7 files changed, 1171 insertions, 488 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
new file mode 100755
index 0000000..fbb9e21
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
@@ -0,0 +1,115 @@
+/*
+ * 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
+{
+
+public class BSConstraint : IDisposable
+{
+    private BulletSim m_world;
+    private BulletBody m_body1;
+    private BulletBody m_body2;
+    private BulletConstraint m_constraint;
+    private bool m_enabled = false;
+
+    public BSConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,
+                    Vector3 frame1, Quaternion frame1rot,
+                    Vector3 frame2, Quaternion frame2rot
+        )
+    {
+        m_world = world;
+        m_body1 = obj1;
+        m_body2 = obj2;
+        m_constraint = new BulletConstraint(BulletSimAPI.CreateConstraint2(m_world.Ptr, m_body1.Ptr, m_body2.Ptr,
+                            frame1, frame1rot,
+                            frame2, frame2rot));
+        m_enabled = true;
+    }
+
+    public void Dispose()
+    {
+        if (m_enabled)
+        {
+            // BulletSimAPI.RemoveConstraint(m_world.ID, m_body1.ID, m_body2.ID);
+            BulletSimAPI.DestroyConstraint2(m_world.Ptr, m_constraint.Ptr);
+            m_enabled = false;
+        }
+    }
+
+    public BulletBody Body1 { get { return m_body1; } }
+    public BulletBody Body2 { get { return m_body2; } }
+
+    public bool SetLinearLimits(Vector3 low, Vector3 high)
+    {
+        bool ret = false;
+        if (m_enabled)
+            ret = BulletSimAPI.SetLinearLimits2(m_constraint.Ptr, low, high);
+        return ret;
+    }
+
+    public bool SetAngularLimits(Vector3 low, Vector3 high)
+    {
+        bool ret = false;
+        if (m_enabled)
+            ret = BulletSimAPI.SetAngularLimits2(m_constraint.Ptr, low, high);
+        return ret;
+    }
+
+    public bool UseFrameOffset(bool useOffset)
+    {
+        bool ret = false;
+        float onOff = useOffset ? ConfigurationParameters.numericTrue : ConfigurationParameters.numericFalse;
+        if (m_enabled)
+            ret = BulletSimAPI.UseFrameOffset2(m_constraint.Ptr, onOff);
+        return ret;
+    }
+
+    public bool TranslationalLimitMotor(bool enable, float targetVelocity, float maxMotorForce)
+    {
+        bool ret = false;
+        float onOff = enable ? ConfigurationParameters.numericTrue : ConfigurationParameters.numericFalse;
+        if (m_enabled)
+            ret = BulletSimAPI.TranslationalLimitMotor2(m_constraint.Ptr, onOff, targetVelocity, maxMotorForce);
+        return ret;
+    }
+
+    public bool CalculateTransforms()
+    {
+        bool ret = false;
+        if (m_enabled)
+        {
+            BulletSimAPI.CalculateTransforms2(m_constraint.Ptr);
+            ret = true;
+        }
+        return ret;
+    }
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSConstraintCollection.cs b/OpenSim/Region/Physics/BulletSPlugin/BSConstraintCollection.cs
new file mode 100755
index 0000000..a2650fb
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSConstraintCollection.cs
@@ -0,0 +1,178 @@
+/*
+ * 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 log4net;
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+
+public class BSConstraintCollection : IDisposable
+{
+    // private static readonly ILog m_log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
+    // private static readonly string LogHeader = "[CONSTRAINT COLLECTION]";
+
+    delegate bool ConstraintAction(BSConstraint constrain);
+
+    private List<BSConstraint> m_constraints;
+    private BulletSim m_world;
+
+    public BSConstraintCollection(BulletSim world)
+    {
+        m_world = world;
+        m_constraints = new List<BSConstraint>();
+    }
+
+    public void Dispose()
+    {
+        this.Clear();
+    }
+
+    public void Clear()
+    {
+        foreach (BSConstraint cons in m_constraints)
+        {
+            cons.Dispose();
+        }
+        m_constraints.Clear();
+    }
+
+    public BSConstraint CreateConstraint(BulletSim world, BulletBody obj1, BulletBody obj2,
+                    Vector3 frame1, Quaternion frame1rot,
+                    Vector3 frame2, Quaternion frame2rot)
+    {
+        BSConstraint constrain = new BSConstraint(world, obj1, obj2, frame1, frame1rot, frame2, frame2rot);
+
+        this.AddConstraint(constrain);
+        return constrain;
+    }
+
+    public bool AddConstraint(BSConstraint cons)
+    {
+        // There is only one constraint between any bodies. Remove any old just to make sure.
+        RemoveAndDestroyConstraint(cons.Body1, cons.Body2);
+
+        m_constraints.Add(cons);
+
+        return true;
+    }
+
+    // Get the constraint between two bodies. There can be only one the way we're using them.
+    public bool TryGetConstraint(BulletBody body1, BulletBody body2, out BSConstraint returnConstraint)
+    {
+        bool found = false;
+        BSConstraint foundConstraint = null;
+
+        uint lookingID1 = body1.ID;
+        uint lookingID2 = body2.ID;
+        ForEachConstraint(delegate(BSConstraint constrain)
+        {
+            if ((constrain.Body1.ID == lookingID1 && constrain.Body2.ID == lookingID2)
+                || (constrain.Body1.ID == lookingID2 && constrain.Body2.ID == lookingID1))
+            {
+                foundConstraint = constrain;
+                found = true;
+            }
+            return found;
+        });
+        returnConstraint = foundConstraint;
+        return found;
+    }
+
+    public bool RemoveAndDestroyConstraint(BulletBody body1, BulletBody body2)
+    {
+        // return BulletSimAPI.RemoveConstraint(m_world.ID, obj1.ID, obj2.ID);
+
+        bool ret = false;
+        BSConstraint constrain;
+
+        if (this.TryGetConstraint(body1, body2, out constrain))
+        {
+            // remove the constraint from our collection
+            m_constraints.Remove(constrain);
+            // tell the engine that all its structures need to be freed
+            constrain.Dispose();
+            // we destroyed something
+            ret = true;
+        }
+
+        return ret;
+    }
+
+    public bool RemoveAndDestroyConstraint(BulletBody body1)
+    {
+        // return BulletSimAPI.RemoveConstraintByID(m_world.ID, obj.ID);
+
+        List<BSConstraint> toRemove = new List<BSConstraint>();
+        uint lookingID = body1.ID;
+        ForEachConstraint(delegate(BSConstraint constrain)
+        {
+            if (constrain.Body1.ID == lookingID || constrain.Body2.ID == lookingID)
+            {
+                toRemove.Add(constrain);
+            }
+            return false;
+        });
+        lock (m_constraints)
+        {
+            foreach (BSConstraint constrain in toRemove)
+            {
+                m_constraints.Remove(constrain);
+                constrain.Dispose();
+            }
+        }
+        return (toRemove.Count > 0);
+    }
+
+    public bool RecalculateAllConstraints()
+    {
+        foreach (BSConstraint constrain in m_constraints)
+        {
+            constrain.CalculateTransforms();
+        }
+        return true;
+    }
+
+    // Lock the constraint list and loop through it.
+    // The constraint action returns 'true' if it wants the loop aborted.
+    private void ForEachConstraint(ConstraintAction action)
+    {
+        lock (m_constraints)
+        {
+            foreach (BSConstraint constrain in m_constraints)
+            {
+                if (action(constrain))
+                    break;
+            }
+        }
+    }
+
+
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
new file mode 100755
index 0000000..3bc2100
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
@@ -0,0 +1,308 @@
+/*
+ * 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;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+public class BSLinkset
+{
+    private static string LogHeader = "[BULLETSIM LINKSET]";
+
+    private BSPrim m_linksetRoot;
+    public BSPrim Root { get { return m_linksetRoot; } }
+
+    private BSScene m_scene;
+
+    private List<BSPrim> m_children;
+
+    // We lock the diddling of linkset classes to prevent any badness.
+    // This locks the modification of the instances of this class. Changes
+    //    to the physical representation is done via the tainting mechenism.
+    private object m_linksetActivityLock = new Object();
+
+    // 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 
+        {
+            m_mass = ComputeLinksetMass();
+            return m_mass;
+        }
+    }
+
+    public OMV.Vector3 CenterOfMass
+    {
+        get { return ComputeLinksetCenterOfMass(); }
+    }
+
+    public OMV.Vector3 GeometricCenter
+    {
+        get { return ComputeLinksetGeometricCenter(); }
+    }
+
+    public BSLinkset(BSScene scene, BSPrim parent)
+    {
+        // A simple linkset of one (no children)
+        m_scene = scene;
+        m_linksetRoot = parent;
+        m_children = new List<BSPrim>();
+        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 it's membership.
+    public BSLinkset AddMeToLinkset(BSPrim child, BSPrim parent)
+    {
+        lock (m_linksetActivityLock)
+        {
+            parent.Linkset.AddChildToLinkset(child);
+        }
+        return parent.Linkset;
+    }
+
+    public BSLinkset RemoveMeFromLinkset(BSPrim 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.
+                    RemoveChildFromLinkset(m_children[0]);
+                }
+                m_children.Clear(); // just to make sure
+            }
+            else
+            {
+                // Just removing a child from an existing linkset
+                RemoveChildFromLinkset(child);
+            }
+        }
+
+        // The child is down to a linkset of just itself
+        return new BSLinkset(m_scene, child);
+    }
+
+    // An existing linkset had one of its members rebuilt or something.
+    // Undo all the physical linking and rebuild the physical linkset.
+    public bool RefreshLinkset(BSPrim requestor)
+    {
+        return true;
+    }
+
+
+    // Return 'true' if the passed object is the root object of this linkset
+    public bool IsRoot(BSPrim requestor)
+    {
+        return (requestor.LocalID == m_linksetRoot.LocalID);
+    }
+
+    // Return 'true' if this linkset has any children (more than the root member)
+    public bool HasAnyChildren { get { return (m_children.Count > 0); } }
+
+    // Return 'true' if this child is in this linkset
+    public bool HasChild(BSPrim child)
+    {
+        bool ret = false;
+        foreach (BSPrim bp in m_children)
+        {
+            if (child.LocalID == bp.LocalID)
+            {
+                ret = true;
+                break;
+            }
+        }
+        return ret;
+    }
+
+    private float ComputeLinksetMass()
+    {
+        float mass = m_linksetRoot.MassRaw;
+        foreach (BSPrim 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;
+
+        foreach (BSPrim bp in m_children)
+        {
+            com += bp.Position * bp.MassRaw;
+            totalMass += bp.MassRaw;
+        }
+        com /= totalMass;
+
+        return com;
+    }
+
+    private OMV.Vector3 ComputeLinksetGeometricCenter()
+    {
+        OMV.Vector3 com = m_linksetRoot.Position;
+
+        foreach (BSPrim bp in m_children)
+        {
+            com += bp.Position * bp.MassRaw;
+        }
+        com /= m_children.Count + 1;
+
+        return com;
+    }
+
+    // I am the root of a linkset and a new child is being added
+    public void AddChildToLinkset(BSPrim pchild)
+    {
+        BSPrim child = pchild;
+        if (!HasChild(child))
+        {
+            m_children.Add(child);
+
+            m_scene.TaintedObject(delegate()
+            {
+                DebugLog("{0}: AddChildToLinkset: adding child {1} to {2}", LogHeader, child.LocalID, m_linksetRoot.LocalID);
+                DetailLog("{0},AddChildToLinkset,child={1}", m_linksetRoot.LocalID, pchild.LocalID);
+                PhysicallyLinkAChildToRoot(pchild);     // build the physical binding between me and the child
+            });
+        }
+        return;
+    }
+
+    // I am the root of a linkset and one of my children is being removed.
+    // Safe to call even if the child is not really in my linkset.
+    public void RemoveChildFromLinkset(BSPrim pchild)
+    {
+        BSPrim child = pchild;
+
+        if (m_children.Remove(child))
+        {
+            m_scene.TaintedObject(delegate()
+            {
+                DebugLog("{0}: RemoveChildFromLinkset: Removing constraint to {1}", LogHeader, child.LocalID);
+                DetailLog("{0},RemoveChildFromLinkset,child={1}", m_linksetRoot.LocalID, pchild.LocalID);
+
+                if (m_children.Count == 0)
+                {
+                    // if the linkset is empty, make sure all linkages have been removed
+                    PhysicallyUnlinkAllChildrenFromRoot();
+                }
+                else
+                {
+                    PhysicallyUnlinkAChildFromRoot(pchild);
+                }
+            });
+        }
+        else
+        {
+            // This will happen if we remove the root of the linkset first. Non-fatal occurance.
+            // m_scene.Logger.ErrorFormat("{0}: Asked to remove child from linkset that was not in linkset", LogHeader);
+        }
+        return;
+    }
+
+    // Create a constraint between me (root of linkset) and the passed prim (the child).
+    // Called at taint time!
+    private void PhysicallyLinkAChildToRoot(BSPrim childPrim)
+    {
+        // Zero motion for children so they don't interpolate
+        childPrim.ZeroMotion();
+
+        // relative position normalized to the root prim
+        OMV.Quaternion invThisOrientation = OMV.Quaternion.Inverse(m_linksetRoot.Orientation);
+        OMV.Vector3 childRelativePosition = (childPrim.Position - m_linksetRoot.Position) * invThisOrientation;
+
+        // relative rotation of the child to the parent
+        OMV.Quaternion childRelativeRotation = invThisOrientation * childPrim.Orientation;
+
+        // create a constraint that allows no freedom of movement between the two objects
+        // http://bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=4818
+        // DebugLog("{0}: CreateLinkset: Adding a constraint between root prim {1} and child prim {2}", LogHeader, LocalID, childPrim.LocalID);
+        DetailLog("{0},LinkAChildToMe,taint,root={1},child={2}", m_linksetRoot.LocalID, m_linksetRoot.LocalID, childPrim.LocalID);
+        BSConstraint constrain = m_scene.Constraints.CreateConstraint(
+                        m_scene.World, m_linksetRoot.Body, childPrim.Body,
+                        childRelativePosition,
+                        childRelativeRotation,
+                        OMV.Vector3.Zero,
+                        OMV.Quaternion.Identity);
+        constrain.SetLinearLimits(OMV.Vector3.Zero, OMV.Vector3.Zero);
+        constrain.SetAngularLimits(OMV.Vector3.Zero, OMV.Vector3.Zero);
+
+        // tweek the constraint to increase stability
+        constrain.UseFrameOffset(m_scene.BoolNumeric(m_scene.Params.linkConstraintUseFrameOffset));
+        constrain.TranslationalLimitMotor(m_scene.BoolNumeric(m_scene.Params.linkConstraintEnableTransMotor),
+                        m_scene.Params.linkConstraintTransMotorMaxVel,
+                        m_scene.Params.linkConstraintTransMotorMaxForce);
+
+    }
+
+    // Remove linkage between myself and a particular child
+    // Called at taint time!
+    private void PhysicallyUnlinkAChildFromRoot(BSPrim childPrim)
+    {
+        DebugLog("{0}: PhysicallyUnlinkAChildFromRoot: RemoveConstraint between root prim {1} and child prim {2}", 
+                    LogHeader, m_linksetRoot.LocalID, childPrim.LocalID);
+        DetailLog("{0},PhysicallyUnlinkAChildFromRoot,taint,root={1},child={2}", m_linksetRoot.LocalID, m_linksetRoot.LocalID, childPrim.LocalID);
+        // BulletSimAPI.RemoveConstraint(_scene.WorldID, LocalID, childPrim.LocalID);
+        m_scene.Constraints.RemoveAndDestroyConstraint(m_linksetRoot.Body, childPrim.Body);
+    }
+
+    // Remove linkage between myself and any possible children I might have
+    // Called at taint time!
+    private void PhysicallyUnlinkAllChildrenFromRoot()
+    {
+        // DebugLog("{0}: PhysicallyUnlinkAllChildren:", LogHeader);
+        DetailLog("{0},PhysicallyUnlinkAllChildren,taint", m_linksetRoot.LocalID);
+        m_scene.Constraints.RemoveAndDestroyConstraint(m_linksetRoot.Body);
+        // BulletSimAPI.RemoveConstraintByID(_scene.WorldID, LocalID);
+    }
+
+    // Invoke the detailed logger and output something if it's enabled.
+    private void DebugLog(string msg, params Object[] args)
+    {
+        m_scene.Logger.DebugFormat(msg, args);
+    }
+
+    // Invoke the detailed logger and output something if it's enabled.
+    private void DetailLog(string msg, params Object[] args)
+    {
+        m_scene.PhysicsLogging.Write(msg, args);
+    }
+
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index a19d6d7..7590d93 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -66,7 +66,7 @@ public sealed class BSPrim : PhysicsActor
     private bool _isSelected;
     private bool _isVolumeDetect;
     private OMV.Vector3 _position;
-    private float _mass;
+    private float _mass;    // the mass of this object
     private float _density;
     private OMV.Vector3 _force;
     private OMV.Vector3 _velocity;
@@ -89,14 +89,22 @@ public sealed class BSPrim : PhysicsActor
     private bool _kinematic;
     private float _buoyancy;
 
-    private BSPrim _parentPrim;
-    private List<BSPrim> _childrenPrims;
+    // 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; } }
+
     private BSDynamics _vehicle;
 
     private OMV.Vector3 _PIDTarget;
@@ -130,14 +138,18 @@ public sealed class BSPrim : PhysicsActor
         _friction = _scene.Params.defaultFriction; // TODO: compute based on object material
         _density = _scene.Params.defaultDensity; // TODO: compute based on object material
         _restitution = _scene.Params.defaultRestitution;
-        _parentPrim = null;     // not a child or a parent
+        _linkset = new BSLinkset(_scene, this);     // a linkset of one
         _vehicle = new BSDynamics(this);    // add vehicleness
-        _childrenPrims = new List<BSPrim>();
         _mass = CalculateMass();
         // do the actual object creation at taint time
         _scene.TaintedObject(delegate()
         {
             RecreateGeomAndObject();
+
+            // 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));
         });
     }
 
@@ -153,16 +165,8 @@ public sealed class BSPrim : PhysicsActor
 
         _scene.TaintedObject(delegate()
         {
-            // undo any dependance with/on other objects
-            if (_parentPrim != null)
-            {
-                // If I'm someone's child, tell them to forget about me.
-                _parentPrim.RemoveChildFromLinkset(this);
-                _parentPrim = null;
-            }
-
-            // make sure there are no possible children depending on me
-            UnlinkAllChildren();
+            // Undo any links between me and any other object
+            _linkset = _linkset.RemoveMeFromLinkset(this);
 
             // everything in the C# world will get garbage collected. Tell the C++ world to free stuff.
             BulletSimAPI.DestroyObject(_scene.WorldID, LocalID);
@@ -179,7 +183,7 @@ public sealed class BSPrim : PhysicsActor
             _scene.TaintedObject(delegate()
             {
                 _mass = CalculateMass();   // changing size changes the mass
-                BulletSimAPI.SetObjectScaleMass(_scene.WorldID, _localID, _scale, Mass, IsPhysical);
+                BulletSimAPI.SetObjectScaleMass(_scene.WorldID, _localID, _scale, (IsPhysical ? _mass : 0f), IsPhysical);
                 RecreateGeomAndObject();
             });
         } 
@@ -218,32 +222,8 @@ public sealed class BSPrim : PhysicsActor
         BSPrim parent = obj as BSPrim;
         DebugLog("{0}: link {1}/{2} to {3}", LogHeader, _avName, _localID, obj.LocalID);
         DetailLog("{0},link,parent={1}", LocalID, obj.LocalID);
-        // TODO: decide if this parent checking needs to happen at taint time
-        if (_parentPrim == null)
-        {
-            if (parent != null)
-            {
-                // I don't have a parent so I am joining a linkset
-                parent.AddChildToLinkset(this);
-            }
-        }
-        else
-        {
-            // I already have a parent, is parenting changing?
-            if (parent != _parentPrim)
-            {
-                if (parent == null)
-                {
-                    // we are being removed from a linkset
-                    _parentPrim.RemoveChildFromLinkset(this);
-                }
-                else
-                {
-                    // asking to reparent a prim should not happen
-                    m_log.ErrorFormat("{0}: link(): Reparenting a prim. ", LogHeader);
-                }
-            }
-        }
+
+        _linkset = _linkset.AddMeToLinkset(this, parent);
         return; 
     }
 
@@ -252,92 +232,28 @@ public sealed class BSPrim : PhysicsActor
         // 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, 
-                (_parentPrim==null ? "NULL" : _parentPrim._avName+"/"+_parentPrim.LocalID.ToString()));
-        DetailLog("{0},delink,parent={1}", LocalID, (_parentPrim==null ? "NULL" : _parentPrim.LocalID.ToString()));
-        if (_parentPrim != null)
-        {
-            _parentPrim.RemoveChildFromLinkset(this);
-        }
-        return; 
-    }
-
-    // I am the root of a linkset and a new child is being added
-    public void AddChildToLinkset(BSPrim pchild)
-    {
-        BSPrim child = pchild;
-        _scene.TaintedObject(delegate()
-        {
-            if (!_childrenPrims.Contains(child))
-            {
-                DebugLog("{0}: AddChildToLinkset: adding child {1} to {2}", LogHeader, child.LocalID, this.LocalID);
-                DetailLog("{0},AddChildToLinkset,child={1}", LocalID, pchild.LocalID);
-                _childrenPrims.Add(child);
-                child._parentPrim = this;    // the child has gained a parent
-                // RecreateGeomAndObject();    // rebuild my shape with the new child added
-                LinkAChildToMe(pchild);     // build the physical binding between me and the child
-
-                _mass = CalculateMass();
-            }
-        });
-        return;
-    }
-
-    // I am the root of a linkset and one of my children is being removed.
-    // Safe to call even if the child is not really in my linkset.
-    public void RemoveChildFromLinkset(BSPrim pchild)
-    {
-        BSPrim child = pchild;
-        _scene.TaintedObject(delegate()
-        {
-            if (_childrenPrims.Contains(child))
-            {
-                DebugLog("{0}: RemoveChildFromLinkset: Removing constraint to {1}", LogHeader, child.LocalID);
-                DetailLog("{0},RemoveChildFromLinkset,child={1}", LocalID, pchild.LocalID);
-                _childrenPrims.Remove(child);
-                child._parentPrim = null;    // the child has lost its parent
-                if (_childrenPrims.Count == 0)
-                {
-                    // if the linkset is empty, make sure all linkages have been removed
-                    UnlinkAllChildren();
-                }
-                else
-                {
-                    // RecreateGeomAndObject();    // rebuild my shape with the child removed
-                    UnlinkAChildFromMe(pchild);
-                }
-
-                _mass = CalculateMass();
-            }
-            else
-            {
-                m_log.ErrorFormat("{0}: Asked to remove child from linkset that was not in linkset");
-            }
-        });
-        return;
-    }
+                            _linkset.Root._avName+"/"+_linkset.Root.LocalID.ToString());
+        DetailLog("{0},delink,parent={1}", LocalID, _linkset.Root.LocalID.ToString());
 
-    // return true if we are the root of a linkset (there are children to manage)
-    public bool IsRootOfLinkset
-    {
-        get { return (_parentPrim == null && _childrenPrims.Count != 0); }
+        _linkset.RemoveMeFromLinkset(this);
+        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!
-    private void ZeroMotion()
+    public void ZeroMotion()
     {
         _velocity = OMV.Vector3.Zero;
         _acceleration = OMV.Vector3.Zero;
         _rotationalVelocity = OMV.Vector3.Zero;
 
         // Zero some other properties directly into the physics engine
-        IntPtr obj = BulletSimAPI.GetBodyHandleWorldID2(_scene.WorldID, LocalID);
-        BulletSimAPI.SetVelocity2(obj, OMV.Vector3.Zero);
-        BulletSimAPI.SetAngularVelocity2(obj, OMV.Vector3.Zero);
-        BulletSimAPI.SetInterpolation2(obj, OMV.Vector3.Zero, OMV.Vector3.Zero);
-        BulletSimAPI.ClearForces2(obj);
+        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);
     }
 
     public override void LockAngularMotion(OMV.Vector3 axis)
@@ -348,9 +264,10 @@ public sealed class BSPrim : PhysicsActor
 
     public override OMV.Vector3 Position { 
         get { 
-            // child prims move around based on their parent. Need to get the latest location
-            if (_parentPrim != null)
+            if (!_linkset.IsRoot(this))
+                // child prims move around based on their parent. Need to get the latest location
                 _position = BulletSimAPI.GetObjectPosition(_scene.WorldID, _localID);
+
             // don't do the GetObjectPosition for root elements because this function is called a zillion times
             // _position = BulletSimAPI.GetObjectPosition(_scene.WorldID, _localID);
             return _position; 
@@ -366,16 +283,31 @@ public sealed class BSPrim : PhysicsActor
         } 
     }
 
-    // Return the effective mass of the object. Non-physical objects do not have mass.
-    public override float Mass { 
-        get {
-            if (IsPhysical)
-                return _mass;
-            else
-                return 0f;
+    // 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;
         }
     }
 
+    // used when we only want this prim's mass and not the linkset thing
+    public float MassRaw { get { return _mass; } }
+
+    // Is this used?
+    public override OMV.Vector3 CenterOfMass
+    {
+        get { return _linkset.CenterOfMass; }
+    }
+
+    // Is this used?
+    public override OMV.Vector3 GeometricCenter
+    {
+        get { return _linkset.GeometricCenter; }
+    }
+
     public override OMV.Vector3 Force { 
         get { return _force; } 
         set {
@@ -383,7 +315,8 @@ public sealed class BSPrim : PhysicsActor
             _scene.TaintedObject(delegate()
             {
                 DetailLog("{0},SetForce,taint,force={1}", LocalID, _force);
-                BulletSimAPI.SetObjectForce(_scene.WorldID, _localID, _force);
+                // BulletSimAPI.SetObjectForce(_scene.WorldID, _localID, _force);
+                BulletSimAPI.SetObjectForce2(Body.Ptr, _force);
             });
         } 
     }
@@ -407,8 +340,7 @@ public sealed class BSPrim : PhysicsActor
                     _scene.TaintedObject(delegate()
                     {
                         // Tell the physics engine to clear state
-                        IntPtr obj = BulletSimAPI.GetBodyHandleWorldID2(_scene.WorldID, LocalID);
-                        BulletSimAPI.ClearForces2(obj);
+                        BulletSimAPI.ClearForces2(this.Body.Ptr);
                     });
 
                     // make it so the scene will call us each tick to do vehicle things
@@ -420,7 +352,6 @@ public sealed class BSPrim : PhysicsActor
     }
     public override void VehicleFloatParam(int param, float value) 
     {
-        m_log.DebugFormat("{0} VehicleFloatParam. {1} <= {2}", LogHeader, param, value);
         _scene.TaintedObject(delegate()
         {
             _vehicle.ProcessFloatVehicleParam((Vehicle)param, value, _scene.LastSimulatedTimestep);
@@ -428,7 +359,6 @@ public sealed class BSPrim : PhysicsActor
     }
     public override void VehicleVectorParam(int param, OMV.Vector3 value) 
     {
-        m_log.DebugFormat("{0} VehicleVectorParam. {1} <= {2}", LogHeader, param, value);
         _scene.TaintedObject(delegate()
         {
             _vehicle.ProcessVectorVehicleParam((Vehicle)param, value, _scene.LastSimulatedTimestep);
@@ -436,7 +366,6 @@ public sealed class BSPrim : PhysicsActor
     }
     public override void VehicleRotationParam(int param, OMV.Quaternion rotation) 
     {
-        m_log.DebugFormat("{0} VehicleRotationParam. {1} <= {2}", LogHeader, param, rotation);
         _scene.TaintedObject(delegate()
         {
             _vehicle.ProcessRotationVehicleParam((Vehicle)param, rotation);
@@ -444,7 +373,6 @@ public sealed class BSPrim : PhysicsActor
     }
     public override void VehicleFlags(int param, bool remove) 
     {
-        m_log.DebugFormat("{0} VehicleFlags. {1}. Remove={2}", LogHeader, param, remove);
         _scene.TaintedObject(delegate()
         {
             _vehicle.ProcessVehicleFlags(param, remove);
@@ -470,8 +398,6 @@ public sealed class BSPrim : PhysicsActor
         return; 
     }
 
-    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 {
@@ -500,9 +426,9 @@ public sealed class BSPrim : PhysicsActor
     }
     public override OMV.Quaternion Orientation { 
         get {
-            if (_parentPrim != null)
+            if (!_linkset.IsRoot(this))
             {
-                // children move around because tied to parent. Get a fresh value.
+                // Children move around because tied to parent. Get a fresh value.
                 _orientation = BulletSimAPI.GetObjectOrientation(_scene.WorldID, LocalID);
             }
             return _orientation;
@@ -552,14 +478,16 @@ public sealed class BSPrim : PhysicsActor
     private void SetObjectDynamic()
     {
         // m_log.DebugFormat("{0}: ID={1}, SetObjectDynamic: IsStatic={2}, IsSolid={3}", LogHeader, _localID, IsStatic, IsSolid);
-        // non-physical things work best with a mass of zero
-        if (!IsStatic)
-        {
-            _mass = CalculateMass();
-            RecreateGeomAndObject();
-        }
-        DetailLog("{0},SetObjectDynamic,taint,static={1},solid={2},mass={3}", LocalID, IsStatic, IsSolid, Mass);
-        BulletSimAPI.SetObjectProperties(_scene.WorldID, LocalID, IsStatic, IsSolid, SubscribedEvents(), Mass);
+
+        RecreateGeomAndObject();
+
+        float mass = _mass;
+        // Bullet wants static objects have a mass of zero
+        if (IsStatic) 
+            mass = 0f;
+
+        DetailLog("{0},SetObjectDynamic,taint,static={1},solid={2},mass={3}", LocalID, IsStatic, IsSolid, mass);
+        BulletSimAPI.SetObjectProperties(_scene.WorldID, LocalID, IsStatic, IsSolid, SubscribedEvents(), mass);
     }
 
     // prims don't fly
@@ -1001,6 +929,9 @@ public sealed class BSPrim : PhysicsActor
 
         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.
         if (IsRootOfLinkset)
         {
             foreach (BSPrim prim in _childrenPrims)
@@ -1008,6 +939,7 @@ public sealed class BSPrim : PhysicsActor
                 returnMass += prim.CalculateMass();
             }
         }
+         */
 
         if (returnMass <= 0)
             returnMass = 0.0001f;
@@ -1023,9 +955,11 @@ public sealed class BSPrim : PhysicsActor
     // 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
-    private void CreateGeom(bool forceRebuild)
+    // 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)
@@ -1033,18 +967,26 @@ public sealed class BSPrim : PhysicsActor
                 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);
-                    _shapeType = ShapeData.PhysicsShapeType.SHAPE_SPHERE;
-                    DetailLog("{0},CreateGeom,sphere", LocalID);
-                    // Bullet native objects are scaled by the Bullet engine so pass the size in
-                    _scale = _size;
+                    if (_shapeType != ShapeData.PhysicsShapeType.SHAPE_SPHERE)
+                    {
+                        DetailLog("{0},CreateGeom,sphere", LocalID);
+                        _shapeType = ShapeData.PhysicsShapeType.SHAPE_SPHERE;
+                        ret = true;
+                        // Bullet native objects are scaled by the Bullet engine so pass the size in
+                        _scale = _size;
+                    }
                 }
             }
             else
             {
                 // m_log.DebugFormat("{0}: CreateGeom: Defaulting to box. lid={1}, size={2}", LogHeader, LocalID, _size);
-                DetailLog("{0},CreateGeom,box", LocalID);
-                _shapeType = ShapeData.PhysicsShapeType.SHAPE_BOX;
-                _scale = _size;
+                if (_shapeType != ShapeData.PhysicsShapeType.SHAPE_BOX)
+                {
+                    DetailLog("{0},CreateGeom,box", LocalID);
+                    _shapeType = ShapeData.PhysicsShapeType.SHAPE_BOX;
+                    ret = true;
+                    _scale = _size;
+                }
             }
         }
         else
@@ -1056,6 +998,7 @@ public sealed class BSPrim : PhysicsActor
                     // physical objects require a hull for interaction.
                     // This will create the mesh if it doesn't already exist
                     CreateGeomHull();
+                    ret = true;
                 }
             }
             else
@@ -1064,9 +1007,11 @@ public sealed class BSPrim : PhysicsActor
                 {
                     // 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
@@ -1251,20 +1196,18 @@ public sealed class BSPrim : PhysicsActor
     // No locking here because this is done when the physics engine is not simulating
     private void CreateObject()
     {
-        if (IsRootOfLinkset)
-        {
-            // Create a linkset around this object
-            CreateLinkset();
-        }
-        else
-        {
-            // simple object
-            // 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);
-            BulletSimAPI.CreateObject(_scene.WorldID, shape);
-        }
+        // 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);
+        BulletSimAPI.CreateObject(_scene.WorldID, shape);
+        // the CreateObject() may have recreated the rigid body. Make sure we have the latest.
+        m_body.Ptr = BulletSimAPI.GetBodyHandle2(_scene.World.Ptr, LocalID);
+
+        // The root object could have been recreated. Make sure everything linksety is up to date.
+        _linkset.RefreshLinkset(this);
     }
 
     // Copy prim's info into the BulletSim shape description structure
@@ -1276,7 +1219,7 @@ public sealed class BSPrim : PhysicsActor
         shape.Rotation = _orientation;
         shape.Velocity = _velocity;
         shape.Scale = _scale;
-        shape.Mass = Mass;
+        shape.Mass = _isPhysical ? _mass : 0f;
         shape.Buoyancy = _buoyancy;
         shape.HullKey = _hullKey;
         shape.MeshKey = _meshKey;
@@ -1286,72 +1229,6 @@ public sealed class BSPrim : PhysicsActor
         shape.Static = _isPhysical ? ShapeData.numericFalse : ShapeData.numericTrue;
     }
 
-    #region Linkset creation and destruction
-
-    // Create the linkset by putting constraints between the objects of the set so they cannot move
-    // relative to each other.
-    void CreateLinkset()
-    {
-        DebugLog("{0}: CreateLinkset. Root prim={1}, prims={2}", LogHeader, LocalID, _childrenPrims.Count+1);
-
-        // remove any constraints that might be in place
-        DebugLog("{0}: CreateLinkset: RemoveConstraints between me and any children", LogHeader, LocalID);
-        BulletSimAPI.RemoveConstraintByID(_scene.WorldID, LocalID);
-
-        // create constraints between the root prim and each of the children
-        foreach (BSPrim prim in _childrenPrims)
-        {
-            LinkAChildToMe(prim);
-        }
-    }
-
-    // Create a constraint between me (root of linkset) and the passed prim (the child).
-    // Called at taint time!
-    private void LinkAChildToMe(BSPrim childPrim)
-    {
-        // Zero motion for children so they don't interpolate
-        childPrim.ZeroMotion();
-
-        // relative position normalized to the root prim
-        OMV.Quaternion invThisOrientation = OMV.Quaternion.Inverse(this._orientation);
-        OMV.Vector3 childRelativePosition = (childPrim._position - this._position) * invThisOrientation;
-
-        // relative rotation of the child to the parent
-        OMV.Quaternion childRelativeRotation = invThisOrientation * childPrim._orientation;
-
-        // create a constraint that allows no freedom of movement between the two objects
-        // http://bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=4818
-        DebugLog("{0}: CreateLinkset: Adding a constraint between root prim {1} and child prim {2}", LogHeader, LocalID, childPrim.LocalID);
-        DetailLog("{0},LinkAChildToMe,taint,root={1},child={2}", LocalID, LocalID, childPrim.LocalID);
-        BulletSimAPI.AddConstraint(_scene.WorldID, LocalID, childPrim.LocalID, 
-            childRelativePosition,
-            childRelativeRotation,
-            OMV.Vector3.Zero,
-            OMV.Quaternion.Identity,
-            OMV.Vector3.Zero, OMV.Vector3.Zero,
-            OMV.Vector3.Zero, OMV.Vector3.Zero);
-    }
-
-    // Remove linkage between myself and a particular child
-    // Called at taint time!
-    private void UnlinkAChildFromMe(BSPrim childPrim)
-    {
-        DebugLog("{0}: UnlinkAChildFromMe: RemoveConstraint between root prim {1} and child prim {2}", 
-                    LogHeader, LocalID, childPrim.LocalID);
-        DetailLog("{0},UnlinkAChildFromMe,taint,root={1},child={2}", LocalID, LocalID, childPrim.LocalID);
-        BulletSimAPI.RemoveConstraint(_scene.WorldID, LocalID, childPrim.LocalID);
-    }
-
-    // Remove linkage between myself and any possible children I might have
-    // Called at taint time!
-    private void UnlinkAllChildren()
-    {
-        DebugLog("{0}: UnlinkAllChildren:", LogHeader);
-        DetailLog("{0},UnlinkAllChildren,taint", LocalID);
-        BulletSimAPI.RemoveConstraintByID(_scene.WorldID, LocalID);
-    }
-
-    #endregion // Linkset creation and destruction
 
     // Rebuild the geometry and object.
     // This is called when the shape changes so we need to recreate the mesh/hull.
@@ -1429,7 +1306,7 @@ 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 (_parentPrim == null)
+        if (_linkset.IsRoot(this))
         {
             // Assign to the local variables so the normal set action does not happen
             _position = entprop.Position;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
index 7cc3fe3..c6d622b 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
@@ -73,7 +73,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     private static readonly ILog m_log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
     private static readonly string LogHeader = "[BULLETS SCENE]";
 
-    private void DebugLog(string mm, params Object[] xx) { if (shouldDebugLog) m_log.DebugFormat(mm, xx); }
+    public void DebugLog(string mm, params Object[] xx) { if (shouldDebugLog) m_log.DebugFormat(mm, xx); }
 
     public string BulletSimVersion = "?";
 
@@ -87,6 +87,9 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     private uint m_worldID;
     public uint WorldID { get { return m_worldID; } }
 
+    // let my minuions use my logger
+    public ILog Logger { get { return m_log; } }
+
     private bool m_initialized = false;
 
     private int m_detailedStatsStep = 0;
@@ -103,6 +106,17 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         get { return m_sculptLOD; }
     }
 
+    private BulletSim m_worldSim;
+    public BulletSim World
+    {
+        get { return m_worldSim; }
+    }
+    private BSConstraintCollection m_constraintCollection;
+    public BSConstraintCollection Constraints
+    { 
+        get { return m_constraintCollection; }
+    }
+
     private int m_maxSubSteps;
     private float m_fixedTimeStep;
     private long m_simulationStep = 0;
@@ -229,6 +243,11 @@ public class BSScene : PhysicsScene, IPhysicsParameters
                                         m_maxCollisionsPerFrame, m_collisionArrayPinnedHandle.AddrOfPinnedObject(),
                                         m_maxUpdatesPerFrame, m_updateArrayPinnedHandle.AddrOfPinnedObject());
 
+        // Initialization to support the transition to a new API which puts most of the logic
+        //   into the C# code so it is easier to modify and add to.
+        m_worldSim = new BulletSim(m_worldID, BulletSimAPI.GetSimHandle2(m_worldID));
+        m_constraintCollection = new BSConstraintCollection(World);
+
         m_initialized = true;
     }
 
@@ -237,116 +256,17 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     private void GetInitialParameterValues(IConfigSource config)
     {
         ConfigurationParameters parms = new ConfigurationParameters();
+        m_params[0] = parms;
 
-        _meshSculptedPrim = true;           // mesh sculpted prims
-        _forceSimplePrimMeshing = false;    // use complex meshing if called for
-
-        m_meshLOD = 8f;
-        m_sculptLOD = 32f;
-
-        shouldDebugLog = false;
-        m_detailedStatsStep = 0;            // disabled
-
-        m_maxSubSteps = 10;
-        m_fixedTimeStep = 1f / 60f;
-        m_maxCollisionsPerFrame = 2048;
-        m_maxUpdatesPerFrame = 2048;
-        m_maximumObjectMass = 10000.01f;
-
-        PID_D = 2200f;
-        PID_P = 900f;
-
-        parms.defaultFriction = 0.5f;
-        parms.defaultDensity = 10.000006836f; // Aluminum g/cm3
-        parms.defaultRestitution = 0f;
-        parms.collisionMargin = 0.0f;
-        parms.gravity = -9.80665f;
-
-        parms.linearDamping = 0.0f;
-        parms.angularDamping = 0.0f;
-        parms.deactivationTime = 0.2f;
-        parms.linearSleepingThreshold = 0.8f;
-        parms.angularSleepingThreshold = 1.0f;
-        parms.ccdMotionThreshold = 0.0f;    // set to zero to disable
-        parms.ccdSweptSphereRadius = 0.0f;
-        parms.contactProcessingThreshold = 0.1f;
-
-        parms.terrainFriction = 0.5f;
-        parms.terrainHitFraction = 0.8f;
-        parms.terrainRestitution = 0f;
-        parms.avatarFriction = 0.5f;
-        parms.avatarRestitution = 0.0f;
-        parms.avatarDensity = 60f;
-        parms.avatarCapsuleRadius = 0.37f;
-        parms.avatarCapsuleHeight = 1.5f; // 2.140599f
-        parms.avatarContactProcessingThreshold = 0.1f;
-
-        parms.maxPersistantManifoldPoolSize = 0f;
-        parms.shouldDisableContactPoolDynamicAllocation = ConfigurationParameters.numericTrue;
-        parms.shouldForceUpdateAllAabbs = ConfigurationParameters.numericFalse;
-        parms.shouldRandomizeSolverOrder = ConfigurationParameters.numericFalse;
-        parms.shouldSplitSimulationIslands = ConfigurationParameters.numericFalse;
-        parms.shouldEnableFrictionCaching = ConfigurationParameters.numericFalse;
-        parms.numberOfSolverIterations = 0f;    // means use default
+        SetParameterDefaultValues();
 
         if (config != null)
         {
             // If there are specifications in the ini file, use those values
-            // WHEN ADDING OR UPDATING THIS SECTION, BE SURE TO UPDATE OpenSimDefaults.ini
-            // ALSO REMEMBER TO UPDATE THE RUNTIME SETTING OF THE PARAMETERS.
             IConfig pConfig = config.Configs["BulletSim"];
             if (pConfig != null)
             {
-                _meshSculptedPrim = pConfig.GetBoolean("MeshSculptedPrim", _meshSculptedPrim);
-                _forceSimplePrimMeshing = pConfig.GetBoolean("ForceSimplePrimMeshing", _forceSimplePrimMeshing);
-
-                shouldDebugLog = pConfig.GetBoolean("ShouldDebugLog", shouldDebugLog);
-                m_detailedStatsStep = pConfig.GetInt("DetailedStatsStep", m_detailedStatsStep);
-
-                m_meshLOD = pConfig.GetFloat("MeshLevelOfDetail", m_meshLOD);
-                m_sculptLOD = pConfig.GetFloat("SculptLevelOfDetail", m_sculptLOD);
-
-                m_maxSubSteps = pConfig.GetInt("MaxSubSteps", m_maxSubSteps);
-                m_fixedTimeStep = pConfig.GetFloat("FixedTimeStep", m_fixedTimeStep);
-                m_maxCollisionsPerFrame = pConfig.GetInt("MaxCollisionsPerFrame", m_maxCollisionsPerFrame);
-                m_maxUpdatesPerFrame = pConfig.GetInt("MaxUpdatesPerFrame", m_maxUpdatesPerFrame);
-                m_maximumObjectMass = pConfig.GetFloat("MaxObjectMass", m_maximumObjectMass);
-
-                PID_D = pConfig.GetFloat("PIDDerivative", PID_D);
-                PID_P = pConfig.GetFloat("PIDProportional", PID_P);
-
-                parms.defaultFriction = pConfig.GetFloat("DefaultFriction", parms.defaultFriction);
-                parms.defaultDensity = pConfig.GetFloat("DefaultDensity", parms.defaultDensity);
-                parms.defaultRestitution = pConfig.GetFloat("DefaultRestitution", parms.defaultRestitution);
-                parms.collisionMargin = pConfig.GetFloat("CollisionMargin", parms.collisionMargin);
-                parms.gravity = pConfig.GetFloat("Gravity", parms.gravity);
-
-                parms.linearDamping = pConfig.GetFloat("LinearDamping", parms.linearDamping);
-                parms.angularDamping = pConfig.GetFloat("AngularDamping", parms.angularDamping);
-                parms.deactivationTime = pConfig.GetFloat("DeactivationTime", parms.deactivationTime);
-                parms.linearSleepingThreshold = pConfig.GetFloat("LinearSleepingThreshold", parms.linearSleepingThreshold);
-                parms.angularSleepingThreshold = pConfig.GetFloat("AngularSleepingThreshold", parms.angularSleepingThreshold);
-                parms.ccdMotionThreshold = pConfig.GetFloat("CcdMotionThreshold", parms.ccdMotionThreshold);
-                parms.ccdSweptSphereRadius = pConfig.GetFloat("CcdSweptSphereRadius", parms.ccdSweptSphereRadius);
-                parms.contactProcessingThreshold = pConfig.GetFloat("ContactProcessingThreshold", parms.contactProcessingThreshold);
-
-                parms.terrainFriction = pConfig.GetFloat("TerrainFriction", parms.terrainFriction);
-                parms.terrainHitFraction = pConfig.GetFloat("TerrainHitFraction", parms.terrainHitFraction);
-                parms.terrainRestitution = pConfig.GetFloat("TerrainRestitution", parms.terrainRestitution);
-                parms.avatarFriction = pConfig.GetFloat("AvatarFriction", parms.avatarFriction);
-                parms.avatarRestitution = pConfig.GetFloat("AvatarRestitution", parms.avatarRestitution);
-                parms.avatarDensity = pConfig.GetFloat("AvatarDensity", parms.avatarDensity);
-                parms.avatarCapsuleRadius = pConfig.GetFloat("AvatarCapsuleRadius", parms.avatarCapsuleRadius);
-                parms.avatarCapsuleHeight = pConfig.GetFloat("AvatarCapsuleHeight", parms.avatarCapsuleHeight);
-                parms.avatarContactProcessingThreshold = pConfig.GetFloat("AvatarContactProcessingThreshold", parms.avatarContactProcessingThreshold);
-
-                parms.maxPersistantManifoldPoolSize = pConfig.GetFloat("MaxPersistantManifoldPoolSize", parms.maxPersistantManifoldPoolSize);
-                parms.shouldDisableContactPoolDynamicAllocation = ParamBoolean(pConfig, "ShouldDisableContactPoolDynamicAllocation", parms.shouldDisableContactPoolDynamicAllocation);
-                    parms.shouldForceUpdateAllAabbs = ParamBoolean(pConfig, "ShouldForceUpdateAllAabbs", parms.shouldForceUpdateAllAabbs);
-                    parms.shouldRandomizeSolverOrder = ParamBoolean(pConfig, "ShouldRandomizeSolverOrder", parms.shouldRandomizeSolverOrder);
-                    parms.shouldSplitSimulationIslands = ParamBoolean(pConfig, "ShouldSplitSimulationIslands", parms.shouldSplitSimulationIslands);
-                    parms.shouldEnableFrictionCaching = ParamBoolean(pConfig, "ShouldEnableFrictionCaching", parms.shouldEnableFrictionCaching);
-                    parms.numberOfSolverIterations = pConfig.GetFloat("NumberOfSolverIterations", parms.numberOfSolverIterations);
+                SetParameterConfigurationValues(pConfig);
 
                 // Very detailed logging for physics debugging
                 m_physicsLoggingEnabled = pConfig.GetBoolean("PhysicsLoggingEnabled", false);
@@ -357,7 +277,6 @@ public class BSScene : PhysicsScene, IPhysicsParameters
                 m_vehicleLoggingEnabled = pConfig.GetBoolean("VehicleLoggingEnabled", false);
             }
         }
-        m_params[0] = parms;
     }
 
     // A helper function that handles a true/false parameter and returns the proper float number encoding
@@ -634,6 +553,12 @@ public class BSScene : PhysicsScene, IPhysicsParameters
         // make sure no stepping happens while we're deleting stuff
         m_initialized = false;
 
+        if (m_constraintCollection != null)
+        {
+            m_constraintCollection.Dispose();
+            m_constraintCollection = null;
+        }
+
         foreach (KeyValuePair<uint, BSCharacter> kvp in m_avatars)
         {
             kvp.Value.Destroy();
@@ -776,10 +701,12 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     }
 
     // The calls to the PhysicsActors can't directly call into the physics engine
-    // because it might be busy. We we delay changes to a known time.
+    // because it might be busy. We delay changes to a known time.
     // We rely on C#'s closure to save and restore the context for the delegate.
     public void TaintedObject(TaintCallback callback)
     {
+        if (!m_initialized) return;
+
         lock (_taintLock)
             _taintedObjects.Add(callback);
         return;
@@ -853,61 +780,371 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     }
     #endregion Vehicles
 
-    #region Runtime settable parameters
-    public static PhysParameterEntry[] SettableParameters = new PhysParameterEntry[]
+    #region Parameters
+
+    delegate void ParamUser(BSScene scene, IConfig conf, string paramName, float val);
+    delegate float ParamGet(BSScene scene);
+    delegate void ParamSet(BSScene scene, string paramName, uint localID, float val);
+
+    private struct ParameterDefn
+    {
+        public string name;
+        public string desc;
+        public float defaultValue;
+        public ParamUser userParam;
+        public ParamGet getter;
+        public ParamSet setter;
+        public ParameterDefn(string n, string d, float v, ParamUser u, ParamGet g, ParamSet s)
+        {
+            name = n;
+            desc = d;
+            defaultValue = v;
+            userParam = u;
+            getter = g;
+            setter = s;
+        }
+    }
+
+    // List of all of the externally visible parameters.
+    // For each parameter, this table maps a text name to getter and setters.
+    // 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.
+    //    -- a delegate for fetching the parameter from the ini file.
+    //          Should handle fetching the right type from the ini file and converting it.
+    //    -- a delegate for getting the value as a float
+    //    -- a delegate for setting the value from a float
+    //
+    // To add a new variable, it is best to find an existing definition and copy it.
+    private ParameterDefn[] ParameterDefinitions =
     {
-        new PhysParameterEntry("MeshLOD", "Level of detail to render meshes (32, 16, 8 or 4. 32=most detailed)"),
-        new PhysParameterEntry("SculptLOD", "Level of detail to render sculpties (32, 16, 8 or 4. 32=most detailed)"),
-        new PhysParameterEntry("MaxSubStep", "In simulation step, maximum number of substeps"),
-        new PhysParameterEntry("FixedTimeStep", "In simulation step, seconds of one substep (1/60)"),
-        new PhysParameterEntry("MaxObjectMass", "Maximum object mass (10000.01)"),
-        new PhysParameterEntry("DetailedStats", "Frames between outputting detailed phys stats. Zero is off"),
-
-        new PhysParameterEntry("DefaultFriction", "Friction factor used on new objects"),
-        new PhysParameterEntry("DefaultDensity", "Density for new objects" ),
-        new PhysParameterEntry("DefaultRestitution", "Bouncyness of an object" ),
-        // new PhysParameterEntry("CollisionMargin", "Margin around objects before collisions are calculated (must be zero!!)" ),
-        new PhysParameterEntry("Gravity", "Vertical force of gravity (negative means down)" ),
-
-        new PhysParameterEntry("LinearDamping", "Factor to damp linear movement per second (0.0 - 1.0)" ),
-        new PhysParameterEntry("AngularDamping", "Factor to damp angular movement per second (0.0 - 1.0)" ),
-        new PhysParameterEntry("DeactivationTime", "Seconds before considering an object potentially static" ),
-        new PhysParameterEntry("LinearSleepingThreshold", "Seconds to measure linear movement before considering static" ),
-        new PhysParameterEntry("AngularSleepingThreshold", "Seconds to measure angular movement before considering static" ),
-        new PhysParameterEntry("CcdMotionThreshold", "Continuious collision detection threshold (0 means no CCD)" ),
-        new PhysParameterEntry("CcdSweptSphereRadius", "Continuious collision detection test radius" ),
-        new PhysParameterEntry("ContactProcessingThreshold", "Distance between contacts before doing collision check" ),
-        // Can only change the following at initialization time. Change the INI file and reboot.
-            new PhysParameterEntry("MaxPersistantManifoldPoolSize", "Number of manifolds pooled (0 means default)"),
-            new PhysParameterEntry("ShouldDisableContactPoolDynamicAllocation", "Enable to allow large changes in object count"),
-            new PhysParameterEntry("ShouldForceUpdateAllAabbs", "Enable to recomputer AABBs every simulator step"),
-            new PhysParameterEntry("ShouldRandomizeSolverOrder", "Enable for slightly better stacking interaction"),
-            new PhysParameterEntry("ShouldSplitSimulationIslands", "Enable splitting active object scanning islands"),
-            new PhysParameterEntry("ShouldEnableFrictionCaching", "Enable friction computation caching"),
-            new PhysParameterEntry("NumberOfSolverIterations", "Number of internal iterations (0 means default)"),
-
-        new PhysParameterEntry("Friction", "Set friction parameter for a specific object" ),
-        new PhysParameterEntry("Restitution", "Set restitution parameter for a specific object" ),
-
-        new PhysParameterEntry("Friction", "Set friction parameter for a specific object" ),
-        new PhysParameterEntry("Restitution", "Set restitution parameter for a specific object" ),
-
-        new PhysParameterEntry("TerrainFriction", "Factor to reduce movement against terrain surface" ),
-        new PhysParameterEntry("TerrainHitFraction", "Distance to measure hit collisions" ),
-        new PhysParameterEntry("TerrainRestitution", "Bouncyness" ),
-        new PhysParameterEntry("AvatarFriction", "Factor to reduce movement against an avatar. Changed on avatar recreation." ),
-        new PhysParameterEntry("AvatarDensity", "Density of an avatar. Changed on avatar recreation." ),
-        new PhysParameterEntry("AvatarRestitution", "Bouncyness. Changed on avatar recreation." ),
-        new PhysParameterEntry("AvatarCapsuleRadius", "Radius of space around an avatar" ),
-        new PhysParameterEntry("AvatarCapsuleHeight", "Default height of space around avatar" ),
-            new PhysParameterEntry("AvatarContactProcessingThreshold", "Distance from capsule to check for collisions")
+        new ParameterDefn("MeshSculptedPrim", "Whether to create meshes for sculpties",
+            ConfigurationParameters.numericTrue,
+            (s,cf,p,v) => { s._meshSculptedPrim = cf.GetBoolean(p, s.BoolNumeric(v)); },
+            (s) => { return s.NumericBool(s._meshSculptedPrim); },
+            (s,p,l,v) => { s._meshSculptedPrim = s.BoolNumeric(v); } ),
+        new ParameterDefn("ForceSimplePrimMeshing", "If true, only use primitive meshes for objects",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s._forceSimplePrimMeshing = cf.GetBoolean(p, s.BoolNumeric(v)); },
+            (s) => { return s.NumericBool(s._forceSimplePrimMeshing); },
+            (s,p,l,v) => { s._forceSimplePrimMeshing = s.BoolNumeric(v); } ),
+
+        new ParameterDefn("MeshLOD", "Level of detail to render meshes (32, 16, 8 or 4. 32=most detailed)",
+            8f,
+            (s,cf,p,v) => { s.m_meshLOD = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_meshLOD; },
+            (s,p,l,v) => { s.m_meshLOD = (int)v; } ),
+        new ParameterDefn("SculptLOD", "Level of detail to render sculpties (32, 16, 8 or 4. 32=most detailed)",
+            32,
+            (s,cf,p,v) => { s.m_sculptLOD = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_sculptLOD; },
+            (s,p,l,v) => { s.m_sculptLOD = (int)v; } ),
+
+        new ParameterDefn("MaxSubStep", "In simulation step, maximum number of substeps",
+            10f,
+            (s,cf,p,v) => { s.m_maxSubSteps = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_maxSubSteps; },
+            (s,p,l,v) => { s.m_maxSubSteps = (int)v; } ),
+        new ParameterDefn("FixedTimeStep", "In simulation step, seconds of one substep (1/60)",
+            1f / 60f,
+            (s,cf,p,v) => { s.m_fixedTimeStep = cf.GetFloat(p, v); },
+            (s) => { return (float)s.m_fixedTimeStep; },
+            (s,p,l,v) => { s.m_fixedTimeStep = v; } ),
+        new ParameterDefn("MaxCollisionsPerFrame", "Max collisions returned at end of each frame",
+            2048f,
+            (s,cf,p,v) => { s.m_maxCollisionsPerFrame = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_maxCollisionsPerFrame; },
+            (s,p,l,v) => { s.m_maxCollisionsPerFrame = (int)v; } ),
+        new ParameterDefn("MaxUpdatesPerFrame", "Max updates returned at end of each frame",
+            8000f,
+            (s,cf,p,v) => { s.m_maxUpdatesPerFrame = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_maxUpdatesPerFrame; },
+            (s,p,l,v) => { s.m_maxUpdatesPerFrame = (int)v; } ),
+        new ParameterDefn("MaxObjectMass", "Maximum object mass (10000.01)",
+            10000.01f,
+            (s,cf,p,v) => { s.m_maximumObjectMass = cf.GetFloat(p, v); },
+            (s) => { return (float)s.m_maximumObjectMass; },
+            (s,p,l,v) => { s.m_maximumObjectMass = v; } ),
+
+        new ParameterDefn("PID_D", "Derivitive factor for motion smoothing",
+            2200f,
+            (s,cf,p,v) => { s.PID_D = cf.GetFloat(p, v); },
+            (s) => { return (float)s.PID_D; },
+            (s,p,l,v) => { s.PID_D = v; } ),
+        new ParameterDefn("PID_P", "Parameteric factor for motion smoothing",
+            900f,
+            (s,cf,p,v) => { s.PID_P = cf.GetFloat(p, v); },
+            (s) => { return (float)s.PID_P; },
+            (s,p,l,v) => { s.PID_P = v; } ),
+
+        new ParameterDefn("DefaultFriction", "Friction factor used on new objects",
+            0.5f,
+            (s,cf,p,v) => { s.m_params[0].defaultFriction = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].defaultFriction; },
+            (s,p,l,v) => { s.m_params[0].defaultFriction = v; } ),
+        new ParameterDefn("DefaultDensity", "Density for new objects" ,
+            10.000006836f,  // Aluminum g/cm3
+            (s,cf,p,v) => { s.m_params[0].defaultDensity = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].defaultDensity; },
+            (s,p,l,v) => { s.m_params[0].defaultDensity = v; } ),
+        new ParameterDefn("DefaultRestitution", "Bouncyness of an object" ,
+            0f,
+            (s,cf,p,v) => { s.m_params[0].defaultRestitution = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].defaultRestitution; },
+            (s,p,l,v) => { s.m_params[0].defaultRestitution = v; } ),
+        new ParameterDefn("CollisionMargin", "Margin around objects before collisions are calculated (must be zero!)",
+            0f,
+            (s,cf,p,v) => { s.m_params[0].collisionMargin = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].collisionMargin; },
+            (s,p,l,v) => { s.m_params[0].collisionMargin = v; } ),
+        new ParameterDefn("Gravity", "Vertical force of gravity (negative means down)",
+            -9.80665f,
+            (s,cf,p,v) => { s.m_params[0].gravity = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].gravity; },
+            (s,p,l,v) => { s.m_params[0].gravity = v; s.TaintedUpdateParameter(p,l,v); } ),
+
+
+        new ParameterDefn("LinearDamping", "Factor to damp linear movement per second (0.0 - 1.0)",
+            0f,
+            (s,cf,p,v) => { s.m_params[0].linearDamping = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].linearDamping; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].linearDamping, p, l, v); } ),
+        new ParameterDefn("AngularDamping", "Factor to damp angular movement per second (0.0 - 1.0)",
+            0f,
+            (s,cf,p,v) => { s.m_params[0].angularDamping = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].angularDamping; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].angularDamping, p, l, v); } ),
+        new ParameterDefn("DeactivationTime", "Seconds before considering an object potentially static",
+            0.2f,
+            (s,cf,p,v) => { s.m_params[0].deactivationTime = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].deactivationTime; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].deactivationTime, p, l, v); } ),
+        new ParameterDefn("LinearSleepingThreshold", "Seconds to measure linear movement before considering static",
+            0.8f,
+            (s,cf,p,v) => { s.m_params[0].linearSleepingThreshold = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].linearSleepingThreshold; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].linearSleepingThreshold, p, l, v); } ),
+        new ParameterDefn("AngularSleepingThreshold", "Seconds to measure angular movement before considering static",
+            1.0f,
+            (s,cf,p,v) => { s.m_params[0].angularSleepingThreshold = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].angularSleepingThreshold; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].angularSleepingThreshold, p, l, v); } ),
+        new ParameterDefn("CcdMotionThreshold", "Continuious collision detection threshold (0 means no CCD)" ,
+            0f,     // set to zero to disable
+            (s,cf,p,v) => { s.m_params[0].ccdMotionThreshold = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].ccdMotionThreshold; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].ccdMotionThreshold, p, l, v); } ),
+        new ParameterDefn("CcdSweptSphereRadius", "Continuious collision detection test radius" ,
+            0f,
+            (s,cf,p,v) => { s.m_params[0].ccdSweptSphereRadius = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].ccdSweptSphereRadius; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].ccdSweptSphereRadius, p, l, v); } ),
+        new ParameterDefn("ContactProcessingThreshold", "Distance between contacts before doing collision check" ,
+            0.1f,
+            (s,cf,p,v) => { s.m_params[0].contactProcessingThreshold = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].contactProcessingThreshold; },
+            (s,p,l,v) => { s.UpdateParameterPrims(ref s.m_params[0].contactProcessingThreshold, p, l, v); } ),
+
+        new ParameterDefn("TerrainFriction", "Factor to reduce movement against terrain surface" ,
+            0.5f,
+            (s,cf,p,v) => { s.m_params[0].terrainFriction = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].terrainFriction; },
+            (s,p,l,v) => { s.m_params[0].terrainFriction = v; s.TaintedUpdateParameter(p,l,v); } ),
+        new ParameterDefn("TerrainHitFraction", "Distance to measure hit collisions" ,
+            0.8f,
+            (s,cf,p,v) => { s.m_params[0].terrainHitFraction = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].terrainHitFraction; },
+            (s,p,l,v) => { s.m_params[0].terrainHitFraction = v; s.TaintedUpdateParameter(p,l,v); } ),
+        new ParameterDefn("TerrainRestitution", "Bouncyness" ,
+            0f,
+            (s,cf,p,v) => { s.m_params[0].terrainRestitution = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].terrainRestitution; },
+            (s,p,l,v) => { s.m_params[0].terrainRestitution = v; s.TaintedUpdateParameter(p,l,v); } ),
+        new ParameterDefn("AvatarFriction", "Factor to reduce movement against an avatar. Changed on avatar recreation.",
+            0.5f,
+            (s,cf,p,v) => { s.m_params[0].avatarFriction = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarFriction; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarFriction, p, l, v); } ),
+        new ParameterDefn("AvatarDensity", "Density of an avatar. Changed on avatar recreation.",
+            60f,
+            (s,cf,p,v) => { s.m_params[0].avatarDensity = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarDensity; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarDensity, p, l, v); } ),
+        new ParameterDefn("AvatarRestitution", "Bouncyness. Changed on avatar recreation.",
+            0f,
+            (s,cf,p,v) => { s.m_params[0].avatarRestitution = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarRestitution; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarRestitution, p, l, v); } ),
+        new ParameterDefn("AvatarCapsuleRadius", "Radius of space around an avatar",
+            0.37f,
+            (s,cf,p,v) => { s.m_params[0].avatarCapsuleRadius = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarCapsuleRadius; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarCapsuleRadius, p, l, v); } ),
+        new ParameterDefn("AvatarCapsuleHeight", "Default height of space around avatar",
+            1.5f,
+            (s,cf,p,v) => { s.m_params[0].avatarCapsuleHeight = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarCapsuleHeight; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarCapsuleHeight, p, l, v); } ),
+            new ParameterDefn("AvatarContactProcessingThreshold", "Distance from capsule to check for collisions",
+            0.1f,
+            (s,cf,p,v) => { s.m_params[0].avatarContactProcessingThreshold = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarContactProcessingThreshold; },
+            (s,p,l,v) => { s.UpdateParameterAvatars(ref s.m_params[0].avatarContactProcessingThreshold, p, l, v); } ),
+
+
+            new ParameterDefn("MaxPersistantManifoldPoolSize", "Number of manifolds pooled (0 means default)",
+            0f,     // zero to disable
+            (s,cf,p,v) => { s.m_params[0].maxPersistantManifoldPoolSize = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].maxPersistantManifoldPoolSize; },
+            (s,p,l,v) => { s.m_params[0].maxPersistantManifoldPoolSize = v; } ),
+            new ParameterDefn("ShouldDisableContactPoolDynamicAllocation", "Enable to allow large changes in object count",
+            ConfigurationParameters.numericTrue,
+            (s,cf,p,v) => { s.m_params[0].maxPersistantManifoldPoolSize = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (s) => { return s.m_params[0].shouldDisableContactPoolDynamicAllocation; },
+            (s,p,l,v) => { s.m_params[0].shouldDisableContactPoolDynamicAllocation = v; } ),
+            new ParameterDefn("ShouldForceUpdateAllAabbs", "Enable to recomputer AABBs every simulator step",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s.m_params[0].shouldForceUpdateAllAabbs = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (s) => { return s.m_params[0].shouldForceUpdateAllAabbs; },
+            (s,p,l,v) => { s.m_params[0].shouldForceUpdateAllAabbs = v; } ),
+            new ParameterDefn("ShouldRandomizeSolverOrder", "Enable for slightly better stacking interaction",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s.m_params[0].shouldRandomizeSolverOrder = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (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,
+            (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; } ),
+            new ParameterDefn("ShouldEnableFrictionCaching", "Enable friction computation caching",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s.m_params[0].shouldEnableFrictionCaching = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (s) => { return s.m_params[0].shouldEnableFrictionCaching; },
+            (s,p,l,v) => { s.m_params[0].shouldEnableFrictionCaching = v; } ),
+            new ParameterDefn("NumberOfSolverIterations", "Number of internal iterations (0 means default)",
+            0f,     // zero says use Bullet default
+            (s,cf,p,v) => { s.m_params[0].numberOfSolverIterations = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].numberOfSolverIterations; },
+            (s,p,l,v) => { s.m_params[0].numberOfSolverIterations = v; } ),
+
+            new ParameterDefn("LinkConstraintUseFrameOffset", "For linksets built with constraints, enable frame offsetFor linksets built with constraints, enable frame offset.",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s.m_params[0].linkConstraintUseFrameOffset = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (s) => { return s.m_params[0].linkConstraintUseFrameOffset; },
+            (s,p,l,v) => { s.m_params[0].linkConstraintUseFrameOffset = v; } ),
+            new ParameterDefn("LinkConstraintEnableTransMotor", "Whether to enable translational motor on linkset constraints",
+            ConfigurationParameters.numericTrue,
+            (s,cf,p,v) => { s.m_params[0].linkConstraintEnableTransMotor = s.NumericBool(cf.GetBoolean(p, s.BoolNumeric(v))); },
+            (s) => { return s.m_params[0].linkConstraintEnableTransMotor; },
+            (s,p,l,v) => { s.m_params[0].linkConstraintEnableTransMotor = v; } ),
+            new ParameterDefn("LinkConstraintTransMotorMaxVel", "Maximum velocity to be applied by translational motor in linkset constraints",
+            5.0f,
+            (s,cf,p,v) => { s.m_params[0].linkConstraintTransMotorMaxVel = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].linkConstraintTransMotorMaxVel; },
+            (s,p,l,v) => { s.m_params[0].linkConstraintTransMotorMaxVel = v; } ),
+            new ParameterDefn("LinkConstraintTransMotorMaxForce", "Maximum force to be applied by translational motor in linkset constraints",
+            0.1f,
+            (s,cf,p,v) => { s.m_params[0].linkConstraintTransMotorMaxForce = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].linkConstraintTransMotorMaxForce; },
+            (s,p,l,v) => { s.m_params[0].linkConstraintTransMotorMaxForce = v; } ),
+
+        new ParameterDefn("DetailedStats", "Frames between outputting detailed phys stats. (0 is off)",
+            0f,
+            (s,cf,p,v) => { s.m_detailedStatsStep = cf.GetInt(p, (int)v); },
+            (s) => { return (float)s.m_detailedStatsStep; },
+            (s,p,l,v) => { s.m_detailedStatsStep = (int)v; } ),
+        new ParameterDefn("ShouldDebugLog", "Enables detailed DEBUG log statements",
+            ConfigurationParameters.numericFalse,
+            (s,cf,p,v) => { s.shouldDebugLog = cf.GetBoolean(p, s.BoolNumeric(v)); },
+            (s) => { return s.NumericBool(s.shouldDebugLog); },
+            (s,p,l,v) => { s.shouldDebugLog = s.BoolNumeric(v); } ),
 
     };
 
+    // Convert a boolean to our numeric true and false values
+    public float NumericBool(bool b)
+    {
+        return (b ? ConfigurationParameters.numericTrue : ConfigurationParameters.numericFalse);
+    }
+
+    // Convert numeric true and false values to a boolean
+    public bool BoolNumeric(float b)
+    {
+        return (b == ConfigurationParameters.numericTrue ? true : false);
+    }
+
+    // Search through the parameter definitions and return the matching
+    //    ParameterDefn structure.
+    // Case does not matter as names are compared after converting to lower case.
+    // Returns 'false' if the parameter is not found.
+    private bool TryGetParameter(string paramName, out ParameterDefn defn)
+    {
+        bool ret = false;
+        ParameterDefn foundDefn = new ParameterDefn();
+        string pName = paramName.ToLower();
+
+        foreach (ParameterDefn parm in ParameterDefinitions)
+        {
+            if (pName == parm.name.ToLower())
+            {
+                foundDefn = parm;
+                ret = true;
+                break;
+            }
+        }
+        defn = foundDefn;
+        return ret;
+    }
+
+    // Pass through the settable parameters and set the default values
+    private void SetParameterDefaultValues()
+    {
+        foreach (ParameterDefn parm in ParameterDefinitions)
+        {
+            parm.setter(this, parm.name, PhysParameterEntry.APPLY_TO_NONE, parm.defaultValue);
+        }
+    }
+
+    // Get user set values out of the ini file.
+    private void SetParameterConfigurationValues(IConfig cfg)
+    {
+        foreach (ParameterDefn parm in ParameterDefinitions)
+        {
+            parm.userParam(this, cfg, parm.name, parm.defaultValue);
+        }
+    }
+
+    private PhysParameterEntry[] SettableParameters = new PhysParameterEntry[1];
+
+    private void BuildParameterTable()
+    {
+        if (SettableParameters.Length < ParameterDefinitions.Length)
+        {
+
+            List<PhysParameterEntry> entries = new List<PhysParameterEntry>();
+            for (int ii = 0; ii < ParameterDefinitions.Length; ii++)
+            {
+                ParameterDefn pd = ParameterDefinitions[ii];
+                entries.Add(new PhysParameterEntry(pd.name, pd.desc));
+            }
+
+            // make the list in alphabetical order for estetic reasons
+            entries.Sort(delegate(PhysParameterEntry ppe1, PhysParameterEntry ppe2)
+            {
+                return ppe1.name.CompareTo(ppe2.name);
+            });
+
+            SettableParameters = entries.ToArray();
+        }
+    }
+
+
     #region IPhysicsParameters
     // Get the list of parameters this physics engine supports
     public PhysParameterEntry[] GetParameterList()
     {
+        BuildParameterTable();
         return SettableParameters;
     }
 
@@ -919,63 +1156,18 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     //   value activated ('terrainFriction' for instance).
     public bool SetPhysicsParameter(string parm, float val, uint localID)
     {
-        bool ret = true;
-        string lparm = parm.ToLower();
-        switch (lparm)
+        bool ret = false;
+        ParameterDefn theParam;
+        if (TryGetParameter(parm, out theParam))
         {
-            case "detailedstats": m_detailedStatsStep = (int)val; break;
-
-            case "meshlod": m_meshLOD = (int)val; break;
-            case "sculptlod": m_sculptLOD = (int)val; break;
-            case "maxsubstep": m_maxSubSteps = (int)val; break;
-            case "fixedtimestep": m_fixedTimeStep = val; break;
-            case "maxobjectmass": m_maximumObjectMass = val; break;
-
-            case "defaultfriction": m_params[0].defaultFriction = val; break;
-            case "defaultdensity": m_params[0].defaultDensity = val; break;
-            case "defaultrestitution": m_params[0].defaultRestitution = val; break;
-            case "collisionmargin": m_params[0].collisionMargin = val; break;
-            case "gravity": m_params[0].gravity = val; TaintedUpdateParameter(lparm, localID, val); break;
-
-            case "lineardamping": UpdateParameterPrims(ref m_params[0].linearDamping, lparm, localID, val); break;
-            case "angulardamping": UpdateParameterPrims(ref m_params[0].angularDamping, lparm, localID, val); break;
-            case "deactivationtime": UpdateParameterPrims(ref m_params[0].deactivationTime, lparm, localID, val); break;
-            case "linearsleepingthreshold": UpdateParameterPrims(ref m_params[0].linearSleepingThreshold, lparm, localID, val); break;
-            case "angularsleepingthreshold": UpdateParameterPrims(ref m_params[0].angularDamping, lparm, localID, val); break;
-            case "ccdmotionthreshold": UpdateParameterPrims(ref m_params[0].ccdMotionThreshold, lparm, localID, val); break;
-            case "ccdsweptsphereradius": UpdateParameterPrims(ref m_params[0].ccdSweptSphereRadius, lparm, localID, val); break;
-            case "contactprocessingthreshold": UpdateParameterPrims(ref m_params[0].contactProcessingThreshold, lparm, localID, val); break;
-            // the following are used only at initialization time so setting them makes no sense
-                // case "maxPersistantmanifoldpoolSize": m_params[0].maxPersistantManifoldPoolSize = val; break;
-                // case "shoulddisablecontactpooldynamicallocation": m_params[0].shouldDisableContactPoolDynamicAllocation = val; break;
-                // case "shouldforceupdateallaabbs": m_params[0].shouldForceUpdateAllAabbs = val; break;
-                // case "shouldrandomizesolverorder": m_params[0].shouldRandomizeSolverOrder = val; break;
-                // case "shouldsplitsimulationislands": m_params[0].shouldSplitSimulationIslands = val; break;
-                // case "shouldenablefrictioncaching": m_params[0].shouldEnableFrictionCaching = val; break;
-                // case "numberofsolveriterations": m_params[0].numberOfSolverIterations = val; break;
-
-            case "friction": TaintedUpdateParameter(lparm, localID, val); break;
-            case "restitution": TaintedUpdateParameter(lparm, localID, val); break;
-
-            // set a terrain physical feature and cause terrain to be recalculated
-            case "terrainfriction": m_params[0].terrainFriction = val; TaintedUpdateParameter("terrain", 0, val); break;
-            case "terrainhitfraction": m_params[0].terrainHitFraction = val; TaintedUpdateParameter("terrain", 0, val); break;
-            case "terrainrestitution": m_params[0].terrainRestitution = val; TaintedUpdateParameter("terrain", 0, val); break;
-            // set an avatar physical feature and cause avatar(s) to be recalculated
-            case "avatarfriction": UpdateParameterAvatars(ref m_params[0].avatarFriction, "avatar", localID, val); break;
-            case "avatardensity": UpdateParameterAvatars(ref m_params[0].avatarDensity, "avatar", localID, val); break;
-            case "avatarrestitution": UpdateParameterAvatars(ref m_params[0].avatarRestitution, "avatar", localID, val); break;
-            case "avatarcapsuleradius": UpdateParameterAvatars(ref m_params[0].avatarCapsuleRadius, "avatar", localID, val); break;
-            case "avatarcapsuleheight": UpdateParameterAvatars(ref m_params[0].avatarCapsuleHeight, "avatar", localID, val); break;
-            case "avatarcontactprocessingthreshold": UpdateParameterAvatars(ref m_params[0].avatarContactProcessingThreshold, "avatar", localID, val); break;
-
-            default: ret = false; break;
+            theParam.setter(this, parm, localID, val);
+            ret = true;
         }
         return ret;
     }
 
     // check to see if we are updating a parameter for a particular or all of the prims
-    private void UpdateParameterPrims(ref float loc, string parm, uint localID, float val)
+    protected void UpdateParameterPrims(ref float loc, string parm, uint localID, float val)
     {
         List<uint> operateOn;
         lock (m_prims) operateOn = new List<uint>(m_prims.Keys);
@@ -983,7 +1175,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     }
 
     // check to see if we are updating a parameter for a particular or all of the avatars
-    private void UpdateParameterAvatars(ref float loc, string parm, uint localID, float val)
+    protected void UpdateParameterAvatars(ref float loc, string parm, uint localID, float val)
     {
         List<uint> operateOn;
         lock (m_avatars) operateOn = new List<uint>(m_avatars.Keys);
@@ -994,7 +1186,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     // If the local ID is APPLY_TO_NONE, just change the default value
     // If the localID is APPLY_TO_ALL change the default value and apply the new value to all the lIDs
     // If the localID is a specific object, apply the parameter change to only that object
-    private void UpdateParameterSet(List<uint> lIDs, ref float defaultLoc, string parm, uint localID, float val)
+    protected void UpdateParameterSet(List<uint> lIDs, ref float defaultLoc, string parm, uint localID, float val)
     {
         switch (localID)
         {
@@ -1021,7 +1213,7 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     }
 
     // schedule the actual updating of the paramter to when the phys engine is not busy
-    private void TaintedUpdateParameter(string parm, uint localID, float val)
+    protected void TaintedUpdateParameter(string parm, uint localID, float val)
     {
         uint xlocalID = localID;
         string xparm = parm.ToLower();
@@ -1036,50 +1228,12 @@ public class BSScene : PhysicsScene, IPhysicsParameters
     public bool GetPhysicsParameter(string parm, out float value)
     {
         float val = 0f;
-        bool ret = true;
-        switch (parm.ToLower())
+        bool ret = false;
+        ParameterDefn theParam;
+        if (TryGetParameter(parm, out theParam))
         {
-            case "detailedstats": val = (int)m_detailedStatsStep; break;
-            case "meshlod": val = (float)m_meshLOD; break;
-            case "sculptlod": val = (float)m_sculptLOD; break;
-            case "maxsubstep": val = (float)m_maxSubSteps; break;
-            case "fixedtimestep": val = m_fixedTimeStep; break;
-            case "maxobjectmass": val = m_maximumObjectMass; break;
-
-            case "defaultfriction": val = m_params[0].defaultFriction; break;
-            case "defaultdensity": val = m_params[0].defaultDensity; break;
-            case "defaultrestitution": val = m_params[0].defaultRestitution; break;
-            case "collisionmargin": val = m_params[0].collisionMargin; break;
-            case "gravity": val = m_params[0].gravity; break;
-
-            case "lineardamping": val = m_params[0].linearDamping; break;
-            case "angulardamping": val = m_params[0].angularDamping; break;
-            case "deactivationtime": val = m_params[0].deactivationTime; break;
-            case "linearsleepingthreshold": val = m_params[0].linearSleepingThreshold; break;
-            case "angularsleepingthreshold": val = m_params[0].angularDamping; break;
-            case "ccdmotionthreshold": val = m_params[0].ccdMotionThreshold; break;
-            case "ccdsweptsphereradius": val = m_params[0].ccdSweptSphereRadius; break;
-            case "contactprocessingthreshold": val = m_params[0].contactProcessingThreshold; break;
-                case "maxPersistantmanifoldpoolSize": val = m_params[0].maxPersistantManifoldPoolSize; break;
-                case "shoulddisablecontactpooldynamicallocation": val = m_params[0].shouldDisableContactPoolDynamicAllocation; break;
-                case "shouldforceupdateallaabbs": val = m_params[0].shouldForceUpdateAllAabbs; break;
-                case "shouldrandomizesolverorder": val = m_params[0].shouldRandomizeSolverOrder; break;
-                case "shouldsplitsimulationislands": val = m_params[0].shouldSplitSimulationIslands; break;
-                case "shouldenablefrictioncaching": val = m_params[0].shouldEnableFrictionCaching; break;
-                case "numberofsolveriterations": val = m_params[0].numberOfSolverIterations; break;
-
-            case "terrainfriction": val = m_params[0].terrainFriction; break;
-            case "terrainhitfraction": val = m_params[0].terrainHitFraction; break;
-            case "terrainrestitution": val = m_params[0].terrainRestitution; break;
-
-            case "avatarfriction": val = m_params[0].avatarFriction; break;
-            case "avatardensity": val = m_params[0].avatarDensity; break;
-            case "avatarrestitution": val = m_params[0].avatarRestitution; break;
-            case "avatarcapsuleradius": val = m_params[0].avatarCapsuleRadius; break;
-            case "avatarcapsuleheight": val = m_params[0].avatarCapsuleHeight; break;
-            case "avatarcontactprocessingthreshold": val = m_params[0].avatarContactProcessingThreshold; break;
-            default: ret = false; break;
-
+            val = theParam.getter(this);
+            ret = true;
         }
         value = val;
         return ret;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
index 54a8cfd..65e3145 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
@@ -32,6 +32,28 @@ using OpenMetaverse;
 
 namespace OpenSim.Region.Physics.BulletSPlugin {
 
+// Classes to allow some type checking for the API
+public struct BulletSim
+{
+    public BulletSim(uint id, IntPtr xx) { ID = id;  Ptr = xx; }
+    public IntPtr Ptr;
+    public uint ID;
+}
+
+public struct BulletBody
+{
+    public BulletBody(uint id, IntPtr xx) { ID = id;  Ptr = xx; }
+    public IntPtr Ptr;
+    public uint ID;
+}
+
+public struct BulletConstraint
+{
+    public BulletConstraint(IntPtr xx) { Ptr = xx; }
+    public IntPtr Ptr;
+}
+
+// ===============================================================================
 [StructLayout(LayoutKind.Sequential)]
 public struct ConvexHull 
 {
@@ -142,6 +164,11 @@ public struct ConfigurationParameters
         public float shouldEnableFrictionCaching;
         public float numberOfSolverIterations;
 
+    public float linkConstraintUseFrameOffset;
+    public float linkConstraintEnableTransMotor;
+    public float linkConstraintTransMotorMaxVel;
+    public float linkConstraintTransMotorMaxForce;
+
     public const float numericTrue = 1f;
     public const float numericFalse = 0f;
 }
@@ -162,6 +189,7 @@ public enum CollisionFlags : uint
     PHYSICAL_OBJECT               = 1 << 12,
 };
 
+// ===============================================================================
 static class BulletSimAPI {
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
@@ -211,6 +239,7 @@ public static extern bool DestroyMesh(uint worldID, System.UInt64 meshKey);
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern bool CreateObject(uint worldID, ShapeData shapeData);
 
+/*  Remove old functionality
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern void CreateLinkset(uint worldID, int objectCount, ShapeData[] shapeDatas);
 
@@ -225,6 +254,7 @@ public static extern bool RemoveConstraintByID(uint worldID, uint id1);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern bool RemoveConstraint(uint worldID, uint id1, uint id2);
+ */
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern Vector3 GetObjectPosition(uint WorldID, uint id);
@@ -350,8 +380,22 @@ public static extern IntPtr CreateObject2(IntPtr sim, ShapeData shapeData);
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern IntPtr CreateConstraint2(IntPtr sim, IntPtr obj1, IntPtr obj2,
                     Vector3 frame1loc, Quaternion frame1rot,
-                    Vector3 frame2loc, Quaternion frame2rot,
-                    Vector3 lowLinear, Vector3 hiLinear, Vector3 lowAngular, Vector3 hiAngular);
+                    Vector3 frame2loc, Quaternion frame2rot);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern bool SetLinearLimits2(IntPtr constrain, Vector3 low, Vector3 hi);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern bool SetAngularLimits2(IntPtr constrain, Vector3 low, Vector3 hi);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern bool UseFrameOffset2(IntPtr constrain, float enable);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern bool TranslationalLimitMotor2(IntPtr constrain, float enable, float targetVel, float maxMotorForce);
+
+[DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
+public static extern bool CalculateTransforms2(IntPtr constrain);
 
 [DllImport("BulletSim", CallingConvention = CallingConvention.Cdecl), SuppressUnmanagedCodeSecurity]
 public static extern bool DestroyConstraint2(IntPtr sim, IntPtr constrain);
diff --git a/OpenSim/Region/Physics/OdePlugin/OdeScene.cs b/OpenSim/Region/Physics/OdePlugin/OdeScene.cs
index 32e81e2..929b019 100644
--- a/OpenSim/Region/Physics/OdePlugin/OdeScene.cs
+++ b/OpenSim/Region/Physics/OdePlugin/OdeScene.cs
@@ -290,7 +290,6 @@ namespace OpenSim.Region.Physics.OdePlugin
 
         private readonly IntPtr contactgroup;
 
-        internal IntPtr LandGeom;
         internal IntPtr WaterGeom;
 
         private float nmTerrainContactFriction = 255.0f;
@@ -489,6 +488,8 @@ namespace OpenSim.Region.Physics.OdePlugin
         /// </summary>
         internal Object OdeLock = new Object();
 
+        private bool _worldInitialized = false;
+
         public IMesher mesher;
 
         private IConfigSource m_config;
@@ -875,6 +876,8 @@ namespace OpenSim.Region.Physics.OdePlugin
                     staticPrimspace[i, j] = IntPtr.Zero;
                 }
             }
+
+            _worldInitialized = true;
         }
 
 //        internal void waitForSpaceUnlock(IntPtr space)
@@ -1508,8 +1511,7 @@ namespace OpenSim.Region.Physics.OdePlugin
                 {
                     if (((Math.Abs(contactGeom.normal.X - contact.normal.X) < 1.026f)
                         && (Math.Abs(contactGeom.normal.Y - contact.normal.Y) < 0.303f)
-                        && (Math.Abs(contactGeom.normal.Z - contact.normal.Z) < 0.065f))
-                        && contactGeom.g1 != LandGeom && contactGeom.g2 != LandGeom)
+                        && (Math.Abs(contactGeom.normal.Z - contact.normal.Z) < 0.065f)))
                     {
                         if (Math.Abs(contact.depth - contactGeom.depth) < 0.052f)
                         {
@@ -1538,7 +1540,7 @@ namespace OpenSim.Region.Physics.OdePlugin
                     //d.GeomGetAABB(contactGeom.g2, out aabb2);
                     //d.GeomGetAABB(contactGeom.g1, out aabb1);
                     //aabb1.
-                    if (((Math.Abs(contactGeom.normal.X - contact.normal.X) < 1.026f) && (Math.Abs(contactGeom.normal.Y - contact.normal.Y) < 0.303f) && (Math.Abs(contactGeom.normal.Z - contact.normal.Z) < 0.065f)) && contactGeom.g1 != LandGeom && contactGeom.g2 != LandGeom)
+                    if (((Math.Abs(contactGeom.normal.X - contact.normal.X) < 1.026f) && (Math.Abs(contactGeom.normal.Y - contact.normal.Y) < 0.303f) && (Math.Abs(contactGeom.normal.Z - contact.normal.Z) < 0.065f)))
                     {
                         if (contactGeom.normal.X == contact.normal.X && contactGeom.normal.Y == contact.normal.Y && contactGeom.normal.Z == contact.normal.Z)
                         {
@@ -2896,6 +2898,8 @@ namespace OpenSim.Region.Physics.OdePlugin
         /// <returns>The number of frames simulated over that period.</returns>
         public override float Simulate(float timeStep)
         {
+            if (!_worldInitialized) return 11f;
+
             int startFrameTick = CollectStats ? Util.EnvironmentTickCount() : 0;
             int tempTick = 0, tempTick2 = 0;
 
@@ -4017,6 +4021,8 @@ namespace OpenSim.Region.Physics.OdePlugin
 
         public override void Dispose()
         {
+            _worldInitialized = false;
+
             m_rayCastManager.Dispose();
             m_rayCastManager = null;
 
@@ -4037,6 +4043,7 @@ namespace OpenSim.Region.Physics.OdePlugin
                 d.WorldDestroy(world);
                 //d.CloseODE();
             }
+
         }
 
         public override Dictionary<uint, float> GetTopColliders()