1 files changed, 731 insertions, 661 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 9c20004..5d16bbf 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -24,6 +24,7 @@
  * (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.Reflection;
 using System.Collections.Generic;
@@ -36,32 +37,17 @@ using OpenSim.Region.Physics.ConvexDecompositionDotNet;
 
 namespace OpenSim.Region.Physics.BulletSPlugin
 {
+
     [Serializable]
-public sealed class BSPrim : PhysicsActor
+public sealed class BSPrim : BSPhysObject
 {
     private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
     private static readonly string LogHeader = "[BULLETS PRIM]";
 
-    private void DebugLog(string mm, params Object[] xx) { if (_scene.ShouldDebugLog) m_log.DebugFormat(mm, xx); }
-
-    private IMesh _mesh;
-    private PrimitiveBaseShape _pbs;
-    private ShapeData.PhysicsShapeType _shapeType;
-    private ulong _meshKey;
-    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.
+    // _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
-    private OMV.Vector3 _scale; // the multiplier for each mesh dimension for the mesh as created by the meshmerizer
 
-    private bool _stopped;
     private bool _grabbed;
     private bool _isSelected;
     private bool _isVolumeDetect;
@@ -89,25 +75,6 @@ public sealed class BSPrim : PhysicsActor
     private bool _kinematic;
     private float _buoyancy;
 
-    // Membership in a linkset is controlled by this class.
-    private BSLinkset _linkset;
-    public BSLinkset Linkset
-    {
-        get { return _linkset; }
-        set { _linkset = value; }
-    }
-
-    private int _subscribedEventsMs = 0;
-    private int _nextCollisionOkTime = 0;
-    long _collidingStep;
-    long _collidingGroundStep;
-
-    private BulletBody m_body;
-    public BulletBody Body { 
-        get { return m_body; }
-        set { m_body = value; }
-    }
-
     private BSDynamics _vehicle;
 
     private OMV.Vector3 _PIDTarget;
@@ -120,110 +87,116 @@ public sealed class BSPrim : PhysicsActor
 
     public BSPrim(uint localID, String primName, BSScene parent_scene, OMV.Vector3 pos, OMV.Vector3 size,
                        OMV.Quaternion rotation, PrimitiveBaseShape pbs, bool pisPhysical)
+            : base(parent_scene, localID, primName, "BSPrim")
     {
         // m_log.DebugFormat("{0}: BSPrim creation of {1}, id={2}", LogHeader, primName, localID);
-        _localID = localID;
-        _avName = primName;
-        _scene = parent_scene;
+        _physicsActorType = (int)ActorTypes.Prim;
         _position = pos;
         _size = size;
-        _scale = new OMV.Vector3(1f, 1f, 1f);   // the scale will be set by CreateGeom depending on object type
+        Scale = size;   // the scale will be set by CreateGeom depending on object type
         _orientation = rotation;
         _buoyancy = 1f;
         _velocity = OMV.Vector3.Zero;
         _rotationalVelocity = OMV.Vector3.Zero;
-        _hullKey = 0;
-        _meshKey = 0;
-        _pbs = pbs;
+        BaseShape = 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(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();
-        // do the actual object creation at taint time
+
+        // No body or shape yet
+        PhysBody = new BulletBody(LocalID, IntPtr.Zero);
+        PhysShape = new BulletShape(IntPtr.Zero);
+
         DetailLog("{0},BSPrim.constructor,call", LocalID);
-        _scene.TaintedObject("BSPrim.create", delegate()
+        // do the actual object creation at taint time
+        PhysicsScene.TaintedObject("BSPrim.create", delegate()
         {
-            RecreateGeomAndObject();
+            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.
-            m_body = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(_scene.World.Ptr, LocalID));
+            CurrentCollisionFlags = BulletSimAPI.GetCollisionFlags2(PhysBody.ptr);
         });
     }
 
     // called when this prim is being destroyed and we should free all the resources
-    public void Destroy()
+    public override void Destroy()
     {
         // m_log.DebugFormat("{0}: Destroy, id={1}", LogHeader, LocalID);
 
         // Undo any links between me and any other object
-        BSPrim parentBefore = _linkset.LinksetRoot;
-        int childrenBefore = _linkset.NumberOfChildren;
+        BSPhysObject parentBefore = Linkset.LinksetRoot;
+        int childrenBefore = Linkset.NumberOfChildren;
 
-        _linkset = _linkset.RemoveMeFromLinkset(this);
+        Linkset = Linkset.RemoveMeFromLinkset(this);
 
         DetailLog("{0},BSPrim.Destroy,call,parentBefore={1},childrenBefore={2},parentAfter={3},childrenAfter={4}",
-            LocalID, parentBefore.LocalID, childrenBefore, _linkset.LinksetRoot.LocalID, _linkset.NumberOfChildren);
+            LocalID, parentBefore.LocalID, childrenBefore, Linkset.LinksetRoot.LocalID, Linkset.NumberOfChildren);
 
         // 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(PhysBody, true, null);
+            PhysicsScene.Shapes.DereferenceShape(PhysShape, true, null);
         });
     }
-    
-    public override bool Stopped { 
-        get { return _stopped; } 
+
+    // No one uses this property.
+    public override bool Stopped {
+        get { return false; }
     }
-    public override OMV.Vector3 Size { 
-        get { return _size; } 
+    public override OMV.Vector3 Size {
+        get { return _size; }
         set {
+            // We presume the scale and size are the same. If scale must be changed for
+            //     the physical shape, that is done when the geometry is built.
             _size = value;
-            _scene.TaintedObject("BSPrim.setSize", delegate()
-            {
-                _mass = CalculateMass();   // changing size changes the mass
-                BulletSimAPI.SetObjectScaleMass(_scene.WorldID, _localID, _scale, (IsPhysical ? _mass : 0f), IsPhysical);
-                // DetailLog("{0}: BSPrim.setSize: size={1}, mass={2}, physical={3}", LocalID, _size, _mass, IsPhysical);
-                RecreateGeomAndObject();
-            });
-        } 
+            ForceBodyShapeRebuild(false);
+        }
     }
-    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 override OMV.Vector3 Scale { get; set; }
+
+    public override PrimitiveBaseShape Shape {
         set {
-            _pbs = value;
-            _scene.TaintedObject("BSPrim.setShape", delegate()
-            {
-                _mass = CalculateMass();   // changing the shape changes the mass
-                RecreateGeomAndObject();
-            });
-        } 
+            BaseShape = value;
+            ForceBodyShapeRebuild(false);
+        }
     }
-    public override uint LocalID { 
-        set { _localID = value; }
-        get { return _localID; }
+    // Whatever the linkset wants is what I want.
+    public override PhysicsShapeType PreferredPhysicalShape
+        { get { return Linkset.PreferredPhysicalShape(this); } }
+
+    public override bool ForceBodyShapeRebuild(bool inTaintTime)
+    {
+        LastAssetBuildFailed = false;
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ForceBodyShapeRebuild", delegate()
+        {
+            _mass = CalculateMass();   // changing the shape changes the mass
+            CreateGeomAndObject(true);
+        });
+        return true;
     }
-    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; }
 
@@ -232,158 +205,260 @@ public sealed class BSPrim : PhysicsActor
         BSPrim parent = obj as BSPrim;
         if (parent != null)
         {
-            DebugLog("{0}: link {1}/{2} to {3}", LogHeader, _avName, _localID, parent.LocalID);
-            BSPrim parentBefore = _linkset.LinksetRoot;
-            int childrenBefore = _linkset.NumberOfChildren;
+            BSPhysObject parentBefore = Linkset.LinksetRoot;
+            int childrenBefore = Linkset.NumberOfChildren;
 
-            _linkset = parent.Linkset.AddMeToLinkset(this);
+            Linkset = parent.Linkset.AddMeToLinkset(this);
 
-            DetailLog("{0},BSPrim.link,call,parentBefore={1}, childrenBefore=={2}, parentAfter={3}, childrenAfter={4}", 
-                LocalID, parentBefore.LocalID, childrenBefore, _linkset.LinksetRoot.LocalID, _linkset.NumberOfChildren);
+            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
     public override void delink() {
         // TODO: decide if this parent checking needs to happen at taint time
         // Race condition here: if link() and delink() in same simulation tick, the delink will not happen
-        DebugLog("{0}: delink {1}/{2}. Parent={3}", LogHeader, _avName, _localID, 
-                            _linkset.LinksetRoot._avName+"/"+_linkset.LinksetRoot.LocalID.ToString());
 
-        BSPrim parentBefore = _linkset.LinksetRoot;
-        int childrenBefore = _linkset.NumberOfChildren;
-        
-        _linkset = _linkset.RemoveMeFromLinkset(this);
+        BSPhysObject parentBefore = Linkset.LinksetRoot;
+        int childrenBefore = Linkset.NumberOfChildren;
+
+        Linkset = Linkset.RemoveMeFromLinkset(this);
 
-        DetailLog("{0},BSPrim.delink,parentBefore={1},childrenBefore={2},parentAfter={3},childrenAfter={4}, ", 
-            LocalID, parentBefore.LocalID, childrenBefore, _linkset.LinksetRoot.LocalID, _linkset.NumberOfChildren);
-        return; 
+        DetailLog("{0},BSPrim.delink,parentBefore={1},childrenBefore={2},parentAfter={3},childrenAfter={4}, ",
+            LocalID, parentBefore.LocalID, childrenBefore, Linkset.LinksetRoot.LocalID, Linkset.NumberOfChildren);
+        return;
     }
 
     // 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 void ZeroMotion()
+    public override void ZeroMotion(bool inTaintTime)
     {
         _velocity = OMV.Vector3.Zero;
         _acceleration = OMV.Vector3.Zero;
         _rotationalVelocity = OMV.Vector3.Zero;
 
-        // Zero some other properties directly into the physics engine
-        BulletSimAPI.SetVelocity2(Body.Ptr, OMV.Vector3.Zero);
-        BulletSimAPI.SetAngularVelocity2(Body.Ptr, OMV.Vector3.Zero);
-        BulletSimAPI.SetInterpolation2(Body.Ptr, OMV.Vector3.Zero, OMV.Vector3.Zero);
-        BulletSimAPI.ClearForces2(Body.Ptr);
+        // Zero some other properties in the physics engine
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ZeroMotion", delegate()
+        {
+            BulletSimAPI.ClearAllForces2(PhysBody.ptr);
+        });
+    }
+    public override void ZeroAngularMotion(bool inTaintTime)
+    {
+        _rotationalVelocity = OMV.Vector3.Zero;
+        // Zero some other properties in the physics engine
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ZeroMotion", delegate()
+        {
+            BulletSimAPI.SetInterpolationAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
+            BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
+        });
     }
 
     public override void LockAngularMotion(OMV.Vector3 axis)
-    { 
-        // DetailLog("{0},BSPrim.LockAngularMotion,call,axis={1}", LocalID, axis);
+    {
+        DetailLog("{0},BSPrim.LockAngularMotion,call,axis={1}", LocalID, axis);
         return;
     }
 
-    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.GetObjectPosition(_scene.WorldID, _localID);
+    public override OMV.Vector3 RawPosition
+    {
+        get { return _position; }
+        set { _position = value; }
+    }
+    public override OMV.Vector3 Position {
+        get {
+            // child prims move around based on their parent. Need to get the latest location
+            if (!Linkset.IsRoot(this))
+                _position = Linkset.Position(this);
 
-            // don't do the GetObjectPosition for root elements because this function is called a zillion times
-            // _position = BulletSimAPI.GetObjectPosition(_scene.WorldID, _localID);
-            return _position; 
-        } 
+            // don't do the GetObjectPosition for root elements because this function is called a zillion times.
+            // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
+            return _position;
+        }
         set {
+            // If the position must be forced into the physics engine, use ForcePosition.
+            if (_position == value)
+            {
+                return;
+            }
             _position = value;
             // TODO: what does it mean to set the position of a child prim?? Rebuild the constraint?
-            _scene.TaintedObject("BSPrim.setPosition", delegate()
+            PositionSanityCheck(false);
+            PhysicsScene.TaintedObject("BSPrim.setPosition", delegate()
             {
                 // DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetObjectTranslation(_scene.WorldID, _localID, _position, _orientation);
+                BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+                ActivateIfPhysical(false);
             });
-        } 
+        }
+    }
+    public override OMV.Vector3 ForcePosition {
+        get {
+            _position = BulletSimAPI.GetPosition2(PhysBody.ptr);
+            return _position;
+        }
+        set {
+            _position = value;
+            // PositionSanityCheck();   // Don't do this! Causes a loop and caller should know better.
+            BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+            ActivateIfPhysical(false);
+        }
+    }
+
+    // Check that the current position is sane and, if not, modify the position to make it so.
+    // Check for being below terrain and being out of bounds.
+    // Returns 'true' of the position was made sane by some action.
+    private bool PositionSanityCheck(bool inTaintTime)
+    {
+        bool ret = false;
+
+        float terrainHeight = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(_position);
+        OMV.Vector3 upForce = OMV.Vector3.Zero;
+        if (Position.Z < terrainHeight)
+        {
+            DetailLog("{0},BSPrim.PositionAdjustUnderGround,call,pos={1},terrain={2}", LocalID, _position, terrainHeight);
+            float targetHeight = terrainHeight + (Size.Z / 2f);
+            // Upforce proportional to the distance away from the terrain. Correct the error in 1 sec.
+            upForce.Z = (terrainHeight - Position.Z) * 1f;
+            ret = true;
+        }
+
+        if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
+        {
+            float waterHeight = PhysicsScene.GetWaterLevelAtXYZ(_position);
+            // TODO: a floating motor so object will bob in the water
+            if (Math.Abs(Position.Z - waterHeight) > 0.1f)
+            {
+                // Upforce proportional to the distance away from the water. Correct the error in 1 sec.
+                upForce.Z = (waterHeight - Position.Z) * 1f;
+                ret = true;
+            }
+        }
+
+        // TODO: check for out of bounds
+
+        // The above code computes a force to apply to correct any out-of-bounds problems. Apply same.
+        if (ret)
+        {
+            PhysicsScene.TaintedObject(inTaintTime, "BSPrim.PositionSanityCheck:belowTerrain", delegate()
+            {
+                // Apply upforce and overcome gravity.
+                ForceVelocity = ForceVelocity + upForce - PhysicsScene.DefaultGravity;
+            });
+        }
+        return ret;
     }
 
     // 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;
+            return Linkset.LinksetMass;
+            // return _mass;
         }
     }
 
     // used when we only want this prim's mass and not the linkset thing
-    public float MassRaw { get { return _mass; } }
+    public override float RawMass { 
+        get { return _mass; }
+    }
+    // Set the physical mass to the passed mass.
+    // Note that this does not change _mass!
+    public override void UpdatePhysicalMassProperties(float physMass)
+    {
+        if (IsStatic)
+        {
+            Inertia = OMV.Vector3.Zero;
+            BulletSimAPI.SetMassProps2(PhysBody.ptr, 0f, Inertia);
+            BulletSimAPI.UpdateInertiaTensor2(PhysBody.ptr);
+        }
+        else
+        {
+            Inertia = BulletSimAPI.CalculateLocalInertia2(PhysShape.ptr, physMass);
+            BulletSimAPI.SetMassProps2(PhysBody.ptr, physMass, Inertia);
+            BulletSimAPI.UpdateInertiaTensor2(PhysBody.ptr);
+            // center of mass is at the zero of the object
+            // DEBUG DEBUG BulletSimAPI.SetCenterOfMassByPosRot2(PhysBody.ptr, ForcePosition, ForceOrientation);
+            DetailLog("{0},BSPrim.UpdateMassProperties,mass={1},localInertia={2}", LocalID, physMass, Inertia);
+        }
+    }
 
     // Is this used?
     public override OMV.Vector3 CenterOfMass
     {
-        get { return _linkset.CenterOfMass; }
+        get { return Linkset.CenterOfMass; }
     }
 
     // Is this used?
     public override OMV.Vector3 GeometricCenter
     {
-        get { return _linkset.GeometricCenter; }
+        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.SetObjectForce(_scene.WorldID, _localID, _force);
-                BulletSimAPI.SetObjectForce2(Body.Ptr, _force);
+                BulletSimAPI.SetObjectForce2(PhysBody.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()
+
+            // Tell the scene about the vehicle so it will get processing each frame.
+            PhysicsScene.VehicleInSceneTypeChanged(this, type);
+
+            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);
+                ActivateIfPhysical(false);
             });
-        } 
+        }
     }
-    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, _scene.LastSimulatedTimestep);
+            _vehicle.ProcessFloatVehicleParam((Vehicle)param, value);
+            ActivateIfPhysical(false);
         });
     }
-    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, _scene.LastSimulatedTimestep);
+            _vehicle.ProcessVectorVehicleParam((Vehicle)param, value);
+            ActivateIfPhysical(false);
         });
     }
-    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);
+            ActivateIfPhysical(false);
         });
     }
-    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);
         });
@@ -391,143 +466,356 @@ public sealed class BSPrim : PhysicsActor
 
     // Called each simulation step to advance vehicle characteristics.
     // Called from Scene when doing simulation step so we're in taint processing time.
-    public void StepVehicle(float timeStep)
+    public override void StepVehicle(float timeStep)
     {
-        if (IsPhysical)
+        if (IsPhysical && _vehicle.IsActive)
+        {
             _vehicle.Step(timeStep);
+            /* // TEST TEST DEBUG DEBUG -- trying to reduce the extra action of Bullet simulation step
+            PhysicsScene.PostTaintObject("BSPrim.StepVehicles", LocalID, delegate()
+            {
+                // This resets the interpolation values and recomputes the tensor variables
+                BulletSimAPI.SetCenterOfMassByPosRot2(BSBody.ptr, ForcePosition, ForceOrientation);
+            });
+             */
+        }
     }
 
     // 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.SetObjectVelocity(_scene.WorldID, LocalID, _velocity);
+                BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
             });
-        } 
+        }
+    }
+    public override OMV.Vector3 ForceVelocity {
+        get { return _velocity; }
+        set {
+            _velocity = value;
+            BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
+        }
     }
-    public override OMV.Vector3 Torque { 
-        get { return _torque; } 
-        set { _torque = value; 
+    public override OMV.Vector3 Torque {
+        get { return _torque; }
+        set {
+            _torque = value;
+            AddAngularForce(_torque, false, false);
             // 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 RawOrientation
+    {
+        get { return _orientation; }
+        set { _orientation = value; }
+    }
+    public override OMV.Quaternion Orientation {
         get {
-            if (!_linkset.IsRoot(this))
+            // Children move around because tied to parent. Get a fresh value.
+            if (!Linkset.IsRoot(this))
             {
-                // Children move around because tied to parent. Get a fresh value.
-                _orientation = BulletSimAPI.GetObjectOrientation(_scene.WorldID, LocalID);
+                _orientation = Linkset.Orientation(this);
             }
             return _orientation;
-        } 
+        }
         set {
+            if (_orientation == value)
+                return;
             _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);
+                // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
                 // DetailLog("{0},BSPrim.setOrientation,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetObjectTranslation(_scene.WorldID, _localID, _position, _orientation);
+                BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
             });
-        } 
+        }
+    }
+    // Go directly to Bullet to get/set the value.
+    public override OMV.Quaternion ForceOrientation
+    {
+        get
+        {
+            _orientation = BulletSimAPI.GetOrientation2(PhysBody.ptr);
+            return _orientation;
+        }
+        set
+        {
+            _orientation = value;
+            BulletSimAPI.SetTranslation2(PhysBody.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);
+                    // whether phys-to-static or static-to-phys, the object is not moving.
+                    ZeroMotion(true);
+                });
+            }
+        }
     }
 
     // An object is static (does not move) if selected or not physical
-    private bool IsStatic
+    public override bool IsStatic
     {
         get { return _isSelected || !IsPhysical; }
     }
 
     // An object is solid if it's not phantom and if it's not doing VolumeDetect
-    private bool IsSolid
+    public override 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
-    private void SetObjectDynamic()
+    // 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 UpdatePhysicalParameters()
     {
-        // RA: remove this for the moment.
-        // The problem is that dynamic objects are hulls so if we are becoming physical
-        //    the shape has to be checked and possibly built.
-        //    Maybe a VerifyCorrectPhysicalShape() routine?
-        // RecreateGeomAndObject();
+        // 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, PhysBody.ptr);
+
+        // Set up the object physicalness (does gravity and collisions move this object)
+        MakeDynamic(IsStatic);
+
+        // Update vehicle specific parameters (after MakeDynamic() so can change physical parameters)
+        _vehicle.Refresh();
 
-        // Bullet wants static objects to have a mass of zero
-        float mass = IsStatic ? 0f : _mass;
+        // Arrange for collision events if the simulator wants them
+        EnableCollisions(SubscribedEvents());
 
-        BulletSimAPI.SetObjectProperties(_scene.WorldID, LocalID, IsStatic, IsSolid, SubscribedEvents(), mass);
+        // Make solid or not (do things bounce off or pass through this object).
+        MakeSolid(IsSolid);
 
-        // recompute any linkset parameters
-        _linkset.Refresh(this);
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, PhysBody.ptr);
 
-        CollisionFlags cf = BulletSimAPI.GetCollisionFlags2(Body.Ptr);
-        // DetailLog("{0},BSPrim.SetObjectDynamic,taint,static={1},solid={2},mass={3}, cf={4}", LocalID, IsStatic, IsSolid, mass, cf);
+        // Rebuild its shape
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, PhysBody.ptr);
+
+        // Collision filter can be set only when the object is in the world
+        if (PhysBody.collisionFilter != 0 || PhysBody.collisionMask != 0)
+        {
+            BulletSimAPI.SetCollisionFilterMask2(PhysBody.ptr, (uint)PhysBody.collisionFilter, (uint)PhysBody.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.
+        // For compound based linksets, this enables and disables interactions of the children.
+        Linkset.Refresh(this);
+
+        DetailLog("{0},BSPrim.UpdatePhysicalParameters,taintExit,static={1},solid={2},mass={3},collide={4},cf={5:X},body={6},shape={7}",
+                        LocalID, IsStatic, IsSolid, _mass, SubscribedEvents(), CurrentCollisionFlags, PhysBody, PhysShape);
+    }
+
+    // "Making dynamic" means changing to and from static.
+    // When static, gravity does not effect the object and it is fixed in space.
+    // When dynamic, the object can fall and be pushed by others.
+    // This is independent of its 'solidness' which controls what passes through
+    //    this object and what interacts with it.
+    private void MakeDynamic(bool makeStatic)
+    {
+        if (makeStatic)
+        {
+            // Become a Bullet 'static' object type
+            CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(PhysBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+            // Stop all movement
+            ZeroMotion(true);
+            // Center of mass is at the center of the object
+            // DEBUG DEBUG BulletSimAPI.SetCenterOfMassByPosRot2(Linkset.LinksetRoot.PhysBody.ptr, _position, _orientation);
+            // Mass is zero which disables a bunch of physics stuff in Bullet
+            UpdatePhysicalMassProperties(0f);
+            // Set collision detection parameters
+            if (PhysicsScene.Params.ccdMotionThreshold > 0f)
+            {
+                BulletSimAPI.SetCcdMotionThreshold2(PhysBody.ptr, PhysicsScene.Params.ccdMotionThreshold);
+                BulletSimAPI.SetCcdSweptSphereRadius2(PhysBody.ptr, PhysicsScene.Params.ccdSweptSphereRadius);
+            }
+            // There can be special things needed for implementing linksets
+            Linkset.MakeStatic(this);
+            // The activation state is 'disabled' so Bullet will not try to act on it.
+            BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.DISABLE_SIMULATION);
+            // Start it out sleeping and physical actions could wake it up.
+            // BulletSimAPI.ForceActivationState2(BSBody.ptr, ActivationState.ISLAND_SLEEPING);
+
+            PhysBody.collisionFilter = CollisionFilterGroups.StaticObjectFilter;
+            PhysBody.collisionMask = CollisionFilterGroups.StaticObjectMask;
+        }
+        else
+        {
+            // Not a Bullet static object
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(PhysBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+            // Set various physical properties so internal dynamic properties will get computed correctly as they are set
+            BulletSimAPI.SetFriction2(PhysBody.ptr, PhysicsScene.Params.defaultFriction);
+            BulletSimAPI.SetRestitution2(PhysBody.ptr, PhysicsScene.Params.defaultRestitution);
+
+            // per http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=3382
+            // Since this can be called multiple times, only zero forces when becoming physical
+            // BulletSimAPI.ClearAllForces2(BSBody.ptr);
+
+            // For good measure, make sure the transform is set through to the motion state
+            BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+
+            // Center of mass is at the center of the object
+            // DEBUG DEBUG BulletSimAPI.SetCenterOfMassByPosRot2(Linkset.LinksetRoot.PhysBody.ptr, _position, _orientation);
+
+            // A dynamic object has mass
+            UpdatePhysicalMassProperties(RawMass);
+
+            // Set collision detection parameters
+            if (PhysicsScene.Params.ccdMotionThreshold > 0f)
+            {
+                BulletSimAPI.SetCcdMotionThreshold2(PhysBody.ptr, PhysicsScene.Params.ccdMotionThreshold);
+                BulletSimAPI.SetCcdSweptSphereRadius2(PhysBody.ptr, PhysicsScene.Params.ccdSweptSphereRadius);
+            }
+
+            // Various values for simulation limits
+            BulletSimAPI.SetDamping2(PhysBody.ptr, PhysicsScene.Params.linearDamping, PhysicsScene.Params.angularDamping);
+            BulletSimAPI.SetDeactivationTime2(PhysBody.ptr, PhysicsScene.Params.deactivationTime);
+            BulletSimAPI.SetSleepingThresholds2(PhysBody.ptr, PhysicsScene.Params.linearSleepingThreshold, PhysicsScene.Params.angularSleepingThreshold);
+            BulletSimAPI.SetContactProcessingThreshold2(PhysBody.ptr, PhysicsScene.Params.contactProcessingThreshold);
+
+            // There might be special things needed for implementing linksets.
+            Linkset.MakeDynamic(this);
+
+            // Force activation of the object so Bullet will act on it.
+            // Must do the ForceActivationState2() to overcome the DISABLE_SIMULATION from static objects.
+            BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.ACTIVE_TAG);
+            // BulletSimAPI.Activate2(BSBody.ptr, true);
+
+            PhysBody.collisionFilter = CollisionFilterGroups.ObjectFilter;
+            PhysBody.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(PhysBody.ptr);
+        if (makeSolid)
+        {
+            // 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(PhysBody.ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
+        }
+        else
+        {
+            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(PhysBody.ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
+            PhysBody.collisionFilter = CollisionFilterGroups.VolumeDetectFilter;
+            PhysBody.collisionMask = CollisionFilterGroups.VolumeDetectMask;
+        }
+    }
+
+    // Enable physical actions. Bullet will keep sleeping non-moving physical objects so
+    //     they need waking up when parameters are changed.
+    // Called in taint-time!!
+    private void ActivateIfPhysical(bool forceIt)
+    {
+        if (IsPhysical)
+            BulletSimAPI.Activate2(PhysBody.ptr, forceIt);
+    }
+
+    // Turn on or off the flag controlling whether collision events are returned to the simulator.
+    private void EnableCollisions(bool wantsCollisionEvents)
+    {
+        if (wantsCollisionEvents)
+        {
+            CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(PhysBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+        }
+        else
+        {
+            CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(PhysBody.ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+        }
     }
 
     // prims don't fly
-    public override bool Flying { 
-        get { return _flying; } 
-        set { _flying = value; } 
+    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 {
@@ -537,10 +825,19 @@ public sealed class BSPrim : PhysicsActor
             return false;
         }
     }
-    public override bool FloatOnWater { 
-        set { _floatOnWater = value; } 
+    public override bool FloatOnWater {
+        set {
+            _floatOnWater = value;
+            PhysicsScene.TaintedObject("BSPrim.setFloatOnWater", delegate()
+            {
+                if (_floatOnWater)
+                    CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(PhysBody.ptr, CollisionFlags.BS_FLOATS_ON_WATER);
+                else
+                    CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(PhysBody.ptr, CollisionFlags.BS_FLOATS_ON_WATER);
+            });
+        }
     }
-    public override OMV.Vector3 RotationalVelocity { 
+    public override OMV.Vector3 RotationalVelocity {
         get {
             /*
             OMV.Vector3 pv = OMV.Vector3.Zero;
@@ -552,58 +849,76 @@ public sealed class BSPrim : PhysicsActor
              */
 
             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.SetObjectAngularVelocity(_scene.WorldID, LocalID, _rotationalVelocity);
+                DetailLog("{0},BSPrim.SetRotationalVel,taint,rotvel={1}", LocalID, _rotationalVelocity);
+                BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
             });
-        } 
+        }
     }
-    public override bool Kinematic { 
-        get { return _kinematic; } 
-        set { _kinematic = value; 
+    public override OMV.Vector3 ForceRotationalVelocity {
+        get {
+            return _rotationalVelocity;
+        }
+        set {
+            _rotationalVelocity = value;
+            BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
+        }
+    }
+    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);
-                BulletSimAPI.SetObjectBuoyancy(_scene.WorldID, _localID, _buoyancy);
+                ForceBuoyancy = _buoyancy;
             });
-        } 
+        }
+    }
+    public override float ForceBuoyancy {
+        get { return _buoyancy; }
+        set {
+            _buoyancy = value;
+            // DetailLog("{0},BSPrim.setForceBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
+            // Buoyancy is faked by changing the gravity applied to the object
+            float grav = PhysicsScene.Params.gravity * (1f - _buoyancy);
+            BulletSimAPI.SetGravity2(PhysBody.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; }
     }
 
@@ -615,6 +930,10 @@ public sealed class BSPrim : PhysicsActor
 
     private List<OMV.Vector3> m_accumulatedForces = new List<OMV.Vector3>();
     public override void AddForce(OMV.Vector3 force, bool pushforce) {
+        AddForce(force, pushforce, false);
+    }
+    // Applying a force just adds this to the total force on the object.
+    public void AddForce(OMV.Vector3 force, bool pushforce, bool inTaintTime) {
         // for an object, doesn't matter if force is a pushforce or not
         if (force.IsFinite())
         {
@@ -624,56 +943,88 @@ public sealed class BSPrim : PhysicsActor
         }
         else
         {
-            m_log.WarnFormat("{0}: Got a NaN force applied to a Character", LogHeader);
+            m_log.WarnFormat("{0}: Got a NaN force applied to a prim. LocalID={1}", LogHeader, LocalID);
             return;
         }
-        _scene.TaintedObject("BSPrim.AddForce", delegate()
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.AddForce", delegate()
         {
             OMV.Vector3 fSum = OMV.Vector3.Zero;
             lock (m_accumulatedForces)
             {
+                // Sum the accumulated additional forces for one big force to apply once.
                 foreach (OMV.Vector3 v in m_accumulatedForces)
                 {
                     fSum += v;
                 }
                 m_accumulatedForces.Clear();
             }
-            // DetailLog("{0},BSPrim.AddObjectForce,taint,force={1}", LocalID, _force);
-            BulletSimAPI.AddObjectForce2(Body.Ptr, fSum);
+            DetailLog("{0},BSPrim.AddForce,taint,force={1}", LocalID, fSum);
+            if (fSum != OMV.Vector3.Zero)
+                BulletSimAPI.ApplyCentralForce2(PhysBody.ptr, fSum);
         });
     }
 
-    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);
+    // An impulse force is scaled by the mass of the object.
+    public void ApplyForceImpulse(OMV.Vector3 impulse, bool inTaintTime)
+    {
+        OMV.Vector3 applyImpulse = impulse;
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ApplyForceImpulse", delegate()
+        {
+            DetailLog("{0},BSPrim.ApplyForceImpulse,taint,tImpulse={1}", LocalID, applyImpulse);
+            BulletSimAPI.ApplyCentralImpulse2(PhysBody.ptr, applyImpulse);
+        });
     }
-    public override void SetMomentum(OMV.Vector3 momentum) { 
-        // DetailLog("{0},BSPrim.SetMomentum,call,mom={1}", LocalID, momentum);
+
+    private List<OMV.Vector3> m_accumulatedAngularForces = new List<OMV.Vector3>();
+    public override void AddAngularForce(OMV.Vector3 force, bool pushforce) {
+        AddAngularForce(force, pushforce, false);
     }
-    public override void SubscribeEvents(int ms) { 
-        _subscribedEventsMs = ms;
-        if (ms > 0)
+    public void AddAngularForce(OMV.Vector3 force, bool pushforce, bool inTaintTime)
+    {
+        if (force.IsFinite())
         {
-            // make sure first collision happens
-            _nextCollisionOkTime = Util.EnvironmentTickCount() - _subscribedEventsMs;
-
-            Scene.TaintedObject("BSPrim.SubscribeEvents", delegate()
-            {
-                BulletSimAPI.AddToCollisionFlags2(Body.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
-            });
+            // _force += force;
+            lock (m_accumulatedAngularForces)
+                m_accumulatedAngularForces.Add(new OMV.Vector3(force));
         }
-    }
-    public override void UnSubscribeEvents() { 
-        _subscribedEventsMs = 0;
-        Scene.TaintedObject("BSPrim.UnSubscribeEvents", delegate()
+        else
+        {
+            m_log.WarnFormat("{0}: Got a NaN force applied to a prim. LocalID={1}", LogHeader, LocalID);
+            return;
+        }
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.AddAngularForce", delegate()
         {
-            BulletSimAPI.RemoveFromCollisionFlags2(Body.Ptr, CollisionFlags.BS_SUBSCRIBE_COLLISION_EVENTS);
+            OMV.Vector3 fSum = OMV.Vector3.Zero;
+            lock (m_accumulatedAngularForces)
+            {
+                // Sum the accumulated additional forces for one big force to apply once.
+                foreach (OMV.Vector3 v in m_accumulatedAngularForces)
+                {
+                    fSum += v;
+                }
+                m_accumulatedAngularForces.Clear();
+            }
+            DetailLog("{0},BSPrim.AddAngularForce,taint,aForce={1}", LocalID, fSum);
+            if (fSum != OMV.Vector3.Zero)
+            {
+                BulletSimAPI.ApplyTorque2(PhysBody.ptr, fSum);
+                _torque = fSum;
+            }
         });
     }
-    public override bool SubscribedEvents() { 
-        return (_subscribedEventsMs > 0);
+    // A torque impulse.
+    public void ApplyTorqueImpulse(OMV.Vector3 impulse, bool inTaintTime)
+    {
+        OMV.Vector3 applyImpulse = impulse;
+        PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ApplyTorqueImpulse", delegate()
+        {
+            BulletSimAPI.ApplyTorqueImpulse2(PhysBody.ptr, applyImpulse);
+        });
     }
 
+    public override void SetMomentum(OMV.Vector3 momentum) {
+        // DetailLog("{0},BSPrim.SetMomentum,call,mom={1}", LocalID, momentum);
+    }
     #region Mass Calculation
 
     private float CalculateMass()
@@ -682,19 +1033,19 @@ public sealed class BSPrim : PhysicsActor
         float tmp;
 
         float returnMass = 0;
-        float hollowAmount = (float)_pbs.ProfileHollow * 2.0e-5f;
-        float hollowVolume = hollowAmount * hollowAmount; 
-        
-        switch (_pbs.ProfileShape)
+        float hollowAmount = (float)BaseShape.ProfileHollow * 2.0e-5f;
+        float hollowVolume = hollowAmount * hollowAmount;
+
+        switch (BaseShape.ProfileShape)
         {
             case ProfileShape.Square:
                 // default box
 
-                if (_pbs.PathCurve == (byte)Extrusion.Straight)
+                if (BaseShape.PathCurve == (byte)Extrusion.Straight)
                     {
                     if (hollowAmount > 0.0)
                         {
-                        switch (_pbs.HollowShape)
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Square:
                             case HollowShape.Same:
@@ -718,19 +1069,19 @@ public sealed class BSPrim : PhysicsActor
                         }
                     }
 
-                else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
+                else if (BaseShape.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 *= 0.78539816339e-2f * (float)(200 - BaseShape.PathScaleX);
+                    tmp= 1.0f -2.0e-2f * (float)(200 - BaseShape.PathScaleY);
                     volume -= volume*tmp*tmp;
-                    
+
                     if (hollowAmount > 0.0)
                         {
                         hollowVolume *= hollowAmount;
-                        
-                        switch (_pbs.HollowShape)
+
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Square:
                             case HollowShape.Same:
@@ -755,13 +1106,13 @@ public sealed class BSPrim : PhysicsActor
 
             case ProfileShape.Circle:
 
-                if (_pbs.PathCurve == (byte)Extrusion.Straight)
+                if (BaseShape.PathCurve == (byte)Extrusion.Straight)
                     {
                     volume *= 0.78539816339f; // elipse base
 
                     if (hollowAmount > 0.0)
                         {
-                        switch (_pbs.HollowShape)
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Same:
                             case HollowShape.Circle:
@@ -783,19 +1134,19 @@ public sealed class BSPrim : PhysicsActor
                         }
                     }
 
-                else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
+                else if (BaseShape.PathCurve == (byte)Extrusion.Curve1)
                     {
-                    volume *= 0.61685027506808491367715568749226e-2f * (float)(200 - _pbs.PathScaleX);
-                    tmp = 1.0f - .02f * (float)(200 - _pbs.PathScaleY);
+                    volume *= 0.61685027506808491367715568749226e-2f * (float)(200 - BaseShape.PathScaleX);
+                    tmp = 1.0f - .02f * (float)(200 - BaseShape.PathScaleY);
                     volume *= (1.0f - tmp * tmp);
-                    
+
                     if (hollowAmount > 0.0)
                         {
 
                         // calculate the hollow volume by it's shape compared to the prim shape
                         hollowVolume *= hollowAmount;
 
-                        switch (_pbs.HollowShape)
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Same:
                             case HollowShape.Circle:
@@ -819,7 +1170,7 @@ public sealed class BSPrim : PhysicsActor
                 break;
 
             case ProfileShape.HalfCircle:
-                if (_pbs.PathCurve == (byte)Extrusion.Curve1)
+                if (BaseShape.PathCurve == (byte)Extrusion.Curve1)
                 {
                 volume *= 0.52359877559829887307710723054658f;
                 }
@@ -827,7 +1178,7 @@ public sealed class BSPrim : PhysicsActor
 
             case ProfileShape.EquilateralTriangle:
 
-                if (_pbs.PathCurve == (byte)Extrusion.Straight)
+                if (BaseShape.PathCurve == (byte)Extrusion.Straight)
                     {
                     volume *= 0.32475953f;
 
@@ -835,7 +1186,7 @@ public sealed class BSPrim : PhysicsActor
                         {
 
                         // calculate the hollow volume by it's shape compared to the prim shape
-                        switch (_pbs.HollowShape)
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Same:
                             case HollowShape.Triangle:
@@ -860,11 +1211,11 @@ public sealed class BSPrim : PhysicsActor
                         volume *= (1.0f - hollowVolume);
                         }
                     }
-                else if (_pbs.PathCurve == (byte)Extrusion.Curve1)
+                else if (BaseShape.PathCurve == (byte)Extrusion.Curve1)
                     {
                     volume *= 0.32475953f;
-                    volume *= 0.01f * (float)(200 - _pbs.PathScaleX);
-                    tmp = 1.0f - .02f * (float)(200 - _pbs.PathScaleY);
+                    volume *= 0.01f * (float)(200 - BaseShape.PathScaleX);
+                    tmp = 1.0f - .02f * (float)(200 - BaseShape.PathScaleY);
                     volume *= (1.0f - tmp * tmp);
 
                     if (hollowAmount > 0.0)
@@ -872,7 +1223,7 @@ public sealed class BSPrim : PhysicsActor
 
                         hollowVolume *= hollowAmount;
 
-                        switch (_pbs.HollowShape)
+                        switch (BaseShape.HollowShape)
                             {
                             case HollowShape.Same:
                             case HollowShape.Triangle:
@@ -912,26 +1263,26 @@ public sealed class BSPrim : PhysicsActor
         float profileBegin;
         float profileEnd;
 
-        if (_pbs.PathCurve == (byte)Extrusion.Straight || _pbs.PathCurve == (byte)Extrusion.Flexible)
+        if (BaseShape.PathCurve == (byte)Extrusion.Straight || BaseShape.PathCurve == (byte)Extrusion.Flexible)
             {
-            taperX1 = _pbs.PathScaleX * 0.01f;
+            taperX1 = BaseShape.PathScaleX * 0.01f;
             if (taperX1 > 1.0f)
                 taperX1 = 2.0f - taperX1;
             taperX = 1.0f - taperX1;
 
-            taperY1 = _pbs.PathScaleY * 0.01f;
+            taperY1 = BaseShape.PathScaleY * 0.01f;
             if (taperY1 > 1.0f)
                 taperY1 = 2.0f - taperY1;
             taperY = 1.0f - taperY1;
             }
         else
             {
-            taperX = _pbs.PathTaperX * 0.01f;
+            taperX = BaseShape.PathTaperX * 0.01f;
             if (taperX < 0.0f)
                 taperX = -taperX;
             taperX1 = 1.0f - taperX;
 
-            taperY = _pbs.PathTaperY * 0.01f;
+            taperY = BaseShape.PathTaperY * 0.01f;
             if (taperY < 0.0f)
                 taperY = -taperY;
             taperY1 = 1.0f - taperY;
@@ -941,20 +1292,18 @@ public sealed class BSPrim : PhysicsActor
 
         volume *= (taperX1 * taperY1 + 0.5f * (taperX1 * taperY + taperX * taperY1) + 0.3333333333f * taperX * taperY);
 
-        pathBegin = (float)_pbs.PathBegin * 2.0e-5f;
-        pathEnd = 1.0f - (float)_pbs.PathEnd * 2.0e-5f;
+        pathBegin = (float)BaseShape.PathBegin * 2.0e-5f;
+        pathEnd = 1.0f - (float)BaseShape.PathEnd * 2.0e-5f;
         volume *= (pathEnd - pathBegin);
 
         // this is crude aproximation
-        profileBegin = (float)_pbs.ProfileBegin * 2.0e-5f;
-        profileEnd = 1.0f - (float)_pbs.ProfileEnd * 2.0e-5f;
+        profileBegin = (float)BaseShape.ProfileBegin * 2.0e-5f;
+        profileEnd = 1.0f - (float)BaseShape.ProfileEnd * 2.0e-5f;
         volume *= (profileEnd - profileBegin);
 
         returnMass = _density * volume;
 
-        /*
-         * This change means each object keeps its own mass and the Mass property
-         * will return the sum if we're part of a linkset.
+        /* Comment out code that computes the mass of the linkset. That is done in the Linkset class.
         if (IsRootOfLinkset)
         {
             foreach (BSPrim prim in _childrenPrims)
@@ -967,296 +1316,49 @@ public sealed class BSPrim : PhysicsActor
         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
-    private bool CreateGeom(bool forceRebuild)
-    {
-        // the mesher thought this was too simple to mesh. Use a native Bullet collision shape.
-        bool ret = false;
-        if (!_scene.NeedsMeshing(_pbs))
-        {
-            if (_pbs.ProfileShape == ProfileShape.HalfCircle && _pbs.PathCurve == (byte)Extrusion.Curve1)
-            {
-                // if (_size.X == _size.Y && _size.Y == _size.Z && _size.X == _size.Z)
-                // {
-                    // m_log.DebugFormat("{0}: CreateGeom: Defaulting to sphere of size {1}", LogHeader, _size);
-                    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);
-                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;
-                }
-            }
-        }
-        else
-        {
-            if (IsPhysical)
-            {
-                if (forceRebuild || _hullKey == 0)
-                {
-                    // physical objects require a hull for interaction.
-                    // This will create the mesh if it doesn't already exist
-                    CreateGeomHull();
-                    ret = true;
-                }
-            }
-            else
-            {
-                if (forceRebuild || _meshKey == 0)
-                {
-                    // Static (non-physical) objects only need a mesh for bumping into
-                    CreateGeomMesh();
-                    ret = true;
-                }
-            }
-        }
-        return ret;
-    }
-
-    // No locking here because this is done when we know physics is not simulating
-    private void CreateGeomMesh()
-    {
-        float lod = _pbs.SculptEntry ? _scene.SculptLOD : _scene.MeshLOD;
-        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;
-
-        // 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);
-        // DetailLog("{0},BSPrim.CreateGeomMesh,done", LocalID);
-        return;
-    }
-
-    // No locking here because this is done when we know physics is not simulating
-    private void CreateGeomHull()
+    // Rebuild the geometry and object.
+    // This is called when the shape changes so we need to recreate the mesh/hull.
+    // Called at taint-time!!!
+    private void CreateGeomAndObject(bool forceRebuild)
     {
-        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;
-
-        // 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)
+        // If this prim is part of a linkset, we must remove and restore the physical
+        //    links if the body is rebuilt.
+        bool needToRestoreLinkset = false;
+        bool needToRestoreVehicle = false;
+
+        // Create the correct physical representation for this type of object.
+        // Updates PhysBody and PhysShape with the new information.
+        // Ignore 'forceRebuild'. This routine makes the right choices and changes of necessary.
+        // Returns 'true' if either the body or the shape was changed.
+        PhysicsScene.Shapes.GetBodyAndShape(false, PhysicsScene.World, this, null, delegate(BulletBody dBody)
         {
-            convVertices.Add(new float3(vv.X, vv.Y, vv.Z));
-        }
+            // Called if the current prim body is about to be destroyed.
+            // Remove all the physical dependencies on the old body.
+            // (Maybe someday make the changing of BSShape an event handled by BSLinkset.)
+            needToRestoreLinkset = Linkset.RemoveBodyDependencies(this);
+            needToRestoreVehicle = _vehicle.RemoveBodyDependencies(this);
+        });
 
-        // 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)
+        if (needToRestoreLinkset)
         {
-            totalVertices += 4;                         // add four for the vertex count and centroid
-            totalVertices += cr.HullIndices.Count * 3;  // we pass just triangles
+            // If physical body dependencies were removed, restore them
+            Linkset.RestoreBodyDependencies(this);
         }
-        float[] convHulls = new float[totalVertices];
-
-        convHulls[0] = (float)hullCount;
-        int jj = 1;
-        foreach (ConvexResult cr in _hulls)
+        if (needToRestoreVehicle)
         {
-            // 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;
-            }
+            // If physical body dependencies were removed, restore them
+            _vehicle.RestoreBodyDependencies(this);
         }
 
-        // 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;
-    }
-
-    // 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;
-    }
-
-    // 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.
-        Body = new BulletBody(LocalID, BulletSimAPI.GetBodyHandle2(_scene.World.Ptr, LocalID));
-
-        return ret;
-    }
-
-    // Copy prim's info into the BulletSim shape description structure
-    public void FillShapeInfo(out ShapeData shape)
-    {
-        shape.ID = _localID;
-        shape.Type = _shapeType;
-        shape.Position = _position;
-        shape.Rotation = _orientation;
-        shape.Velocity = _velocity;
-        shape.Scale = _scale;
-        shape.Mass = _isPhysical ? _mass : 0f;
-        shape.Buoyancy = _buoyancy;
-        shape.HullKey = _hullKey;
-        shape.MeshKey = _meshKey;
-        shape.Friction = _friction;
-        shape.Restitution = _restitution;
-        shape.Collidable = (!IsPhantom) ? ShapeData.numericTrue : ShapeData.numericFalse;
-        shape.Static = _isPhysical ? ShapeData.numericFalse : ShapeData.numericTrue;
-    }
-
-
-    // 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
-    private void RecreateGeomAndObject()
-    {
-        // m_log.DebugFormat("{0}: RecreateGeomAndObject. lID={1}", LogHeader, _localID);
-        if (CreateGeom(true))
-            CreateObject();
+        // Make sure the properties are set on the new object
+        UpdatePhysicalParameters();
         return;
     }
 
@@ -1277,7 +1379,7 @@ public sealed class BSPrim : PhysicsActor
     const float ACCELERATION_TOLERANCE = 0.01f;
     const float ROTATIONAL_VELOCITY_TOLERANCE = 0.01f;
 
-    public void UpdateProperties(EntityProperties entprop)
+    public override void UpdateProperties(EntityProperties entprop)
     {
         /*
         UpdatedProperties changed = 0;
@@ -1315,7 +1417,7 @@ public sealed class BSPrim : PhysicsActor
         if (changed != 0)
         {
             // Only update the position of single objects and linkset roots
-            if (this._parentPrim == null)
+            if (Linkset.IsRoot(this))
             {
                 base.RequestPhysicsterseUpdate();
             }
@@ -1325,78 +1427,46 @@ public sealed class BSPrim : PhysicsActor
         // Don't check for damping here -- it's done in BulletSim and SceneObjectPart.
 
         // Updates only for individual prims and for the root object of a linkset.
-        if (_linkset.IsRoot(this))
+        if (Linkset.IsRoot(this))
         {
-            // Assign to the local variables so the normal set action does not happen
+            // Assign directly to the local variables so the normal set action does not happen
             _position = entprop.Position;
             _orientation = entprop.Rotation;
             _velocity = entprop.Velocity;
             _acceleration = entprop.Acceleration;
             _rotationalVelocity = entprop.RotationalVelocity;
 
-            // m_log.DebugFormat("{0}: RequestTerseUpdate. id={1}, ch={2}, pos={3}, rot={4}, vel={5}, acc={6}, rvel={7}", 
-            //         LogHeader, LocalID, changed, _position, _orientation, _velocity, _acceleration, _rotationalVelocity);
-            // DetailLog("{0},BSPrim.UpdateProperties,call,pos={1},orient={2},vel={3},accel={4},rotVel={5}",
-            //         LocalID, _position, _orientation, _velocity, _acceleration, _rotationalVelocity);
+            // The sanity check can change the velocity and/or position.
+            if (PositionSanityCheck(true))
+            {
+                entprop.Position = _position;
+                entprop.Velocity = _velocity;
+            }
+
+            // remember the current and last set values
+            LastEntityProperties = CurrentEntityProperties;
+            CurrentEntityProperties = entprop;
+
+            OMV.Vector3 direction = OMV.Vector3.UnitX * _orientation;
+            DetailLog("{0},BSPrim.UpdateProperties,call,pos={1},orient={2},dir={3},vel={4},rotVel={5}",
+                    LocalID, _position, _orientation, direction, _velocity, _rotationalVelocity);
+
+            // BulletSimAPI.DumpRigidBody2(PhysicsScene.World.ptr, BSBody.ptr);   // DEBUG DEBUG DEBUG
 
             base.RequestPhysicsterseUpdate();
         }
             /*
         else
         {
-            // For debugging, we also report the movement of children
+            // For debugging, 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
-    CollisionEventUpdate collisionCollection;
-    public void Collide(uint collidingWith, ActorTypes type, OMV.Vector3 contactPoint, OMV.Vector3 contactNormal, float pentrationDepth)
-    {
-        // m_log.DebugFormat("{0}: Collide: ms={1}, id={2}, with={3}", LogHeader, _subscribedEventsMs, LocalID, collidingWith);
-
-        // The following lines make IsColliding() and IsCollidingGround() work
-        _collidingStep = _scene.SimulationStep;
-        if (collidingWith == BSScene.TERRAIN_ID || collidingWith == BSScene.GROUNDPLANE_ID)
-        {
-            _collidingGroundStep = _scene.SimulationStep;
-        }
-
-        // DetailLog("{0},BSPrim.Collison,call,with={1}", LocalID, collidingWith);
-
-        // if someone is subscribed to collision events....
-        if (_subscribedEventsMs != 0) {
-            // 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));
-            }
-        }
-    }
-
-    // The scene is telling us it's time to pass our collected collisions into the simulator
-    public 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);
+        // The linkset implimentation might want to know about this.
+        Linkset.UpdateProperties(this);
     }
 }
 }