17 files changed, 292 insertions, 116 deletions

diff --git a/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs b/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
index a422552..b64d372 100644
--- a/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
+++ b/OpenSim/Region/CoreModules/Framework/EntityTransfer/EntityTransferModule.cs
@@ -36,6 +36,7 @@ using OpenSim.Framework.Capabilities;
 using OpenSim.Framework.Client;
 using OpenSim.Region.Framework.Interfaces;
 using OpenSim.Region.Framework.Scenes;
+using OpenSim.Region.Physics.Manager;
 using OpenSim.Services.Interfaces;
 
 using GridRegion = OpenSim.Services.Interfaces.GridRegion;
@@ -1761,9 +1762,10 @@ namespace OpenSim.Region.CoreModules.Framework.EntityTransfer
                 {
                     if (!grp.IsDeleted)
                     {
-                        if (grp.RootPart.PhysActor != null)
+                        PhysicsActor pa = grp.RootPart.PhysActor;
+                        if (pa != null)
                         {
-                            grp.RootPart.PhysActor.CrossingFailure();
+                            pa.CrossingFailure();
                             if (grp.RootPart.KeyframeMotion != null)
                             {
                                 grp.RootPart.Velocity = Vector3.Zero;
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/BMP.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/BMP.cs
index 90f124b..fb57c82 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/BMP.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/BMP.cs
@@ -72,5 +72,11 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "BMP";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public override bool SupportsTileSave()
+        {
+            return false;
+        }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GIF.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GIF.cs
index f331b56..79cc50b 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GIF.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GIF.cs
@@ -57,5 +57,11 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "GIF";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public override bool SupportsTileSave()
+        {
+            return false;
+        }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GenericSystemDrawing.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GenericSystemDrawing.cs
index 58925fd..da81dc1 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GenericSystemDrawing.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/GenericSystemDrawing.cs
@@ -177,6 +177,12 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
             return "SYS.DRAWING";
         }
 
+        //Returns true if this extension is supported for terrain save-tile
+        public virtual bool SupportsTileSave()
+        {
+            return false;
+        }
+
         /// <summary>
         /// Protected method, generates a grayscale bitmap
         /// image from a specified terrain channel.
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/JPEG.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/JPEG.cs
index 1a0d8ec..699d67a 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/JPEG.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/JPEG.cs
@@ -91,6 +91,12 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
             return "JPEG";
         }
 
+        //Returns true if this extension is supported for terrain save-tile
+        public bool SupportsTileSave()
+        {
+            return false;
+        }
+
         private static Bitmap CreateBitmapFromMap(ITerrainChannel map)
         {
             Bitmap gradientmapLd = new Bitmap("defaultstripe.png");
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/LLRAW.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/LLRAW.cs
index fad7641..62d232e 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/LLRAW.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/LLRAW.cs
@@ -254,5 +254,12 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "LL/SL RAW";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public bool SupportsTileSave()
+        {
+            return false;
+        }
+
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/PNG.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/PNG.cs
index e009ecf..c5c12ae 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/PNG.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/PNG.cs
@@ -57,5 +57,11 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "PNG";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public override bool SupportsTileSave()
+        {
+            return true;
+        }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/RAW32.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/RAW32.cs
index ba073ca..9fb7ef7 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/RAW32.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/RAW32.cs
@@ -173,5 +173,11 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "RAW32";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public bool SupportsTileSave()
+        {
+            return false;
+        }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/TIFF.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/TIFF.cs
index fc1ad33..5d2f893 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/TIFF.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/TIFF.cs
@@ -57,5 +57,11 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
         {
             return "TIFF";
         }
+
+        //Returns true if this extension is supported for terrain save-tile
+        public bool SupportsTileSave()
+        {
+            return false;
+        }
     }
 }
diff --git a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/Terragen.cs b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/Terragen.cs
index 2f37d9d..1ebf916 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/Terragen.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/FileLoaders/Terragen.cs
@@ -323,6 +323,12 @@ namespace OpenSim.Region.CoreModules.World.Terrain.FileLoaders
             return "Terragen";
         }
 
+        //Returns true if this extension is supported for terrain save-tile
+        public bool SupportsTileSave()
+        {
+            return false;
+        }
+
         /// <summary>
         /// terragen SCAL floats need to be written intel ordered regardless of
         /// big or little endian system
diff --git a/OpenSim/Region/CoreModules/World/Terrain/ITerrainLoader.cs b/OpenSim/Region/CoreModules/World/Terrain/ITerrainLoader.cs
index d407617..3ba3657 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/ITerrainLoader.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/ITerrainLoader.cs
@@ -32,6 +32,10 @@ namespace OpenSim.Region.CoreModules.World.Terrain
 {
     public interface ITerrainLoader
     {
+        // Returns true if that extension can be used for terrain save-tile
+        // (Look into each file in Region.CoreModules.World.Terrain.FileLoaders) 
+        bool SupportsTileSave();
+
         string FileExtension { get; }
         ITerrainChannel LoadFile(string filename);
         ITerrainChannel LoadFile(string filename, int fileStartX, int fileStartY, int fileWidth, int fileHeight, int sectionWidth, int sectionHeight);
diff --git a/OpenSim/Region/CoreModules/World/Terrain/TerrainModule.cs b/OpenSim/Region/CoreModules/World/Terrain/TerrainModule.cs
index 14e428e..e2bd769 100644
--- a/OpenSim/Region/CoreModules/World/Terrain/TerrainModule.cs
+++ b/OpenSim/Region/CoreModules/World/Terrain/TerrainModule.cs
@@ -93,6 +93,9 @@ namespace OpenSim.Region.CoreModules.World.Terrain
         /// </summary>
         private string m_supportedFileExtensions = "";
 
+        //For terrain save-tile file extensions
+        private string m_supportFileExtensionsForTileSave = "";
+
         #region ICommandableModule Members
 
         public ICommander CommandInterface
@@ -148,11 +151,20 @@ namespace OpenSim.Region.CoreModules.World.Terrain
 
             // Generate user-readable extensions list
             string supportedFilesSeparator = "";
+            string supportedFilesSeparatorForTileSave = "";
 
+            m_supportFileExtensionsForTileSave = "";
             foreach (KeyValuePair<string, ITerrainLoader> loader in m_loaders)
             {
                 m_supportedFileExtensions += supportedFilesSeparator + loader.Key + " (" + loader.Value + ")";
                 supportedFilesSeparator = ", ";
+
+                //For terrain save-tile file extensions
+                if (loader.Value.SupportsTileSave() == true)
+                {
+                    m_supportFileExtensionsForTileSave += supportedFilesSeparatorForTileSave + loader.Key + " (" + loader.Value + ")";
+                    supportedFilesSeparatorForTileSave = ", ";
+                }
             }
         }
 
@@ -589,7 +601,7 @@ namespace OpenSim.Region.CoreModules.World.Terrain
             // this region is included in the tile request
             foreach (KeyValuePair<string, ITerrainLoader> loader in m_loaders)
             {
-                if (filename.EndsWith(loader.Key))
+                if (filename.EndsWith(loader.Key) && loader.Value.SupportsTileSave())
                 {
                     lock (m_scene)
                     {
@@ -610,7 +622,7 @@ namespace OpenSim.Region.CoreModules.World.Terrain
 
             MainConsole.Instance.OutputFormat(
                 "ERROR: Could not save terrain from {0} to {1}.  Valid file extensions are {2}",
-                m_scene.RegionInfo.RegionName, filename, m_supportedFileExtensions);
+                m_scene.RegionInfo.RegionName, filename, m_supportFileExtensionsForTileSave);
         }
 
         /// <summary>
@@ -1194,7 +1206,7 @@ namespace OpenSim.Region.CoreModules.World.Terrain
                 new Command("save-tile", CommandIntentions.COMMAND_HAZARDOUS, InterfaceSaveTileFile, "Saves the current heightmap to the larger file.");
             saveToTileCommand.AddArgument("filename",
                                             "The file you wish to save to, the file extension determines the loader to be used. Supported extensions include: " +
-                                            m_supportedFileExtensions, "String");
+                                            m_supportFileExtensionsForTileSave, "String");
             saveToTileCommand.AddArgument("file width", "The width of the file in tiles", "Integer");
             saveToTileCommand.AddArgument("file height", "The height of the file in tiles", "Integer");
             saveToTileCommand.AddArgument("minimum X tile", "The X region coordinate of the first section on the file",
diff --git a/OpenSim/Region/Framework/Scenes/Scene.cs b/OpenSim/Region/Framework/Scenes/Scene.cs
index 539ca14..df37b98 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.cs
@@ -666,10 +666,6 @@ namespace OpenSim.Region.Framework.Scenes
 
             #endregion Region Settings
 
-            MainConsole.Instance.Commands.AddCommand("Estates", false, "reload estate",
-                                          "reload estate",
-                                          "Reload the estate data", HandleReloadEstate);
-
             //Bind Storage Manager functions to some land manager functions for this scene
             EventManager.OnLandObjectAdded +=
                 new EventManager.LandObjectAdded(simDataService.StoreLandObject);
diff --git a/OpenSim/Region/Framework/Scenes/SceneGraph.cs b/OpenSim/Region/Framework/Scenes/SceneGraph.cs
index 9fdbc54..cd4bd42 100644
--- a/OpenSim/Region/Framework/Scenes/SceneGraph.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneGraph.cs
@@ -348,7 +348,8 @@ namespace OpenSim.Region.Framework.Scenes
             if (rot != null)
                 sceneObject.UpdateGroupRotationR((Quaternion)rot);
 
-            if (sceneObject.RootPart.PhysActor != null && sceneObject.RootPart.PhysActor.IsPhysical && vel != Vector3.Zero)
+            PhysicsActor pa = sceneObject.RootPart.PhysActor;
+            if (pa != null && pa.IsPhysical && vel != Vector3.Zero)
             {
                 sceneObject.RootPart.ApplyImpulse((vel * sceneObject.GetMass()), false);
                 sceneObject.Velocity = vel;
diff --git a/OpenSim/Region/Framework/Scenes/SceneObjectGroup.cs b/OpenSim/Region/Framework/Scenes/SceneObjectGroup.cs
index 11fd721..5b47fc0 100644
--- a/OpenSim/Region/Framework/Scenes/SceneObjectGroup.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneObjectGroup.cs
@@ -725,16 +725,21 @@ namespace OpenSim.Region.Framework.Scenes
             {
                 m_isSelected = value;
                 // Tell physics engine that group is selected
-                if (m_rootPart.PhysActor != null)
+
+                PhysicsActor pa = m_rootPart.PhysActor;
+                if (pa != null)
                 {
-                    m_rootPart.PhysActor.Selected = value;
+                    pa.Selected = value;
+
                     // Pass it on to the children.
                     SceneObjectPart[] parts = m_parts.GetArray();
                     for (int i = 0; i < parts.Length; i++)
                     {
                         SceneObjectPart child = parts[i];
-                        if (child.PhysActor != null)
-                            child.PhysActor.Selected = value;
+
+                        PhysicsActor childPa = child.PhysActor;
+                        if (childPa != null)
+                            childPa.Selected = value;
                     }
                 }
                 if (RootPart.KeyframeMotion != null)
@@ -2166,29 +2171,58 @@ namespace OpenSim.Region.Framework.Scenes
             }
             else
             {
-                if (RootPart.PhysActor != null)
+                PhysicsActor pa = RootPart.PhysActor;
+
+                if (pa != null)
                 {
-                    RootPart.PhysActor.AddForce(impulse, true);
-                    m_scene.PhysicsScene.AddPhysicsActorTaint(RootPart.PhysActor);
+                    pa.AddForce(impulse, true);
+                    m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
                 }
             }
         }
 
         public void applyAngularImpulse(Vector3 impulse)
         {
-            if (RootPart.PhysActor != null)
+            PhysicsActor pa = RootPart.PhysActor;
+
+            if (pa != null)
             {
                 if (!IsAttachment)
                 {
-                    RootPart.PhysActor.AddAngularForce(impulse, true);
-                    m_scene.PhysicsScene.AddPhysicsActorTaint(RootPart.PhysActor);
+                    pa.AddAngularForce(impulse, true);
+                    m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
+                }
+            }
+        }
+
+        public void setAngularImpulse(Vector3 impulse)
+        {
+            PhysicsActor pa = RootPart.PhysActor;
+
+            if (pa != null)
+            {
+                if (!IsAttachment)
+                {
+                    pa.Torque = impulse;
+                    m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
                 }
             }
         }
 
         public Vector3 GetTorque()
         {
-            return RootPart.Torque;
+            PhysicsActor pa = RootPart.PhysActor;
+
+            if (pa != null)
+            {
+                if (!IsAttachment)
+                {
+                    Vector3 torque = pa.Torque;
+                    return torque;
+                }
+            }
+
+            return Vector3.Zero;
         }
 
          // This is used by both Double-Click Auto-Pilot and llMoveToTarget() in an attached object
@@ -2204,19 +2238,23 @@ namespace OpenSim.Region.Framework.Scenes
             }
             else
             {
-                if (RootPart.PhysActor != null)
+                PhysicsActor pa = RootPart.PhysActor;
+
+                if (pa != null)
                 {
-                    RootPart.PhysActor.PIDTarget = target;
-                    RootPart.PhysActor.PIDTau = tau;
-                    RootPart.PhysActor.PIDActive = true;
+                    pa.PIDTarget = target;
+                    pa.PIDTau = tau;
+                    pa.PIDActive = true;
                 }
             }
         }
 
         public void stopMoveToTarget()
         {
-            if (RootPart.PhysActor != null)
-                RootPart.PhysActor.PIDActive = false;
+            PhysicsActor pa = RootPart.PhysActor;
+
+            if (pa != null)
+                pa.PIDActive = false;
         }
         
         public void rotLookAt(Quaternion target, float strength, float damping)
@@ -2267,18 +2305,20 @@ namespace OpenSim.Region.Framework.Scenes
         /// <param name="tau">Number of seconds over which to reach target</param>
         public void SetHoverHeight(float height, PIDHoverType hoverType, float tau)
         {
-            if (RootPart.PhysActor != null)
+            PhysicsActor pa = RootPart.PhysActor;
+
+            if (pa != null)
             {
                 if (height != 0f)
                 {
-                    RootPart.PhysActor.PIDHoverHeight = height;
-                    RootPart.PhysActor.PIDHoverType = hoverType;
-                    RootPart.PhysActor.PIDTau = tau;
-                    RootPart.PhysActor.PIDHoverActive = true;
+                    pa.PIDHoverHeight = height;
+                    pa.PIDHoverType = hoverType;
+                    pa.PIDTau = tau;
+                    pa.PIDHoverActive = true;
                 }
                 else
                 {
-                    RootPart.PhysActor.PIDHoverActive = false;
+                    pa.PIDHoverActive = false;
                 }
             }
         }
@@ -2771,10 +2811,10 @@ namespace OpenSim.Region.Framework.Scenes
             linkPart.ParentID = 0;
             linkPart.LinkNum = 0;
 
-            if (linkPart.PhysActor != null)
-            {
-                m_scene.PhysicsScene.RemovePrim(linkPart.PhysActor);
-            }
+            PhysicsActor linkPartPa = linkPart.PhysActor;
+
+            if (linkPartPa != null)
+                m_scene.PhysicsScene.RemovePrim(linkPartPa);
 
             // We need to reset the child part's position
             // ready for life as a separate object after being a part of another object
@@ -2875,17 +2915,19 @@ namespace OpenSim.Region.Framework.Scenes
         {
             if (m_scene.EventManager.TriggerGroupMove(UUID, pos))
             {
-                if (m_rootPart.PhysActor != null)
+                PhysicsActor pa = m_rootPart.PhysActor;
+
+                if (pa != null)
                 {
-                    if (m_rootPart.PhysActor.IsPhysical)
+                    if (pa.IsPhysical)
                     {
                         if (!m_rootPart.BlockGrab)
                         {
                             Vector3 llmoveforce = pos - AbsolutePosition;
                             Vector3 grabforce = llmoveforce;
-                            grabforce = (grabforce / 10) * m_rootPart.PhysActor.Mass;
-                            m_rootPart.PhysActor.AddForce(grabforce, true);
-                            m_scene.PhysicsScene.AddPhysicsActorTaint(m_rootPart.PhysActor);
+                            grabforce = (grabforce / 10) * pa.Mass;
+                            pa.AddForce(grabforce, true);
+                            m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
                         }
                     }
                     else
@@ -2915,9 +2957,11 @@ namespace OpenSim.Region.Framework.Scenes
         {
             if (m_scene.EventManager.TriggerGroupSpinStart(UUID))
             {
-                if (m_rootPart.PhysActor != null)
+                PhysicsActor pa = m_rootPart.PhysActor;
+
+                if (pa != null)
                 {
-                    if (m_rootPart.PhysActor.IsPhysical)
+                    if (pa.IsPhysical)
                     {
                         m_rootPart.IsWaitingForFirstSpinUpdatePacket = true;
                     }
@@ -2958,12 +3002,13 @@ namespace OpenSim.Region.Framework.Scenes
             // but it will result in over-shoot or under-shoot of the target orientation.
             // For the end user, this means that ctrl+shift+drag can be used for relative,
             // but not absolute, adjustments of orientation for physical prims.
-          
             if (m_scene.EventManager.TriggerGroupSpin(UUID, newOrientation))
             {
-                if (m_rootPart.PhysActor != null)
+                PhysicsActor pa = m_rootPart.PhysActor;
+
+                if (pa != null)
                 {
-                    if (m_rootPart.PhysActor.IsPhysical)
+                    if (pa.IsPhysical)
                     {
                         if (m_rootPart.IsWaitingForFirstSpinUpdatePacket)
                         {
@@ -2989,9 +3034,9 @@ namespace OpenSim.Region.Framework.Scenes
 
                           //m_log.Error("SCENE OBJECT GROUP]: rotation axis is " + rotationAxis);
                           Vector3 spinforce = new Vector3(rotationAxis.X, rotationAxis.Y, rotationAxis.Z);
-                          spinforce = (spinforce/8) * m_rootPart.PhysActor.Mass; // 8 is an arbitrary torque scaling factor
-                          m_rootPart.PhysActor.AddAngularForce(spinforce,true);
-                          m_scene.PhysicsScene.AddPhysicsActorTaint(m_rootPart.PhysActor);
+                          spinforce = (spinforce/8) * pa.Mass; // 8 is an arbitrary torque scaling factor
+                          pa.AddAngularForce(spinforce,true);
+                          m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
                         }
                     }
                     else
@@ -3199,8 +3244,10 @@ namespace OpenSim.Region.Framework.Scenes
             {
                 part.UpdateShape(shapeBlock);
 
-                if (part.PhysActor != null)
-                    m_scene.PhysicsScene.AddPhysicsActorTaint(part.PhysActor);
+                PhysicsActor pa = m_rootPart.PhysActor;
+
+                if (pa != null)
+                    m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
             }
         }
 
@@ -3218,7 +3265,9 @@ namespace OpenSim.Region.Framework.Scenes
             scale.Y = Math.Min(scale.Y, Scene.m_maxNonphys);
             scale.Z = Math.Min(scale.Z, Scene.m_maxNonphys);
 
-            if (RootPart.PhysActor != null && RootPart.PhysActor.IsPhysical)
+            PhysicsActor pa = m_rootPart.PhysActor;
+
+            if (pa != null && pa.IsPhysical)
             {
                 scale.X = Math.Min(scale.X, Scene.m_maxPhys);
                 scale.Y = Math.Min(scale.Y, Scene.m_maxPhys);
@@ -3243,7 +3292,7 @@ namespace OpenSim.Region.Framework.Scenes
                         float f = 1.0f;
                         float a = 1.0f;
 
-                        if (RootPart.PhysActor != null && RootPart.PhysActor.IsPhysical)
+                        if (pa != null && pa.IsPhysical)
                         {
                             if (oldSize.X * x > m_scene.m_maxPhys)
                             {
@@ -3558,13 +3607,17 @@ namespace OpenSim.Region.Framework.Scenes
             // needs to be called with phys building true
             Quaternion axRot = rot;
             Quaternion oldParentRot = m_rootPart.RotationOffset;
-            
+
+            m_rootPart.StoreUndoState();
             //Don't use UpdateRotation because it schedules an update prematurely
             m_rootPart.RotationOffset = rot;
-            if (m_rootPart.PhysActor != null)
+
+            PhysicsActor pa = m_rootPart.PhysActor;
+
+            if (pa != null)
             {
-                m_rootPart.PhysActor.Orientation = m_rootPart.RotationOffset;
-                m_scene.PhysicsScene.AddPhysicsActorTaint(m_rootPart.PhysActor);
+                pa.Orientation = m_rootPart.RotationOffset;
+                m_scene.PhysicsScene.AddPhysicsActorTaint(pa);
             }
 
             SceneObjectPart[] parts = m_parts.GetArray();
diff --git a/OpenSim/Region/Framework/Scenes/SceneObjectPart.cs b/OpenSim/Region/Framework/Scenes/SceneObjectPart.cs
index cfa3cd4..83b0b18 100644
--- a/OpenSim/Region/Framework/Scenes/SceneObjectPart.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneObjectPart.cs
@@ -152,6 +152,14 @@ namespace OpenSim.Region.Framework.Scenes
         public int[] PayPrice = {-2,-2,-2,-2,-2};
 
         [XmlIgnore]
+        /// <summary>
+        /// The representation of this part in the physics scene.
+        /// </summary>
+        /// <remarks>
+        /// If you use this property more than once in a section of code then you must take a reference and use that.
+        /// If another thread is simultaneously turning physics off on this part then this refernece could become
+        /// null at any time.
+        /// </remarks>
         public PhysicsActor PhysActor
         {
             get { return m_physActor; }
@@ -555,10 +563,25 @@ namespace OpenSim.Region.Framework.Scenes
             set 
             { 
                 m_name = value;
-                if (PhysActor != null)
-                {
-                    PhysActor.SOPName = value;
-                }
+
+                PhysicsActor pa = PhysActor;
+
+                if (pa != null)
+                    pa.SOPName = value;
+            }
+        }
+
+        public byte Material
+        {
+            get { return (byte) m_material; }
+            set
+            {
+                m_material = (Material)value;
+
+                PhysicsActor pa = PhysActor;
+
+                if (pa != null)
+                    pa.SetMaterial((int)value);
             }
         }
 
@@ -1017,7 +1040,7 @@ namespace OpenSim.Region.Framework.Scenes
                                 if (Shape.SculptEntry)
                                     CheckSculptAndLoad();
                                 else
-                                    ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(PhysActor);
+                                    ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(actor);
                             }
                         }
                     }
@@ -1868,33 +1891,35 @@ namespace OpenSim.Region.Framework.Scenes
                     }
 
                     // Basic Physics can also return null as well as an exception catch.
-                    if (PhysActor != null)
+                    PhysicsActor pa = PhysActor;
+
+                    if (pa != null)
                     {
-                        PhysActor.SOPName = this.Name; // save object into the PhysActor so ODE internals know the joint/body info
-                        PhysActor.SetMaterial(Material);
+                        pa.SOPName = this.Name; // save object into the PhysActor so ODE internals know the joint/body info
+                        pa.SetMaterial(Material);
 
                         // if root part apply vehicle
                         if (m_vehicle != null && LocalId == ParentGroup.RootPart.LocalId)
-                            m_vehicle.SetVehicle(PhysActor);
+                            m_vehicle.SetVehicle(pa);
 
                         DoPhysicsPropertyUpdate(isPhysical, true);
                         if(VolumeDetectActive) // change if not the default only
-                            PhysActor.SetVolumeDetect(1);
+                            pa.SetVolumeDetect(1);
                      
                         if (!building)
-                            PhysActor.Building = false;
+                            pa.Building = false;
 
                         Velocity = velocity;
                         AngularVelocity = rotationalVelocity;
-                        PhysActor.Velocity = velocity;
-                        PhysActor.RotationalVelocity = rotationalVelocity;
+                        pa.Velocity = velocity;
+                        pa.RotationalVelocity = rotationalVelocity;
 
                         // if not vehicle and root part apply force and torque
                         if ((m_vehicle == null || m_vehicle.Type == Vehicle.TYPE_NONE)
                                 && LocalId == ParentGroup.RootPart.LocalId)
                         {
-                            PhysActor.Force = Force;
-                            PhysActor.Torque = Torque;
+                            pa.Force = Force;
+                            pa.Torque = Torque;
                         }
                     }
                 }
@@ -2125,11 +2150,13 @@ namespace OpenSim.Region.Framework.Scenes
             }
             else
             {
-                if (PhysActor != null)
+                PhysicsActor pa = PhysActor;
+
+                if (pa != null)
                 {
-                    if (UsePhysics != PhysActor.IsPhysical || isNew)
+                    if (UsePhysics != pa.IsPhysical || isNew)
                     {
-                        if (PhysActor.IsPhysical)
+                        if (pa.IsPhysical) // implies UsePhysics==false for this block
                         {
                             if (!isNew)  // implies UsePhysics==false for this block
                             {
@@ -2173,9 +2200,18 @@ namespace OpenSim.Region.Framework.Scenes
 
                             if (ParentID != 0 && ParentID != LocalId)
                             {
-                                if (ParentGroup.RootPart.PhysActor != null)
+                                ParentGroup.Scene.AddPhysicalPrim(1);
+
+                                pa.OnRequestTerseUpdate += PhysicsRequestingTerseUpdate;
+                                pa.OnOutOfBounds += PhysicsOutOfBounds;
+                                if (ParentID != 0 && ParentID != LocalId)
                                 {
-                                    PhysActor.link(ParentGroup.RootPart.PhysActor);
+                                    PhysicsActor parentPa = ParentGroup.RootPart.PhysActor;
+
+                                    if (parentPa != null)
+                                    {
+                                        pa.link(parentPa);
+                                    }
                                 }
                             }
                         }                           
@@ -2191,7 +2227,7 @@ namespace OpenSim.Region.Framework.Scenes
                     if (Shape.SculptEntry)
                         CheckSculptAndLoad();
                     else
-                        ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(PhysActor);
+                        ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(pa);
                 }
             }
         }
@@ -2302,23 +2338,27 @@ namespace OpenSim.Region.Framework.Scenes
 
         public Vector3 GetGeometricCenter()
         {
-            if (PhysActor != null)
-                return new Vector3(PhysActor.CenterOfMass.X, PhysActor.CenterOfMass.Y, PhysActor.CenterOfMass.Z);
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null)
+                return new Vector3(pa.CenterOfMass.X, pa.CenterOfMass.Y, pa.CenterOfMass.Z);
             else
                 return new Vector3(0, 0, 0);
         }
 
         public float GetMass()
         {
-            if (PhysActor != null)
-                return PhysActor.Mass;
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null)
+                return pa.Mass;
             else
                 return 0;
         }
 
         public Vector3 GetForce()
         {
-                return Force;
+            return Force;
         }
 
         /// <summary>
@@ -2947,9 +2987,11 @@ namespace OpenSim.Region.Framework.Scenes
 
         public void PhysicsRequestingTerseUpdate()
         {
-            if (PhysActor != null)
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null)
             {
-                Vector3 newpos = new Vector3(PhysActor.Position.GetBytes(), 0);
+                Vector3 newpos = new Vector3(pa.Position.GetBytes(), 0);
                 
                 if (ParentGroup.Scene.TestBorderCross(newpos, Cardinals.N)
                     || ParentGroup.Scene.TestBorderCross(newpos, Cardinals.S)
@@ -2961,6 +3003,7 @@ namespace OpenSim.Region.Framework.Scenes
                 }
                 //ParentGroup.RootPart.m_groupPosition = newpos;
             }
+
             ScheduleTerseUpdate();
         }
 
@@ -3052,7 +3095,9 @@ namespace OpenSim.Region.Framework.Scenes
             scale.Y = Math.Min(scale.Y, ParentGroup.Scene.m_maxNonphys);
             scale.Z = Math.Min(scale.Z, ParentGroup.Scene.m_maxNonphys);
 
-            if (PhysActor != null && PhysActor.IsPhysical)
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null && pa.IsPhysical)
             {
                 scale.X = Math.Min(scale.X, ParentGroup.Scene.m_maxPhys);
                 scale.Y = Math.Min(scale.Y, ParentGroup.Scene.m_maxPhys);
@@ -3214,12 +3259,14 @@ namespace OpenSim.Region.Framework.Scenes
                         m_shape.SculptData = texture.Data;
                     }
 
-                    if (PhysActor != null)
+                    PhysicsActor pa = PhysActor;
+
+                    if (pa != null)
                     {
                         // Update the physics actor with the new loaded sculpt data and set the taint signal.
-                        PhysActor.Shape = m_shape;
+                        pa.Shape = m_shape;
 
-                        ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(PhysActor);
+                        ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(pa);
                     }
                 }
             }
@@ -3495,17 +3542,10 @@ namespace OpenSim.Region.Framework.Scenes
 
         public void SetFloatOnWater(int floatYN)
         {
-            if (PhysActor != null)
-            {
-                if (floatYN == 1)
-                {
-                    PhysActor.FloatOnWater = true;
-                }
-                else
-                {
-                    PhysActor.FloatOnWater = false;
-                }
-            }
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null)
+                pa.FloatOnWater = floatYN == 1;
         }
 
         public void SetForce(Vector3 force)
@@ -4800,7 +4840,7 @@ namespace OpenSim.Region.Framework.Scenes
                 // Defensive programming calls for a check here.
                 // Better would be throwing an exception that could be catched by a unit test as the internal 
                 // logic should make sure, this Physactor is always here.
-                if (this.PhysActor != null)
+                if (pa != null)
                 {
                     PhysActor.SetVolumeDetect(1);
 //                    AddFlag(PrimFlags.Phantom); // We set this flag also if VD is active
@@ -4814,7 +4854,6 @@ namespace OpenSim.Region.Framework.Scenes
                 if (this.PhysActor != null)
                 {
                     PhysActor.SetVolumeDetect(0);
-                }
 
                 this.VolumeDetectActive = false;
             }
@@ -4827,6 +4866,7 @@ namespace OpenSim.Region.Framework.Scenes
             {
                 RemFlag(PrimFlags.TemporaryOnRez);
             }
+
             //            m_log.Debug("Update:  PHY:" + UsePhysics.ToString() + ", T:" + IsTemporary.ToString() + ", PHA:" + IsPhantom.ToString() + " S:" + CastsShadows.ToString());
 
            // and last in case we have a new actor and not building
@@ -4898,10 +4938,12 @@ namespace OpenSim.Region.Framework.Scenes
             m_shape.PathTwist = shapeBlock.PathTwist;
             m_shape.PathTwistBegin = shapeBlock.PathTwistBegin;
 
-            if (PhysActor != null)
+            PhysicsActor pa = PhysActor;
+
+            if (pa != null)
             {
-                PhysActor.Shape = m_shape;
-                ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(PhysActor);
+                pa.Shape = m_shape;
+                ParentGroup.Scene.PhysicsScene.AddPhysicsActorTaint(pa);
             }
 
             // This is what makes vehicle trailers work
@@ -5043,6 +5085,8 @@ namespace OpenSim.Region.Framework.Scenes
                 objectflagupdate |= (uint) PrimFlags.AllowInventoryDrop;
             }
 
+            PhysicsActor pa = PhysActor;
+
             if (
                 ((AggregateScriptEvents & scriptEvents.collision) != 0) ||
                 ((AggregateScriptEvents & scriptEvents.collision_end) != 0) ||
@@ -5054,18 +5098,18 @@ namespace OpenSim.Region.Framework.Scenes
                 )
             {
                 // subscribe to physics updates.
-                if (PhysActor != null)
+                if (pa != null)
                 {
-                    PhysActor.OnCollisionUpdate += PhysicsCollision;
-                    PhysActor.SubscribeEvents(1000);
+                    pa.OnCollisionUpdate += PhysicsCollision;
+                    pa.SubscribeEvents(1000);
                 }
             }
             else
             {
-                if (PhysActor != null)
+                if (pa != null)
                 {
-                    PhysActor.UnSubscribeEvents();
-                    PhysActor.OnCollisionUpdate -= PhysicsCollision;
+                    pa.UnSubscribeEvents();
+                    pa.OnCollisionUpdate -= PhysicsCollision;
                 }
             }
 
diff --git a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
index ce05b8c..5268ade 100644
--- a/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
+++ b/OpenSim/Region/ScriptEngine/Shared/Api/Implementation/LSL_Api.cs
@@ -1474,7 +1474,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
             if (scale.z < 0.01)
                 scale.z = 0.01;
 
-            if (part.ParentGroup.RootPart.PhysActor != null && part.ParentGroup.RootPart.PhysActor.IsPhysical)
+            PhysicsActor pa = part.ParentGroup.RootPart.PhysActor;
+
+            if (pa != null && pa.IsPhysical)
             {
                 if (scale.x > World.m_maxPhys)
                     scale.x = World.m_maxPhys;
@@ -2345,7 +2347,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
             // but only if the object is not physial and active.   This is important for rotating doors.
             // without the absoluteposition = absoluteposition happening, the doors do not move in the physics
             // scene
-            if (part.PhysActor != null && !part.PhysActor.IsPhysical)
+            PhysicsActor pa = part.PhysActor;
+
+            if (pa != null && !pa.IsPhysical)
             {
                 part.ParentGroup.ResetChildPrimPhysicsPositions();
             }
@@ -3073,7 +3077,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
 
                         float groupmass = new_group.GetMass();
 
-                        if (new_group.RootPart.PhysActor != null && new_group.RootPart.PhysActor.IsPhysical && llvel != Vector3.Zero)
+                        PhysicsActor pa = new_group.RootPart.PhysActor;
+
+                        if (pa != null && pa.IsPhysical && llvel != Vector3.Zero)
                         {
                             //Recoil.
                             llApplyImpulse(new LSL_Vector(llvel.X * groupmass, llvel.Y * groupmass, llvel.Z * groupmass), 0);
@@ -3510,6 +3516,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
         public void llSetHoverHeight(double height, int water, double tau)
         {
             m_host.AddScriptLPS(1);
+
             if (m_host.PhysActor != null)
             {
                 PIDHoverType hoverType = PIDHoverType.Ground;
@@ -3560,7 +3567,9 @@ namespace OpenSim.Region.ScriptEngine.Shared.Api
             
             // Per discussion with Melanie, for non-physical objects llLookAt appears to simply
             // set the rotation of the object, copy that behavior
-            if (strength == 0 || m_host.PhysActor == null || !m_host.PhysActor.IsPhysical)
+            PhysicsActor pa = m_host.PhysActor;
+
+            if (strength == 0 || pa == null || !pa.IsPhysical)
             {
                 llSetLocalRot(target);
             }