9 files changed, 270 insertions, 111 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
index e208d3a..90c2d9c 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs
@@ -479,7 +479,7 @@ public sealed class BSCharacter : BSPhysObject
             // The character is out of the known/simulated area.
             // Force the avatar position to be within known. ScenePresence will use the position
             //    plus the velocity to decide if the avatar is moving out of the region.
-            RawPosition = PhysicsScene.TerrainManager.ClampPositionIntoKnownTerrain(RawPosition);

+            RawPosition = PhysicsScene.TerrainManager.ClampPositionIntoKnownTerrain(RawPosition);
             DetailLog("{0},BSCharacter.PositionSanityCheck,notWithinKnownTerrain,clampedPos={1}", LocalID, RawPosition);
             return true;
         }
@@ -898,7 +898,7 @@ public sealed class BSCharacter : BSPhysObject
         // Do some sanity checking for the avatar. Make sure it's above ground and inbounds.
         if (PositionSanityCheck(true))
         {
-            DetailLog("{0},BSCharacter.UpdateProperties,updatePosForSanity,pos={1}", LocalID, _position);

+            DetailLog("{0},BSCharacter.UpdateProperties,updatePosForSanity,pos={1}", LocalID, _position);
             entprop.Position = _position;
         }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
index 5549984..65df741 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSDynamics.cs
@@ -321,7 +321,7 @@ namespace OpenSim.Region.Physics.BulletSPlugin
             }
         }
 
-        internal void ProcessTypeChange(Vehicle pType)
+        public void ProcessTypeChange(Vehicle pType)
         {
             VDetailLog("{0},ProcessTypeChange,type={1}", Prim.LocalID, pType);
             // Set Defaults For Type
@@ -1301,14 +1301,52 @@ namespace OpenSim.Region.Physics.BulletSPlugin
         //      efficiency of 1.0 will cause the spring to reach its equilibrium with exponential decay.
         public void ComputeAngularVerticalAttraction()
         {
+
             // If vertical attaction timescale is reasonable
             if (enableAngularVerticalAttraction && m_verticalAttractionTimescale < m_verticalAttractionCutoff)
             {
+                // Possible solution derived from a discussion at:
+                // http://stackoverflow.com/questions/14939657/computing-vector-from-quaternion-works-computing-quaternion-from-vector-does-no
+
+                // Create a rotation that is only the vehicle's rotation around Z
+                Vector3 currentEuler = Vector3.Zero;
+                VehicleOrientation.GetEulerAngles(out currentEuler.X, out currentEuler.Y, out currentEuler.Z);
+                Quaternion justZOrientation = Quaternion.CreateFromAxisAngle(Vector3.UnitZ, currentEuler.Z);
+
+                // Create the axis that is perpendicular to the up vector and the rotated up vector.
+                Vector3 differenceAxis = Vector3.Cross(Vector3.UnitZ * justZOrientation, Vector3.UnitZ * VehicleOrientation);
+                // Compute the angle between those to vectors.
+                double differenceAngle = Math.Acos((double)Vector3.Dot(Vector3.UnitZ, Vector3.Normalize(Vector3.UnitZ * VehicleOrientation)));
+                // 'differenceAngle' is the angle to rotate and 'differenceAxis' is the plane to rotate in to get the vehicle vertical
+
+                // Reduce the change by the time period it is to change in. Timestep is handled when velocity is applied.
+                // TODO: add 'efficiency'.
+                differenceAngle /= m_verticalAttractionTimescale;
+
+                // Create the quaterian representing the correction angle
+                Quaternion correctionRotation = Quaternion.CreateFromAxisAngle(differenceAxis, (float)differenceAngle);
+
+                // Turn that quaternion into Euler values to make it into velocities to apply.
+                Vector3 vertContributionV = Vector3.Zero;
+                correctionRotation.GetEulerAngles(out vertContributionV.X, out vertContributionV.Y, out vertContributionV.Z);
+                vertContributionV *= -1f;
+
+                VehicleRotationalVelocity += vertContributionV;
+
+                VDetailLog("{0},  MoveAngular,verticalAttraction,diffAxis={1},diffAng={2},corrRot={3},contrib={4}",
+                                Prim.LocalID,
+                                differenceAxis,
+                                differenceAngle,
+                                correctionRotation,
+                                vertContributionV);
+
+                // ===================================================================
+                /*
                 Vector3 vertContributionV = Vector3.Zero;
                 Vector3 origRotVelW = VehicleRotationalVelocity;        // DEBUG DEBUG
 
                 // Take a vector pointing up and convert it from world to vehicle relative coords.
-                Vector3 verticalError = Vector3.UnitZ * VehicleOrientation;
+                Vector3 verticalError = Vector3.Normalize(Vector3.UnitZ * VehicleOrientation);
 
                 // If vertical attraction correction is needed, the vector that was pointing up (UnitZ)
                 //    is now:
@@ -1334,13 +1372,17 @@ namespace OpenSim.Region.Physics.BulletSPlugin
                 // 'vertContrbution' is now the necessary angular correction to correct tilt in one second.
                 //     Correction happens over a number of seconds.
                 Vector3 unscaledContribVerticalErrorV = vertContributionV;     // DEBUG DEBUG
+
+                // The correction happens over the user's time period
                 vertContributionV /= m_verticalAttractionTimescale;
 
-                VehicleRotationalVelocity += vertContributionV;
+                // Rotate the vehicle rotation to the world coordinates.
+                VehicleRotationalVelocity += (vertContributionV * VehicleOrientation);
 
                 VDetailLog("{0},  MoveAngular,verticalAttraction,,origRotVW={1},vertError={2},unscaledV={3},eff={4},ts={5},vertContribV={6}",
                                 Prim.LocalID, origRotVelW, verticalError, unscaledContribVerticalErrorV, 
                                 m_verticalAttractionEfficiency, m_verticalAttractionTimescale, vertContributionV);
+                */
             }
         }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs b/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs
index 92d62ff..ee77d6e 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSMaterials.cs
@@ -180,11 +180,14 @@ public static class BSMaterials
     // Use reflection to set the value in the attribute structure.
     private static void SetAttributeValue(int matType, string attribName, float val)
     {
+        // Get the current attribute values for this material
         MaterialAttributes thisAttrib = Attributes[matType];
+        // Find the field for the passed attribute name (eg, find field named 'friction')
         FieldInfo fieldInfo = thisAttrib.GetType().GetField(attribName.ToLower());
         if (fieldInfo != null)
         {
             fieldInfo.SetValue(thisAttrib, val);
+            // Copy new attributes back to array -- since MaterialAttributes is 'struct', passed by value, not reference.
             Attributes[matType] = thisAttrib;
         }
     }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
index 4d89a88..385ed9e 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
@@ -142,6 +142,14 @@ public static class BSParam
     public static float VehicleAngularBankingTimescaleFudge { get; private set; }
     public static bool VehicleDebuggingEnabled { get; private set; }
 
+    // Convex Hulls
+    public static int CSHullMaxDepthSplit { get; private set; }
+    public static int CSHullMaxDepthSplitForSimpleShapes { get; private set; }
+    public static float CSHullConcavityThresholdPercent { get; private set; }
+    public static float CSHullVolumeConservationThresholdPercent { get; private set; }
+    public static int CSHullMaxVertices { get; private set; }
+    public static float CSHullMaxSkinWidth { get; private set; }
+
     // Linkset implementation parameters
     public static float LinksetImplementation { get; private set; }
     public static bool LinkConstraintUseFrameOffset { get; private set; }
@@ -195,10 +203,10 @@ public static class BSParam
     public delegate void PSetOnObject<T>(BSScene scene, BSPhysObject obj);
     public sealed class ParameterDefn<T> : ParameterDefnBase
     {
-        T defaultValue;
-        PSetValue<T> setter;
-        PGetValue<T> getter;
-        PSetOnObject<T> objectSet;
+        private T defaultValue;
+        private PSetValue<T> setter;
+        private PGetValue<T> getter;
+        private PSetOnObject<T> objectSet;
         public ParameterDefn(string pName, string pDesc, T pDefault, PGetValue<T> pGetter, PSetValue<T> pSetter)
             : base(pName, pDesc)
         {
@@ -215,13 +223,23 @@ public static class BSParam
             getter = pGetter;
             objectSet = pObjSetter;
         }
+        /* Wish I could simplify using this definition but CLR doesn't store references so closure around delegates of references won't work
+        public ParameterDefn(string pName, string pDesc, T pDefault, ref T loc)
+            : base(pName, pDesc)
+        {
+            defaultValue = pDefault;
+            setter = (s, v) => { loc = v; };
+            getter = (s) => { return loc; };
+            objectSet = null;
+        }
+         */
         public override void AssignDefault(BSScene s)
         {
             setter(s, defaultValue);
         }
         public override string GetValue(BSScene s)
         {
-            return String.Format("{0}", getter(s));
+            return getter(s).ToString();
         }
         public override void SetValue(BSScene s, string valAsString)
         {
@@ -244,6 +262,7 @@ public static class BSParam
                 try
                 {
                     T setValue = (T)parser.Invoke(genericType, new Object[] { valAsString });
+                    // Store the parsed value
                     setter(s, setValue);
                     // s.Logger.DebugFormat("{0} Parameter {1} = {2}", LogHeader, name, setValue);
                 }
@@ -463,7 +482,7 @@ public static class BSParam
             (s) => { return TerrainImplementation; },
             (s,v) => { TerrainImplementation = v; } ),
         new ParameterDefn<int>("TerrainMeshMagnification", "Number of times the 256x256 heightmap is multiplied to create the terrain mesh" ,
-            3,
+            2,
             (s) => { return TerrainMeshMagnification; },
             (s,v) => { TerrainMeshMagnification = v; } ),
         new ParameterDefn<float>("TerrainFriction", "Factor to reduce movement against terrain surface" ,
@@ -623,6 +642,31 @@ public static class BSParam
             (s) => { return GlobalContactBreakingThreshold; },
             (s,v) => { GlobalContactBreakingThreshold = v; s.UnmanagedParams[0].globalContactBreakingThreshold = v; } ),
 
+            new ParameterDefn<int>("CSHullMaxDepthSplit", "CS impl: max depth to split for hull. 1-10 but > 7 is iffy",
+            7,
+            (s) => { return CSHullMaxDepthSplit; },
+            (s,v) => { CSHullMaxDepthSplit = v; } ),
+            new ParameterDefn<int>("CSHullMaxDepthSplitForSimpleShapes", "CS impl: max depth setting for simple prim shapes",
+            2,
+            (s) => { return CSHullMaxDepthSplitForSimpleShapes; },
+            (s,v) => { CSHullMaxDepthSplitForSimpleShapes = v; } ),
+            new ParameterDefn<float>("CSHullConcavityThresholdPercent", "CS impl: concavity threshold percent (0-20)",
+            5f,
+            (s) => { return CSHullConcavityThresholdPercent; },
+            (s,v) => { CSHullConcavityThresholdPercent = v; } ),
+            new ParameterDefn<float>("CSHullVolumeConservationThresholdPercent", "percent volume conservation to collapse hulls (0-30)",
+            5f,
+            (s) => { return CSHullVolumeConservationThresholdPercent; },
+            (s,v) => { CSHullVolumeConservationThresholdPercent = v; } ),
+            new ParameterDefn<int>("CSHullMaxVertices", "CS impl: maximum number of vertices in output hulls. Keep < 50.",
+            32,
+            (s) => { return CSHullMaxVertices; },
+            (s,v) => { CSHullMaxVertices = v; } ),
+            new ParameterDefn<float>("CSHullMaxSkinWidth", "CS impl: skin width to apply to output hulls.",
+            0,
+            (s) => { return CSHullMaxSkinWidth; },
+            (s,v) => { CSHullMaxSkinWidth = v; } ),
+
             new ParameterDefn<float>("LinksetImplementation", "Type of linkset implementation (0=Constraint, 1=Compound, 2=Manual)",
             (float)BSLinkset.LinksetImplementation.Compound,
             (s) => { return LinksetImplementation; },
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
index f953c1e..6bb88c7 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs
@@ -86,7 +86,7 @@ public abstract class BSPhysObject : PhysicsActor
         PhysBody = new BulletBody(localID);
         PhysShape = new BulletShape();
 
-        LastAssetBuildFailed = false;
+        PrimAssetState = PrimAssetCondition.Unknown;
 
         // Default material type. Also sets Friction, Restitution and Density.
         SetMaterial((int)MaterialAttributes.Material.Wood);
@@ -133,9 +133,13 @@ public abstract class BSPhysObject : PhysicsActor
     // Reference to the physical shape (btCollisionShape) of this object
     public BulletShape PhysShape;
 
-    // 'true' if the mesh's underlying asset failed to build.
-    // This will keep us from looping after the first time the build failed.
-    public bool LastAssetBuildFailed { get; set; }
+    // The physical representation of the prim might require an asset fetch.
+    // The asset state is first 'Unknown' then 'Waiting' then either 'Failed' or 'Fetched'.
+    public enum PrimAssetCondition
+    {
+        Unknown, Waiting, Failed, Fetched
+    }
+    public PrimAssetCondition PrimAssetState { get; set; }
 
     // The objects base shape information. Null if not a prim type shape.
     public PrimitiveBaseShape BaseShape { get; protected set; }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 2cbbe9a..6a5461a 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -155,7 +155,7 @@ public class BSPrim : BSPhysObject
     public override PrimitiveBaseShape Shape {
         set {
             BaseShape = value;
-            LastAssetBuildFailed = false;
+            PrimAssetState = PrimAssetCondition.Unknown;
             ForceBodyShapeRebuild(false);
         }
     }
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
index 05c147d..220fbbc 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSShapeCollection.cs
@@ -447,17 +447,10 @@ public sealed class BSShapeCollection : IDisposable
 
         // If the prim attributes are simple, this could be a simple Bullet native shape
         if (!haveShape
+                && nativeShapePossible
                 && pbs != null
                 && !pbs.SculptEntry
-                && nativeShapePossible
-                && ((pbs.SculptEntry && !BSParam.ShouldMeshSculptedPrim)
-                    || (pbs.ProfileBegin == 0 && pbs.ProfileEnd == 0
-                        && pbs.ProfileHollow == 0
-                        && pbs.PathTwist == 0 && pbs.PathTwistBegin == 0
-                        && pbs.PathBegin == 0 && pbs.PathEnd == 0
-                        && pbs.PathTaperX == 0 && pbs.PathTaperY == 0
-                        && pbs.PathScaleX == 100 && pbs.PathScaleY == 100
-                        && pbs.PathShearX == 0 && pbs.PathShearY == 0) ) )
+                && ((pbs.SculptEntry && !BSParam.ShouldMeshSculptedPrim) || PrimHasNoCuts(pbs)) )
         {
             // Get the scale of any existing shape so we can see if the new shape is same native type and same size.
             OMV.Vector3 scaleOfExistingShape = OMV.Vector3.Zero;
@@ -508,6 +501,18 @@ public sealed class BSShapeCollection : IDisposable
         return ret;
     }
 
+    // return 'true' if this shape description does not include any cutting or twisting.
+    private bool PrimHasNoCuts(PrimitiveBaseShape pbs)
+    {
+        return pbs.ProfileBegin == 0 && pbs.ProfileEnd == 0
+            && pbs.ProfileHollow == 0
+            && pbs.PathTwist == 0 && pbs.PathTwistBegin == 0
+            && pbs.PathBegin == 0 && pbs.PathEnd == 0
+            && pbs.PathTaperX == 0 && pbs.PathTaperY == 0
+            && pbs.PathScaleX == 100 && pbs.PathScaleY == 100
+            && pbs.PathShearX == 0 && pbs.PathShearY == 0;
+    }
+
     // return 'true' if the prim's shape was changed.
     public bool CreateGeomMeshOrHull(BSPhysObject prim, ShapeDestructionCallback shapeCallback)
     {
@@ -518,7 +523,7 @@ public sealed class BSShapeCollection : IDisposable
         if (prim.IsPhysical && BSParam.ShouldUseHullsForPhysicalObjects)
         {
             // Update prim.BSShape to reference a hull of this shape.
-            ret = GetReferenceToHull(prim,shapeCallback);
+            ret = GetReferenceToHull(prim, shapeCallback);
             if (DDetail) DetailLog("{0},BSShapeCollection.CreateGeom,hull,shape={1},key={2}",
                                     prim.LocalID, prim.PhysShape, prim.PhysShape.shapeKey.ToString("X"));
         }
@@ -699,6 +704,7 @@ public sealed class BSShapeCollection : IDisposable
 
     // See that hull shape exists in the physical world and update prim.BSShape.
     // We could be creating the hull because scale changed or whatever.
+    // Return 'true' if a new hull was built. Otherwise, returning a shared hull instance.
     private bool GetReferenceToHull(BSPhysObject prim, ShapeDestructionCallback shapeCallback)
     {
         BulletShape newShape;
@@ -717,6 +723,7 @@ public sealed class BSShapeCollection : IDisposable
         DereferenceShape(prim.PhysShape, shapeCallback);
 
         newShape = CreatePhysicalHull(prim.PhysObjectName, newHullKey, prim.BaseShape, prim.Size, lod);
+        // It might not have been created if we're waiting for an asset.
         newShape = VerifyMeshCreated(newShape, prim);
 
         ReferenceShape(newShape);
@@ -735,13 +742,13 @@ public sealed class BSShapeCollection : IDisposable
         HullDesc hullDesc;
         if (Hulls.TryGetValue(newHullKey, out hullDesc))
         {
-            // If the hull shape already is created, just use it.
+            // If the hull shape already has been created, just use the one shared instance.
             newShape = hullDesc.shape.Clone();
         }
         else
         {
-            // Build a new hull in the physical world
-            // Pass true for physicalness as this creates some sort of bounding box which we don't need
+            // Build a new hull in the physical world.
+            // Pass true for physicalness as this prevents the creation of bounding box which is not needed
             IMesh meshData = PhysicsScene.mesher.CreateMesh(objName, pbs, size, lod, true, false, false, false);
             if (meshData != null)
             {
@@ -761,15 +768,35 @@ public sealed class BSShapeCollection : IDisposable
                     convVertices.Add(new float3(vv.X, vv.Y, vv.Z));
                 }
 
+                uint maxDepthSplit = (uint)BSParam.CSHullMaxDepthSplit;
+                if (BSParam.CSHullMaxDepthSplit != BSParam.CSHullMaxDepthSplitForSimpleShapes)
+                {
+                    // Simple primitive shapes we know are convex so they are better implemented with
+                    //    fewer hulls.
+                    // Check for simple shape (prim without cuts) and reduce split parameter if so.
+                    if (PrimHasNoCuts(pbs))
+                    {
+                        maxDepthSplit = (uint)BSParam.CSHullMaxDepthSplitForSimpleShapes;
+                    }
+                }
+
                 // setup and do convex hull conversion
                 m_hulls = new List<ConvexResult>();
                 DecompDesc dcomp = new DecompDesc();
                 dcomp.mIndices = convIndices;
                 dcomp.mVertices = convVertices;
+                dcomp.mDepth = maxDepthSplit;
+                dcomp.mCpercent = BSParam.CSHullConcavityThresholdPercent;
+                dcomp.mPpercent = BSParam.CSHullVolumeConservationThresholdPercent;
+                dcomp.mMaxVertices = (uint)BSParam.CSHullMaxVertices;
+                dcomp.mSkinWidth = BSParam.CSHullMaxSkinWidth;
                 ConvexBuilder convexBuilder = new ConvexBuilder(HullReturn);
                 // create the hull into the _hulls variable
                 convexBuilder.process(dcomp);
 
+                DetailLog("{0},BSShapeCollection.CreatePhysicalHull,key={1},inVert={2},inInd={3},split={4},hulls={5}",
+                                    BSScene.DetailLogZero, newHullKey, indices.GetLength(0), vertices.Count, maxDepthSplit, m_hulls.Count);
+
                 // Convert the vertices and indices for passing to unmanaged.
                 // The hull information is passed as a large floating point array.
                 // The format is:
@@ -904,58 +931,79 @@ public sealed class BSShapeCollection : IDisposable
         if (newShape.HasPhysicalShape)
             return newShape;
 
-        // If this mesh has an underlying asset and we have not failed getting it before, fetch the asset
-        if (prim.BaseShape.SculptEntry && !prim.LastAssetBuildFailed && prim.BaseShape.SculptTexture != OMV.UUID.Zero)
+        // VerifyMeshCreated is called after trying to create the mesh. If we think the asset had been
+        //    fetched but we end up here again, the meshing of the asset must have failed.
+        // Prevent trying to keep fetching the mesh by declaring failure.
+        if (prim.PrimAssetState == BSPhysObject.PrimAssetCondition.Fetched)
+        {
+            prim.PrimAssetState = BSPhysObject.PrimAssetCondition.Failed;
+            PhysicsScene.Logger.WarnFormat("{0} Fetched asset would not mesh. {1}, texture={2}",
+                                            LogHeader, prim.PhysObjectName, prim.BaseShape.SculptTexture);
+        }
+        else
         {
-            DetailLog("{0},BSShapeCollection.VerifyMeshCreated,fetchAsset,lastFailed={1}", prim.LocalID, prim.LastAssetBuildFailed);
-            // This will prevent looping through this code as we keep trying to get the failed shape
-            prim.LastAssetBuildFailed = true;
+            // If this mesh has an underlying asset and we have not failed getting it before, fetch the asset
+            if (prim.BaseShape.SculptEntry 
+                && prim.PrimAssetState != BSPhysObject.PrimAssetCondition.Failed
+                && prim.PrimAssetState != BSPhysObject.PrimAssetCondition.Waiting
+                && prim.BaseShape.SculptTexture != OMV.UUID.Zero
+                )
+            {
+                DetailLog("{0},BSShapeCollection.VerifyMeshCreated,fetchAsset", prim.LocalID);
+                // Multiple requestors will know we're waiting for this asset
+                prim.PrimAssetState = BSPhysObject.PrimAssetCondition.Waiting;
 
-            BSPhysObject xprim = prim;
-            Util.FireAndForget(delegate
-                {
-                    RequestAssetDelegate assetProvider = PhysicsScene.RequestAssetMethod;
-                    if (assetProvider != null)
+                BSPhysObject xprim = prim;
+                Util.FireAndForget(delegate
                     {
-                        BSPhysObject yprim = xprim; // probably not necessary, but, just in case.
-                        assetProvider(yprim.BaseShape.SculptTexture, delegate(AssetBase asset)
+                        RequestAssetDelegate assetProvider = PhysicsScene.RequestAssetMethod;
+                        if (assetProvider != null)
                         {
-                            bool assetFound = false;            // DEBUG DEBUG
-                            string mismatchIDs = String.Empty;  // DEBUG DEBUG
-                            if (asset != null && yprim.BaseShape.SculptEntry)
+                            BSPhysObject yprim = xprim; // probably not necessary, but, just in case.
+                            assetProvider(yprim.BaseShape.SculptTexture, delegate(AssetBase asset)
                             {
-                                if (yprim.BaseShape.SculptTexture.ToString() == asset.ID)
+                                bool assetFound = false;
+                                string mismatchIDs = String.Empty;  // DEBUG DEBUG
+                                if (asset != null && yprim.BaseShape.SculptEntry)
                                 {
-                                    yprim.BaseShape.SculptData = asset.Data;
-                                    // This will cause the prim to see that the filler shape is not the right
-                                    //    one and try again to build the object.
-                                    // No race condition with the normal shape setting since the rebuild is at taint time.
-                                    yprim.ForceBodyShapeRebuild(false /* inTaintTime */);
-                                    assetFound = true;
+                                    if (yprim.BaseShape.SculptTexture.ToString() == asset.ID)
+                                    {
+                                        yprim.BaseShape.SculptData = asset.Data;
+                                        // This will cause the prim to see that the filler shape is not the right
+                                        //    one and try again to build the object.
+                                        // No race condition with the normal shape setting since the rebuild is at taint time.
+                                        yprim.ForceBodyShapeRebuild(false /* inTaintTime */);
+                                        assetFound = true;
+                                    }
+                                    else
+                                    {
+                                        mismatchIDs = yprim.BaseShape.SculptTexture.ToString() + "/" + asset.ID;
+                                    }
                                 }
+                                if (assetFound)
+                                    yprim.PrimAssetState = BSPhysObject.PrimAssetCondition.Fetched;
                                 else
-                                {
-                                    mismatchIDs = yprim.BaseShape.SculptTexture.ToString() + "/" + asset.ID;
-                                }
-                            }
-                            DetailLog("{0},BSShapeCollection,fetchAssetCallback,found={1},isSculpt={2},ids={3}",
-                                        yprim.LocalID, assetFound, yprim.BaseShape.SculptEntry, mismatchIDs );
+                                    yprim.PrimAssetState = BSPhysObject.PrimAssetCondition.Failed;
+                                DetailLog("{0},BSShapeCollection,fetchAssetCallback,found={1},isSculpt={2},ids={3}",
+                                            yprim.LocalID, assetFound, yprim.BaseShape.SculptEntry, mismatchIDs );
 
-                        });
-                    }
-                    else
-                    {
-                        PhysicsScene.Logger.ErrorFormat("{0} Physical object requires asset but no asset provider. Name={1}",
-                                                    LogHeader, PhysicsScene.Name);
-                    }
-                });
-        }
-        else
-        {
-            if (prim.LastAssetBuildFailed)
+                            });
+                        }
+                        else
+                        {
+                            xprim.PrimAssetState = BSPhysObject.PrimAssetCondition.Failed;
+                            PhysicsScene.Logger.ErrorFormat("{0} Physical object requires asset but no asset provider. Name={1}",
+                                                        LogHeader, PhysicsScene.Name);
+                        }
+                    });
+            }
+            else
             {
-                PhysicsScene.Logger.ErrorFormat("{0} Mesh failed to fetch asset. lID={1}, texture={2}",
-                                            LogHeader, prim.LocalID, prim.BaseShape.SculptTexture);
+                if (prim.PrimAssetState == BSPhysObject.PrimAssetCondition.Failed)
+                {
+                    PhysicsScene.Logger.WarnFormat("{0} Mesh failed to fetch asset. obj={1}, texture={2}",
+                                                LogHeader, prim.PhysObjectName, prim.BaseShape.SculptTexture);
+                }
             }
         }
 
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
index a60946d..b2fb835 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainManager.cs
@@ -132,6 +132,7 @@ public sealed class BSTerrainManager : IDisposable
     //    safe to call Bullet in real time. We hope no one is moving prims around yet.
     public void CreateInitialGroundPlaneAndTerrain()
     {
+        DetailLog("{0},BSTerrainManager.CreateInitialGroundPlaneAndTerrain,region={1}", BSScene.DetailLogZero, PhysicsScene.RegionName);
         // The ground plane is here to catch things that are trying to drop to negative infinity
         BulletShape groundPlaneShape = PhysicsScene.PE.CreateGroundPlaneShape(BSScene.GROUNDPLANE_ID, 1f, BSParam.TerrainCollisionMargin);
         m_groundPlane = PhysicsScene.PE.CreateBodyWithDefaultMotionState(groundPlaneShape, 
@@ -145,14 +146,18 @@ public sealed class BSTerrainManager : IDisposable
         m_groundPlane.collisionType = CollisionType.Groundplane;
         m_groundPlane.ApplyCollisionMask(PhysicsScene);
 
-        // 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);
+        lock (m_terrains)
+        {
+            // Build an initial terrain and put it in the world. This quickly gets replaced by the real region terrain.
+            m_terrains.Add(Vector3.Zero, initialTerrain);
+        }
     }
 
     // Release all the terrain structures we might have allocated
     public void ReleaseGroundPlaneAndTerrain()
     {
+        DetailLog("{0},BSTerrainManager.ReleaseGroundPlaneAndTerrain,region={1}", BSScene.DetailLogZero, PhysicsScene.RegionName);
         if (m_groundPlane.HasPhysicalBody)
         {
             if (PhysicsScene.PE.RemoveObjectFromWorld(PhysicsScene.World, m_groundPlane))
@@ -193,11 +198,16 @@ public sealed class BSTerrainManager : IDisposable
                 //    the terrain is added to our parent
                 if (MegaRegionParentPhysicsScene is BSScene)
                 {
-                    DetailLog("{0},SetTerrain.ToParent,offset={1},worldMax={2}",
-                                    BSScene.DetailLogZero, m_worldOffset, m_worldMax);
-                    ((BSScene)MegaRegionParentPhysicsScene).TerrainManager.UpdateTerrain(
-                                    BSScene.CHILDTERRAIN_ID, localHeightMap, 
-                                    m_worldOffset, m_worldOffset + DefaultRegionSize, true);
+                    DetailLog("{0},SetTerrain.ToParent,offset={1},worldMax={2}", BSScene.DetailLogZero, m_worldOffset, m_worldMax);
+                    // This looks really odd but this region is passing its terrain to its mega-region root region
+                    //    and the creation of the terrain must happen on the root region's taint thread and not
+                    //    my taint thread.
+                    ((BSScene)MegaRegionParentPhysicsScene).PostTaintObject("TerrainManager.SetTerrain.Mega-" + m_worldOffset.ToString(), 0, delegate()
+                    {
+                        ((BSScene)MegaRegionParentPhysicsScene).TerrainManager.UpdateTerrain(
+                                        BSScene.CHILDTERRAIN_ID, localHeightMap,
+                                        m_worldOffset, m_worldOffset + DefaultRegionSize, true /* inTaintTime */);
+                    });
                 }
             }
             else
@@ -206,16 +216,16 @@ public sealed class BSTerrainManager : IDisposable
                 DetailLog("{0},SetTerrain.Existing", BSScene.DetailLogZero);
 
                 UpdateTerrain(BSScene.TERRAIN_ID, localHeightMap,
-                                    m_worldOffset, m_worldOffset + DefaultRegionSize, true);
+                                    m_worldOffset, m_worldOffset + DefaultRegionSize, true /* inTaintTime */);
             }
         });
     }
 
-    // If called with no mapInfo for the terrain, this will create a new mapInfo and terrain
+    // If called for terrain has has not been previously allocated, a new terrain will be built
     //     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 and there is an existing terrain body, a new
+    // If 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.)
@@ -223,8 +233,8 @@ public sealed class BSTerrainManager : IDisposable
     private void UpdateTerrain(uint id, float[] heightMap, 
                             Vector3 minCoords, Vector3 maxCoords, bool inTaintTime)
     {
-        DetailLog("{0},BSTerrainManager.UpdateTerrain,call,minC={1},maxC={2},inTaintTime={3}",
-                            BSScene.DetailLogZero, minCoords, maxCoords, inTaintTime);
+        DetailLog("{0},BSTerrainManager.UpdateTerrain,call,id={1},minC={2},maxC={3},inTaintTime={4}",
+                            BSScene.DetailLogZero, id, 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
@@ -253,7 +263,7 @@ public sealed class BSTerrainManager : IDisposable
             if (m_terrains.TryGetValue(terrainRegionBase, out terrainPhys))
             {
                 // There is already a terrain in this spot. Free the old and build the new.
-                DetailLog("{0},UpdateTerrain:UpdateExisting,call,id={1},base={2},minC={3},maxC={4}",
+                DetailLog("{0},BSTErrainManager.UpdateTerrain:UpdateExisting,call,id={1},base={2},minC={3},maxC={4}",
                                 BSScene.DetailLogZero, id, terrainRegionBase, minCoords, minCoords);
 
                 // Remove old terrain from the collection
@@ -292,7 +302,7 @@ public sealed class BSTerrainManager : IDisposable
                 if (newTerrainID >= BSScene.CHILDTERRAIN_ID)
                     newTerrainID = ++m_terrainCount;
 
-                DetailLog("{0},UpdateTerrain:NewTerrain,taint,newID={1},minCoord={2},maxCoord={3}",
+                DetailLog("{0},BSTerrainManager.UpdateTerrain:NewTerrain,taint,newID={1},minCoord={2},maxCoord={3}",
                                             BSScene.DetailLogZero, newTerrainID, minCoords, minCoords);
                 BSTerrainPhys newTerrainPhys = BuildPhysicalTerrain(terrainRegionBase, id, heightMap, minCoords, maxCoords);
                 m_terrains.Add(terrainRegionBase, newTerrainPhys);
@@ -343,37 +353,35 @@ public sealed class BSTerrainManager : IDisposable
     {
         Vector3 ret = pPos;
 
+        // First, base addresses are never negative so correct for that possible problem.
+        if (ret.X < 0f || ret.Y < 0f)
+        {
+            ret.X = Util.Clamp<float>(ret.X, 0f, 1000000f);
+            ret.Y = Util.Clamp<float>(ret.Y, 0f, 1000000f);
+            DetailLog("{0},BSTerrainManager.ClampPositionToKnownTerrain,zeroingNegXorY,oldPos={1},newPos={2}",
+                                        BSScene.DetailLogZero, pPos, ret);
+        }
+
         // Can't do this function if we don't know about any terrain.
         if (m_terrains.Count == 0)
             return ret;
 
-        int loopPrevention = 5;
+        int loopPrevention = 10;
         Vector3 terrainBaseXYZ;
         BSTerrainPhys physTerrain;
         while (!GetTerrainPhysicalAtXYZ(ret, out physTerrain, out terrainBaseXYZ))
         {
             // The passed position is not within a known terrain area.
+            // NOTE that GetTerrainPhysicalAtXYZ will set 'terrainBaseXYZ' to the base of the unfound region.
 
-            // First, base addresses are never negative so correct for that possible problem.
-            if (ret.X < 0f || ret.Y < 0f)
-            {
-                if (ret.X < 0f)
-                    ret.X = 0f;
-                if (ret.Y < 0f)
-                    ret.Y = 0f;
-                DetailLog("{0},BSTerrainManager.ClampPositionToKnownTerrain,zeroingNegXorY,oldPos={1},newPos={2}",
-                                            BSScene.DetailLogZero, pPos, ret);
-            }
-            else
-            {
-                // Must be off the top of a region. Find an adjacent region to move into.
-                Vector3 adjacentTerrainBase = FindAdjacentTerrainBase(terrainBaseXYZ);
+            // Must be off the top of a region. Find an adjacent region to move into.
+            Vector3 adjacentTerrainBase = FindAdjacentTerrainBase(terrainBaseXYZ);
+
+            ret.X = Math.Min(ret.X, adjacentTerrainBase.X + (ret.X % DefaultRegionSize.X));
+            ret.Y = Math.Min(ret.Y, adjacentTerrainBase.Y + (ret.X % DefaultRegionSize.Y));
+            DetailLog("{0},BSTerrainManager.ClampPositionToKnownTerrain,findingAdjacentRegion,adjacentRegBase={1},oldPos={2},newPos={3}",
+                                        BSScene.DetailLogZero, adjacentTerrainBase, pPos, ret);
 
-                ret.X = Math.Min(ret.X, adjacentTerrainBase.X + DefaultRegionSize.X);
-                ret.Y = Math.Min(ret.Y, adjacentTerrainBase.Y + DefaultRegionSize.Y);
-                DetailLog("{0},BSTerrainManager.ClampPositionToKnownTerrain,findingAdjacentRegion,adjacentRegBase={1},oldPos={2},newPos={3}",
-                                            BSScene.DetailLogZero, adjacentTerrainBase, pPos, ret);
-            }
             if (loopPrevention-- < 0f)
             {
                 // The 'while' is a little dangerous so this prevents looping forever if the
@@ -383,6 +391,7 @@ public sealed class BSTerrainManager : IDisposable
                 break;
             }
         }
+
         return ret;
     }
 
@@ -479,11 +488,20 @@ public sealed class BSTerrainManager : IDisposable
     private Vector3 FindAdjacentTerrainBase(Vector3 pTerrainBase)
     {
         Vector3 ret = pTerrainBase;
+
+        // Can't do this function if we don't know about any terrain.
+        if (m_terrains.Count == 0)
+            return ret;
+
+        // Just some sanity
+        ret.X = Util.Clamp<float>(ret.X, 0f, 1000000f);
+        ret.Y = Util.Clamp<float>(ret.Y, 0f, 1000000f);
         ret.Z = 0f;
+
         lock (m_terrains)
         {
             // Once down to the <0,0> region, we have to be done.
-            while (ret.X > 0f && ret.Y > 0f)
+            while (ret.X > 0f || ret.Y > 0f)
             {
                 if (ret.X > 0f)
                 {
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
index a9cd8a1..2ce1513 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSTerrainMesh.cs
@@ -98,20 +98,20 @@ public sealed class BSTerrainMesh : BSTerrainPhys
         if (!meshCreationSuccess)
         {
             // DISASTER!!
-            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedConversionOfHeightmap", ID);
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedConversionOfHeightmap,id={1}", BSScene.DetailLogZero, 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;
         }
 
-        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,meshed,indices={1},indSz={2},vertices={3},vertSz={4}", 
-                                ID, indicesCount, indices.Length, verticesCount, vertices.Length);
+        PhysicsScene.DetailLog("{0},BSTerrainMesh.create,meshed,id={1},indices={2},indSz={3},vertices={4},vertSz={5}", 
+                                BSScene.DetailLogZero, ID, indicesCount, indices.Length, verticesCount, vertices.Length);
 
         m_terrainShape = PhysicsScene.PE.CreateMeshShape(PhysicsScene.World, indicesCount, indices, verticesCount, vertices);
         if (!m_terrainShape.HasPhysicalShape)
         {
             // DISASTER!!
-            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedCreationOfShape", ID);
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.create,failedCreationOfShape,id={1}", BSScene.DetailLogZero, 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;
@@ -151,7 +151,7 @@ public sealed class BSTerrainMesh : BSTerrainPhys
 
         if (BSParam.UseSingleSidedMeshes)
         {
-            PhysicsScene.DetailLog("{0},BSTerrainMesh.settingCustomMaterial", id);
+            PhysicsScene.DetailLog("{0},BSTerrainMesh.settingCustomMaterial,id={1}", BSScene.DetailLogZero, id);
             PhysicsScene.PE.AddToCollisionFlags(m_terrainBody, CollisionFlags.CF_CUSTOM_MATERIAL_CALLBACK);
         }