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

12 files changed, 713 insertions, 321 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index 3c48dcc..e2aa41e 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -82,7 +82,13 @@ public sealed class BSCharacter : BSPhysObject
     {
         _physicsActorType = (int)ActorTypes.Agent;
         _position = pos;
+
+        // Old versions of ScenePresence passed only the height. If width and/or depth are zero,
+        //     replace with the default values.
         _size = size;
+        if (_size.X == 0f) _size.X = PhysicsScene.Params.avatarCapsuleDepth;
+        if (_size.Y == 0f) _size.Y = PhysicsScene.Params.avatarCapsuleWidth;
+
         _flying = isFlying;
         _orientation = OMV.Quaternion.Identity;
         _velocity = OMV.Vector3.Zero;
@@ -175,8 +181,7 @@ public sealed class BSCharacter : BSPhysObject
         get
         {
             // Avatar capsule size is kept in the scale parameter.
-            // return _size;
-            return new OMV.Vector3(Scale.X * 2f, Scale.Y * 2f, Scale.Z);
+            return _size;
         }
 
         set {
@@ -184,8 +189,8 @@ public sealed class BSCharacter : BSPhysObject
             _size = value;
             ComputeAvatarScale(_size);
             ComputeAvatarVolumeAndMass();
-            DetailLog("{0},BSCharacter.setSize,call,scale={1},density={2},volume={3},mass={4}",
-                            LocalID, Scale, _avatarDensity, _avatarVolume, RawMass);
+            DetailLog("{0},BSCharacter.setSize,call,size={1},scale={2},density={3},volume={4},mass={5}",
+                            LocalID, _size, Scale, _avatarDensity, _avatarVolume, RawMass);
 
             PhysicsScene.TaintedObject("BSCharacter.setSize", delegate()
             {
@@ -203,9 +208,9 @@ public sealed class BSCharacter : BSPhysObject
         set { BaseShape = value; }
     }
     // I want the physics engine to make an avatar capsule
-    public override ShapeData.PhysicsShapeType PreferredPhysicalShape
+    public override PhysicsShapeType PreferredPhysicalShape
     {
-        get {return ShapeData.PhysicsShapeType.SHAPE_AVATAR; }
+        get {return PhysicsShapeType.SHAPE_CAPSULE; }
     }
 
     public override bool Grabbed {
@@ -614,13 +619,19 @@ public sealed class BSCharacter : BSPhysObject
         // The 'size' given by the simulator is the mid-point of the avatar
         //    and X and Y are unspecified.
 
-        OMV.Vector3 newScale = OMV.Vector3.Zero;
-        newScale.X = PhysicsScene.Params.avatarCapsuleRadius;
-        newScale.Y = PhysicsScene.Params.avatarCapsuleRadius;
+        OMV.Vector3 newScale = size;
+        // newScale.X = PhysicsScene.Params.avatarCapsuleWidth;
+        // newScale.Y = PhysicsScene.Params.avatarCapsuleDepth;
 
         // From the total height, remove the capsule half spheres that are at each end
-        newScale.Z = size.Z - (newScale.X + newScale.Y);
-        Scale = newScale;
+        // The 1.15f came from ODE. Not sure what this factors in.
+        // newScale.Z = (size.Z * 1.15f) - (newScale.X + newScale.Y);
+
+        // The total scale height is the central cylindar plus the caps on the two ends.
+        newScale.Z = size.Z + (Math.Min(size.X, size.Y) * 2f);
+
+        // Convert diameters to radii and height to half height -- the way Bullet expects it.
+        Scale = newScale / 2f;
     }
 
     // set _avatarVolume and _mass based on capsule size, _density and Scale
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
index 436e043..4ee047b 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
@@ -82,9 +82,9 @@ public abstract class BSLinkset
 
     // Some linksets have a preferred physical shape.
     // Returns SHAPE_UNKNOWN if there is no preference. Causes the correct shape to be selected.
-    public virtual ShapeData.PhysicsShapeType PreferredPhysicalShape(BSPhysObject requestor)
+    public virtual PhysicsShapeType PreferredPhysicalShape(BSPhysObject requestor)
     {
-        return ShapeData.PhysicsShapeType.SHAPE_UNKNOWN;
+        return PhysicsShapeType.SHAPE_UNKNOWN;
     }
 
     // Linksets move around the children so the linkset might need to compute the child position
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSLinksetCompound.cs b/OpenSim/Region/Physics/BulletSPlugin/BSLinksetCompound.cs
index 3238c85..cb37840 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSLinksetCompound.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSLinksetCompound.cs
@@ -42,12 +42,12 @@ public sealed class BSLinksetCompound : BSLinkset
     }
 
     // For compound implimented linksets, if there are children, use compound shape for the root.
-    public override ShapeData.PhysicsShapeType PreferredPhysicalShape(BSPhysObject requestor)
+    public override PhysicsShapeType PreferredPhysicalShape(BSPhysObject requestor)
     { 
-        ShapeData.PhysicsShapeType ret = ShapeData.PhysicsShapeType.SHAPE_UNKNOWN;
+        PhysicsShapeType ret = PhysicsShapeType.SHAPE_UNKNOWN;
         if (IsRoot(requestor) && HasAnyChildren)
         {
-            ret = ShapeData.PhysicsShapeType.SHAPE_COMPOUND;
+            ret = PhysicsShapeType.SHAPE_COMPOUND;
         }
         // DetailLog("{0},BSLinksetCompound.PreferredPhysicalShape,call,shape={1}", LinksetRoot.LocalID, ret);
         return ret;
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
index 991e5b1..e68b167 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
@@ -94,9 +94,9 @@ public abstract class BSPhysObject : PhysicsActor
     public PrimitiveBaseShape BaseShape { get; protected set; }
     // Some types of objects have preferred physical representations.
     // Returns SHAPE_UNKNOWN if there is no preference.
-    public virtual ShapeData.PhysicsShapeType PreferredPhysicalShape
+    public virtual PhysicsShapeType PreferredPhysicalShape
     {
-        get { return ShapeData.PhysicsShapeType.SHAPE_UNKNOWN; }
+        get { return PhysicsShapeType.SHAPE_UNKNOWN; }
     }
 
     // When the physical properties are updated, an EntityProperty holds the update values.
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 500c84a..5d16bbf 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -47,7 +47,6 @@ public sealed class BSPrim : BSPhysObject
     // _size is what the user passed. Scale is what we pass to the physics engine with the mesh.
     // Often Scale is unity because the meshmerizer will apply _size when creating the mesh.
     private OMV.Vector3 _size;  // the multiplier for each mesh dimension as passed by the user
-    // private OMV.Vector3 _scale; // the multiplier for each mesh dimension for the mesh as created by the meshmerizer
 
     private bool _grabbed;
     private bool _isSelected;
@@ -94,7 +93,7 @@ public sealed class BSPrim : BSPhysObject
         _physicsActorType = (int)ActorTypes.Prim;
         _position = pos;
         _size = size;
-        Scale = new OMV.Vector3(1f, 1f, 1f);   // the scale will be set by CreateGeom depending on object type
+        Scale = size;   // the scale will be set by CreateGeom depending on object type
         _orientation = rotation;
         _buoyancy = 1f;
         _velocity = OMV.Vector3.Zero;
@@ -155,6 +154,8 @@ public sealed class BSPrim : BSPhysObject
     public override OMV.Vector3 Size {
         get { return _size; }
         set {
+            // We presume the scale and size are the same. If scale must be changed for
+            //     the physical shape, that is done when the geometry is built.
             _size = value;
             ForceBodyShapeRebuild(false);
         }
@@ -170,7 +171,7 @@ public sealed class BSPrim : BSPhysObject
         }
     }
     // Whatever the linkset wants is what I want.
-    public override ShapeData.PhysicsShapeType PreferredPhysicalShape
+    public override PhysicsShapeType PreferredPhysicalShape
         { get { return Linkset.PreferredPhysicalShape(this); } }
 
     public override bool ForceBodyShapeRebuild(bool inTaintTime)
@@ -274,19 +275,19 @@ public sealed class BSPrim : BSPhysObject
             if (!Linkset.IsRoot(this))
                 _position = Linkset.Position(this);
 
-            // don't do the GetObjectPosition for root elements because this function is called a zillion times
+            // don't do the GetObjectPosition for root elements because this function is called a zillion times.
             // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
             return _position;
         }
         set {
-            // If you must push the position into the physics engine, use ForcePosition.
+            // If the position must be forced into the physics engine, use ForcePosition.
             if (_position == value)
             {
                 return;
             }
             _position = value;
             // TODO: what does it mean to set the position of a child prim?? Rebuild the constraint?
-            PositionSanityCheck();
+            PositionSanityCheck(false);
             PhysicsScene.TaintedObject("BSPrim.setPosition", delegate()
             {
                 // DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
@@ -302,7 +303,7 @@ public sealed class BSPrim : BSPhysObject
         }
         set {
             _position = value;
-            PositionSanityCheck();
+            // PositionSanityCheck();   // Don't do this! Causes a loop and caller should know better.
             BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
             ActivateIfPhysical(false);
         }
@@ -311,52 +312,43 @@ public sealed class BSPrim : BSPhysObject
     // Check that the current position is sane and, if not, modify the position to make it so.
     // Check for being below terrain and being out of bounds.
     // Returns 'true' of the position was made sane by some action.
-    private bool PositionSanityCheck()
+    private bool PositionSanityCheck(bool inTaintTime)
     {
         bool ret = false;
 
-        // If totally below the ground, move the prim up
-        // TODO: figure out the right solution for this... only for dynamic objects?
-        /*
         float terrainHeight = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(_position);
+        OMV.Vector3 upForce = OMV.Vector3.Zero;
         if (Position.Z < terrainHeight)
         {
             DetailLog("{0},BSPrim.PositionAdjustUnderGround,call,pos={1},terrain={2}", LocalID, _position, terrainHeight);
-            _position.Z = terrainHeight + 2.0f;
+            float targetHeight = terrainHeight + (Size.Z / 2f);
+            // Upforce proportional to the distance away from the terrain. Correct the error in 1 sec.
+            upForce.Z = (terrainHeight - Position.Z) * 1f;
             ret = true;
         }
-         */
+
         if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
         {
             float waterHeight = PhysicsScene.GetWaterLevelAtXYZ(_position);
             // TODO: a floating motor so object will bob in the water
-            if (Position.Z < waterHeight)
+            if (Math.Abs(Position.Z - waterHeight) > 0.1f)
             {
-                _position.Z = waterHeight;
+                // Upforce proportional to the distance away from the water. Correct the error in 1 sec.
+                upForce.Z = (waterHeight - Position.Z) * 1f;
                 ret = true;
             }
         }
 
         // TODO: check for out of bounds
-        return ret;
-    }
 
-    // A version of the sanity check that also makes sure a new position value is
-    //    pushed to the physics engine. This routine would be used by anyone
-    //    who is not already pushing the value.
-    private bool PositionSanityCheck(bool inTaintTime)
-    {
-        bool ret = false;
-        if (PositionSanityCheck())
+        // The above code computes a force to apply to correct any out-of-bounds problems. Apply same.
+        if (ret)
         {
-            // The new position value must be pushed into the physics engine but we can't
-            //    just assign to "Position" because of potential call loops.
-            PhysicsScene.TaintedObject(inTaintTime, "BSPrim.PositionSanityCheck", delegate()
+            PhysicsScene.TaintedObject(inTaintTime, "BSPrim.PositionSanityCheck:belowTerrain", delegate()
             {
-                DetailLog("{0},BSPrim.PositionSanityCheck,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                ForcePosition = _position;
+                // Apply upforce and overcome gravity.
+                ForceVelocity = ForceVelocity + upForce - PhysicsScene.DefaultGravity;
             });
-            ret = true;
         }
         return ret;
     }
@@ -940,6 +932,7 @@ public sealed class BSPrim : BSPhysObject
     public override void AddForce(OMV.Vector3 force, bool pushforce) {
         AddForce(force, pushforce, false);
     }
+    // Applying a force just adds this to the total force on the object.
     public void AddForce(OMV.Vector3 force, bool pushforce, bool inTaintTime) {
         // for an object, doesn't matter if force is a pushforce or not
         if (force.IsFinite())
@@ -971,6 +964,7 @@ public sealed class BSPrim : BSPhysObject
         });
     }
 
+    // An impulse force is scaled by the mass of the object.
     public void ApplyForceImpulse(OMV.Vector3 impulse, bool inTaintTime)
     {
         OMV.Vector3 applyImpulse = impulse;
@@ -1423,7 +1417,7 @@ public sealed class BSPrim : BSPhysObject
         if (changed != 0)
         {
             // Only update the position of single objects and linkset roots
-            if (this._parentPrim == null)
+            if (Linkset.IsRoot(this))
             {
                 base.RequestPhysicsterseUpdate();
             }
@@ -1435,19 +1429,24 @@ public sealed class BSPrim : BSPhysObject
         // Updates only for individual prims and for the root object of a linkset.
         if (Linkset.IsRoot(this))
         {
-            // Assign to the local variables so the normal set action does not happen
+            // Assign directly to the local variables so the normal set action does not happen
             _position = entprop.Position;
             _orientation = entprop.Rotation;
             _velocity = entprop.Velocity;
             _acceleration = entprop.Acceleration;
             _rotationalVelocity = entprop.RotationalVelocity;
 
+            // The sanity check can change the velocity and/or position.
+            if (PositionSanityCheck(true))
+            {
+                entprop.Position = _position;
+                entprop.Velocity = _velocity;
+            }
+
             // remember the current and last set values
             LastEntityProperties = CurrentEntityProperties;
             CurrentEntityProperties = entprop;
 
-            PositionSanityCheck(true);
-
             OMV.Vector3 direction = OMV.Vector3.UnitX * _orientation;
             DetailLog("{0},BSPrim.UpdateProperties,call,pos={1},orient={2},dir={3},vel={4},rotVel={5}",
                     LocalID, _position, _orientation, direction, _velocity, _rotationalVelocity);
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
index 2fee95e..27a78d1 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
@@ -712,7 +712,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
     // here just before the physics engine is called to step the simulation.
     public void ProcessTaints()
     {
-        InTaintTime = true;
+        InTaintTime = true; // Only used for debugging so locking is not necessary.
         ProcessRegularTaints();
         ProcessPostTaintTaints();
         InTaintTime = false;
@@ -758,6 +758,7 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
                 DetailLog("{0},BSScene.ProcessTaints,leftTaintsOnList,numNotProcessed={1}", DetailLogZero, _taintOperations.Count);
             }
              */
+
             // swizzle a new list into the list location so we can process what's there
             List<TaintCallbackEntry> oldList;
             lock (_taintLock)
@@ -787,8 +788,6 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
     //     will replace any previous operation by the same object.
     public void PostTaintObject(String ident, uint ID, TaintCallback callback)
     {
-        if (!m_initialized) return;
-
         string uniqueIdent = ident + "-" + ID.ToString();
         lock (_taintLock)
         {
@@ -864,13 +863,14 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
         }
     }
 
+    // Only used for debugging. Does not change state of anything so locking is not necessary.
     public bool AssertInTaintTime(string whereFrom)
     {
         if (!InTaintTime)
         {
             DetailLog("{0},BSScene.AssertInTaintTime,NOT IN TAINT TIME,Region={1},Where={2}", DetailLogZero, RegionName, whereFrom);
             m_log.ErrorFormat("{0} NOT IN TAINT TIME!! Region={1}, Where={2}", LogHeader, RegionName, whereFrom);
-            Util.PrintCallStack();
+            Util.PrintCallStack();  // Prints the stack into the DEBUG log file.
         }
         return InTaintTime;
     }
@@ -1145,6 +1145,11 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (s,p,l,v) => { s.UpdateParameterObject(ref s.m_params[0].contactProcessingThreshold, p, l, v); },
             (s,o,v) => { BulletSimAPI.SetContactProcessingThreshold2(o.PhysBody.ptr, v); } ),
 
+            new ParameterDefn("TerrainImplementation", "Type of shape to use for terrain (0=heightmap, 1=mesh)",
+            (float)BSTerrainPhys.TerrainImplementation.Mesh,
+            (s,cf,p,v) => { s.m_params[0].terrainImplementation = cf.GetFloat(p,v); },
+            (s) => { return s.m_params[0].terrainImplementation; },
+            (s,p,l,v) => { s.m_params[0].terrainImplementation = v; } ),
         new ParameterDefn("TerrainFriction", "Factor to reduce movement against terrain surface" ,
             0.5f,
             (s,cf,p,v) => { s.m_params[0].terrainFriction = cf.GetFloat(p, v); },
@@ -1180,11 +1185,16 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             (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.UpdateParameterObject(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.UpdateParameterObject(ref s.m_params[0].avatarCapsuleRadius, p, l, v); } ),
+        new ParameterDefn("AvatarCapsuleWidth", "The distance between the sides of the avatar capsule",
+            0.6f,
+            (s,cf,p,v) => { s.m_params[0].avatarCapsuleWidth = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarCapsuleWidth; },
+            (s,p,l,v) => { s.UpdateParameterObject(ref s.m_params[0].avatarCapsuleWidth, p, l, v); } ),
+        new ParameterDefn("AvatarCapsuleDepth", "The distance between the front and back of the avatar capsule",
+            0.45f,
+            (s,cf,p,v) => { s.m_params[0].avatarCapsuleDepth = cf.GetFloat(p, v); },
+            (s) => { return s.m_params[0].avatarCapsuleDepth; },
+            (s,p,l,v) => { s.UpdateParameterObject(ref s.m_params[0].avatarCapsuleDepth, 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); },
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
index 29a23c0..869735c 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
@@ -178,7 +178,7 @@ public sealed class BSShapeCollection : IDisposable
         bool ret = false;
         switch (shape.type)
         {
-            case ShapeData.PhysicsShapeType.SHAPE_MESH:
+            case PhysicsShapeType.SHAPE_MESH:
                 MeshDesc meshDesc;
                 if (Meshes.TryGetValue(shape.shapeKey, out meshDesc))
                 {
@@ -201,7 +201,7 @@ public sealed class BSShapeCollection : IDisposable
                 meshDesc.lastReferenced = System.DateTime.Now;
                 Meshes[shape.shapeKey] = meshDesc;
                 break;
-            case ShapeData.PhysicsShapeType.SHAPE_HULL:
+            case PhysicsShapeType.SHAPE_HULL:
                 HullDesc hullDesc;
                 if (Hulls.TryGetValue(shape.shapeKey, out hullDesc))
                 {
@@ -224,7 +224,7 @@ public sealed class BSShapeCollection : IDisposable
                 hullDesc.lastReferenced = System.DateTime.Now;
                 Hulls[shape.shapeKey] = hullDesc;
                 break;
-            case ShapeData.PhysicsShapeType.SHAPE_UNKNOWN:
+            case PhysicsShapeType.SHAPE_UNKNOWN:
                 break;
             default:
                 // Native shapes are not tracked and they don't go into any list
@@ -255,16 +255,16 @@ public sealed class BSShapeCollection : IDisposable
                 {
                     switch (shape.type)
                     {
-                        case ShapeData.PhysicsShapeType.SHAPE_HULL:
+                        case PhysicsShapeType.SHAPE_HULL:
                             DereferenceHull(shape, shapeCallback);
                             break;
-                        case ShapeData.PhysicsShapeType.SHAPE_MESH:
+                        case PhysicsShapeType.SHAPE_MESH:
                             DereferenceMesh(shape, shapeCallback);
                             break;
-                        case ShapeData.PhysicsShapeType.SHAPE_COMPOUND:
+                        case PhysicsShapeType.SHAPE_COMPOUND:
                             DereferenceCompound(shape, shapeCallback);
                             break;
-                        case ShapeData.PhysicsShapeType.SHAPE_UNKNOWN:
+                        case PhysicsShapeType.SHAPE_UNKNOWN:
                             break;
                         default:
                             break;
@@ -352,28 +352,28 @@ public sealed class BSShapeCollection : IDisposable
         BulletShape shapeInfo = new BulletShape(cShape);
         if (TryGetMeshByPtr(cShape, out meshDesc))
         {
-            shapeInfo.type = ShapeData.PhysicsShapeType.SHAPE_MESH;
+            shapeInfo.type = PhysicsShapeType.SHAPE_MESH;
             shapeInfo.shapeKey = meshDesc.shapeKey;
         }
         else
         {
             if (TryGetHullByPtr(cShape, out hullDesc))
             {
-                shapeInfo.type = ShapeData.PhysicsShapeType.SHAPE_HULL;
+                shapeInfo.type = PhysicsShapeType.SHAPE_HULL;
                 shapeInfo.shapeKey = hullDesc.shapeKey;
             }
             else
             {
                 if (BulletSimAPI.IsCompound2(cShape))
                 {
-                    shapeInfo.type = ShapeData.PhysicsShapeType.SHAPE_COMPOUND;
+                    shapeInfo.type = PhysicsShapeType.SHAPE_COMPOUND;
                 }
                 else
                 {
                     if (BulletSimAPI.IsNativeShape2(cShape))
                     {
                         shapeInfo.isNativeShape = true;
-                        shapeInfo.type = ShapeData.PhysicsShapeType.SHAPE_BOX; // (technically, type doesn't matter)
+                        shapeInfo.type = PhysicsShapeType.SHAPE_BOX; // (technically, type doesn't matter)
                     }
                 }
             }
@@ -381,7 +381,7 @@ public sealed class BSShapeCollection : IDisposable
 
         DetailLog("{0},BSShapeCollection.DereferenceAnonCollisionShape,shape={1}", BSScene.DetailLogZero, shapeInfo);
 
-        if (shapeInfo.type != ShapeData.PhysicsShapeType.SHAPE_UNKNOWN)
+        if (shapeInfo.type != PhysicsShapeType.SHAPE_UNKNOWN)
         {
             DereferenceShape(shapeInfo, true, null);
         }
@@ -405,11 +405,11 @@ public sealed class BSShapeCollection : IDisposable
         bool ret = false;
         bool haveShape = false;
 
-        if (!haveShape && prim.PreferredPhysicalShape == ShapeData.PhysicsShapeType.SHAPE_AVATAR)
+        if (!haveShape && prim.PreferredPhysicalShape == PhysicsShapeType.SHAPE_CAPSULE)
         {
             // an avatar capsule is close to a native shape (it is not shared)
-            ret = GetReferenceToNativeShape(prim, ShapeData.PhysicsShapeType.SHAPE_AVATAR,
-                            ShapeData.FixedShapeKey.KEY_CAPSULE, shapeCallback);
+            ret = GetReferenceToNativeShape(prim, PhysicsShapeType.SHAPE_CAPSULE,
+                            FixedShapeKey.KEY_CAPSULE, shapeCallback);
             DetailLog("{0},BSShapeCollection.CreateGeom,avatarCapsule,shape={1}", prim.LocalID, prim.PhysShape);
             ret = true;
             haveShape = true;
@@ -417,7 +417,7 @@ public sealed class BSShapeCollection : IDisposable
 
         // Compound shapes are handled special as they are rebuilt from scratch.
         // This isn't too great a hardship since most of the child shapes will already been created.
-        if (!haveShape && prim.PreferredPhysicalShape == ShapeData.PhysicsShapeType.SHAPE_COMPOUND)
+        if (!haveShape && prim.PreferredPhysicalShape == PhysicsShapeType.SHAPE_COMPOUND)
         {
             ret = GetReferenceToCompoundShape(prim, shapeCallback);
             DetailLog("{0},BSShapeCollection.CreateGeom,compoundShape,shape={1}", prim.LocalID, prim.PhysShape);
@@ -460,11 +460,11 @@ public sealed class BSShapeCollection : IDisposable
                 haveShape = true;
                 if (forceRebuild
                         || prim.Scale != prim.Size
-                        || prim.PhysShape.type != ShapeData.PhysicsShapeType.SHAPE_SPHERE
+                        || prim.PhysShape.type != PhysicsShapeType.SHAPE_SPHERE
                         )
                 {
-                    ret = GetReferenceToNativeShape(prim, ShapeData.PhysicsShapeType.SHAPE_SPHERE,
-                                            ShapeData.FixedShapeKey.KEY_SPHERE, shapeCallback);
+                    ret = GetReferenceToNativeShape(prim, PhysicsShapeType.SHAPE_SPHERE,
+                                            FixedShapeKey.KEY_SPHERE, shapeCallback);
                     DetailLog("{0},BSShapeCollection.CreateGeom,sphere,force={1},shape={2}",
                                         prim.LocalID, forceRebuild, prim.PhysShape);
                 }
@@ -474,11 +474,11 @@ public sealed class BSShapeCollection : IDisposable
                 haveShape = true;
                 if (forceRebuild
                         || prim.Scale != prim.Size
-                        || prim.PhysShape.type != ShapeData.PhysicsShapeType.SHAPE_BOX
+                        || prim.PhysShape.type != PhysicsShapeType.SHAPE_BOX
                         )
                 {
-                    ret = GetReferenceToNativeShape( prim, ShapeData.PhysicsShapeType.SHAPE_BOX,
-                                            ShapeData.FixedShapeKey.KEY_BOX, shapeCallback);
+                    ret = GetReferenceToNativeShape( prim, PhysicsShapeType.SHAPE_BOX,
+                                            FixedShapeKey.KEY_BOX, shapeCallback);
                     DetailLog("{0},BSShapeCollection.CreateGeom,box,force={1},shape={2}",
                                         prim.LocalID, forceRebuild, prim.PhysShape);
                 }
@@ -519,15 +519,12 @@ public sealed class BSShapeCollection : IDisposable
     // Creates a native shape and assignes it to prim.BSShape.
     // "Native" shapes are never shared. they are created here and destroyed in DereferenceShape().
     private bool GetReferenceToNativeShape(BSPhysObject prim,
-                            ShapeData.PhysicsShapeType shapeType, ShapeData.FixedShapeKey shapeKey,
+                            PhysicsShapeType shapeType, FixedShapeKey shapeKey,
                             ShapeDestructionCallback shapeCallback)
     {
         // release any previous shape
         DereferenceShape(prim.PhysShape, true, shapeCallback);
 
-        // Bullet native objects are scaled by the Bullet engine so pass the size in
-        prim.Scale = prim.Size;
-
         BulletShape newShape = BuildPhysicalNativeShape(prim, shapeType, shapeKey);
 
         // Don't need to do a 'ReferenceShape()' here because native shapes are not shared.
@@ -538,8 +535,8 @@ public sealed class BSShapeCollection : IDisposable
         return true;
     }
 
-    private BulletShape BuildPhysicalNativeShape(BSPhysObject prim, ShapeData.PhysicsShapeType shapeType,
-                                    ShapeData.FixedShapeKey shapeKey)
+    private BulletShape BuildPhysicalNativeShape(BSPhysObject prim, PhysicsShapeType shapeType,
+                                    FixedShapeKey shapeKey)
     {
         BulletShape newShape;
         // Need to make sure the passed shape information is for the native type.
@@ -547,12 +544,13 @@ public sealed class BSShapeCollection : IDisposable
         nativeShapeData.Type = shapeType;
         nativeShapeData.ID = prim.LocalID;
         nativeShapeData.Scale = prim.Scale;
-        nativeShapeData.Size = prim.Scale;
+        nativeShapeData.Size = prim.Scale;  // unneeded, I think.
         nativeShapeData.MeshKey = (ulong)shapeKey;
         nativeShapeData.HullKey = (ulong)shapeKey;
 
-        if (shapeType == ShapeData.PhysicsShapeType.SHAPE_AVATAR)
+        if (shapeType == PhysicsShapeType.SHAPE_CAPSULE)
         {
+            // The proper scale has been calculated in the prim.
             newShape = new BulletShape(
                         BulletSimAPI.BuildCapsuleShape2(PhysicsScene.World.ptr, 1f, 1f, prim.Scale)
                         , shapeType);
@@ -560,6 +558,9 @@ public sealed class BSShapeCollection : IDisposable
         }
         else
         {
+            // Native shapes are scaled in Bullet so set the scaling to the size
+            prim.Scale = prim.Size;
+            nativeShapeData.Scale = prim.Scale;
             newShape = new BulletShape(BulletSimAPI.BuildNativeShape2(PhysicsScene.World.ptr, nativeShapeData), shapeType);
         }
         if (newShape.ptr == IntPtr.Zero)
@@ -585,7 +586,7 @@ public sealed class BSShapeCollection : IDisposable
         System.UInt64 newMeshKey = ComputeShapeKey(prim.Size, prim.BaseShape, out lod);
 
         // if this new shape is the same as last time, don't recreate the mesh
-        if (newMeshKey == prim.PhysShape.shapeKey && prim.PhysShape.type == ShapeData.PhysicsShapeType.SHAPE_MESH)
+        if (newMeshKey == prim.PhysShape.shapeKey && prim.PhysShape.type == PhysicsShapeType.SHAPE_MESH)
             return false;
 
         DetailLog("{0},BSShapeCollection.GetReferenceToMesh,create,oldKey={1},newKey={2}",
@@ -643,7 +644,7 @@ public sealed class BSShapeCollection : IDisposable
                                     indices.GetLength(0), indices, vertices.Count, verticesAsFloats);
             }
         }
-        BulletShape newShape = new BulletShape(meshPtr, ShapeData.PhysicsShapeType.SHAPE_MESH);
+        BulletShape newShape = new BulletShape(meshPtr, PhysicsShapeType.SHAPE_MESH);
         newShape.shapeKey = newMeshKey;
 
         return newShape;
@@ -659,7 +660,7 @@ public sealed class BSShapeCollection : IDisposable
         System.UInt64 newHullKey = ComputeShapeKey(prim.Size, prim.BaseShape, out lod);
 
         // if the hull hasn't changed, don't rebuild it
-        if (newHullKey == prim.PhysShape.shapeKey && prim.PhysShape.type == ShapeData.PhysicsShapeType.SHAPE_HULL)
+        if (newHullKey == prim.PhysShape.shapeKey && prim.PhysShape.type == PhysicsShapeType.SHAPE_HULL)
             return false;
 
         DetailLog("{0},BSShapeCollection.GetReferenceToHull,create,oldKey={1},newKey={2}",
@@ -780,7 +781,7 @@ public sealed class BSShapeCollection : IDisposable
             }
         }
 
-        BulletShape newShape = new BulletShape(hullPtr, ShapeData.PhysicsShapeType.SHAPE_HULL);
+        BulletShape newShape = new BulletShape(hullPtr, PhysicsShapeType.SHAPE_HULL);
         newShape.shapeKey = newHullKey;
 
         return newShape;        // 'true' means a new shape has been added to this prim
@@ -803,7 +804,7 @@ public sealed class BSShapeCollection : IDisposable
         // DereferenceShape(prim.PhysShape, true, shapeCallback);
 
         BulletShape cShape = new BulletShape(
-            BulletSimAPI.CreateCompoundShape2(PhysicsScene.World.ptr, false), ShapeData.PhysicsShapeType.SHAPE_COMPOUND);
+            BulletSimAPI.CreateCompoundShape2(PhysicsScene.World.ptr, false), PhysicsShapeType.SHAPE_COMPOUND);
 
         // Create the shape for the root prim and add it to the compound shape. Cannot be a native shape.
         CreateGeomMeshOrHull(prim, shapeCallback);
@@ -894,7 +895,7 @@ public sealed class BSShapeCollection : IDisposable
 
         // While we figure out the real problem, stick a simple native shape on the object.
         BulletShape fillinShape =
-            BuildPhysicalNativeShape(prim, ShapeData.PhysicsShapeType.SHAPE_BOX, ShapeData.FixedShapeKey.KEY_BOX);
+            BuildPhysicalNativeShape(prim, PhysicsShapeType.SHAPE_BOX, FixedShapeKey.KEY_BOX);
 
         return fillinShape;
     }
@@ -940,7 +941,7 @@ public sealed class BSShapeCollection : IDisposable
             else
             {
                 bodyPtr = BulletSimAPI.CreateGhostFromShape2(sim.ptr, shape.ptr,
-                                        prim.LocalID, prim.ForcePosition, prim.ForceOrientation);
+                                        prim.LocalID, prim.RawPosition, prim.RawOrientation);
                 DetailLog("{0},BSShapeCollection.CreateBody,ghost,ptr={1}", prim.LocalID, bodyPtr.ToString("X"));
             }
             aBody = new BulletBody(prim.LocalID, bodyPtr);
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSShapes.cs b/OpenSim/Region/Physics/BulletSPlugin/BSShapes.cs
index d59a486..f2e62d9 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSShapes.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSShapes.cs
@@ -35,7 +35,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
 public abstract class BSShape
 {
     public IntPtr ptr { get; set; }
-    public ShapeData.PhysicsShapeType type { get; set; }
+    public PhysicsShapeType type { get; set; }
     public System.UInt64 key { get; set; }
     public int referenceCount { get; set; }
     public DateTime lastReferenced { get; set; }
@@ -43,7 +43,7 @@ public abstract class BSShape
     public BSShape()
     {
         ptr = IntPtr.Zero;
-        type = ShapeData.PhysicsShapeType.SHAPE_UNKNOWN;
+        type = PhysicsShapeType.SHAPE_UNKNOWN;
         key = 0;
         referenceCount = 0;
         lastReferenced = DateTime.Now;
@@ -54,17 +54,17 @@ public abstract class BSShape
     {
         BSShape ret = null;
 
-        if (prim.PreferredPhysicalShape == ShapeData.PhysicsShapeType.SHAPE_AVATAR)
+        if (prim.PreferredPhysicalShape == PhysicsShapeType.SHAPE_CAPSULE)
         {
             // an avatar capsule is close to a native shape (it is not shared)
-            ret = BSShapeNative.GetReference(physicsScene, prim, ShapeData.PhysicsShapeType.SHAPE_AVATAR,
-                                        ShapeData.FixedShapeKey.KEY_CAPSULE);
+            ret = BSShapeNative.GetReference(physicsScene, prim, PhysicsShapeType.SHAPE_CAPSULE,
+                                        FixedShapeKey.KEY_CAPSULE);
             physicsScene.DetailLog("{0},BSShape.GetShapeReference,avatarCapsule,shape={1}", prim.LocalID, ret);
         }
 
         // Compound shapes are handled special as they are rebuilt from scratch.
         // This isn't too great a hardship since most of the child shapes will already been created.
-        if (ret == null  && prim.PreferredPhysicalShape == ShapeData.PhysicsShapeType.SHAPE_COMPOUND)
+        if (ret == null  && prim.PreferredPhysicalShape == PhysicsShapeType.SHAPE_COMPOUND)
         {
             // Getting a reference to a compound shape gets you the compound shape with the root prim shape added
             ret = BSShapeCompound.GetReference(prim);
@@ -123,14 +123,14 @@ public class BSShapeNative : BSShape
     {
     }
     public static BSShape GetReference(BSScene physicsScene, BSPhysObject prim, 
-                    ShapeData.PhysicsShapeType shapeType, ShapeData.FixedShapeKey shapeKey) 
+                    PhysicsShapeType shapeType, FixedShapeKey shapeKey) 
     {
         // Native shapes are not shared and are always built anew.
         return new BSShapeNative(physicsScene, prim, shapeType, shapeKey);
     }
 
     private BSShapeNative(BSScene physicsScene, BSPhysObject prim,
-                    ShapeData.PhysicsShapeType shapeType, ShapeData.FixedShapeKey shapeKey)
+                    PhysicsShapeType shapeType, FixedShapeKey shapeKey)
     {
         ShapeData nativeShapeData = new ShapeData();
         nativeShapeData.Type = shapeType;
@@ -141,7 +141,7 @@ public class BSShapeNative : BSShape
         nativeShapeData.HullKey = (ulong)shapeKey;
 
        
-        if (shapeType == ShapeData.PhysicsShapeType.SHAPE_AVATAR)
+        if (shapeType == PhysicsShapeType.SHAPE_CAPSULE)
         {
             ptr = BulletSimAPI.BuildCapsuleShape2(physicsScene.World.ptr, 1f, 1f, prim.Scale);
             physicsScene.DetailLog("{0},BSShapeCollection.BuiletPhysicalNativeShape,capsule,scale={1}", prim.LocalID, prim.Scale);
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs
new file mode 100755
index 0000000..8fc36d1
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainHeightmap.cs
@@ -0,0 +1,170 @@
+/*
+ * 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 OpenSim.Framework;
+using OpenSim.Region.Framework;
+using OpenSim.Region.CoreModules;
+using OpenSim.Region.Physics.Manager;
+
+using Nini.Config;
+using log4net;
+
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+public sealed class BSTerrainHeightmap : BSTerrainPhys
+{
+    static string LogHeader = "[BULLETSIM TERRAIN HEIGHTMAP]";
+
+    BulletHeightMapInfo m_mapInfo = null;
+
+    // Constructor to build a default, flat heightmap terrain.
+    public BSTerrainHeightmap(BSScene physicsScene, Vector3 regionBase, uint id, Vector3 regionSize)
+        : base(physicsScene, regionBase, id)
+    {
+        Vector3 minTerrainCoords = new Vector3(0f, 0f, BSTerrainManager.HEIGHT_INITIALIZATION - BSTerrainManager.HEIGHT_EQUAL_FUDGE);
+        Vector3 maxTerrainCoords = new Vector3(regionSize.X, regionSize.Y, BSTerrainManager.HEIGHT_INITIALIZATION);
+        int totalHeights = (int)maxTerrainCoords.X * (int)maxTerrainCoords.Y;
+        float[] initialMap = new float[totalHeights];
+        for (int ii = 0; ii < totalHeights; ii++)
+        {
+            initialMap[ii] = BSTerrainManager.HEIGHT_INITIALIZATION;
+        }
+        m_mapInfo = new BulletHeightMapInfo(id, initialMap, IntPtr.Zero);
+        m_mapInfo.minCoords = minTerrainCoords;
+        m_mapInfo.maxCoords = maxTerrainCoords;
+        m_mapInfo.terrainRegionBase = TerrainBase;
+        // Don't have to free any previous since we just got here.
+        BuildHeightmapTerrain();
+    }
+
+    // This minCoords and maxCoords passed in give the size of the terrain (min and max Z
+    //         are the high and low points of the heightmap).
+    public BSTerrainHeightmap(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
+                                                    Vector3 minCoords, Vector3 maxCoords)
+        : base(physicsScene, regionBase, id)
+    {
+        m_mapInfo = new BulletHeightMapInfo(id, initialMap, IntPtr.Zero);
+        m_mapInfo.minCoords = minCoords;
+        m_mapInfo.maxCoords = maxCoords;
+        m_mapInfo.minZ = minCoords.Z;
+        m_mapInfo.maxZ = maxCoords.Z;
+        m_mapInfo.terrainRegionBase = TerrainBase;
+
+        // Don't have to free any previous since we just got here.
+        BuildHeightmapTerrain();
+    }
+
+    public override void Dispose()
+    {
+        ReleaseHeightMapTerrain();
+    }
+
+    // Using the information in m_mapInfo, create the physical representation of the heightmap.
+    private void BuildHeightmapTerrain()
+    {
+        m_mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, m_mapInfo.ID,
+                                m_mapInfo.minCoords, m_mapInfo.maxCoords, 
+                                m_mapInfo.heightMap, BSTerrainManager.TERRAIN_COLLISION_MARGIN);
+
+        // Create the terrain shape from the mapInfo
+        m_mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(m_mapInfo.Ptr),
+                                                    PhysicsShapeType.SHAPE_TERRAIN);
+
+        // The terrain object initial position is at the center of the object
+        Vector3 centerPos;
+        centerPos.X = m_mapInfo.minCoords.X + (m_mapInfo.sizeX / 2f);
+        centerPos.Y = m_mapInfo.minCoords.Y + (m_mapInfo.sizeY / 2f);
+        centerPos.Z = m_mapInfo.minZ + ((m_mapInfo.maxZ - m_mapInfo.minZ) / 2f);
+
+        m_mapInfo.terrainBody = new BulletBody(m_mapInfo.ID,
+                BulletSimAPI.CreateBodyWithDefaultMotionState2(m_mapInfo.terrainShape.ptr,
+                                            m_mapInfo.ID, centerPos, Quaternion.Identity));
+
+        // Set current terrain attributes
+        BulletSimAPI.SetFriction2(m_mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainFriction);
+        BulletSimAPI.SetHitFraction2(m_mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainHitFraction);
+        BulletSimAPI.SetRestitution2(m_mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainRestitution);
+        BulletSimAPI.SetCollisionFlags2(m_mapInfo.terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+        // Return the new terrain to the world of physical objects
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+
+        // redo its bounding box now that it is in the world
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+
+        BulletSimAPI.SetCollisionFilterMask2(m_mapInfo.terrainBody.ptr,
+                            (uint)CollisionFilterGroups.TerrainFilter,
+                            (uint)CollisionFilterGroups.TerrainMask);
+
+        // Make it so the terrain will not move or be considered for movement.
+        BulletSimAPI.ForceActivationState2(m_mapInfo.terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
+
+        return;
+    }
+
+    // If there is information in m_mapInfo pointing to physical structures, release same.
+    private void ReleaseHeightMapTerrain()
+    {
+        if (m_mapInfo != null)
+        {
+            if (m_mapInfo.terrainBody.ptr != IntPtr.Zero)
+            {
+                BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+                // Frees both the body and the shape.
+                BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_mapInfo.terrainBody.ptr);
+                BulletSimAPI.ReleaseHeightMapInfo2(m_mapInfo.Ptr);
+            }
+        }
+        m_mapInfo = null;
+    }
+
+    // The passed position is relative to the base of the region.
+    public override float GetHeightAtXYZ(Vector3 pos)
+    {
+        float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+
+        int mapIndex = (int)pos.Y * (int)m_mapInfo.sizeY + (int)pos.X;
+        try
+        {
+            ret = m_mapInfo.heightMap[mapIndex];
+        }
+        catch
+        {
+            // Sometimes they give us wonky values of X and Y. Give a warning and return something.
+            PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, pos={2}",
+                                LogHeader, m_mapInfo.terrainRegionBase, pos);
+            ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+        }
+        return ret;
+    }
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
index 7c34af2..71fca33 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
@@ -40,6 +40,32 @@ using OpenMetaverse;
 
 namespace OpenSim.Region.Physics.BulletSPlugin
 {
+
+// The physical implementation of the terrain is wrapped in this class.
+public abstract class BSTerrainPhys : IDisposable
+{
+    public enum TerrainImplementation
+    {
+        Heightmap   = 0,
+        Mesh        = 1
+    }
+
+    public BSScene PhysicsScene { get; private set; }
+    // Base of the region in world coordinates. Coordinates inside the region are relative to this.
+    public Vector3 TerrainBase { get; private set; }
+    public uint ID { get; private set; }
+
+    public BSTerrainPhys(BSScene physicsScene, Vector3 regionBase, uint id)
+    {
+        PhysicsScene = physicsScene;
+        TerrainBase = regionBase;
+        ID = id;
+    }
+    public abstract void Dispose();
+    public abstract float GetHeightAtXYZ(Vector3 pos);
+}
+
+// ==========================================================================================
 public sealed class BSTerrainManager
 {
     static string LogHeader = "[BULLETSIM TERRAIN MANAGER]";
@@ -67,11 +93,10 @@ public sealed class BSTerrainManager
 
     // If doing mega-regions, if we're region zero we will be managing multiple
     //    region terrains since region zero does the physics for the whole mega-region.
-    private Dictionary<Vector2, BulletHeightMapInfo> m_heightMaps;
+    private Dictionary<Vector3, BSTerrainPhys> m_terrains;
 
-    // True of the terrain has been modified.
-    // Used to force recalculation of terrain height after terrain has been modified
-    private bool m_terrainModified;
+    // Flags used to know when to recalculate the height.
+    private bool m_terrainModified = false;
 
     // If we are doing mega-regions, terrains are added from TERRAIN_ID to m_terrainCount.
     // This is incremented before assigning to new region so it is the last ID allocated.
@@ -89,8 +114,7 @@ public sealed class BSTerrainManager
     public BSTerrainManager(BSScene physicsScene)
     {
         PhysicsScene = physicsScene;
-        m_heightMaps = new Dictionary<Vector2,BulletHeightMapInfo>();
-        m_terrainModified = false;
+        m_terrains = new Dictionary<Vector3,BSTerrainPhys>();
 
         // Assume one region of default size
         m_worldOffset = Vector3.Zero;
@@ -99,9 +123,6 @@ public sealed class BSTerrainManager
     }
 
     // Create the initial instance of terrain and the underlying ground plane.
-    // The objects are allocated in the unmanaged space and the pointers are tracked
-    //    by the managed code.
-    // The terrains and the groundPlane are not added to the list of PhysObjects.
     // This is called from the initialization routine so we presume it is
     //    safe to call Bullet in real time. We hope no one is moving prims around yet.
     public void CreateInitialGroundPlaneAndTerrain()
@@ -109,7 +130,7 @@ public sealed class BSTerrainManager
         // The ground plane is here to catch things that are trying to drop to negative infinity
         BulletShape groundPlaneShape = new BulletShape(
                     BulletSimAPI.CreateGroundPlaneShape2(BSScene.GROUNDPLANE_ID, 1f, TERRAIN_COLLISION_MARGIN),
-                    ShapeData.PhysicsShapeType.SHAPE_GROUNDPLANE);
+                    PhysicsShapeType.SHAPE_GROUNDPLANE);
         m_groundPlane = new BulletBody(BSScene.GROUNDPLANE_ID,
                         BulletSimAPI.CreateBodyWithDefaultMotionState2(groundPlaneShape.ptr, BSScene.GROUNDPLANE_ID,
                                                             Vector3.Zero, Quaternion.Identity));
@@ -121,15 +142,9 @@ public sealed class BSTerrainManager
         BulletSimAPI.SetCollisionFilterMask2(m_groundPlane.ptr,
                         (uint)CollisionFilterGroups.GroundPlaneFilter, (uint)CollisionFilterGroups.GroundPlaneMask);
 
-        Vector3 minTerrainCoords = new Vector3(0f, 0f, HEIGHT_INITIALIZATION - HEIGHT_EQUAL_FUDGE);
-        Vector3 maxTerrainCoords = new Vector3(DefaultRegionSize.X, DefaultRegionSize.Y, HEIGHT_INITIALIZATION);
-        int totalHeights = (int)maxTerrainCoords.X * (int)maxTerrainCoords.Y;
-        float[] initialMap = new float[totalHeights];
-        for (int ii = 0; ii < totalHeights; ii++)
-        {
-            initialMap[ii] = HEIGHT_INITIALIZATION;
-        }
-        UpdateOrCreateTerrain(BSScene.TERRAIN_ID, initialMap, minTerrainCoords, maxTerrainCoords, true);
+        // Build an initial terrain and put it in the world. This quickly gets replaced by the real region terrain.
+        BSTerrainPhys initialTerrain = new BSTerrainHeightmap(PhysicsScene, Vector3.Zero, BSScene.TERRAIN_ID, DefaultRegionSize);
+        m_terrains.Add(Vector3.Zero, initialTerrain);
     }
 
     // Release all the terrain structures we might have allocated
@@ -150,15 +165,11 @@ public sealed class BSTerrainManager
     // Release all the terrain we have allocated
     public void ReleaseTerrain()
     {
-        foreach (KeyValuePair<Vector2, BulletHeightMapInfo> kvp in m_heightMaps)
+        foreach (KeyValuePair<Vector3, BSTerrainPhys> kvp in m_terrains)
         {
-            if (BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, kvp.Value.terrainBody.ptr))
-            {
-                BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, kvp.Value.terrainBody.ptr);
-                BulletSimAPI.ReleaseHeightMapInfo2(kvp.Value.Ptr);
-            }
+            kvp.Value.Dispose();
         }
-        m_heightMaps.Clear();
+        m_terrains.Clear();
     }
 
     // The simulator wants to set a new heightmap for the terrain.
@@ -176,8 +187,9 @@ public sealed class BSTerrainManager
                 {
                     DetailLog("{0},SetTerrain.ToParent,offset={1},worldMax={2}",
                                     BSScene.DetailLogZero, m_worldOffset, m_worldMax);
-                    ((BSScene)MegaRegionParentPhysicsScene).TerrainManager.UpdateOrCreateTerrain(BSScene.CHILDTERRAIN_ID,
-                                    localHeightMap, m_worldOffset, m_worldOffset + DefaultRegionSize, true);
+                    ((BSScene)MegaRegionParentPhysicsScene).TerrainManager.UpdateTerrain(
+                                    BSScene.CHILDTERRAIN_ID, localHeightMap, 
+                                    m_worldOffset, m_worldOffset + DefaultRegionSize, true);
                 }
             }
             else
@@ -185,7 +197,7 @@ public sealed class BSTerrainManager
                 // If not doing the mega-prim thing, just change the terrain
                 DetailLog("{0},SetTerrain.Existing", BSScene.DetailLogZero);
 
-                UpdateOrCreateTerrain(BSScene.TERRAIN_ID, localHeightMap,
+                UpdateTerrain(BSScene.TERRAIN_ID, localHeightMap,
                                     m_worldOffset, m_worldOffset + DefaultRegionSize, true);
             }
         });
@@ -195,56 +207,63 @@ public sealed class BSTerrainManager
     //     based on the passed information. The 'id' should be either the terrain id or
     //     BSScene.CHILDTERRAIN_ID. If the latter, a new child terrain ID will be allocated and used.
     //     The latter feature is for creating child terrains for mega-regions.
-    // If called with a mapInfo in m_heightMaps but the terrain has no body yet (mapInfo.terrainBody.Ptr == 0)
-    //     then a new body and shape is created and the mapInfo is filled.
-    //     This call is used for doing the initial terrain creation.
     // If called with a mapInfo in m_heightMaps and there is an existing terrain body, a new
     //     terrain shape is created and added to the body.
     //     This call is most often used to update the heightMap and parameters of the terrain.
     // (The above does suggest that some simplification/refactoring is in order.)
-    private void UpdateOrCreateTerrain(uint id, float[] heightMap, Vector3 minCoords, Vector3 maxCoords, bool inTaintTime)
+    private void UpdateTerrain(uint id, float[] heightMap, 
+                            Vector3 minCoords, Vector3 maxCoords, bool inTaintTime)
     {
-        DetailLog("{0},BSTerrainManager.UpdateOrCreateTerrain,call,minC={1},maxC={2},inTaintTime={3}",
+        DetailLog("{0},BSTerrainManager.UpdateTerrain,call,minC={1},maxC={2},inTaintTime={3}",
                             BSScene.DetailLogZero, minCoords, maxCoords, inTaintTime);
 
+        // Find high and low points of passed heightmap.
+        // The min and max passed in is usually the area objects can be in (maximum
+        //     object height, for instance). The terrain wants the bounding box for the
+        //     terrain so we replace passed min and max Z with the actual terrain min/max Z.
         float minZ = float.MaxValue;
         float maxZ = float.MinValue;
-        Vector2 terrainRegionBase = new Vector2(minCoords.X, minCoords.Y);
-
-        int heightMapSize = heightMap.Length;
-        for (int ii = 0; ii < heightMapSize; ii++)
+        foreach (float height in heightMap)
         {
-            float height = heightMap[ii];
             if (height < minZ) minZ = height;
             if (height > maxZ) maxZ = height;
         }
-
-        // The shape of the terrain is from its base to its extents.
+        if (minZ == maxZ)
+        {
+            // If min and max are the same, reduce min a little bit so a good bounding box is created.
+            minZ -= BSTerrainManager.HEIGHT_EQUAL_FUDGE;
+        }
         minCoords.Z = minZ;
         maxCoords.Z = maxZ;
 
-        BulletHeightMapInfo mapInfo;
-        if (m_heightMaps.TryGetValue(terrainRegionBase, out mapInfo))
+        Vector3 terrainRegionBase = new Vector3(minCoords.X, minCoords.Y, 0f);
+
+        BSTerrainPhys terrainPhys;
+        if (m_terrains.TryGetValue(terrainRegionBase, out terrainPhys))
         {
-            // If this is terrain we know about, it's easy to update
-
-            mapInfo.heightMap = heightMap;
-            mapInfo.minCoords = minCoords;
-            mapInfo.maxCoords = maxCoords;
-            mapInfo.minZ = minZ;
-            mapInfo.maxZ = maxZ;
-            mapInfo.sizeX = maxCoords.X - minCoords.X;
-            mapInfo.sizeY = maxCoords.Y - minCoords.Y;
-            DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,call,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}",
-                        BSScene.DetailLogZero, terrainRegionBase, mapInfo.minCoords, mapInfo.maxCoords, mapInfo.sizeX, mapInfo.sizeY);
-
-            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateOrCreateTerrain:UpdateExisting", delegate()
+            // There is already a terrain in this spot. Free the old and build the new.
+            DetailLog("{0},UpdateTerrain:UpdateExisting,call,id={1},base={2},minC={3},maxC={4}",
+                            BSScene.DetailLogZero, id, terrainRegionBase, minCoords, minCoords);
+
+            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateTerrain:UpdateExisting", delegate()
             {
-                if (MegaRegionParentPhysicsScene != null)
+                // Remove old terrain from the collection
+                m_terrains.Remove(terrainRegionBase);
+                // Release any physical memory it may be using.
+                terrainPhys.Dispose();
+
+                if (MegaRegionParentPhysicsScene == null)
+                {
+                    BSTerrainPhys newTerrainPhys = BuildPhysicalTerrain(terrainRegionBase, id, heightMap, minCoords, maxCoords);
+                    m_terrains.Add(terrainRegionBase, newTerrainPhys);
+
+                    m_terrainModified = true;
+                }
+                else
                 {
                     // It's possible that Combine() was called after this code was queued.
                     // If we are a child of combined regions, we don't create any terrain for us.
-                    DetailLog("{0},UpdateOrCreateTerrain:AmACombineChild,taint", BSScene.DetailLogZero);
+                    DetailLog("{0},BSTerrainManager.UpdateTerrain:AmACombineChild,taint", BSScene.DetailLogZero);
 
                     // Get rid of any terrain that may have been allocated for us.
                     ReleaseGroundPlaneAndTerrain();
@@ -252,91 +271,6 @@ public sealed class BSTerrainManager
                     // I hate doing this, but just bail
                     return;
                 }
-
-                if (mapInfo.terrainBody.ptr != IntPtr.Zero)
-                {
-                    // Updating an existing terrain.
-                    DetailLog("{0},UpdateOrCreateTerrain:UpdateExisting,taint,terrainBase={1},minC={2}, maxC={3}, szX={4}, szY={5}",
-                                    BSScene.DetailLogZero, terrainRegionBase, mapInfo.minCoords, mapInfo.maxCoords, mapInfo.sizeX, mapInfo.sizeY);
-
-                    // Remove from the dynamics world because we're going to mangle this object
-                    BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
-
-                    // Get rid of the old terrain
-                    BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
-                    BulletSimAPI.ReleaseHeightMapInfo2(mapInfo.Ptr);
-                    mapInfo.Ptr = IntPtr.Zero;
-
-                    /*
-                    // NOTE: This routine is half here because I can't get the terrain shape replacement
-                    //   to work. In the short term, the above three lines completely delete the old
-                    //   terrain and the code below recreates one from scratch.
-                    // Hopefully the Bullet community will help me out on this one.
-
-                    // First, release the old collision shape (there is only one terrain)
-                    BulletSimAPI.DeleteCollisionShape2(m_physicsScene.World.Ptr, mapInfo.terrainShape.Ptr);
-
-                    // Fill the existing height map info with the new location and size information
-                    BulletSimAPI.FillHeightMapInfo2(m_physicsScene.World.Ptr, mapInfo.Ptr, mapInfo.ID,
-                                    mapInfo.minCoords, mapInfo.maxCoords, mapInfo.heightMap, TERRAIN_COLLISION_MARGIN);
-
-                    // Create a terrain shape based on the new info
-                    mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(mapInfo.Ptr));
-
-                    // Stuff the shape into the existing terrain body
-                    BulletSimAPI.SetBodyShape2(m_physicsScene.World.Ptr, mapInfo.terrainBody.Ptr, mapInfo.terrainShape.Ptr);
-                    */
-                }
-                // else
-                {
-                    // Creating a new terrain.
-                    DetailLog("{0},UpdateOrCreateTerrain:CreateNewTerrain,taint,baseX={1},baseY={2},minZ={3},maxZ={4}",
-                                    BSScene.DetailLogZero, mapInfo.minCoords.X, mapInfo.minCoords.Y, minZ, maxZ);
-
-                    mapInfo.ID = id;
-                    mapInfo.Ptr = BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, mapInfo.ID,
-                        mapInfo.minCoords, mapInfo.maxCoords, mapInfo.heightMap, TERRAIN_COLLISION_MARGIN);
-
-                    // Create the terrain shape from the mapInfo
-                    mapInfo.terrainShape = new BulletShape(BulletSimAPI.CreateTerrainShape2(mapInfo.Ptr),
-                                ShapeData.PhysicsShapeType.SHAPE_TERRAIN);
-
-                    // The terrain object initial position is at the center of the object
-                    Vector3 centerPos;
-                    centerPos.X = minCoords.X + (mapInfo.sizeX / 2f);
-                    centerPos.Y = minCoords.Y + (mapInfo.sizeY / 2f);
-                    centerPos.Z = minZ + ((maxZ - minZ) / 2f);
-
-                    mapInfo.terrainBody = new BulletBody(mapInfo.ID,
-                            BulletSimAPI.CreateBodyWithDefaultMotionState2(mapInfo.terrainShape.ptr,
-                                                        id, centerPos, Quaternion.Identity));
-                }
-
-                // Make sure the entry is in the heightmap table
-                m_heightMaps[terrainRegionBase] = mapInfo;
-
-                // Set current terrain attributes
-                BulletSimAPI.SetFriction2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainFriction);
-                BulletSimAPI.SetHitFraction2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainHitFraction);
-                BulletSimAPI.SetRestitution2(mapInfo.terrainBody.ptr, PhysicsScene.Params.terrainRestitution);
-                BulletSimAPI.SetCollisionFlags2(mapInfo.terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
-
-                // Return the new terrain to the world of physical objects
-                BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
-
-                // redo its bounding box now that it is in the world
-                BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, mapInfo.terrainBody.ptr);
-
-                BulletSimAPI.SetCollisionFilterMask2(mapInfo.terrainBody.ptr,
-                                    (uint)CollisionFilterGroups.TerrainFilter,
-                                    (uint)CollisionFilterGroups.TerrainMask);
-
-                // Make sure the new shape is processed.
-                // BulletSimAPI.Activate2(mapInfo.terrainBody.ptr, true);
-                // BulletSimAPI.ForceActivationState2(mapInfo.terrainBody.ptr, ActivationState.ISLAND_SLEEPING);
-                BulletSimAPI.ForceActivationState2(mapInfo.terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
-
-                m_terrainModified = true;
             });
         }
         else
@@ -353,34 +287,51 @@ public sealed class BSTerrainManager
             Vector3 minCoordsX = minCoords;
             Vector3 maxCoordsX = maxCoords;
 
-            DetailLog("{0},UpdateOrCreateTerrain:NewTerrain,call,id={1}, minC={2}, maxC={3}",
+            DetailLog("{0},UpdateTerrain:NewTerrain,call,id={1}, minC={2}, maxC={3}",
                             BSScene.DetailLogZero, newTerrainID, minCoords, minCoords);
 
             // Code that must happen at taint-time
-            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateOrCreateTerrain:NewTerrain", delegate()
+            PhysicsScene.TaintedObject(inTaintTime, "BSScene.UpdateTerrain:NewTerrain", delegate()
             {
-                DetailLog("{0},UpdateOrCreateTerrain:NewTerrain,taint,baseX={1},baseY={2}", BSScene.DetailLogZero, minCoords.X, minCoords.Y);
-                // Create a new mapInfo that will be filled with the new info
-                mapInfo = new BulletHeightMapInfo(id, heightMapX,
-                        BulletSimAPI.CreateHeightMapInfo2(PhysicsScene.World.ptr, newTerrainID,
-                                    minCoordsX, maxCoordsX, heightMapX, TERRAIN_COLLISION_MARGIN));
-                // Put the unfilled heightmap info into the collection of same
-                m_heightMaps.Add(terrainRegionBase, mapInfo);
-                // Build the terrain
-                UpdateOrCreateTerrain(newTerrainID, heightMap, minCoords, maxCoords, true);
+                DetailLog("{0},UpdateTerrain:NewTerrain,taint,baseX={1},baseY={2}", 
+                                            BSScene.DetailLogZero, minCoordsX.X, minCoordsX.Y);
+                BSTerrainPhys newTerrainPhys = BuildPhysicalTerrain(terrainRegionBase, id, heightMap, minCoords, maxCoords);
+                m_terrains.Add(terrainRegionBase, newTerrainPhys);
 
                 m_terrainModified = true;
             });
         }
     }
 
-    // Someday we will have complex terrain with caves and tunnels
-    public float GetTerrainHeightAtXYZ(Vector3 loc)
+    // TODO: redo terrain implementation selection to allow other base types than heightMap.
+    private BSTerrainPhys BuildPhysicalTerrain(Vector3 terrainRegionBase, uint id, float[] heightMap, Vector3 minCoords, Vector3 maxCoords)
     {
-        // For the moment, it's flat and convex
-        return GetTerrainHeightAtXY(loc.X, loc.Y);
+        PhysicsScene.Logger.DebugFormat("{0} Terrain for {1}/{2} created with {3}", 
+                                            LogHeader, PhysicsScene.RegionName, terrainRegionBase, 
+                                            (BSTerrainPhys.TerrainImplementation)PhysicsScene.Params.terrainImplementation);
+        BSTerrainPhys newTerrainPhys = null;
+        switch ((int)PhysicsScene.Params.terrainImplementation)
+        {
+            case (int)BSTerrainPhys.TerrainImplementation.Heightmap:
+                newTerrainPhys = new BSTerrainHeightmap(PhysicsScene, terrainRegionBase, id,
+                                            heightMap, minCoords, maxCoords);
+                break;
+            case (int)BSTerrainPhys.TerrainImplementation.Mesh:
+                newTerrainPhys = new BSTerrainMesh(PhysicsScene, terrainRegionBase, id,
+                                            heightMap, minCoords, maxCoords);
+                break;
+            default:
+                PhysicsScene.Logger.ErrorFormat("{0} Bad terrain implementation specified. Type={1}/{2},Region={3}/{4}",
+                                            LogHeader, 
+                                            (int)PhysicsScene.Params.terrainImplementation, 
+                                            PhysicsScene.Params.terrainImplementation,
+                                            PhysicsScene.RegionName, terrainRegionBase);
+                break;
+        }
+        return newTerrainPhys;
     }
 
+
     // Given an X and Y, find the height of the terrain.
     // Since we could be handling multiple terrains for a mega-region,
     //    the base of the region is calcuated assuming all regions are
@@ -390,8 +341,10 @@ public sealed class BSTerrainManager
     private float lastHeightTX = 999999f;
     private float lastHeightTY = 999999f;
     private float lastHeight = HEIGHT_INITIAL_LASTHEIGHT;
-    private float GetTerrainHeightAtXY(float tX, float tY)
+    public float GetTerrainHeightAtXYZ(Vector3 loc)
     {
+        float tX = loc.X;
+        float tY = loc.Y;
         // You'd be surprized at the number of times this routine is called
         //    with the same parameters as last time.
         if (!m_terrainModified && lastHeightTX == tX && lastHeightTY == tY)
@@ -403,27 +356,14 @@ public sealed class BSTerrainManager
 
         int offsetX = ((int)(tX / (int)DefaultRegionSize.X)) * (int)DefaultRegionSize.X;
         int offsetY = ((int)(tY / (int)DefaultRegionSize.Y)) * (int)DefaultRegionSize.Y;
-        Vector2 terrainBaseXY = new Vector2(offsetX, offsetY);
+        Vector3 terrainBaseXYZ = new Vector3(offsetX, offsetY, 0f);
 
-        BulletHeightMapInfo mapInfo;
-        if (m_heightMaps.TryGetValue(terrainBaseXY, out mapInfo))
+        BSTerrainPhys physTerrain;
+        if (m_terrains.TryGetValue(terrainBaseXYZ, out physTerrain))
         {
-            float regionX = tX - offsetX;
-            float regionY = tY - offsetY;
-            int mapIndex = (int)regionY * (int)mapInfo.sizeY + (int)regionX;
-            try
-            {
-                ret = mapInfo.heightMap[mapIndex];
-            }
-            catch
-            {
-                // Sometimes they give us wonky values of X and Y. Give a warning and return something.
-                PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, x={2}, y={3}",
-                                    LogHeader, terrainBaseXY, regionX, regionY);
-                ret = HEIGHT_GETHEIGHT_RET;
-            }
-            // DetailLog("{0},BSTerrainManager.GetTerrainHeightAtXY,bX={1},baseY={2},szX={3},szY={4},regX={5},regY={6},index={7},ht={8}",
-            //         BSScene.DetailLogZero, offsetX, offsetY, mapInfo.sizeX, mapInfo.sizeY, regionX, regionY, mapIndex, ret);
+            ret = physTerrain.GetHeightAtXYZ(loc - terrainBaseXYZ);
+            DetailLog("{0},BSTerrainManager.GetTerrainHeightAtXYZ,loc={1},base={2},height={3}",
+                                             BSScene.DetailLogZero, loc, terrainBaseXYZ, ret);
         }
         else
         {
@@ -466,7 +406,7 @@ public sealed class BSTerrainManager
     // Unhook all the combining that I know about.
     public void UnCombine(PhysicsScene pScene)
     {
-        // Just like ODE, for the moment a NOP
+        // Just like ODE, we don't do anything yet.
         DetailLog("{0},BSTerrainManager.UnCombine", BSScene.DetailLogZero);
     }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
new file mode 100755
index 0000000..3279b6f
--- /dev/null
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
@@ -0,0 +1,256 @@
+/*
+ * 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 OpenSim.Framework;
+using OpenSim.Region.Framework;
+using OpenSim.Region.CoreModules;
+using OpenSim.Region.Physics.Manager;
+
+using Nini.Config;
+using log4net;
+
+using OpenMetaverse;
+
+namespace OpenSim.Region.Physics.BulletSPlugin
+{
+public sealed class BSTerrainMesh : BSTerrainPhys
+{
+    static string LogHeader = "[BULLETSIM TERRAIN MESH]";
+
+    private float[] m_savedHeightMap;
+    int m_sizeX;
+    int m_sizeY;
+
+    BulletShape m_terrainShape;
+    BulletBody m_terrainBody;
+
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, Vector3 regionSize) 
+        : base(physicsScene, regionBase, id)
+    {
+    }
+
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id /* parameters for making mesh */)
+        : base(physicsScene, regionBase, id)
+    {
+    }
+
+    // Create terrain mesh from a heightmap.
+    public BSTerrainMesh(BSScene physicsScene, Vector3 regionBase, uint id, float[] initialMap, 
+                                                    Vector3 minCoords, Vector3 maxCoords)
+        : base(physicsScene, regionBase, id)
+    {
+        int indicesCount;
+        int[] indices;
+        int verticesCount;
+        float[] vertices;
+
+        m_savedHeightMap = initialMap;
+
+        m_sizeX = (int)(maxCoords.X - minCoords.X);
+        m_sizeY = (int)(maxCoords.Y - minCoords.Y);
+
+        if (!BSTerrainMesh.ConvertHeightmapToMesh(PhysicsScene, initialMap,
+                            m_sizeX, m_sizeY,
+                            (float)m_sizeX, (float)m_sizeY,
+                            Vector3.Zero, 1.0f,
+                            out indicesCount, out indices, out verticesCount, out vertices))
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedConversionOfHeightmap", ID);
+            PhysicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+
+        m_terrainShape = new BulletShape(BulletSimAPI.CreateMeshShape2(PhysicsScene.World.ptr,
+                                        indicesCount, indices, verticesCount, vertices),
+                                        PhysicsShapeType.SHAPE_MESH);
+        if (m_terrainShape.ptr == IntPtr.Zero)
+        {
+            // DISASTER!!
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedCreationOfShape", ID);
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain mesh! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+
+        Vector3 pos = regionBase;
+        Quaternion rot = Quaternion.Identity;
+
+        m_terrainBody = new BulletBody(id, BulletSimAPI.CreateBodyWithDefaultMotionState2( m_terrainShape.ptr, ID, pos, rot));
+        if (m_terrainBody.ptr == IntPtr.Zero)
+        {
+            // DISASTER!!
+            physicsScene.Logger.ErrorFormat("{0} Failed creation of terrain body! base={1}", LogHeader, TerrainBase);
+            // Something is very messed up and a crash is in our future.
+            return;
+        }
+
+        // Set current terrain attributes
+        BulletSimAPI.SetFriction2(m_terrainBody.ptr, PhysicsScene.Params.terrainFriction);
+        BulletSimAPI.SetHitFraction2(m_terrainBody.ptr, PhysicsScene.Params.terrainHitFraction);
+        BulletSimAPI.SetRestitution2(m_terrainBody.ptr, PhysicsScene.Params.terrainRestitution);
+        BulletSimAPI.SetCollisionFlags2(m_terrainBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
+
+        // Static objects are not very massive.
+        BulletSimAPI.SetMassProps2(m_terrainBody.ptr, 0f, Vector3.Zero);
+
+        // Return the new terrain to the world of physical objects
+        BulletSimAPI.AddObjectToWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+
+        // redo its bounding box now that it is in the world
+        BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+
+        BulletSimAPI.SetCollisionFilterMask2(m_terrainBody.ptr,
+                            (uint)CollisionFilterGroups.TerrainFilter,
+                            (uint)CollisionFilterGroups.TerrainMask);
+
+        // Make it so the terrain will not move or be considered for movement.
+        BulletSimAPI.ForceActivationState2(m_terrainBody.ptr, ActivationState.DISABLE_SIMULATION);
+    }
+
+    public override void Dispose()
+    {
+        if (m_terrainBody.ptr != IntPtr.Zero)
+        {
+            BulletSimAPI.RemoveObjectFromWorld2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+            // Frees both the body and the shape.
+            BulletSimAPI.DestroyObject2(PhysicsScene.World.ptr, m_terrainBody.ptr);
+        }
+    }
+
+    public override float GetHeightAtXYZ(Vector3 pos)
+    {
+        // For the moment use the saved heightmap to get the terrain height.
+        // TODO: raycast downward to find the true terrain below the position.
+        float ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+
+        int mapIndex = (int)pos.Y * m_sizeY + (int)pos.X;
+        try
+        {
+            ret = m_savedHeightMap[mapIndex];
+        }
+        catch
+        {
+            // Sometimes they give us wonky values of X and Y. Give a warning and return something.
+            PhysicsScene.Logger.WarnFormat("{0} Bad request for terrain height. terrainBase={1}, pos={2}",
+                                                LogHeader, TerrainBase, pos);
+            ret = BSTerrainManager.HEIGHT_GETHEIGHT_RET;
+        }
+        return ret;
+    }
+
+    // Convert the passed heightmap to mesh information suitable for CreateMeshShape2().
+    // Return 'true' if successfully created.
+    public static bool ConvertHeightmapToMesh(
+                                BSScene physicsScene,
+                                float[] heightMap, int sizeX, int sizeY,    // parameters of incoming heightmap
+                                float extentX, float extentY,               // zero based range for output vertices
+                                Vector3 extentBase,                         // base to be added to all vertices
+                                float magnification,                        // number of vertices to create between heightMap coords
+                                out int indicesCountO, out int[] indicesO,
+                                out int verticesCountO, out float[] verticesO)
+    {
+        bool ret = false;
+
+        int indicesCount = 0;
+        int verticesCount = 0;
+        int[] indices = new int[0];
+        float[] vertices = new float[0];
+
+        // Simple mesh creation which assumes magnification == 1.
+        // TODO: do a more general solution that scales, adds new vertices and smoothes the result.
+
+        try
+        {
+            // One vertice per heightmap value plus the vertices off the top and bottom edge.
+            int totalVertices = (sizeX + 1) * (sizeY + 1);
+            vertices = new float[totalVertices * 3];
+            int totalIndices = sizeX * sizeY * 6;
+            indices = new int[totalIndices];
+
+            float magX = (float)sizeX / extentX;
+            float magY = (float)sizeY / extentY;
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,totVert={1},totInd={2},extentBase={3},magX={4},magY={5}",
+                                    BSScene.DetailLogZero, totalVertices, totalIndices, extentBase, magX, magY);
+            // Note that sizeX+1 vertices are created since there is land between this and the next region.
+            for (int yy = 0; yy <= sizeY; yy++)
+            {
+                for (int xx = 0; xx <= sizeX; xx++)     // Hint: the "<=" means we got through sizeX + 1 times
+                {
+                    int offset = yy * sizeX + xx;
+                    // Extend the height from the height from the last row or column
+                    if (yy == sizeY) offset -= sizeX;
+                    if (xx == sizeX) offset -= 1;
+                    float height = heightMap[offset];
+                    vertices[verticesCount + 0] = (float)xx * magX + extentBase.X;
+                    vertices[verticesCount + 1] = (float)yy * magY + extentBase.Y;
+                    vertices[verticesCount + 2] = height + extentBase.Z;
+                    verticesCount += 3;
+                }
+            }
+            verticesCount = verticesCount / 3;
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeVerts,verCount={1}", 
+                                            BSScene.DetailLogZero, verticesCount);
+
+            for (int yy = 0; yy < sizeY; yy++)
+            {
+                for (int xx = 0; xx < sizeX; xx++)
+                {
+                    int offset = yy * sizeX + xx;
+                    // Each vertices is presumed to be the upper left corner of a box of two triangles
+                    indices[indicesCount + 0] = offset;
+                    indices[indicesCount + 1] = offset + 1;
+                    indices[indicesCount + 2] = offset + sizeX + 1; // accounting for the extra column
+                    indices[indicesCount + 3] = offset + 1;
+                    indices[indicesCount + 4] = offset + sizeX + 2;
+                    indices[indicesCount + 5] = offset + sizeX + 1;
+                    indicesCount += 6;
+                }
+            }
+            physicsScene.DetailLog("{0},BSTerrainMesh.ConvertHeightMapToMesh,completeIndices,indCount={1}",   // DEEBUG DEBUG DEBUG
+                                                        LogHeader, indicesCount);                        // DEBUG
+            ret = true;
+        }
+        catch (Exception e)
+        {
+            physicsScene.Logger.ErrorFormat("{0} Failed conversion of heightmap to mesh. For={1}/{2}, e={3}",
+                                                LogHeader, physicsScene.RegionName, extentBase, e);
+        }
+
+        indicesCountO = indicesCount;
+        indicesO = indices;
+        verticesCountO = verticesCount;
+        verticesO = vertices;
+
+        return ret;
+    }
+}
+}
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
index 28fae13..4647c2d 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BulletSimAPI.cs
@@ -88,11 +88,11 @@ public struct BulletShape
     public BulletShape(IntPtr xx)
     {
         ptr = xx;
-        type=ShapeData.PhysicsShapeType.SHAPE_UNKNOWN;
-        shapeKey = 0;
+        type=PhysicsShapeType.SHAPE_UNKNOWN;
+        shapeKey = (System.UInt64)FixedShapeKey.KEY_NONE;
         isNativeShape = false;
     }
-    public BulletShape(IntPtr xx, ShapeData.PhysicsShapeType typ)
+    public BulletShape(IntPtr xx, PhysicsShapeType typ)
     {
         ptr = xx;
         type = typ;
@@ -100,7 +100,7 @@ public struct BulletShape
         isNativeShape = false;
     }
     public IntPtr ptr;
-    public ShapeData.PhysicsShapeType type;
+    public PhysicsShapeType type;
     public System.UInt64 shapeKey;
     public bool isNativeShape;
     public override string ToString()
@@ -152,7 +152,7 @@ public class BulletHeightMapInfo
         ID = id;
         Ptr = xx;
         heightMap = hm;
-        terrainRegionBase = new Vector2(0f, 0f);
+        terrainRegionBase = Vector3.Zero;
         minCoords = new Vector3(100f, 100f, 25f);
         maxCoords = new Vector3(101f, 101f, 26f);
         minZ = maxZ = 0f;
@@ -161,7 +161,7 @@ public class BulletHeightMapInfo
     public uint ID;
     public IntPtr Ptr;
     public float[] heightMap;
-    public Vector2 terrainRegionBase;
+    public Vector3 terrainRegionBase;
     public Vector3 minCoords;
     public Vector3 maxCoords;
     public float sizeX, sizeY;
@@ -178,24 +178,37 @@ public struct ConvexHull
         int VertexCount;
         Vector3[] Vertices;
 }
+public enum PhysicsShapeType
+{
+        SHAPE_UNKNOWN   = 0,
+        SHAPE_CAPSULE   = 1,
+        SHAPE_BOX       = 2,
+        SHAPE_CONE      = 3,
+        SHAPE_CYLINDER  = 4,
+        SHAPE_SPHERE    = 5,
+        SHAPE_MESH      = 6,
+        SHAPE_HULL      = 7,
+    // following defined by BulletSim
+        SHAPE_GROUNDPLANE  = 20,
+        SHAPE_TERRAIN   = 21,
+        SHAPE_COMPOUND  = 22,
+        SHAPE_HEIGHTMAP = 23,
+};
+
+// The native shapes have predefined shape hash keys
+public enum FixedShapeKey : ulong
+{
+    KEY_NONE        = 0,
+    KEY_BOX         = 1,
+    KEY_SPHERE      = 2,
+    KEY_CONE        = 3,
+    KEY_CYLINDER    = 4,
+    KEY_CAPSULE     = 5,
+}
+
 [StructLayout(LayoutKind.Sequential)]
 public struct ShapeData
 {
-    public enum PhysicsShapeType
-    {
-                SHAPE_UNKNOWN   = 0,
-                SHAPE_AVATAR    = 1,
-                SHAPE_BOX       = 2,
-                SHAPE_CONE      = 3,
-                SHAPE_CYLINDER  = 4,
-                SHAPE_SPHERE    = 5,
-                SHAPE_MESH      = 6,
-                SHAPE_HULL      = 7,
-        // following defined by BulletSim
-                SHAPE_GROUNDPLANE  = 20,
-                SHAPE_TERRAIN   = 21,
-                SHAPE_COMPOUND  = 22,
-    };
     public uint ID;
     public PhysicsShapeType Type;
     public Vector3 Position;
@@ -216,16 +229,6 @@ public struct ShapeData
     // note that bools are passed as floats since bool size changes by language and architecture
     public const float numericTrue = 1f;
     public const float numericFalse = 0f;
-
-    // The native shapes have predefined shape hash keys
-    public enum FixedShapeKey : ulong
-    {
-        KEY_BOX         = 1,
-        KEY_SPHERE      = 2,
-        KEY_CONE        = 3,
-        KEY_CYLINDER    = 4,
-        KEY_CAPSULE     = 5,
-    }
 }
 [StructLayout(LayoutKind.Sequential)]
 public struct SweepHit
@@ -280,6 +283,7 @@ public struct ConfigurationParameters
         public float ccdSweptSphereRadius;
     public float contactProcessingThreshold;
 
+    public float terrainImplementation;
     public float terrainFriction;
     public float terrainHitFraction;
     public float terrainRestitution;
@@ -287,7 +291,8 @@ public struct ConfigurationParameters
     public float avatarStandingFriction;
     public float avatarDensity;
     public float avatarRestitution;
-    public float avatarCapsuleRadius;
+    public float avatarCapsuleWidth;
+    public float avatarCapsuleDepth;
     public float avatarCapsuleHeight;
         public float avatarContactProcessingThreshold;
 
@@ -388,13 +393,13 @@ public enum CollisionFilterGroups : uint
     ObjectFilter            = BSolidFilter,
     ObjectMask              = BAllFilter,
     StaticObjectFilter      = BStaticFilter,
-    StaticObjectMask        = BAllFilter,
+    StaticObjectMask        = BAllFilter & ~BStaticFilter,   // static objects don't collide with each other
     LinksetFilter           = BLinksetFilter,
-    LinksetMask             = BAllFilter & ~BLinksetFilter,
+    LinksetMask             = BAllFilter & ~BLinksetFilter, // linkset objects don't collide with each other
     VolumeDetectFilter      = BSensorTrigger,
     VolumeDetectMask        = ~BSensorTrigger,
     TerrainFilter           = BTerrainFilter,
-    TerrainMask             = BAllFilter & ~BStaticFilter,
+    TerrainMask             = BAllFilter & ~BStaticFilter,  // static objects on the ground don't collide
     GroundPlaneFilter       = BGroundPlaneFilter,
     GroundPlaneMask         = BAllFilter