collisionMask = CollisionFilterGroups.VolumeDetectMask;
         }
     }
 
@@ -594,40 +619,40 @@ public sealed class BSPrim : BSPhysObject
     {
         if (wantsCollisionEvents)
         {
-            m_currentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+            CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
         }
         else
         {
-            m_currentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
         }
     }
 
     // prims don't fly
-    public override bool Flying { 
-        get { return _flying; } 
+    public override bool Flying {
+        get { return _flying; }
         set {
             _flying = value;
-        } 
+        }
     }
-    public override bool SetAlwaysRun { 
-        get { return _setAlwaysRun; } 
-        set { _setAlwaysRun = value; } 
+    public override bool SetAlwaysRun {
+        get { return _setAlwaysRun; }
+        set { _setAlwaysRun = value; }
     }
-    public override bool ThrottleUpdates { 
-        get { return _throttleUpdates; } 
-        set { _throttleUpdates = value; } 
+    public override bool ThrottleUpdates {
+        get { return _throttleUpdates; }
+        set { _throttleUpdates = value; }
     }
     public override bool IsColliding {
-        get { return (_collidingStep == _scene.SimulationStep); } 
-        set { _isColliding = value; } 
+        get { return (CollidingStep == PhysicsScene.SimulationStep); }
+        set { _isColliding = value; }
     }
     public override bool CollidingGround {
-        get { return (_collidingGroundStep == _scene.SimulationStep); } 
-        set { _collidingGround = value; } 
+        get { return (CollidingGroundStep == PhysicsScene.SimulationStep); }
+        set { _collidingGround = value; }
     }
-    public override bool CollidingObj { 
-        get { return _collidingObj; } 
-        set { _collidingObj = value; } 
+    public override bool CollidingObj {
+        get { return _collidingObj; }
+        set { _collidingObj = value; }
     }
     public bool IsPhantom {
         get {
@@ -637,10 +662,10 @@ public sealed class BSPrim : BSPhysObject
             return false;
         }
     }
-    public override bool FloatOnWater { 
-        set { _floatOnWater = value; } 
+    public override bool FloatOnWater {
+        set { _floatOnWater = value; }
     }
-    public override OMV.Vector3 RotationalVelocity { 
+    public override OMV.Vector3 RotationalVelocity {
         get {
             /*
             OMV.Vector3 pv = OMV.Vector3.Zero;
@@ -652,61 +677,60 @@ public sealed class BSPrim : BSPhysObject
              */
 
             return _rotationalVelocity;
-        } 
+        }
         set {
             _rotationalVelocity = value;
             // m_log.DebugFormat("{0}: RotationalVelocity={1}", LogHeader, _rotationalVelocity);
-            _scene.TaintedObject("BSPrim.setRotationalVelocity", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setRotationalVelocity", delegate()
             {
-                DetailLog("{0},BSPrim.SetRotationalVel,taint,rotvel={1}", LocalID, _rotationalVelocity);
-                BulletSimAPI.SetAngularVelocity2(BSBody.Ptr, _rotationalVelocity);
+                // DetailLog("{0},BSPrim.SetRotationalVel,taint,rotvel={1}", LocalID, _rotationalVelocity);
+                BulletSimAPI.SetAngularVelocity2(BSBody.ptr, _rotationalVelocity);
             });
-        } 
+        }
     }
-    public override bool Kinematic { 
-        get { return _kinematic; } 
-        set { _kinematic = value; 
+    public override bool Kinematic {
+        get { return _kinematic; }
+        set { _kinematic = value;
             // m_log.DebugFormat("{0}: Kinematic={1}", LogHeader, _kinematic);
-        } 
+        }
     }
-    public override float Buoyancy { 
-        get { return _buoyancy; } 
+    public override float Buoyancy {
+        get { return _buoyancy; }
         set {
             _buoyancy = value;
-            _scene.TaintedObject("BSPrim.setBuoyancy", delegate()
+            PhysicsScene.TaintedObject("BSPrim.setBuoyancy", delegate()
             {
-                DetailLog("{0},BSPrim.SetBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
+                // DetailLog("{0},BSPrim.SetBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
                 // Buoyancy is faked by changing the gravity applied to the object
-                float grav = Scene.Params.gravity * (1f - _buoyancy);
-                BulletSimAPI.SetGravity2(BSBody.Ptr, new OMV.Vector3(0f, 0f, grav));
-                // BulletSimAPI.SetObjectBuoyancy(_scene.WorldID, _localID, _buoyancy);
+                float grav = PhysicsScene.Params.gravity * (1f - _buoyancy);
+                BulletSimAPI.SetGravity2(BSBody.ptr, new OMV.Vector3(0f, 0f, grav));
             });
-        } 
+        }
     }
 
     // Used for MoveTo
-    public override OMV.Vector3 PIDTarget { 
-        set { _PIDTarget = value; } 
+    public override OMV.Vector3 PIDTarget {
+        set { _PIDTarget = value; }
     }
-    public override bool PIDActive { 
-        set { _usePID = value; } 
+    public override bool PIDActive {
+        set { _usePID = value; }
     }
-    public override float PIDTau { 
-        set { _PIDTau = value; } 
+    public override float PIDTau {
+        set { _PIDTau = value; }
     }
 
     // Used for llSetHoverHeight and maybe vehicle height
     // Hover Height will override MoveTo target's Z
-    public override bool PIDHoverActive { 
+    public override bool PIDHoverActive {
         set { _useHoverPID = value; }
     }
-    public override float PIDHoverHeight { 
+    public override float PIDHoverHeight {
         set { _PIDHoverHeight = value; }
     }
-    public override PIDHoverType PIDHoverType { 
+    public override PIDHoverType PIDHoverType {
         set { _PIDHoverType = value; }
     }
-    public override float PIDHoverTau { 
+    public override float PIDHoverTau {
         set { _PIDHoverTao = value; }
     }
 
@@ -730,7 +754,7 @@ public sealed class BSPrim : BSPhysObject
             m_log.WarnFormat("{0}: Got a NaN force applied to a prim. LocalID={1}", LogHeader, LocalID);
             return;
         }
-        _scene.TaintedObject("BSPrim.AddForce", delegate()
+        PhysicsScene.TaintedObject("BSPrim.AddForce", delegate()
         {
             OMV.Vector3 fSum = OMV.Vector3.Zero;
             lock (m_accumulatedForces)
@@ -741,43 +765,19 @@ public sealed class BSPrim : BSPhysObject
                 }
                 m_accumulatedForces.Clear();
             }
-            DetailLog("{0},BSPrim.AddObjectForce,taint,force={1}", LocalID, fSum);
+            // DetailLog("{0},BSPrim.AddObjectForce,taint,force={1}", LocalID, fSum);
             // For unknown reasons, "ApplyCentralForce" adds this force to the total force on the object.
-            BulletSimAPI.ApplyCentralForce2(BSBody.Ptr, fSum);
+            BulletSimAPI.ApplyCentralForce2(BSBody.ptr, fSum);
         });
     }
 
-    public override void AddAngularForce(OMV.Vector3 force, bool pushforce) { 
-        DetailLog("{0},BSPrim.AddAngularForce,call,angForce={1},push={2}", LocalID, force, pushforce);
+    public override void AddAngularForce(OMV.Vector3 force, bool pushforce) {
+        // DetailLog("{0},BSPrim.AddAngularForce,call,angForce={1},push={2}", LocalID, force, pushforce);
         // m_log.DebugFormat("{0}: AddAngularForce. f={1}, push={2}", LogHeader, force, pushforce);
     }
-    public override void SetMomentum(OMV.Vector3 momentum) { 
-        DetailLog("{0},BSPrim.SetMomentum,call,mom={1}", LocalID, momentum);
+    public override void SetMomentum(OMV.Vector3 momentum) {
+        // DetailLog("{0},BSPrim.SetMomentum,call,mom={1}", LocalID, momentum);
     }
-    public override void SubscribeEvents(int ms) { 
-        _subscribedEventsMs = ms;
-        if (ms > 0)
-        {
-            // make sure first collision happens
-            _nextCollisionOkTime = Util.EnvironmentTickCount() - _subscribedEventsMs;
-
-            Scene.TaintedObject("BSPrim.SubscribeEvents", delegate()
-            {
-                m_currentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
-            });
-        }
-    }
-    public override void UnSubscribeEvents() { 
-        _subscribedEventsMs = 0;
-        Scene.TaintedObject("BSPrim.UnSubscribeEvents", delegate()
-        {
-            m_currentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(BSBody.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
-        });
-    }
-    public override bool SubscribedEvents() { 
-        return (_subscribedEventsMs > 0);
-    }
-
     #region Mass Calculation
 
     private float CalculateMass()
@@ -787,8 +787,8 @@ public sealed class BSPrim : BSPhysObject
 
         float returnMass = 0;
         float hollowAmount = (float)_pbs.ProfileHollow * 2.0e-5f;
-        float hollowVolume = hollowAmount * hollowAmount; 
-        
+        float hollowVolume = hollowAmount * hollowAmount;
+
         switch (_pbs.ProfileShape)
         {
             case ProfileShape.Square:
@@ -824,16 +824,16 @@ public sealed class BSPrim : BSPhysObject
 
                 else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
                     {
-                    //a tube 
+                    //a tube
 
                     volume *= 0.78539816339e-2f * (float)(200 - _pbs.PathScaleX);
                     tmp= 1.0f -2.0e-2f * (float)(200 - _pbs.PathScaleY);
                     volume -= volume*tmp*tmp;
-                    
+
                     if (hollowAmount > 0.0)
                         {
                         hollowVolume *= hollowAmount;
-                        
+   
                         switch (_pbs.HollowShape)
                             {
                             case HollowShape.Square:
@@ -892,7 +892,7 @@ public sealed class BSPrim : BSPhysObject
                     volume *= 0.61685027506808491367715568749226e-2f * (float)(200 - _pbs.PathScaleX);
                     tmp = 1.0f - .02f * (float)(200 - _pbs.PathScaleY);
                     volume *= (1.0f - tmp * tmp);
-                    
+
                     if (hollowAmount > 0.0)
                         {
 
@@ -1071,302 +1071,17 @@ public sealed class BSPrim : BSPhysObject
         if (returnMass <= 0)
             returnMass = 0.0001f;
 
-        if (returnMass > _scene.MaximumObjectMass)
-            returnMass = _scene.MaximumObjectMass;
+        if (returnMass > PhysicsScene.MaximumObjectMass)
+            returnMass = PhysicsScene.MaximumObjectMass;
 
         return returnMass;
     }// end CalculateMass
     #endregion Mass Calculation
 
-    // Create the geometry information in Bullet for later use.
-    // The objects needs a hull if it's physical otherwise a mesh is enough.
-    // No locking here because this is done when we know physics is not simulating.
-    // if 'forceRebuild' is true, the geometry is rebuilt. Otherwise a previously built version is used.
-    // Returns 'true' if the geometry was rebuilt.
-    // Called at taint-time!
-    private bool CreateGeom(bool forceRebuild)
-    {
-        bool ret = false;
-        bool haveShape = false;
-
-        // If the prim attributes are simple, this could be a simple Bullet native shape
-        if ((_pbs.SculptEntry && !Scene.ShouldMeshSculptedPrim)
-                || (_pbs.ProfileBegin == 0 && _pbs.ProfileEnd == 0
-                    && _pbs.ProfileHollow == 0
-                    && _pbs.PathTwist == 0 && _pbs.PathTwistBegin == 0
-                    && _pbs.PathBegin == 0 && _pbs.PathEnd == 0
-                    && _pbs.PathTaperX == 0 && _pbs.PathTaperY == 0
-                    && _pbs.PathScaleX == 100 && _pbs.PathScaleY == 100
-                    && _pbs.PathShearX == 0 && _pbs.PathShearY == 0) )
-        {
-            if (_pbs.ProfileShape == ProfileShape.HalfCircle && _pbs.PathCurve == (byte)Extrusion.Curve1)
-            {
-                haveShape = true;
-                if (forceRebuild || (_shapeType != ShapeData.PhysicsShapeType.SHAPE_SPHERE))
-                {
-                    DetailLog("{0},BSPrim.CreateGeom,sphere (force={1}", LocalID, forceRebuild);
-                    _shapeType = ShapeData.PhysicsShapeType.SHAPE_SPHERE;
-                    // Bullet native objects are scaled by the Bullet engine so pass the size in
-                    _scale = _size;
-                    // TODO: do we need to check for and destroy a mesh or hull that might have been left from before?
-                    ret = true;
-                }
-            }
-            else
-            {
-                // m_log.DebugFormat("{0}: CreateGeom: Defaulting to box. lid={1}, type={2}, size={3}", LogHeader, LocalID, _shapeType, _size);
-                haveShape = true;
-                if (forceRebuild || (_shapeType != ShapeData.PhysicsShapeType.SHAPE_BOX))
-                {
-                    DetailLog("{0},BSPrim.CreateGeom,box (force={1})", LocalID, forceRebuild);
-                    _shapeType = ShapeData.PhysicsShapeType.SHAPE_BOX;
-                    _scale = _size;
-                    // TODO: do we need to check for and destroy a mesh or hull that might have been left from before?
-                    ret = true;
-                }
-            }
-        }
-        // If a simple shape isn't happening, create a mesh and possibly a hull
-        if (!haveShape)
-        {
-            if (IsPhysical)
-            {
-                if (forceRebuild || _hullKey == 0)
-                {
-                    // physical objects require a hull for interaction.
-                    // This also creates the mesh if it doesn't already exist
-                    ret = CreateGeomHull();
-                }
-            }
-            else
-            {
-                if (forceRebuild || _meshKey == 0)
-                {
-                    // Static (non-physical) objects only need a mesh for bumping into
-                    ret = CreateGeomMesh();
-                }
-            }
-        }
-        return ret;
-    }
-
-    // No locking here because this is done when we know physics is not simulating
-    // Returns 'true' of a mesh was actually rebuild (we could also have one of these specs).
-    // Called at taint-time!
-    private bool CreateGeomMesh()
-    {
-        // level of detail based on size and type of the object
-        float lod = _scene.MeshLOD;
-        if (_pbs.SculptEntry) 
-            lod = _scene.SculptLOD;
-        float maxAxis = Math.Max(_size.X, Math.Max(_size.Y, _size.Z));
-        if (maxAxis > _scene.MeshMegaPrimThreshold) 
-            lod = _scene.MeshMegaPrimLOD;
-
-        ulong newMeshKey = (ulong)_pbs.GetMeshKey(_size, lod);
-        // m_log.DebugFormat("{0}: CreateGeomMesh: lID={1}, oldKey={2}, newKey={3}", LogHeader, _localID, _meshKey, newMeshKey);
-
-        // if this new shape is the same as last time, don't recreate the mesh
-        if (_meshKey == newMeshKey) return false;
-
-        DetailLog("{0},BSPrim.CreateGeomMesh,create,key={1}", LocalID, newMeshKey);
-        // Since we're recreating new, get rid of any previously generated shape
-        if (_meshKey != 0)
-        {
-            // m_log.DebugFormat("{0}: CreateGeom: deleting old mesh. lID={1}, Key={2}", LogHeader, _localID, _meshKey);
-            DetailLog("{0},BSPrim.CreateGeomMesh,deleteOld,key={1}", LocalID, _meshKey);
-            BulletSimAPI.DestroyMesh(_scene.WorldID, _meshKey);
-            _mesh = null;
-            _meshKey = 0;
-        }
-
-        _meshKey = newMeshKey;
-        // always pass false for physicalness as this creates some sort of bounding box which we don't need
-        _mesh = _scene.mesher.CreateMesh(_avName, _pbs, _size, lod, false);
-
-        int[] indices = _mesh.getIndexListAsInt();
-        List<OMV.Vector3> vertices = _mesh.getVertexList();
-
-        float[] verticesAsFloats = new float[vertices.Count * 3];
-        int vi = 0;
-        foreach (OMV.Vector3 vv in vertices)
-        {
-            verticesAsFloats[vi++] = vv.X;
-            verticesAsFloats[vi++] = vv.Y;
-            verticesAsFloats[vi++] = vv.Z;
-        }
-
-        // m_log.DebugFormat("{0}: CreateGeomMesh: calling CreateMesh. lid={1}, key={2}, indices={3}, vertices={4}", 
-        //                  LogHeader, _localID, _meshKey, indices.Length, vertices.Count);
-        BulletSimAPI.CreateMesh(_scene.WorldID, _meshKey, indices.GetLength(0), indices, 
-                                                        vertices.Count, verticesAsFloats);
-
-        _shapeType = ShapeData.PhysicsShapeType.SHAPE_MESH;
-        // meshes are already scaled by the meshmerizer
-        _scale = new OMV.Vector3(1f, 1f, 1f);
-        return true;
-    }
-
-    // No locking here because this is done when we know physics is not simulating
-    // Returns 'true' of a mesh was actually rebuild (we could also have one of these specs).
-    private bool CreateGeomHull()
-    {
-        float lod = _pbs.SculptEntry ? _scene.SculptLOD : _scene.MeshLOD;
-        ulong newHullKey = (ulong)_pbs.GetMeshKey(_size, lod);
-        // m_log.DebugFormat("{0}: CreateGeomHull: lID={1}, oldKey={2}, newKey={3}", LogHeader, _localID, _hullKey, newHullKey);
-
-        // if the hull hasn't changed, don't rebuild it
-        if (newHullKey == _hullKey) return false;
-
-        DetailLog("{0},BSPrim.CreateGeomHull,create,oldKey={1},newKey={2}", LocalID, _hullKey, newHullKey);
-        
-        // Since we're recreating new, get rid of any previously generated shape
-        if (_hullKey != 0)
-        {
-            // m_log.DebugFormat("{0}: CreateGeom: deleting old hull. Key={1}", LogHeader, _hullKey);
-            DetailLog("{0},BSPrim.CreateGeomHull,deleteOldHull,key={1}", LocalID, _hullKey);
-            BulletSimAPI.DestroyHull(_scene.WorldID, _hullKey);
-            _hullKey = 0;
-        }
-
-        _hullKey = newHullKey;
-
-        // Make sure the underlying mesh exists and is correct
-        CreateGeomMesh();
-
-        int[] indices = _mesh.getIndexListAsInt();
-        List<OMV.Vector3> vertices = _mesh.getVertexList();
-
-        //format conversion from IMesh format to DecompDesc format
-        List<int> convIndices = new List<int>();
-        List<float3> convVertices = new List<float3>();
-        for (int ii = 0; ii < indices.GetLength(0); ii++)
-        {
-            convIndices.Add(indices[ii]);
-        }
-        foreach (OMV.Vector3 vv in vertices)
-        {
-            convVertices.Add(new float3(vv.X, vv.Y, vv.Z));
-        }
-
-        // setup and do convex hull conversion
-        _hulls = new List<ConvexResult>();
-        DecompDesc dcomp = new DecompDesc();
-        dcomp.mIndices = convIndices;
-        dcomp.mVertices = convVertices;
-        ConvexBuilder convexBuilder = new ConvexBuilder(HullReturn);
-        // create the hull into the _hulls variable
-        convexBuilder.process(dcomp);
-
-        // Convert the vertices and indices for passing to unmanaged.
-        // The hull information is passed as a large floating point array. 
-        // The format is:
-        //  convHulls[0] = number of hulls
-        //  convHulls[1] = number of vertices in first hull
-        //  convHulls[2] = hull centroid X coordinate
-        //  convHulls[3] = hull centroid Y coordinate
-        //  convHulls[4] = hull centroid Z coordinate
-        //  convHulls[5] = first hull vertex X
-        //  convHulls[6] = first hull vertex Y
-        //  convHulls[7] = first hull vertex Z
-        //  convHulls[8] = second hull vertex X
-        //  ...
-        //  convHulls[n] = number of vertices in second hull
-        //  convHulls[n+1] = second hull centroid X coordinate
-        //  ...
-        //
-        // TODO: is is very inefficient. Someday change the convex hull generator to return
-        //   data structures that do not need to be converted in order to pass to Bullet.
-        //   And maybe put the values directly into pinned memory rather than marshaling.
-        int hullCount = _hulls.Count;
-        int totalVertices = 1;          // include one for the count of the hulls
-        foreach (ConvexResult cr in _hulls)
-        {
-            totalVertices += 4;                         // add four for the vertex count and centroid
-            totalVertices += cr.HullIndices.Count * 3;  // we pass just triangles
-        }
-        float[] convHulls = new float[totalVertices];
-
-        convHulls[0] = (float)hullCount;
-        int jj = 1;
-        foreach (ConvexResult cr in _hulls)
-        {
-            // copy vertices for index access
-            float3[] verts = new float3[cr.HullVertices.Count];
-            int kk = 0;
-            foreach (float3 ff in cr.HullVertices)
-            {
-                verts[kk++] = ff;
-            }
-
-            // add to the array one hull's worth of data
-            convHulls[jj++] = cr.HullIndices.Count;
-            convHulls[jj++] = 0f;   // centroid x,y,z
-            convHulls[jj++] = 0f;
-            convHulls[jj++] = 0f;
-            foreach (int ind in cr.HullIndices)
-            {
-                convHulls[jj++] = verts[ind].x;
-                convHulls[jj++] = verts[ind].y;
-                convHulls[jj++] = verts[ind].z;
-            }
-        }
-
-        // create the hull definition in Bullet
-        // m_log.DebugFormat("{0}: CreateGeom: calling CreateHull. lid={1}, key={2}, hulls={3}", LogHeader, _localID, _hullKey, hullCount);
-        BulletSimAPI.CreateHull(_scene.WorldID, _hullKey, hullCount, convHulls);
-        _shapeType = ShapeData.PhysicsShapeType.SHAPE_HULL;
-        // meshes are already scaled by the meshmerizer
-        _scale = new OMV.Vector3(1f, 1f, 1f);
-        DetailLog("{0},BSPrim.CreateGeomHull,done", LocalID);
-        return true;
-    }
-
-    // Callback from convex hull creater with a newly created hull.
-    // Just add it to the collection of hulls for this shape.
-    private void HullReturn(ConvexResult result)
-    {
-        _hulls.Add(result);
-        return;
-    }
-
-    private void VerifyCorrectPhysicalShape()
-    {
-        if (!IsStatic)
-        {
-            // if not static, it will need a hull to efficiently collide with things
-            if (_hullKey == 0)
-            {
-                CreateGeomAndObject(false);
-            }
-
-        }
-    }
-
-    // Create an object in Bullet if it has not already been created
-    // No locking here because this is done when the physics engine is not simulating
-    // Returns 'true' if an object was actually created.
-    private bool CreateObject()
-    {
-        // this routine is called when objects are rebuilt. 
-
-        // the mesh or hull must have already been created in Bullet
-        ShapeData shape;
-        FillShapeInfo(out shape);
-        // m_log.DebugFormat("{0}: CreateObject: lID={1}, shape={2}", LogHeader, _localID, shape.Type);
-        bool ret = BulletSimAPI.CreateObject(_scene.WorldID, shape);
-
-        // the CreateObject() may have recreated the rigid body. Make sure we have the latest address.
-        BSBody = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(_scene.World.Ptr, LocalID));
-        BSShape = new BulletShape(BulletSimAPI.GetCollisionShape2(BSBody.Ptr));
-
-        return ret;
-    }
-
     // Copy prim's info into the BulletSim shape description structure
     public void FillShapeInfo(out ShapeData shape)
     {
-        shape.ID = _localID;
+        shape.ID = LocalID;
         shape.Type = _shapeType;
         shape.Position = _position;
         shape.Rotation = _orientation;
@@ -1380,22 +1095,39 @@ public sealed class BSPrim : BSPhysObject
         shape.Restitution = _restitution;
         shape.Collidable = (!IsPhantom) ? ShapeData.numericTrue : ShapeData.numericFalse;
         shape.Static = _isPhysical ? ShapeData.numericFalse : ShapeData.numericTrue;
+        shape.Solid = IsSolid ? ShapeData.numericFalse : ShapeData.numericTrue;
+        shape.Size = _size;
     }
-
     // Rebuild the geometry and object.
     // This is called when the shape changes so we need to recreate the mesh/hull.
-    // No locking here because this is done when the physics engine is not simulating
+    // Called at taint-time!!!
     private void CreateGeomAndObject(bool forceRebuild)
     {
-        // m_log.DebugFormat("{0}: CreateGeomAndObject. lID={1}, force={2}", LogHeader, _localID, forceRebuild);
-        // Create the geometry that will make up the object
-        if (CreateGeom(forceRebuild))
+        ShapeData shapeData;
+        FillShapeInfo(out shapeData);
+
+        // If this prim is part of a linkset, we must remove and restore the physical
+        //    links of the body is rebuilt.
+        bool needToRestoreLinkset = false;
+
+        // Create the correct physical representation for this type of object.
+        // Updates BSBody and BSShape with the new information.
+        PhysicsScene.Shapes.GetBodyAndShape(forceRebuild, PhysicsScene.World, this, shapeData, _pbs, 
+                        null, delegate(BulletBody dBody)
+        {
+            // Called if the current prim body is about to be destroyed.
+            // Remove all the physical dependencies on the old body.
+            needToRestoreLinkset = Linkset.RemoveBodyDependencies(this);
+        });
+
+        if (needToRestoreLinkset)
         {
-            // Create the object and place it into the world
-            CreateObject();
-            // Make sure the properties are set on the new object
-            UpdatePhysicalParameters();
+            // If physical body dependencies were removed, restore them
+            Linkset.RestoreBodyDependencies(this);
         }
+
+        // Make sure the properties are set on the new object
+        UpdatePhysicalParameters();
         return;
     }
 
@@ -1485,66 +1217,10 @@ public sealed class BSPrim : BSPhysObject
         {
             // For debugging, we can also report the movement of children
             DetailLog("{0},BSPrim.UpdateProperties,child,pos={1},orient={2},vel={3},accel={4},rotVel={5}",
-                    LocalID, entprop.Position, entprop.Rotation, entprop.Velocity, 
+                    LocalID, entprop.Position, entprop.Rotation, entprop.Velocity,
                     entprop.Acceleration, entprop.RotationalVelocity);
         }
              */
     }
-
-    // I've collided with something
-    // Called at taint time from within the Step() function
-    CollisionEventUpdate collisionCollection;
-    public override bool Collide(uint collidingWith, BSPhysObject collidee, OMV.Vector3 contactPoint, OMV.Vector3 contactNormal, float pentrationDepth)
-    {
-        bool ret = false;
-
-        // The following lines make IsColliding() and IsCollidingGround() work
-        _collidingStep = Scene.SimulationStep;
-        if (collidingWith <= Scene.TerrainManager.HighestTerrainID)
-        {
-            _collidingGroundStep = Scene.SimulationStep;
-        }
-
-        // DetailLog("{0},BSPrim.Collison,call,with={1}", LocalID, collidingWith);
-
-        // prims in the same linkset cannot collide with each other
-        if (collidee != null && (this.Linkset.LinksetID == collidee.Linkset.LinksetID))
-        {
-            return ret;
-        }
-
-        // if someone has subscribed for collision events....
-        if (SubscribedEvents()) {
-            // throttle the collisions to the number of milliseconds specified in the subscription
-            int nowTime = Scene.SimulationNowTime;
-            if (nowTime >= _nextCollisionOkTime) {
-                _nextCollisionOkTime = nowTime + _subscribedEventsMs;
-
-                if (collisionCollection == null)
-                    collisionCollection = new CollisionEventUpdate();
-                collisionCollection.AddCollider(collidingWith, new ContactPoint(contactPoint, contactNormal, pentrationDepth));
-                ret = true;
-            }
-        }
-        return ret;
-    }
-
-    // The scene is telling us it's time to pass our collected collisions into the simulator
-    public override void SendCollisions()
-    {
-        if (collisionCollection != null && collisionCollection.Count > 0)
-        {
-            base.SendCollisionUpdate(collisionCollection);
-            // The collisionCollection structure is passed around in the simulator.
-            // Make sure we don't have a handle to that one and that a new one is used next time.
-            collisionCollection = null;
-        }
-    }
-
-    // Invoke the detailed logger and output something if it's enabled.
-    private void DetailLog(string msg, params Object[] args)
-    {
-        Scene.PhysicsLogging.Write(msg, args);
-    }
 }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
index 52997dd..0cf8c91 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
@@ -39,20 +39,20 @@ using log4net;
 using OpenMetaverse;
 
 // TODOs for BulletSim (for BSScene, BSPrim, BSCharacter and BulletSim)
-// Adjust character capsule size when height is adjusted (ScenePresence.SetHeight)
-// Test sculpties
+// Move all logic out of the C++ code and into the C# code for easier future modifications.
+// Test sculpties (verified that they don't work)
 // Compute physics FPS reasonably
 // Based on material, set density and friction
-// More efficient memory usage when passing hull information from BSPrim to BulletSim
-// Move all logic out of the C++ code and into the C# code for easier future modifications.
+// 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 )
-// Use collision masks for collision with terrain and phantom objects 
 // 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
+// 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)
@@ -60,7 +60,7 @@ using OpenMetaverse;
 // Add PID movement operations. What does ScenePresence.MoveToTarget do?
 // Check terrain size. 128 or 127?
 // Raycast
-// 
+//
 namespace OpenSim.Region.Physics.BulletSPlugin
 {
 public class BSScene : PhysicsScene, IPhysicsParameters
@@ -73,12 +73,15 @@ public class BSScene : PhysicsScene, IPhysicsParameters
 
     public string BulletSimVersion = "?";
 
-    public Dictionary<uint, BSPhysObject> PhysObjects = new Dictionary<uint, BSPhysObject>();
+    public Dictionary<uint, BSPhysObject> PhysObjects;
+    public BSShapeCollection Shapes;
 
-    private HashSet<BSPhysObject> m_objectsWithCollisions = new HashSet<BSPhysObject>();
-    // Following is a kludge and can  be removed when avatar animation updating is
-    //    moved to a better place.
-    private HashSet<BSPhysObject> m_avatarsWithCollisions = new HashSet<BSPhysObject>();
+    // Keeping track of the objects with collisions so we can report begin and end of a collision
+    public HashSet<BSPhysObject> ObjectsWithCollisions = new HashSet<BSPhysObject>();
+    public HashSet<BSPhysObject> ObjectsWithNoMoreCollisions = new HashSet<BSPhysObject>();
+    // Keep track of all the avatars so we can send them a collision event
+    //    every tick so OpenSim will update its animation.
+    private HashSet<BSPhysObject> m_avatars = new HashSet<BSPhysObject>();
 
     // List of all the objects that have vehicle properties and should be called
     //    to update each physics step.
@@ -202,6 +205,11 @@ public class BSScene : PhysicsScene, IPhysicsParameters
 
     public override void Initialise(IMesher meshmerizer, IConfigSource config)
     {
+        mesher = meshmerizer;
+        _taintedObjects = new List<TaintCallbackEntry>();
+        PhysObjects = new Dictionary<uint, BSPhysObject>();
+        Shapes = new BSShapeCollection(this);
+
         // Allocate pinned memory to pass parameters.
         m_params = new ConfigurationParameters[1];
         m_paramsHandle = GCHandle.Alloc(m_params, GCHandleType.Pinned);
@@ -215,12 +223,9 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         m_updateArray = new EntityProperties[m_maxUpdatesPerFrame];
         m_updateArrayPinnedHandle = GCHandle.Alloc(m_updateArray, GCHandleType.Pinned);
 
-        mesher = meshmerizer;
-        _taintedObjects = new List<TaintCallbackEntry>();
-
         // Enable very detailed logging.
         // By creating an empty logger when not logging, the log message invocation code
-        // can be left in and every call doesn't have to check for null.
+        //     can be left in and every call doesn't have to check for null.
         if (m_physicsLoggingEnabled)
         {
             PhysicsLogging = new Logging.LogWriter(m_physicsLoggingDir, m_physicsLoggingPrefix, m_physicsLoggingFileMinutes);
@@ -251,7 +256,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         //    a child in a mega-region.
         // Turns out that Bullet really doesn't care about the extents of the simulated
         //    area. It tracks active objects no matter where they are.
-        Vector3 worldExtent = new Vector3(Constants.RegionSize, Constants.RegionSize, 8192f);
+        Vector3 worldExtent = new Vector3(Constants.RegionSize, Constants.RegionSize, Constants.RegionHeight);
 
         // m_log.DebugFormat("{0}: Initialize: Calling BulletSimAPI.Initialize.", LogHeader);
         WorldID = BulletSimAPI.Initialize(worldExtent, m_paramsHandle.AddrOfPinnedObject(),
@@ -322,7 +327,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     {
         m_log.Debug("[BULLETS UNMANAGED]:" + msg);
     }
-    
+  
     // Called directly from unmanaged code so don't do much
     private void BulletLoggerPhysLog(string msg)
     {
@@ -351,6 +356,12 @@ public class BSScene : PhysicsScene, IPhysicsParameters
             Constraints = null;
         }
 
+        if (Shapes != null)
+        {
+            Shapes.Dispose();
+            Shapes = null;
+        }
+
         // Anything left in the unmanaged code should be cleaned out
         BulletSimAPI.Shutdown(WorldID);
 
@@ -379,7 +390,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         // TODO: Remove kludge someday.
         // We must generate a collision for avatars whether they collide or not.
         // This is required by OpenSim to update avatar animations, etc.
-        lock (m_avatarsWithCollisions) m_avatarsWithCollisions.Add(actor);
+        lock (m_avatars) m_avatars.Add(actor);
 
         return actor;
     }
@@ -397,7 +408,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
             {
                 lock (PhysObjects) PhysObjects.Remove(actor.LocalID);
                 // Remove kludge someday
-                lock (m_avatarsWithCollisions) m_avatarsWithCollisions.Remove(bsactor);
+                lock (m_avatars) m_avatars.Remove(bsactor);
             }
             catch (Exception e)
             {
@@ -449,7 +460,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     }
 
     // This is a call from the simulator saying that some physical property has been updated.
-    // The BulletSim driver senses the changing of relevant properties so this taint 
+    // The BulletSim driver senses the changing of relevant properties so this taint
     // information call is not needed.
     public override void AddPhysicsActorTaint(PhysicsActor prim) { }
 
@@ -464,6 +475,9 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         int collidersCount = 0;
         IntPtr collidersPtr;
 
+        int beforeTime = 0;
+        int simTime = 0;
+
         // prevent simulation until we've been initialized
         if (!m_initialized) return 5.0f;
 
@@ -481,16 +495,20 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         int numSubSteps = 0;
         try
         {
+            if (PhysicsLogging.Enabled) beforeTime = Util.EnvironmentTickCount();
+
             numSubSteps = BulletSimAPI.PhysicsStep(WorldID, timeStep, m_maxSubSteps, m_fixedTimeStep,
                         out updatedEntityCount, out updatedEntitiesPtr, out collidersCount, out collidersPtr);
-            DetailLog("{0},Simulate,call, nTaints= {1}, substeps={2}, updates={3}, colliders={4}", 
-                        DetailLogZero, numTaints, numSubSteps, updatedEntityCount, collidersCount); 
+
+            if (PhysicsLogging.Enabled) simTime = Util.EnvironmentTickCountSubtract(beforeTime);
+            DetailLog("{0},Simulate,call, nTaints={1}, simTime={2}, substeps={3}, updates={4}, colliders={5}",
+                        DetailLogZero, numTaints, simTime, numSubSteps, updatedEntityCount, collidersCount);
         }
         catch (Exception e)
         {
-            m_log.WarnFormat("{0},PhysicsStep Exception: nTaints={1}, substeps={2}, updates={3}, colliders={4}, e={5}", 
+            m_log.WarnFormat("{0},PhysicsStep Exception: nTaints={1}, substeps={2}, updates={3}, colliders={4}, e={5}",
                         LogHeader, numTaints, numSubSteps, updatedEntityCount, collidersCount, e);
-            DetailLog("{0},PhysicsStepException,call, nTaints={1}, substeps={2}, updates={3}, colliders={4}", 
+            DetailLog("{0},PhysicsStepException,call, nTaints={1}, substeps={2}, updates={3}, colliders={4}",
                         DetailLogZero, numTaints, numSubSteps, updatedEntityCount, collidersCount);
             updatedEntityCount = 0;
             collidersCount = 0;
@@ -502,12 +520,6 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         // Get a value for 'now' so all the collision and update routines don't have to get their own
         SimulationNowTime = Util.EnvironmentTickCount();
 
-        // This is a kludge to get avatar movement updates. 
-        //   ODE sends collisions for avatars even if there are have been no collisions. This updates
-        //   avatar animations and stuff.
-        // If you fix avatar animation updates, remove this overhead and let normal collision processing happen.
-        m_objectsWithCollisions = new HashSet<BSPhysObject>(m_avatarsWithCollisions);
-
         // If there were collisions, process them by sending the event to the prim.
         // Collisions must be processed before updates.
         if (collidersCount > 0)
@@ -523,11 +535,34 @@ public class BSScene : PhysicsScene, IPhysicsParameters
             }
         }
 
+        // This is a kludge to get avatar movement updates.
+        //   ODE sends collisions for avatars even if there are have been no collisions. This updates
+        //   avatar animations and stuff.
+        // If you fix avatar animation updates, remove this overhead and let normal collision processing happen.
+        foreach (BSPhysObject bsp in m_avatars)
+            bsp.SendCollisions();
+
         // The above SendCollision's batch up the collisions on the objects.
         //      Now push the collisions into the simulator.
-        foreach (BSPhysObject bsp in m_objectsWithCollisions)
-            bsp.SendCollisions();
-        m_objectsWithCollisions.Clear();
+        if (ObjectsWithCollisions.Count > 0)
+        {
+            foreach (BSPhysObject bsp in ObjectsWithCollisions)
+                if (!m_avatars.Contains(bsp))   // don't call avatars twice
+                    if (!bsp.SendCollisions())
+                    {
+                        // If the object is done colliding, see that it's removed from the colliding list
+                        ObjectsWithNoMoreCollisions.Add(bsp);
+                    }
+        }
+
+        // Objects that are done colliding are removed from the ObjectsWithCollisions list.
+        // This can't be done by SendCollisions because it is inside an iteration of ObjectWithCollisions.
+        if (ObjectsWithNoMoreCollisions.Count > 0)
+        {
+            foreach (BSPhysObject po in ObjectsWithNoMoreCollisions)
+                ObjectsWithCollisions.Remove(po);
+            ObjectsWithNoMoreCollisions.Clear();
+        }
 
         // If any of the objects had updated properties, tell the object it has been changed by the physics engine
         if (updatedEntityCount > 0)
@@ -555,7 +590,7 @@ public 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.
         // Since Bullet normally does 5 or 6 substeps, this will normally sum to about 60 FPS.
-        return numSubSteps * m_fixedTimeStep;
+        return numSubSteps * m_fixedTimeStep * 1000;
     }
 
     // Something has collided
@@ -570,20 +605,20 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         if (!PhysObjects.TryGetValue(localID, out collider))
         {
             // If the object that is colliding cannot be found, just ignore the collision.
+            DetailLog("{0},BSScene.SendCollision,colliderNotInObjectList,id={1},with={2}", DetailLogZero, localID, collidingWith);
             return;
         }
 
-        // The terrain is not in the physical object list so 'collidee'
-        //    can be null when Collide() is called.
+        // The terrain is not in the physical object list so 'collidee' can be null when Collide() is called.
         BSPhysObject collidee = null;
         PhysObjects.TryGetValue(collidingWith, out collidee);
 
-        // DetailLog("{0},BSScene.SendCollision,collide,id={1},with={2}", DetailLogZero, localID, collidingWith);
+        DetailLog("{0},BSScene.SendCollision,collide,id={1},with={2}", DetailLogZero, localID, collidingWith);
 
         if (collider.Collide(collidingWith, collidee, collidePoint, collideNormal, penetration))
         {
             // If a collision was posted, remember to send it to the simulator
-            m_objectsWithCollisions.Add(collider);
+            ObjectsWithCollisions.Add(collider);
         }
 
         return;
@@ -599,7 +634,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         TerrainManager.SetTerrain(heightMap);
     }
 
-    public override void SetWaterLevel(float baseheight) 
+    public override void SetWaterLevel(float baseheight)
     {
         m_waterLevel = baseheight;
     }
@@ -609,7 +644,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         return m_waterLevel;
     }
 
-    public override void DeleteTerrain() 
+    public override void DeleteTerrain()
     {
         // m_log.DebugFormat("{0}: DeleteTerrain()", LogHeader);
     }
@@ -771,7 +806,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     //    getters and setters.
     // It is easiest to find an existing definition and copy it.
     // Parameter values are floats. Booleans are converted to a floating value.
-    // 
+    //
     // A ParameterDefn() takes the following parameters:
     //    -- the text name of the parameter. This is used for console input and ini file.
     //    -- a short text description of the parameter. This shows up in the console listing.
@@ -998,7 +1033,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
             (s) => { return s.m_params[0].shouldRandomizeSolverOrder; },
             (s,p,l,v) => { s.m_params[0].shouldRandomizeSolverOrder = v; } ),
             new ParameterDefn("ShouldSplitSimulationIslands", "Enable splitting active object scanning islands",
-            ConfigurationParameters.numericFalse,
+            ConfigurationParameters.numericTrue,
             (s,cf,p,v) => { s.m_params[0].shouldSplitSimulationIslands = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
             (s) => { return s.m_params[0].shouldSplitSimulationIslands; },
             (s,p,l,v) => { s.m_params[0].shouldSplitSimulationIslands = v; } ),
@@ -1193,7 +1228,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
                     }
                 });
                 break;
-            default: 
+            default:
                 // setting only one localID
                 TaintedUpdateParameter(parm, localID, val);
                 break;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
new file mode 100755
index 0000000..dee6243
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
@@ -0,0 +1,735 @@
+/*
+ * 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 OMV = OpenMetaverse;
+using OpenSim.Framework;
+using OpenSim.Region.Physics.Manager;
+using OpenSim.Region.Physics.ConvexDecompositionDotNet;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+public class BSShapeCollection : IDisposable
+{
+    private static string LogHeader = "[BULLETSIM SHAPE COLLECTION]";
+
+    protected BSScene PhysicsScene { get; set; }
+
+    private Object m_collectionActivityLock = new Object();
+
+    // Description of a Mesh
+    private struct MeshDesc
+    {
+        public IntPtr ptr;
+        public int referenceCount;
+        public DateTime lastReferenced;
+    }
+
+    // Description of a hull.
+    // Meshes and hulls have the same shape hash key but we only need hulls for efficient physical objects
+    private struct HullDesc
+    {
+        public IntPtr ptr;
+        public int referenceCount;
+        public DateTime lastReferenced;
+    }
+
+    private struct BodyDesc
+    {
+        public IntPtr ptr;
+        // Bodies are only used once so reference count is always either one or zero
+        public int referenceCount;
+        public DateTime lastReferenced;
+    }
+
+    private Dictionary<ulong, MeshDesc> Meshes = new Dictionary<ulong, MeshDesc>();
+    private Dictionary<ulong, HullDesc> Hulls = new Dictionary<ulong, HullDesc>();
+    private Dictionary<uint, BodyDesc> Bodies = new Dictionary<uint, BodyDesc>();
+
+    public BSShapeCollection(BSScene physScene)
+    {
+        PhysicsScene = physScene;
+    }
+
+    public void Dispose()
+    {
+        // TODO!!!!!!!!!
+    }
+
+    // Callbacks called just before either the body or shape is destroyed.
+    // Mostly used for changing bodies out from under Linksets.
+    // Useful for other cases where parameters need saving.
+    // Passing 'null' says no callback.
+    public delegate void ShapeDestructionCallback(BulletShape shape);
+    public delegate void BodyDestructionCallback(BulletBody body);
+
+    // Called to update/change the body and shape for an object.
+    // First checks the shape and updates that if necessary then makes
+    //    sure the body is of the right type.
+    // Return 'true' if either the body or the shape changed.
+    // Called at taint-time!!
+    public bool GetBodyAndShape(bool forceRebuild, BulletSim sim, BSPrim prim, 
+                    ShapeData shapeData, PrimitiveBaseShape pbs,
+                    ShapeDestructionCallback shapeCallback, BodyDestructionCallback bodyCallback)
+    {
+        bool ret = false;
+
+        // This lock could probably be pushed down lower but building shouldn't take long
+        lock (m_collectionActivityLock)
+        {
+            // Do we have the correct geometry for this type of object?
+            // Updates prim.BSShape with information/pointers to requested shape
+            bool newGeom = CreateGeom(forceRebuild, prim, shapeData, pbs, shapeCallback);
+            // If we had to select a new shape geometry for the object,
+            //    rebuild the body around it.
+            // Updates prim.BSBody with information/pointers to requested body
+            bool newBody = CreateBody((newGeom || forceRebuild), prim, PhysicsScene.World, prim.BSShape, shapeData, bodyCallback);
+            ret = newGeom || newBody;
+        }
+        DetailLog("{0},BSShapeCollection.GetBodyAndShape,force={1},ret={2},body={3},shape={4}",
+                                prim.LocalID, forceRebuild, ret, prim.BSBody, prim.BSShape);
+
+        return ret;
+    }
+
+    // Track another user of a body
+    // We presume the caller has allocated the body.
+    // Bodies only have one user so the reference count is either 1 or 0.
+    public void ReferenceBody(BulletBody body, bool atTaintTime)
+    {
+        lock (m_collectionActivityLock)
+        {
+            BodyDesc bodyDesc;
+            if (Bodies.TryGetValue(body.ID, out bodyDesc))
+            {
+                bodyDesc.referenceCount++;
+                DetailLog("{0},BSShapeCollection.ReferenceBody,existingBody,body={1},ref={2}", body.ID, body, bodyDesc.referenceCount);
+            }
+            else
+            {
+                // New entry
+                bodyDesc.ptr = body.ptr;
+                bodyDesc.referenceCount = 1;
+                DetailLog("{0},BSShapeCollection.ReferenceBody,newBody,ref={1}", body.ID, body, bodyDesc.referenceCount);
+            }
+            bodyDesc.lastReferenced = System.DateTime.Now;
+            Bodies[body.ID] = bodyDesc;
+        }
+}
+
+    // Release the usage of a body.
+    // Called when releasing use of a BSBody. BSShape is handled separately.
+    public void DereferenceBody(BulletBody body, bool inTaintTime, BodyDestructionCallback bodyCallback )
+    {
+        if (body.ptr == IntPtr.Zero)
+            return;
+
+        lock (m_collectionActivityLock)
+        {
+            BodyDesc bodyDesc;
+            if (Bodies.TryGetValue(body.ID, out bodyDesc))
+            {
+                bodyDesc.referenceCount--;
+                bodyDesc.lastReferenced = System.DateTime.Now;
+                Bodies[body.ID] = bodyDesc;
+                DetailLog("{0},BSShapeCollection.DereferenceBody,ref={1}", body.ID, bodyDesc.referenceCount);
+
+                // If body is no longer being used, free it -- bodies are never shared.
+                if (bodyDesc.referenceCount == 0)
+                {
+                    Bodies.Remove(body.ID);
+                    BSScene.TaintCallback removeOperation = delegate()
+                    {
+                        DetailLog("{0},BSShapeCollection.DereferenceBody,DestroyingBody. ptr={1}",
+                                                    body.ID, body.ptr.ToString("X"));
+                        // If the caller needs to know, pass the event up.
+                        if (bodyCallback != null) bodyCallback(body);
+
+                        // Zero any reference to the shape so it is not freed when the body is deleted.
+                        BulletSimAPI.SetCollisionShape2(PhysicsScene.World.ptr, body.ptr, IntPtr.Zero);
+                        // It may have already been removed from the world in which case the next is a NOOP.
+                        BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, body.ptr);
+                        BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, body.ptr);
+                    };
+                    // If already in taint-time, do the operations now. Otherwise queue for later.
+                    if (inTaintTime)
+                        removeOperation();
+                    else
+                        PhysicsScene.TaintedObject("BSShapeCollection.DereferenceBody", removeOperation);
+                }
+            }
+            else
+            {
+                DetailLog("{0},BSShapeCollection.DereferenceBody,DID NOT FIND BODY", body.ID, bodyDesc.referenceCount);
+            }
+        }
+    }
+
+    // Track the datastructures and use count for a shape.
+    // When creating a hull, this is called first to reference the mesh
+    //     and then again to reference the hull.
+    // Meshes and hulls for the same shape have the same hash key.
+    // NOTE that native shapes are not added to the mesh list or removed.
+    // Returns 'true' if this is the initial reference to the shape. Otherwise reused.
+    private bool ReferenceShape(BulletShape shape)
+    {
+        bool ret = false;
+        switch (shape.type)
+        {
+            case ShapeData.PhysicsShapeType.SHAPE_MESH:
+                MeshDesc meshDesc;
+                if (Meshes.TryGetValue(shape.shapeKey, out meshDesc))
+                {
+                    // There is an existing instance of this mesh.
+                    meshDesc.referenceCount++;
+                    DetailLog("{0},BSShapeColliction.ReferenceShape,existingMesh,key={1},cnt={2}",
+                                BSScene.DetailLogZero, shape.shapeKey.ToString("X"), meshDesc.referenceCount);
+                }
+                else
+                {
+                    // This is a new reference to a mesh
+                    meshDesc.ptr = shape.ptr;
+                    // We keep a reference to the underlying IMesh data so a hull can be built
+                    meshDesc.referenceCount = 1;
+                    DetailLog("{0},BSShapeColliction.ReferenceShape,newMesh,key={1},cnt={2}",
+                                BSScene.DetailLogZero, shape.shapeKey.ToString("X"), meshDesc.referenceCount);
+                    ret = true;
+                }
+                meshDesc.lastReferenced = System.DateTime.Now;
+                Meshes[shape.shapeKey] = meshDesc;
+                break;
+            case ShapeData.PhysicsShapeType.SHAPE_HULL:
+                HullDesc hullDesc;
+                if (Hulls.TryGetValue(shape.shapeKey, out hullDesc))
+                {
+                    // There is an existing instance of this hull.
+                    hullDesc.referenceCount++;
+                    DetailLog("{0},BSShapeColliction.ReferenceShape,existingHull,key={1},cnt={2}",
+                                BSScene.DetailLogZero, shape.shapeKey.ToString("X"), hullDesc.referenceCount);
+                }
+                else
+                {
+                    // This is a new reference to a hull
+                    hullDesc.ptr = shape.ptr;
+                    hullDesc.referenceCount = 1;
+                    DetailLog("{0},BSShapeColliction.ReferenceShape,newHull,key={1},cnt={2}",
+                                BSScene.DetailLogZero, shape.shapeKey.ToString("X"), hullDesc.referenceCount);
+                    ret = true;
+
+                }
+                hullDesc.lastReferenced = System.DateTime.Now;
+                Hulls[shape.shapeKey] = hullDesc;
+                break;
+            case ShapeData.PhysicsShapeType.SHAPE_UNKNOWN:
+                break;
+            default:
+                // Native shapes are not tracked and they don't go into any list
+                break;
+        }
+        return ret;
+    }
+
+    // Release the usage of a shape.
+    // The collisionObject is released since it is a copy of the real collision shape.
+    public void DereferenceShape(BulletShape shape, bool atTaintTime, ShapeDestructionCallback shapeCallback)
+    {
+        if (shape.ptr == IntPtr.Zero)
+            return;
+
+        BSScene.TaintCallback dereferenceOperation = delegate()
+        {
+            switch (shape.type)
+            {
+                case ShapeData.PhysicsShapeType.SHAPE_HULL:
+                    DereferenceHull(shape, shapeCallback);
+                    break;
+                case ShapeData.PhysicsShapeType.SHAPE_MESH:
+                    DereferenceMesh(shape, shapeCallback);
+                    break;
+                case ShapeData.PhysicsShapeType.SHAPE_UNKNOWN:
+                    break;
+                default:
+                    // Native shapes are not tracked and are released immediately
+                    if (shape.ptr != IntPtr.Zero & shape.isNativeShape)
+                    {
+                        DetailLog("{0},BSShapeCollection.DereferenceShape,deleteNativeShape,ptr={1},taintTime={2}",
+                                        BSScene.DetailLogZero, shape.ptr.ToString("X"), atTaintTime);
+                        if (shapeCallback != null) shapeCallback(shape);
+                        BulletSimAPI.DeleteCollisionShape2(PhysicsScene.World.ptr, shape.ptr);
+                    }
+                    break;
+            }
+        };
+        if (atTaintTime)
+        {
+            lock (m_collectionActivityLock)
+            {
+                dereferenceOperation();
+            }
+        }
+        else
+        {
+            PhysicsScene.TaintedObject("BSShapeCollection.DereferenceShape", dereferenceOperation);
+        }
+    }
+
+    // Count down the reference count for a mesh shape
+    // Called at taint-time.
+    private void DereferenceMesh(BulletShape shape, ShapeDestructionCallback shapeCallback)
+    {
+        MeshDesc meshDesc;
+        if (Meshes.TryGetValue(shape.shapeKey, out meshDesc))
+        {
+            meshDesc.referenceCount--;
+            // TODO: release the Bullet storage
+            if (shapeCallback != null) shapeCallback(shape);
+            meshDesc.lastReferenced = System.DateTime.Now;
+            Meshes[shape.shapeKey] = meshDesc;
+            DetailLog("{0},BSShapeCollection.DereferenceMesh,key={1},refCnt={2}",
+                    BSScene.DetailLogZero, shape.shapeKey.ToString("X"), meshDesc.referenceCount);
+
+        }
+    }
+
+    // Count down the reference count for a hull shape
+    // Called at taint-time.
+    private void DereferenceHull(BulletShape shape, ShapeDestructionCallback shapeCallback)
+    {
+        HullDesc hullDesc;
+        if (Hulls.TryGetValue(shape.shapeKey, out hullDesc))
+        {
+            hullDesc.referenceCount--;
+            // TODO: release the Bullet storage (aging old entries?)
+            if (shapeCallback != null) shapeCallback(shape);
+            hullDesc.lastReferenced = System.DateTime.Now;
+            Hulls[shape.shapeKey] = hullDesc;
+            DetailLog("{0},BSShapeCollection.DereferenceHull,key={1},refCnt={2}",
+                    BSScene.DetailLogZero, shape.shapeKey.ToString("X"), hullDesc.referenceCount);
+        }
+    }
+
+    // Create the geometry information in Bullet for later use.
+    // The objects needs a hull if it's physical otherwise a mesh is enough.
+    // No locking here because this is done when we know physics is not simulating.
+    // if 'forceRebuild' is true, the geometry is rebuilt. Otherwise a previously built version is used.
+    // Returns 'true' if the geometry was rebuilt.
+    // Called at taint-time!
+    private bool CreateGeom(bool forceRebuild, BSPrim prim, ShapeData shapeData, 
+                            PrimitiveBaseShape pbs, ShapeDestructionCallback shapeCallback)
+    {
+        bool ret = false;
+        bool haveShape = false;
+        bool nativeShapePossible = true;
+
+        // If the prim attributes are simple, this could be a simple Bullet native shape
+        if (nativeShapePossible
+                && ((pbs.SculptEntry && !PhysicsScene.ShouldMeshSculptedPrim)
+                    || (pbs.ProfileBegin == 0 && pbs.ProfileEnd == 0
+                        && pbs.ProfileHollow == 0
+                        && pbs.PathTwist == 0 && pbs.PathTwistBegin == 0
+                        && pbs.PathBegin == 0 && pbs.PathEnd == 0
+                        && pbs.PathTaperX == 0 && pbs.PathTaperY == 0
+                        && pbs.PathScaleX == 100 && pbs.PathScaleY == 100
+                        && pbs.PathShearX == 0 && pbs.PathShearY == 0) ) )
+        {
+            if (pbs.ProfileShape == ProfileShape.HalfCircle && pbs.PathCurve == (byte)Extrusion.Curve1)
+            {
+                haveShape = true;
+                if (forceRebuild
+                        || prim.Scale != shapeData.Size
+                        || prim.BSShape.type != ShapeData.PhysicsShapeType.SHAPE_SPHERE
+                        )
+                {
+                    ret = GetReferenceToNativeShape(prim, shapeData, ShapeData.PhysicsShapeType.SHAPE_SPHERE, 
+                                            ShapeData.FixedShapeKey.KEY_SPHERE, shapeCallback);
+                    DetailLog("{0},BSShapeCollection.CreateGeom,sphere,force={1},shape={2}",
+                                        prim.LocalID, forceRebuild, prim.BSShape);
+                }
+            }
+            else
+            {
+                haveShape = true;
+                if (forceRebuild
+                        || prim.Scale != shapeData.Size
+                        || prim.BSShape.type != ShapeData.PhysicsShapeType.SHAPE_BOX
+                        )
+                {
+                    ret = GetReferenceToNativeShape( prim, shapeData, ShapeData.PhysicsShapeType.SHAPE_BOX, 
+                                            ShapeData.FixedShapeKey.KEY_BOX, shapeCallback);
+                    DetailLog("{0},BSShapeCollection.CreateGeom,box,force={1},shape={2}",
+                                        prim.LocalID, forceRebuild, prim.BSShape);
+                }
+            }
+        }
+        // If a simple shape is not happening, create a mesh and possibly a hull.
+        // Note that if it's a native shape, the check for physical/non-physical is not
+        //     made. Native shapes are best used in either case.
+        if (!haveShape)
+        {
+            if (prim.IsPhysical)
+            {
+                // Update prim.BSShape to reference a hull of this shape.
+                ret = GetReferenceToHull(prim, shapeData, pbs, shapeCallback);
+                DetailLog("{0},BSShapeCollection.CreateGeom,hull,shape={1},key={2}",
+                                        shapeData.ID, prim.BSShape, prim.BSShape.shapeKey.ToString("X"));
+            }
+            else
+            {
+                ret = GetReferenceToMesh(prim, shapeData, pbs, shapeCallback);
+                DetailLog("{0},BSShapeCollection.CreateGeom,mesh,shape={1},key={2}",
+                                        shapeData.ID, prim.BSShape, prim.BSShape.shapeKey.ToString("X"));
+            }
+        }
+        return ret;
+    }
+
+    // Creates a native shape and assignes it to prim.BSShape
+    private bool GetReferenceToNativeShape( BSPrim prim, ShapeData shapeData,
+                            ShapeData.PhysicsShapeType shapeType, ShapeData.FixedShapeKey shapeKey,
+                            ShapeDestructionCallback shapeCallback)
+    {
+        BulletShape newShape;
+
+        shapeData.Type = shapeType;
+        // Bullet native objects are scaled by the Bullet engine so pass the size in
+        prim.Scale = shapeData.Size;
+        shapeData.Scale = shapeData.Size;
+
+        // release any previous shape
+        DereferenceShape(prim.BSShape, true, shapeCallback);
+
+        // Native shapes are always built independently.
+        newShape = new BulletShape(BulletSimAPI.BuildNativeShape2(PhysicsScene.World.ptr, shapeData), shapeType);
+        newShape.shapeKey = (ulong)shapeKey;
+        newShape.isNativeShape = true;
+
+        // Don't need to do a 'ReferenceShape()' here because native shapes are not tracked.
+        // DetailLog("{0},BSShapeCollection.AddNativeShapeToPrim,create,newshape={1}", shapeData.ID, newShape);
+
+        prim.BSShape = newShape;
+        return true;
+    }
+
+    // Builds a mesh shape in the physical world and updates prim.BSShape.
+    // Dereferences previous shape in BSShape and adds a reference for this new shape.
+    // Returns 'true' of a mesh was actually built. Otherwise .
+    // Called at taint-time!
+    private bool GetReferenceToMesh(BSPrim prim, ShapeData shapeData, PrimitiveBaseShape pbs,
+                                ShapeDestructionCallback shapeCallback)
+    {
+        BulletShape newShape = new BulletShape(IntPtr.Zero);
+
+        float lod;
+        ulong newMeshKey = ComputeShapeKey(shapeData, pbs, out lod);
+
+        // if this new shape is the same as last time, don't recreate the mesh
+        if (prim.BSShape.shapeKey == newMeshKey) return false;
+
+        DetailLog("{0},BSShapeCollection.CreateGeomMesh,create,oldKey={1},newKey={2}",
+                                prim.LocalID, prim.BSShape.shapeKey.ToString("X"), newMeshKey.ToString("X"));
+
+        // Since we're recreating new, get rid of the reference to the previous shape
+        DereferenceShape(prim.BSShape, true, shapeCallback);
+
+        newShape = CreatePhysicalMesh(prim.PhysObjectName, newMeshKey, pbs, shapeData.Size, lod);
+
+        ReferenceShape(newShape);
+
+        // meshes are already scaled by the meshmerizer
+        prim.Scale = new OMV.Vector3(1f, 1f, 1f);
+        prim.BSShape = newShape;
+
+        return true;        // 'true' means a new shape has been added to this prim
+    }
+
+    private BulletShape CreatePhysicalMesh(string objName, ulong newMeshKey, PrimitiveBaseShape pbs, OMV.Vector3 size, float lod)
+    {
+        IMesh meshData = null;
+        IntPtr meshPtr;
+        MeshDesc meshDesc;
+        if (Meshes.TryGetValue(newMeshKey, out meshDesc))
+        {
+            // If the mesh has already been built just use it.
+            meshPtr = meshDesc.ptr;
+        }
+        else
+        {
+            // Pass false for physicalness as this creates some sort of bounding box which we don't need
+            meshData = PhysicsScene.mesher.CreateMesh(objName, pbs, size, lod, false);
+
+            int[] indices = meshData.getIndexListAsInt();
+            List<OMV.Vector3> vertices = meshData.getVertexList();
+
+            float[] verticesAsFloats = new float[vertices.Count * 3];
+            int vi = 0;
+            foreach (OMV.Vector3 vv in vertices)
+            {
+                verticesAsFloats[vi++] = vv.X;
+                verticesAsFloats[vi++] = vv.Y;
+                verticesAsFloats[vi++] = vv.Z;
+            }
+
+            // m_log.DebugFormat("{0}: CreateGeomMesh: calling CreateMesh. lid={1}, key={2}, indices={3}, vertices={4}",
+            //                  LogHeader, prim.LocalID, newMeshKey, indices.Length, vertices.Count);
+
+            meshPtr = BulletSimAPI.CreateMeshShape2(PhysicsScene.World.ptr,
+                                indices.GetLength(0), indices, vertices.Count, verticesAsFloats);
+        }
+        BulletShape newShape = new BulletShape(meshPtr, ShapeData.PhysicsShapeType.SHAPE_MESH);
+        newShape.shapeKey = newMeshKey;
+
+        return newShape;
+    }
+
+    // See that hull shape exists in the physical world and update prim.BSShape.
+    // We could be creating the hull because scale changed or whatever.
+    private bool GetReferenceToHull(BSPrim prim, ShapeData shapeData, PrimitiveBaseShape pbs,
+                                ShapeDestructionCallback shapeCallback)
+    {
+        BulletShape newShape;
+
+        float lod;
+        ulong newHullKey = ComputeShapeKey(shapeData, pbs, out lod);
+
+        // if the hull hasn't changed, don't rebuild it
+        if (newHullKey == prim.BSShape.shapeKey && prim.BSShape.type == ShapeData.PhysicsShapeType.SHAPE_HULL)
+            return false;
+
+        DetailLog("{0},BSShapeCollection.CreateGeomHull,create,oldKey={1},newKey={2}",
+                        prim.LocalID, prim.BSShape.shapeKey.ToString("X"), newHullKey.ToString("X"));
+
+        // Remove usage of the previous shape. Also removes reference to underlying mesh if it is a hull.
+        DereferenceShape(prim.BSShape, true, shapeCallback);
+
+        newShape = CreatePhysicalHull(prim.PhysObjectName, newHullKey, pbs, shapeData.Size, lod);
+
+        ReferenceShape(newShape);
+
+        // hulls are already scaled by the meshmerizer
+        prim.Scale = new OMV.Vector3(1f, 1f, 1f);
+        prim.BSShape = newShape;
+        return true;        // 'true' means a new shape has been added to this prim
+    }
+
+    List<ConvexResult> m_hulls;
+    private BulletShape CreatePhysicalHull(string objName, ulong newHullKey, PrimitiveBaseShape pbs, OMV.Vector3 size, float lod)
+    {
+
+        IntPtr hullPtr;
+        HullDesc hullDesc;
+        if (Hulls.TryGetValue(newHullKey, out hullDesc))
+        {
+            // If the hull shape already is created, just use it.
+            hullPtr = hullDesc.ptr;
+        }
+        else
+        {
+            // Build a new hull in the physical world
+            // Pass false for physicalness as this creates some sort of bounding box which we don't need
+            IMesh meshData = PhysicsScene.mesher.CreateMesh(objName, pbs, size, lod, false);
+
+            int[] indices = meshData.getIndexListAsInt();
+            List<OMV.Vector3> vertices = meshData.getVertexList();
+
+            //format conversion from IMesh format to DecompDesc format
+            List<int> convIndices = new List<int>();
+            List<float3> convVertices = new List<float3>();
+            for (int ii = 0; ii < indices.GetLength(0); ii++)
+            {
+                convIndices.Add(indices[ii]);
+            }
+            foreach (OMV.Vector3 vv in vertices)
+            {
+                convVertices.Add(new float3(vv.X, vv.Y, vv.Z));
+            }
+
+            // setup and do convex hull conversion
+            m_hulls = new List<ConvexResult>();
+            DecompDesc dcomp = new DecompDesc();
+            dcomp.mIndices = convIndices;
+            dcomp.mVertices = convVertices;
+            ConvexBuilder convexBuilder = new ConvexBuilder(HullReturn);
+            // create the hull into the _hulls variable
+            convexBuilder.process(dcomp);
+
+            // Convert the vertices and indices for passing to unmanaged.
+            // The hull information is passed as a large floating point array.
+            // The format is:
+            //  convHulls[0] = number of hulls
+            //  convHulls[1] = number of vertices in first hull
+            //  convHulls[2] = hull centroid X coordinate
+            //  convHulls[3] = hull centroid Y coordinate
+            //  convHulls[4] = hull centroid Z coordinate
+            //  convHulls[5] = first hull vertex X
+            //  convHulls[6] = first hull vertex Y
+            //  convHulls[7] = first hull vertex Z
+            //  convHulls[8] = second hull vertex X
+            //  ...
+            //  convHulls[n] = number of vertices in second hull
+            //  convHulls[n+1] = second hull centroid X coordinate
+            //  ...
+            //
+            // TODO: is is very inefficient. Someday change the convex hull generator to return
+            //   data structures that do not need to be converted in order to pass to Bullet.
+            //   And maybe put the values directly into pinned memory rather than marshaling.
+            int hullCount = m_hulls.Count;
+            int totalVertices = 1;          // include one for the count of the hulls
+            foreach (ConvexResult cr in m_hulls)
+            {
+                totalVertices += 4;                         // add four for the vertex count and centroid
+                totalVertices += cr.HullIndices.Count * 3;  // we pass just triangles
+            }
+            float[] convHulls = new float[totalVertices];
+
+            convHulls[0] = (float)hullCount;
+            int jj = 1;
+            foreach (ConvexResult cr in m_hulls)
+            {
+                // copy vertices for index access
+                float3[] verts = new float3[cr.HullVertices.Count];
+                int kk = 0;
+                foreach (float3 ff in cr.HullVertices)
+                {
+                    verts[kk++] = ff;
+                }
+
+                // add to the array one hull's worth of data
+                convHulls[jj++] = cr.HullIndices.Count;
+                convHulls[jj++] = 0f;   // centroid x,y,z
+                convHulls[jj++] = 0f;
+                convHulls[jj++] = 0f;
+                foreach (int ind in cr.HullIndices)
+                {
+                    convHulls[jj++] = verts[ind].x;
+                    convHulls[jj++] = verts[ind].y;
+                    convHulls[jj++] = verts[ind].z;
+                }
+            }
+            // create the hull data structure in Bullet
+            hullPtr = BulletSimAPI.CreateHullShape2(PhysicsScene.World.ptr, hullCount, convHulls);
+        }
+
+        BulletShape newShape = new BulletShape(hullPtr, ShapeData.PhysicsShapeType.SHAPE_HULL);
+        newShape.shapeKey = newHullKey;
+
+        return newShape;        // 'true' means a new shape has been added to this prim
+    }
+
+    // Callback from convex hull creater with a newly created hull.
+    // Just add it to our collection of hulls for this shape.
+    private void HullReturn(ConvexResult result)
+    {
+        m_hulls.Add(result);
+        return;
+    }
+
+    // Create a hash of all the shape parameters to be used as a key
+    //    for this particular shape.
+    private ulong ComputeShapeKey(ShapeData shapeData, PrimitiveBaseShape pbs, out float retLod)
+    {
+        // level of detail based on size and type of the object
+        float lod = PhysicsScene.MeshLOD;
+        if (pbs.SculptEntry)
+            lod = PhysicsScene.SculptLOD;
+
+        float maxAxis = Math.Max(shapeData.Size.X, Math.Max(shapeData.Size.Y, shapeData.Size.Z));
+        if (maxAxis > PhysicsScene.MeshMegaPrimThreshold)
+            lod = PhysicsScene.MeshMegaPrimLOD;
+
+        retLod = lod;
+        return (ulong)pbs.GetMeshKey(shapeData.Size, lod);
+    }
+    // For those who don't want the LOD
+    private ulong ComputeShapeKey(ShapeData shapeData, PrimitiveBaseShape pbs)
+    {
+        float lod;
+        return ComputeShapeKey(shapeData, pbs, out lod);
+    }
+
+    // Create a body object in Bullet.
+    // Updates prim.BSBody with the information about the new body if one is created.
+    // Returns 'true' if an object was actually created.
+    // Called at taint-time.
+    private bool CreateBody(bool forceRebuild, BSPrim prim, BulletSim sim, BulletShape shape, 
+                            ShapeData shapeData, BodyDestructionCallback bodyCallback)
+    {
+        bool ret = false;
+
+        // the mesh, hull or native shape must have already been created in Bullet
+        bool mustRebuild = (prim.BSBody.ptr == IntPtr.Zero);
+
+        // If there is an existing body, verify it's of an acceptable type.
+        // If not a solid object, body is a GhostObject. Otherwise a RigidBody.
+        if (!mustRebuild)
+        {
+            CollisionObjectTypes bodyType = (CollisionObjectTypes)BulletSimAPI.GetBodyType2(prim.BSBody.ptr);
+            if (prim.IsSolid && bodyType != CollisionObjectTypes.CO_RIGID_BODY
+                || !prim.IsSolid && bodyType != CollisionObjectTypes.CO_GHOST_OBJECT)
+            {
+                // If the collisionObject is not the correct type for solidness, rebuild what's there
+                mustRebuild = true;
+            }
+
+        }
+
+        if (mustRebuild || forceRebuild)
+        {
+            DereferenceBody(prim.BSBody, true, bodyCallback);
+
+            BulletBody aBody;
+            IntPtr bodyPtr = IntPtr.Zero;
+            if (prim.IsSolid)
+            {
+                bodyPtr = BulletSimAPI.CreateBodyFromShape2(sim.ptr, shape.ptr,
+                                        shapeData.ID, shapeData.Position, shapeData.Rotation);
+                // DetailLog("{0},BSShapeCollection.CreateBody,mesh,ptr={1}", prim.LocalID, bodyPtr.ToString("X"));
+            }
+            else
+            {
+                bodyPtr = BulletSimAPI.CreateGhostFromShape2(sim.ptr, shape.ptr,
+                                        shapeData.ID, shapeData.Position, shapeData.Rotation);
+                // DetailLog("{0},BSShapeCollection.CreateBody,ghost,ptr={1}", prim.LocalID, bodyPtr.ToString("X"));
+            }
+            aBody = new BulletBody(shapeData.ID, bodyPtr);
+
+            ReferenceBody(aBody, true);
+
+            prim.BSBody = aBody;
+
+            ret = true;
+        }
+
+        return ret;
+    }
+
+    private void DetailLog(string msg, params Object[] args)
+    {
+        PhysicsScene.PhysicsLogging.Write(msg, args);
+    }
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
index d48462e..70aa429 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
@@ -57,14 +57,14 @@ public class BSTerrainManager
     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, 0f);
+    public Vector3 DefaultRegionSize = new Vector3(Constants.RegionSize, Constants.RegionSize, Constants.RegionHeight);
 
     // The scene that I am part of
-    private BSScene m_physicsScene;
+    private BSScene PhysicsScene { get; set; }
 
     // The ground plane created to keep thing from falling to infinity.
     private BulletBody m_groundPlane;
-    
+
     // If doing mega-regions, if we're region zero we will be managing multiple
     //    region terrains since region zero does the physics for the whole mega-region.
     private Dictionary<Vector2, BulletHeightMapInfo> m_heightMaps;
@@ -84,18 +84,18 @@ public class BSTerrainManager
     // If the parent region (region 0), this is the extent of the combined regions
     //     relative to the origin of region zero
     private Vector3 m_worldMax;
-    private PhysicsScene m_parentScene;
+    private PhysicsScene MegaRegionParentPhysicsScene { get; set; }
 
     public BSTerrainManager(BSScene physicsScene)
     {
-        m_physicsScene = physicsScene;
+        PhysicsScene = physicsScene;
         m_heightMaps = new Dictionary<Vector2,BulletHeightMapInfo>();
         m_terrainModified = false;
 
         // Assume one region of default size
         m_worldOffset = Vector3.Zero;
-        m_worldMax = new Vector3(DefaultRegionSize.X, DefaultRegionSize.Y, 4096f);
-        m_parentScene = null;
+        m_worldMax = new Vector3(DefaultRegionSize);
+        MegaRegionParentPhysicsScene = null;
     }
 
     // Create the initial instance of terrain and the underlying ground plane.
@@ -107,10 +107,16 @@ public class BSTerrainManager
     public void CreateInitialGroundPlaneAndTerrain()
     {
         // 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));
-        m_groundPlane = new BulletBody(BSScene.GROUNDPLANE_ID, 
-                        BulletSimAPI.CreateBodyWithDefaultMotionState2(groundPlaneShape.Ptr, Vector3.Zero, Quaternion.Identity));
-        BulletSimAPI.AddObjectToWorld2(m_physicsScene.World.Ptr, m_groundPlane.Ptr);
+        BulletShape groundPlaneShape = new BulletShape(
+                    BulletSimAPI.CreateGroundPlaneShape2(BSScene.GROUNDPLANE_ID, 1f, TERRAIN_COLLISION_MARGIN),
+                    ShapeData.PhysicsShapeType.SHAPE_GROUNDPLANE);
+        m_groundPlane = new BulletBody(BSScene.GROUNDPLANE_ID,
+                        BulletSimAPI.CreateBodyWithDefaultMotionState2(groundPlaneShape.ptr, BSScene.GROUNDPLANE_ID,
+                                                            Vector3.Zero, Quaternion.Identity));
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_groundPlane.ptr);
+        // Everything collides with the ground plane.
+        BulletSimAPI.SetCollisionFilterMask2(m_groundPlane.ptr,
+                        (uint)CollisionFilterGroups.GroundPlaneFilter, (uint)CollisionFilterGroups.GroundPlaneMask);
 
         Vector3 minTerrainCoords = new Vector3(0f, 0f, HEIGHT_INITIALIZATION - HEIGHT_EQUAL_FUDGE);
         Vector3 maxTerrainCoords = new Vector3(DefaultRegionSize.X, DefaultRegionSize.Y, HEIGHT_INITIALIZATION);
@@ -126,13 +132,13 @@ public class BSTerrainManager
     // Release all the terrain structures we might have allocated
     public void ReleaseGroundPlaneAndTerrain()
     {
-        if (m_groundPlane.Ptr != IntPtr.Zero)
+        if (m_groundPlane.ptr != IntPtr.Zero)
         {
-            if (BulletSimAPI.RemoveObjectFromWorld2(m_physicsScene.World.Ptr, m_groundPlane.Ptr))
+            if (BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_groundPlane.ptr))
             {
-                BulletSimAPI.DestroyObject2(m_physicsScene.World.Ptr, m_groundPlane.Ptr);
+                BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_groundPlane.ptr);
             }
-            m_groundPlane.Ptr = IntPtr.Zero;
+            m_groundPlane.ptr = IntPtr.Zero;
         }
 
         ReleaseTerrain();
@@ -143,9 +149,9 @@ public class BSTerrainManager
     {
         foreach (KeyValuePair<Vector2, BulletHeightMapInfo> kvp in m_heightMaps)
         {
-            if (BulletSimAPI.RemoveObjectFromWorld2(m_physicsScene.World.Ptr, kvp.Value.terrainBody.Ptr))
+            if (BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, kvp.Value.terrainBody.ptr))
             {
-                BulletSimAPI.DestroyObject2(m_physicsScene.World.Ptr, kvp.Value.terrainBody.Ptr);
+                BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, kvp.Value.terrainBody.ptr);
                 BulletSimAPI.ReleaseHeightMapInfo2(kvp.Value.Ptr);
             }
         }
@@ -155,19 +161,19 @@ public class BSTerrainManager
     // The simulator wants to set a new heightmap for the terrain.
     public void SetTerrain(float[] heightMap) {
         float[] localHeightMap = heightMap;
-        m_physicsScene.TaintedObject("TerrainManager.SetTerrain", delegate()
+        PhysicsScene.TaintedObject("TerrainManager.SetTerrain", delegate()
         {
-            if (m_worldOffset != Vector3.Zero && m_parentScene != null)
+            if (m_worldOffset != Vector3.Zero && MegaRegionParentPhysicsScene != null)
             {
                 // If a child of a mega-region, we shouldn't have any terrain allocated for us
                 ReleaseGroundPlaneAndTerrain();
                 // If doing the mega-prim stuff and we are the child of the zero region,
                 //    the terrain is added to our parent
-                if (m_parentScene is BSScene)
+                if (MegaRegionParentPhysicsScene is BSScene)
                 {
                     DetailLog("{0},SetTerrain.ToParent,offset={1},worldMax={2}",
                                     BSScene.DetailLogZero, m_worldOffset, m_worldMax);
-                    ((BSScene)m_parentScene).TerrainManager.UpdateOrCreateTerrain(BSScene.CHILDTERRAIN_ID,
+                    ((BSScene)MegaRegionParentPhysicsScene).TerrainManager.UpdateOrCreateTerrain(BSScene.CHILDTERRAIN_ID,
                                     localHeightMap, m_worldOffset, m_worldOffset + DefaultRegionSize, true);
                 }
             }
@@ -176,7 +182,8 @@ public class BSTerrainManager
                 // If not doing the mega-prim thing, just change the terrain
                 DetailLog("{0},SetTerrain.Existing", BSScene.DetailLogZero);
 
-                UpdateOrCreateTerrain(BSScene.TERRAIN_ID, localHeightMap, m_worldOffset, m_worldOffset + DefaultRegionSize, true);
+                UpdateOrCreateTerrain(BSScene.TERRAIN_ID, localHeightMap,
+                                    m_worldOffset, m_worldOffset + DefaultRegionSize, true);
             }
         });
     }
@@ -194,10 +201,10 @@ public class BSTerrainManager
     // The 'doNow' boolean says whether to do all the unmanaged activities right now (like when
     //     calling this routine from initialization or taint-time routines) or whether to delay
     //     all the unmanaged activities to taint-time.
-    private void UpdateOrCreateTerrain(uint id, float[] heightMap, Vector3 minCoords, Vector3 maxCoords, bool doNow)
+    private void UpdateOrCreateTerrain(uint id, float[] heightMap, Vector3 minCoords, Vector3 maxCoords, bool atTaintTime)
     {
-        DetailLog("{0},BSTerrainManager.UpdateOrCreateTerrain,call,minC={1},maxC={2},doNow={3}",
-                            BSScene.DetailLogZero, minCoords, maxCoords, doNow);
+        DetailLog("{0},BSTerrainManager.UpdateOrCreateTerrain,call,minC={1},maxC={2},atTaintTime={3}",
+                            BSScene.DetailLogZero, minCoords, maxCoords, atTaintTime);
 
         float minZ = float.MaxValue;
         float maxZ = float.MinValue;
@@ -227,12 +234,12 @@ public class BSTerrainManager
             mapInfo.maxZ = maxZ;
             mapInfo.sizeX = maxCoords.X - minCoords.X;
             mapInfo.sizeY = maxCoords.Y - minCoords.Y;
-            DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,call,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}", 
+            DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,call,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}",
                         BSScene.DetailLogZero, terrainRegionBase, mapInfo.minCoords, mapInfo.maxCoords, mapInfo.sizeX, mapInfo.sizeY);
 
             BSScene.TaintCallback rebuildOperation = delegate()
             {
-                if (m_parentScene != null)
+                if (MegaRegionParentPhysicsScene != null)
                 {
                     // It's possible that Combine() was called after this code was queued.
                     // If we are a child of combined regions, we don't create any terrain for us.
@@ -245,17 +252,17 @@ public class BSTerrainManager
                     return;
                 }
 
-                if (mapInfo.terrainBody.Ptr != IntPtr.Zero)
+                if (mapInfo.terrainBody.ptr != IntPtr.Zero)
                 {
                     // Updating an existing terrain.
-                    DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,taint,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}", 
+                    DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,taint,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}",
                                     BSScene.DetailLogZero, terrainRegionBase, mapInfo.minCoords, mapInfo.maxCoords, mapInfo.sizeX, mapInfo.sizeY);
 
                     // Remove from the dynamics world because we're going to mangle this object
-                    BulletSimAPI.RemoveObjectFromWorld2(m_physicsScene.World.Ptr, mapInfo.terrainBody.Ptr);
+                    BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
 
                     // Get rid of the old terrain
-                    BulletSimAPI.DestroyObject2(m_physicsScene.World.Ptr, mapInfo.terrainBody.Ptr);
+                    BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
                     BulletSimAPI.ReleaseHeightMapInfo2(mapInfo.Ptr);
                     mapInfo.Ptr = IntPtr.Zero;
 
@@ -282,11 +289,11 @@ public class BSTerrainManager
                 // else
                 {
                     // Creating a new terrain.
-                    DetailLog("{0},UpdateOrCreateTerrain:CreateNewTerrain,taint,baseX={1},baseY={2},minZ={3},maxZ={4}", 
+                    DetailLog("{0},UpdateOrCreateTerrain:CreateNewTerrain,taint,baseX={1},baseY={2},minZ={3},maxZ={4}",
                                     BSScene.DetailLogZero, mapInfo.minCoords.X, mapInfo.minCoords.Y, minZ, maxZ);
 
                     mapInfo.ID = id;
-                    mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(m_physicsScene.World.Ptr, mapInfo.ID,
+                    mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, mapInfo.ID,
                         mapInfo.minCoords, mapInfo.maxCoords, mapInfo.heightMap, TERRAIN_COLLISION_MARGIN);
 
                     // The terrain object initial position is at the center of the object
@@ -296,43 +303,49 @@ public class BSTerrainManager
                     centerPos.Z = minZ + ((maxZ - minZ) / 2f);
 
                     // Create the terrain shape from the mapInfo
-                    mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(mapInfo.Ptr));
+                    mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(mapInfo.Ptr),
+                                ShapeData.PhysicsShapeType.SHAPE_TERRAIN);
 
-                    mapInfo.terrainBody = new BulletBody(mapInfo.ID, 
-                            BulletSimAPI.CreateBodyWithDefaultMotionState2(mapInfo.terrainShape.Ptr, 
-                                            centerPos, Quaternion.Identity)); 
+                    mapInfo.terrainBody = new BulletBody(mapInfo.ID,
+                            BulletSimAPI.CreateBodyWithDefaultMotionState2(mapInfo.terrainShape.ptr,
+                                                        id, centerPos, Quaternion.Identity));
                 }
 
                 // Make sure the entry is in the heightmap table
                 m_heightMaps[terrainRegionBase] = mapInfo;
 
                 // Set current terrain attributes
-                BulletSimAPI.SetFriction2(mapInfo.terrainBody.Ptr, m_physicsScene.Params.terrainFriction);
-                BulletSimAPI.SetHitFraction2(mapInfo.terrainBody.Ptr, m_physicsScene.Params.terrainHitFraction);
-                BulletSimAPI.SetRestitution2(mapInfo.terrainBody.Ptr, m_physicsScene.Params.terrainRestitution);
-                BulletSimAPI.SetCollisionFlags2(mapInfo.terrainBody.Ptr, CollisionFlags.CF_STATIC_OBJECT);
+                BulletSimAPI.SetFriction2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainFriction);
+                BulletSimAPI.SetHitFraction2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainHitFraction);
+                BulletSimAPI.SetRestitution2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainRestitution);
+                BulletSimAPI.SetCollisionFlags2(mapInfo.terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
 
-                BulletSimAPI.SetMassProps2(mapInfo.terrainBody.Ptr, 0f, Vector3.Zero);
-                BulletSimAPI.UpdateInertiaTensor2(mapInfo.terrainBody.Ptr);
+                BulletSimAPI.SetMassProps2(mapInfo.terrainBody.ptr, 0f, Vector3.Zero);
+                BulletSimAPI.UpdateInertiaTensor2(mapInfo.terrainBody.ptr);
 
                 // Return the new terrain to the world of physical objects
-                BulletSimAPI.AddObjectToWorld2(m_physicsScene.World.Ptr, mapInfo.terrainBody.Ptr);
+                BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
 
                 // redo its bounding box now that it is in the world
-                BulletSimAPI.UpdateSingleAabb2(m_physicsScene.World.Ptr, mapInfo.terrainBody.Ptr);
+                BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
+
+                BulletSimAPI.SetCollisionFilterMask2(mapInfo.terrainBody.ptr,
+                                    (uint)CollisionFilterGroups.TerrainFilter,
+                                    (uint)CollisionFilterGroups.TerrainMask);
 
                 // Make sure the new shape is processed.
-                BulletSimAPI.Activate2(mapInfo.terrainBody.Ptr, true);
+                // BulletSimAPI.Activate2(mapInfo.terrainBody.ptr, true);
+                BulletSimAPI.ForceActivationState2(mapInfo.terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
 
                 m_terrainModified = true;
             };
 
             // There is the option to do the changes now (we're already in 'taint time'), or
             //     to do the Bullet operations later.
-            if (doNow)
+            if (atTaintTime)
                 rebuildOperation();
             else
-                m_physicsScene.TaintedObject("BSScene.UpdateOrCreateTerrain:UpdateExisting", rebuildOperation);
+                PhysicsScene.TaintedObject("BSScene.UpdateOrCreateTerrain:UpdateExisting", rebuildOperation);
         }
         else
         {
@@ -348,7 +361,7 @@ public class BSTerrainManager
             Vector3 minCoordsX = minCoords;
             Vector3 maxCoordsX = maxCoords;
 
-            DetailLog("{0},UpdateOrCreateTerrain:NewTerrain,call,id={1}, minC={2}, maxC={3}", 
+            DetailLog("{0},UpdateOrCreateTerrain:NewTerrain,call,id={1}, minC={2}, maxC={3}",
                             BSScene.DetailLogZero, newTerrainID, minCoords, minCoords);
 
             // Code that must happen at taint-time
@@ -357,7 +370,7 @@ public class BSTerrainManager
                 DetailLog("{0},UpdateOrCreateTerrain:NewTerrain,taint,baseX={1},baseY={2}", BSScene.DetailLogZero, minCoords.X, minCoords.Y);
                 // Create a new mapInfo that will be filled with the new info
                 mapInfo = new BulletHeightMapInfo(id, heightMapX,
-                        BulletSimAPI.CreateHeightMapInfo2(m_physicsScene.World.Ptr, newTerrainID, 
+                        BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, newTerrainID,
                                     minCoordsX, maxCoordsX, heightMapX, TERRAIN_COLLISION_MARGIN));
                 // Put the unfilled heightmap info into the collection of same
                 m_heightMaps.Add(terrainRegionBase, mapInfo);
@@ -368,10 +381,10 @@ public class BSTerrainManager
             };
 
             // If already in taint-time, just call Bullet. Otherwise queue the operations for the safe time.
-            if (doNow)
+            if (atTaintTime)
                 createOperation();
             else
-                m_physicsScene.TaintedObject("BSScene.UpdateOrCreateTerrain:NewTerrain", createOperation);
+                PhysicsScene.TaintedObject("BSScene.UpdateOrCreateTerrain:NewTerrain", createOperation);
         }
     }
 
@@ -419,7 +432,7 @@ public class BSTerrainManager
             catch
             {
                 // Sometimes they give us wonky values of X and Y. Give a warning and return something.
-                m_physicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, x={2}, y={3}",
+                PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, x={2}, y={3}",
                                     LogHeader, terrainBaseXY, regionX, regionY);
                 ret = HEIGHT_GETHEIGHT_RET;
             }
@@ -428,8 +441,8 @@ public class BSTerrainManager
         }
         else
         {
-            m_physicsScene.Logger.ErrorFormat("{0} GetTerrainHeightAtXY: terrain not found: region={1}, x={2}, y={3}",
-                    LogHeader, m_physicsScene.RegionName, tX, tY);
+            PhysicsScene.Logger.ErrorFormat("{0} GetTerrainHeightAtXY: terrain not found: region={1}, x={2}, y={3}",
+                    LogHeader, PhysicsScene.RegionName, tX, tY);
         }
         m_terrainModified = false;
         lastHeight = ret;
@@ -441,7 +454,7 @@ public class BSTerrainManager
     {
         return true;
     }
-    
+
     // This routine is called two ways:
     //    One with 'offset' and 'pScene' zero and null but 'extents' giving the maximum
     //        extent of the combined regions. This is to inform the parent of the size
@@ -453,14 +466,14 @@ public class BSTerrainManager
     {
         m_worldOffset = offset;
         m_worldMax = extents;
-        m_parentScene = pScene;
+        MegaRegionParentPhysicsScene = pScene;
         if (pScene != null)
         {
-            // We are a child. 
+            // We are a child.
             // We want m_worldMax to be the highest coordinate of our piece of terrain.
             m_worldMax = offset + DefaultRegionSize;
         }
-        DetailLog("{0},BSTerrainManager.Combine,offset={1},extents={2},wOffset={3},wMax={4}", 
+        DetailLog("{0},BSTerrainManager.Combine,offset={1},extents={2},wOffset={3},wMax={4}",
                         BSScene.DetailLogZero, offset, extents, m_worldOffset, m_worldMax);
     }
 
@@ -474,7 +487,7 @@ public class BSTerrainManager
 
     private void DetailLog(string msg, params Object[] args)
     {
-        m_physicsScene.PhysicsLogging.Write(msg, args);
+        PhysicsScene.PhysicsLogging.Write(msg, args);
     }
 }
 }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
index 9221cdb..1125d7e 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
@@ -38,35 +38,112 @@ namespace OpenSim.Region.Physics.BulletSPlugin {
 // The physics engine controller class created at initialization
 public struct BulletSim
 {
-    public BulletSim(uint worldId, BSScene bss, IntPtr xx) { worldID = worldId; scene = bss;  Ptr = xx; }
+    public BulletSim(uint worldId, BSScene bss, IntPtr xx)
+    {
+        ptr = xx;
+        worldID = worldId;
+        physicsScene = bss;
+    }
+    public IntPtr ptr;
     public uint worldID;
     // The scene is only in here so very low level routines have a handle to print debug/error messages
-    public BSScene scene;
-    public IntPtr Ptr;
+    public BSScene physicsScene;
+}
+
+// An allocated Bullet btRigidBody
+public struct BulletBody
+{
+    public BulletBody(uint id, IntPtr xx)
+    {
+        ID = id;
+        ptr = xx;
+        collisionFilter = 0;
+        collisionMask = 0;
+    }
+    public IntPtr ptr;
+    public uint ID;
+    public CollisionFilterGroups collisionFilter;
+    public CollisionFilterGroups collisionMask;
+    public override string ToString()
+    {
+        StringBuilder buff = new StringBuilder();
+        buff.Append("<id=");
+        buff.Append(ID.ToString());
+        buff.Append(",p=");
+        buff.Append(ptr.ToString("X"));
+        if (collisionFilter != 0 && collisionMask != 0)
+        {
+            buff.Append(",f=");
+            buff.Append(collisionFilter.ToString("X"));
+            buff.Append(",m=");
+            buff.Append(collisionMask.ToString("X"));
+        }
+        buff.Append(">");
+        return buff.ToString();
+    }
 }
 
 public struct BulletShape
 {
-    public BulletShape(IntPtr xx) { Ptr = xx; }
-    public IntPtr Ptr;
+    public BulletShape(IntPtr xx)
+    {
+        ptr = xx;
+        type=ShapeData.PhysicsShapeType.SHAPE_UNKNOWN;
+        shapeKey = 0;
+        isNativeShape = false;
+    }
+    public BulletShape(IntPtr xx, ShapeData.PhysicsShapeType typ)
+    {
+        ptr = xx;
+        type = typ;
+        shapeKey = 0;
+        isNativeShape = false;
+    }
+    public IntPtr ptr;
+    public ShapeData.PhysicsShapeType type;
+    public ulong shapeKey;
+    public bool isNativeShape;
+    // Hulls have an underlying mesh. A pointer to it is hidden here.
+    public override string ToString()
+    {
+        StringBuilder buff = new StringBuilder();
+        buff.Append("<p=");
+        buff.Append(ptr.ToString("X"));
+        buff.Append(",s=");
+        buff.Append(type.ToString());
+        buff.Append(",k=");
+        buff.Append(shapeKey.ToString("X"));
+        buff.Append(",n=");
+        buff.Append(isNativeShape.ToString());
+        buff.Append(">");
+        return buff.ToString();
+    }
 }
 
-// An allocated Bullet btRigidBody
-public struct BulletBody
+    // Constraint type values as defined by Bullet
+public enum ConstraintType : int
 {
-    public BulletBody(uint id, IntPtr xx) { ID = id;  Ptr = xx; }
-    public IntPtr Ptr;
-    public uint ID;
+        POINT2POINT_CONSTRAINT_TYPE = 3,
+        HINGE_CONSTRAINT_TYPE,
+        CONETWIST_CONSTRAINT_TYPE,
+        D6_CONSTRAINT_TYPE,
+        SLIDER_CONSTRAINT_TYPE,
+        CONTACT_CONSTRAINT_TYPE,
+        D6_SPRING_CONSTRAINT_TYPE,
+        MAX_CONSTRAINT_TYPE
 }
 
 // An allocated Bullet btConstraint
 public struct BulletConstraint
 {
-    public BulletConstraint(IntPtr xx) { Ptr = xx; }
-    public IntPtr Ptr;
+    public BulletConstraint(IntPtr xx)
+    {
+        ptr = xx;
+    }
+    public IntPtr ptr;
 }
 
-// An allocated HeightMapThing which hold various heightmap info
+// An allocated HeightMapThing which holds various heightmap info.
 // Made a class rather than a struct so there would be only one
 //      instance of this and C# will pass around pointers rather
 //      than making copies.
@@ -96,14 +173,14 @@ public class BulletHeightMapInfo
 
 // ===============================================================================
 [StructLayout(LayoutKind.Sequential)]
-public struct ConvexHull 
+public struct ConvexHull
 {
         Vector3 Offset;
         int VertexCount;
         Vector3[] Vertices;
 }
 [StructLayout(LayoutKind.Sequential)]
-public struct ShapeData 
+public struct ShapeData
 {
     public enum PhysicsShapeType
     {
@@ -114,7 +191,9 @@ public struct ShapeData
                 SHAPE_CYLINDER  = 4,
                 SHAPE_SPHERE    = 5,
                 SHAPE_MESH      = 6,
-                SHAPE_HULL      = 7
+                SHAPE_HULL      = 7,
+                SHAPE_GROUNDPLANE  = 8,
+                SHAPE_TERRAIN   = 9,
     };
     public uint ID;
     public PhysicsShapeType Type;
@@ -130,13 +209,24 @@ public struct ShapeData
     public float Restitution;
     public float Collidable;    // true of things bump into this
     public float Static;        // true if a static object. Otherwise gravity, etc.
+    public float Solid;         // true if object cannot be passed through
+    public Vector3 Size;
 
     // note that bools are passed as floats since bool size changes by language and architecture
     public const float numericTrue = 1f;
     public const float numericFalse = 0f;
+
+    // The native shapes have predefined shape hash keys
+    public enum FixedShapeKey : ulong
+    {
+        KEY_BOX         = 1,
+        KEY_SPHERE      = 2,
+        KEY_CONE        = 3,
+        KEY_CYLINDER    = 4,
+    }
 }
 [StructLayout(LayoutKind.Sequential)]
-public struct SweepHit 
+public struct SweepHit
 {
     public uint ID;
     public float Fraction;
@@ -227,7 +317,17 @@ public enum ActivationState : uint
     ISLAND_SLEEPING,
     WANTS_DEACTIVATION,
     DISABLE_DEACTIVATION,
-    DISABLE_SIMULATION
+    DISABLE_SIMULATION,
+}
+
+public enum CollisionObjectTypes : int
+{
+    CO_COLLISION_OBJECT             = 1 << 0,
+    CO_RIGID_BODY                   = 1 << 1,
+    CO_GHOST_OBJECT                 = 1 << 2,
+    CO_SOFT_BODY                    = 1 << 3,
+    CO_HF_FLUID                     = 1 << 4,
+    CO_USER_TYPE                    = 1 << 5,
 }
 
 // Values used by Bullet and BulletSim to control object properties.
@@ -244,77 +344,60 @@ public enum CollisionFlags : uint
     CF_DISABLE_SPU_COLLISION_PROCESS = 1 << 6,
     // Following used by BulletSim to control collisions
     BS_SUBSCRIBE_COLLISION_EVENTS    = 1 << 10,
-    BS_VOLUME_DETECT_OBJECT          = 1 << 11,
-    BS_PHANTOM_OBJECT                = 1 << 12,
-    BS_PHYSICAL_OBJECT               = 1 << 13,
-    BS_TERRAIN_OBJECT                = 1 << 14,
+    // BS_VOLUME_DETECT_OBJECT          = 1 << 11,
+    // BS_PHANTOM_OBJECT                = 1 << 12,
+    // BS_PHYSICAL_OBJECT               = 1 << 13,
+    // BS_TERRAIN_OBJECT                = 1 << 14,
     BS_NONE                          = 0,
-    BS_ALL                           = 0xFFFFFFFF
+    BS_ALL                           = 0xFFFFFFFF,
+
+    // These are the collision flags switched depending on physical state.
+    // The other flags are used for other things and should not be fooled with.
+    BS_ACTIVE = CF_STATIC_OBJECT
+                | CF_KINEMATIC_OBJECT
+                | CF_NO_CONTACT_RESPONSE
+    //            | BS_VOLUME_DETECT_OBJECT
+    //            | BS_PHANTOM_OBJECT
+    //            | BS_PHYSICAL_OBJECT,
 };
 
 // Values for collisions groups and masks
 public enum CollisionFilterGroups : uint
 {
-    NoneFilter              = 0,
-    DefaultFilter           = 1 << 0,
-    StaticFilter            = 1 << 1,
-    KinematicFilter         = 1 << 2,
-    DebrisFilter            = 1 << 3,
-    SensorTrigger           = 1 << 4,
-    CharacterFilter         = 1 << 5,
-    AllFilter               = 0xFFFFFFFF,
+    // Don't use the bit definitions!!  Define the use in a
+    //   filter/mask definition below. This way collision interactions
+    //   are more easily debugged.
+    BNoneFilter              = 0,
+    BDefaultFilter           = 1 << 0,
+    BStaticFilter            = 1 << 1,
+    BKinematicFilter         = 1 << 2,
+    BDebrisFilter            = 1 << 3,
+    BSensorTrigger           = 1 << 4,
+    BCharacterFilter         = 1 << 5,
+    BAllFilter               = 0xFFFFFFFF,
     // Filter groups defined by BulletSim
-    GroundPlaneFilter       = 1 << 10,
-    TerrainFilter           = 1 << 11,
-    RaycastFilter           = 1 << 12,
-    SolidFilter             = 1 << 13,
-};
+    BGroundPlaneFilter       = 1 << 10,
+    BTerrainFilter           = 1 << 11,
+    BRaycastFilter           = 1 << 12,
+    BSolidFilter             = 1 << 13,
+
+    // The collsion filters and masked are defined in one place -- don't want them scattered
+    AvatarFilter            = BCharacterFilter,
+    AvatarMask              = BAllFilter,
+    ObjectFilter            = BSolidFilter,
+    ObjectMask              = BAllFilter,
+    StaticObjectFilter      = BStaticFilter,
+    StaticObjectMask        = BAllFilter,
+    VolumeDetectFilter      = BSensorTrigger,
+    VolumeDetectMask        = ~BSensorTrigger,
+    TerrainFilter           = BTerrainFilter,
+    TerrainMask             = BAllFilter & ~BStaticFilter,
+    GroundPlaneFilter       = BAllFilter,
+    GroundPlaneMask         = BAllFilter
 
-    // For each type, we first clear and then set the collision flags
-public enum ClearCollisionFlag : uint
-{
-    Terrain = CollisionFlags.BS_ALL,
-    Phantom = CollisionFlags.BS_ALL,
-    VolumeDetect = CollisionFlags.BS_ALL,
-    PhysicalObject = CollisionFlags.BS_ALL,
-    StaticObject = CollisionFlags.BS_ALL
-}
+};
 
-public enum SetCollisionFlag : uint
-{
-    Terrain = CollisionFlags.CF_STATIC_OBJECT
-        | CollisionFlags.BS_TERRAIN_OBJECT,
-    Phantom = CollisionFlags.CF_STATIC_OBJECT
-        | CollisionFlags.BS_PHANTOM_OBJECT
-        | CollisionFlags.CF_NO_CONTACT_RESPONSE,
-    VolumeDetect = CollisionFlags.CF_STATIC_OBJECT
-        | CollisionFlags.BS_VOLUME_DETECT_OBJECT
-        | CollisionFlags.CF_NO_CONTACT_RESPONSE,
-    PhysicalObject = CollisionFlags.BS_PHYSICAL_OBJECT,
-    StaticObject = CollisionFlags.CF_STATIC_OBJECT,
-}
 
-// Collision filters used for different types of objects
-public enum SetCollisionFilter : uint
-{
-    Terrain = CollisionFilterGroups.AllFilter,
-    Phantom = CollisionFilterGroups.GroundPlaneFilter
-        | CollisionFilterGroups.TerrainFilter,
-    VolumeDetect = CollisionFilterGroups.AllFilter,
-    PhysicalObject = CollisionFilterGroups.AllFilter,
-    StaticObject = CollisionFilterGroups.AllFilter,
-}
-
-// Collision masks used for different types of objects
-public enum SetCollisionMask : uint
-{
-    Terrain = CollisionFilterGroups.AllFilter,
-    Phantom = CollisionFilterGroups.GroundPlaneFilter
-        | CollisionFilterGroups.TerrainFilter,
-    VolumeDetect = CollisionFilterGroups.AllFilter,
-    PhysicalObject = CollisionFilterGroups.AllFilter,
-    StaticObject = CollisionFilterGroups.AllFilter
-}
 
 // CFM controls the 'hardness' of the constraint. 0=fixed, 0..1=violatable. Default=0
 // ERP controls amount of correction per tick. Usable range=0.1..0.8. Default=0.2.
@@ -350,8 +433,8 @@ public delegate void DebugLogCallback([MarshalAs(UnmanagedType.LPStr)]string msg
 public static extern string GetVersion();
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern uint Initialize(Vector3 maxPosition, IntPtr parms, 
-                        int maxCollisions, IntPtr collisionArray, 
+public static extern uint Initialize(Vector3 maxPosition, IntPtr parms,
+                        int maxCollisions, IntPtr collisionArray,
                         int maxUpdates, IntPtr updateArray,
                         DebugLogCallback logRoutine);
 
@@ -370,19 +453,19 @@ public static extern bool UpdateParameter(uint worldID, uint localID,
 
 // ===============================================================================
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern int PhysicsStep(uint worldID, float timeStep, int maxSubSteps, float fixedTimeStep, 
-                        out int updatedEntityCount, 
+public static extern int PhysicsStep(uint worldID, float timeStep, int maxSubSteps, float fixedTimeStep,
+                        out int updatedEntityCount,
                         out IntPtr updatedEntitiesPtr,
                         out int collidersCount,
                         out IntPtr collidersPtr);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern bool CreateHull(uint worldID, System.UInt64 meshKey, 
+public static extern bool CreateHull(uint worldID, System.UInt64 meshKey,
                             int hullCount, [MarshalAs(UnmanagedType.LPArray)] float[] hulls
     );
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern bool CreateMesh(uint worldID, System.UInt64 meshKey, 
+public static extern bool CreateMesh(uint worldID, System.UInt64 meshKey,
                             int indexCount, [MarshalAs(UnmanagedType.LPArray)] int[] indices,
                             int verticesCount, [MarshalAs(UnmanagedType.LPArray)] float[] vertices
     );
@@ -496,7 +579,7 @@ public static extern void Shutdown2(IntPtr sim);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern int PhysicsStep2(IntPtr world, float timeStep, int maxSubSteps, float fixedTimeStep,
-                        out int updatedEntityCount, 
+                        out int updatedEntityCount,
                         out IntPtr updatedEntitiesPtr,
                         out int collidersCount,
                         out IntPtr collidersPtr);
@@ -507,8 +590,8 @@ public static extern bool PushUpdate2(IntPtr obj);
 // =====================================================================================
 // Mesh, hull, shape and body creation helper routines
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr CreateMeshShape2(IntPtr world, 
-                int indicesCount, [MarshalAs(UnmanagedType.LPArray)] int[] indices, 
+public static extern IntPtr CreateMeshShape2(IntPtr world,
+                int indicesCount, [MarshalAs(UnmanagedType.LPArray)] int[] indices,
                 int verticesCount, [MarshalAs(UnmanagedType.LPArray)] float[] vertices );
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
@@ -516,11 +599,10 @@ public static extern IntPtr CreateHullShape2(IntPtr world,
                 int hullCount, [MarshalAs(UnmanagedType.LPArray)] float[] hulls);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr BuildHullShape2(IntPtr world, IntPtr meshShape);
+public static extern IntPtr BuildHullShapeFromMesh2(IntPtr world, IntPtr meshShape);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr BuildNativeShape2(IntPtr world,
-                float shapeType, float collisionMargin, Vector3 scale);
+public static extern IntPtr BuildNativeShape2(IntPtr world, ShapeData shapeData);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern bool IsNativeShape2(IntPtr shape);
@@ -535,16 +617,25 @@ public static extern void AddChildToCompoundShape2(IntPtr cShape, IntPtr addShap
 public static extern void RemoveChildFromCompoundShape2(IntPtr cShape, IntPtr removeShape);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr CreateBodyFromShapeAndInfo2(IntPtr sim, IntPtr shape, IntPtr constructionInfo);
+public static extern IntPtr DuplicateCollisionShape2(IntPtr sim, IntPtr srcShape, uint id);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern IntPtr CreateBodyFromShapeAndInfo2(IntPtr sim, IntPtr shape, uint id, IntPtr constructionInfo);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern bool DeleteCollisionShape2(IntPtr world, IntPtr shape);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr CreateBodyFromShape2(IntPtr sim, IntPtr shape, Vector3 pos, Quaternion rot);
+public static extern int GetBodyType2(IntPtr obj);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern IntPtr CreateBodyFromShape2(IntPtr sim, IntPtr shape, uint id, Vector3 pos, Quaternion rot);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr CreateBodyWithDefaultMotionState2(IntPtr shape, Vector3 pos, Quaternion rot);
+public static extern IntPtr CreateBodyWithDefaultMotionState2(IntPtr shape, uint id, Vector3 pos, Quaternion rot);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern IntPtr CreateGhostFromShape2(IntPtr sim, IntPtr shape, uint id, Vector3 pos, Quaternion rot);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern IntPtr AllocateBodyInfo2(IntPtr obj);
@@ -558,11 +649,11 @@ public static extern void DestroyObject2(IntPtr sim, IntPtr obj);
 // =====================================================================================
 // Terrain creation and helper routines
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr CreateHeightMapInfo2(IntPtr sim, uint id, Vector3 minCoords, Vector3 maxCoords, 
+public static extern IntPtr CreateHeightMapInfo2(IntPtr sim, uint id, Vector3 minCoords, Vector3 maxCoords,
         [MarshalAs(UnmanagedType.LPArray)] float[] heightMap, float collisionMargin);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern IntPtr FillHeightMapInfo2(IntPtr sim, IntPtr mapInfo, uint id, Vector3 minCoords, Vector3 maxCoords, 
+public static extern IntPtr FillHeightMapInfo2(IntPtr sim, IntPtr mapInfo, uint id, Vector3 minCoords, Vector3 maxCoords,
         [MarshalAs(UnmanagedType.LPArray)] float[] heightMap, float collisionMargin);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
@@ -600,7 +691,7 @@ public static extern void SetConstraintEnable2(IntPtr constrain, float numericTr
 public static extern void SetConstraintNumSolverIterations2(IntPtr constrain, float iterations);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern bool SetFrames2(IntPtr constrain, 
+public static extern bool SetFrames2(IntPtr constrain,
                 Vector3 frameA, Quaternion frameArot, Vector3 frameB, Quaternion frameBrot);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
@@ -963,6 +1054,9 @@ public static extern Vector3 GetPushVelocity2(IntPtr obj);
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern Vector3 GetTurnVelocity2(IntPtr obj);
 
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern void SetCollisionFilterMask2(IntPtr body, uint filter, uint mask);
+
 // =====================================================================================
 // btCollisionShape entries
 
@@ -1014,9 +1108,6 @@ public static extern void SetMargin2(IntPtr shape, float val);
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern float GetMargin2(IntPtr shape);
 
-[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
-public static extern void SetCollisionFilterMask(IntPtr shape, uint filter, uint mask);
-
 // =====================================================================================
 // Debugging
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index bd83bee..6e6a089 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -936,10 +936,10 @@
     MaxPersistantManifoldPoolSize = 0
     ShouldDisableContactPoolDynamicAllocation = False
     ShouldForceUpdateAllAabbs = False
-    ShouldRandomizeSolverOrder = False
-    ShouldSplitSimulationIslands = False
+    ShouldRandomizeSolverOrder = True
+    ShouldSplitSimulationIslands = True
     ShouldEnableFrictionCaching = False
-    NumberOfSolverIterations = 0;   
+    NumberOfSolverIterations = 0   
 
     ; Linkset constraint parameters
     LinkConstraintUseFrameOffset = False
diff --git a/bin/lib32/BulletSim.dll b/bin/lib32/BulletSim.dll
index 3b35a98..da6e31c 100755
--- a/bin/lib32/BulletSim.dll
+++ b/bin/lib32/BulletSim.dll
diff --git a/bin/lib32/libBulletSim.so b/bin/lib32/libBulletSim.so
index 65eba37..9503cdb 100755
--- a/bin/lib32/libBulletSim.so
+++ b/bin/lib32/libBulletSim.so
diff --git a/bin/lib64/BulletSim.dll b/bin/lib64/BulletSim.dll
index f01655b..1782c8e 100755
--- a/bin/lib64/BulletSim.dll
+++ b/bin/lib64/BulletSim.dll
diff --git a/bin/lib64/libBulletSim.so b/bin/lib64/libBulletSim.so
index 5302e29..06e6ce2 100755
--- a/bin/lib64/libBulletSim.so
+++ b/bin/lib64/libBulletSim.so