BulletSim: fix not moving physical objects below terrain to over terrain.

Add locking on register prestep action list preventing potential race conditions.
Little comment and formatting changes.

OpenSim/Region/Physics/BulletSPlugin/BSAPIUnman.cs

@@ -202,7 +202,7 @@ private void BulletLoggerPhysLog(string msg)
 }
 
 public override int PhysicsStep(BulletWorld world, float timeStep, int maxSubSteps, float fixedTimeStep,
-                        out int updatedEntityCount, out int collidersCount)
+                                        out int updatedEntityCount, out int collidersCount)
 {
     BulletWorldUnman worldu = world as BulletWorldUnman;
     return BSAPICPP.PhysicsStep2(worldu.ptr, timeStep, maxSubSteps, fixedTimeStep, out updatedEntityCount, out collidersCount);

OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs

@@ -126,9 +126,9 @@ public sealed class BSCharacter : BSPhysObject
         DetailLog("{0},BSCharacter.Destroy", LocalID);
         PhysicsScene.TaintedObject("BSCharacter.destroy", delegate()
         {
-            PhysicsScene.Shapes.DereferenceBody(PhysBody, true, null);
+            PhysicsScene.Shapes.DereferenceBody(PhysBody, true /* inTaintTime */, null /* bodyCallback */);
             PhysBody.Clear();
-            PhysicsScene.Shapes.DereferenceShape(PhysShape, true, null);
+            PhysicsScene.Shapes.DereferenceShape(PhysShape, true /* inTaintTime */, null /* bodyCallback */);
             PhysShape.Clear();
         });
     }

OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs

@@ -382,10 +382,13 @@ public abstract class BSPhysObject : PhysicsActor
     {
         string identifier = op + "-" + id.ToString();
 
-        // Clean out any existing action
+        lock (RegisteredActions)
-        UnRegisterPreStepAction(op, id);
+        {
+            // Clean out any existing action
+            UnRegisterPreStepAction(op, id);
 
-        RegisteredActions[identifier] = actn;
+            RegisteredActions[identifier] = actn;
+        }
         PhysicsScene.BeforeStep += actn;
         DetailLog("{0},BSPhysObject.RegisterPreStepAction,id={1}", LocalID, identifier);
     }
@@ -395,22 +398,28 @@ public abstract class BSPhysObject : PhysicsActor
     {
         string identifier = op + "-" + id.ToString();
         bool removed = false;
-        if (RegisteredActions.ContainsKey(identifier))
+        lock (RegisteredActions)
         {
-            PhysicsScene.BeforeStep -= RegisteredActions[identifier];
+            if (RegisteredActions.ContainsKey(identifier))
-            RegisteredActions.Remove(identifier);
+            {
-            removed = true;
+                PhysicsScene.BeforeStep -= RegisteredActions[identifier];
+                RegisteredActions.Remove(identifier);
+                removed = true;
+            }
         }
         DetailLog("{0},BSPhysObject.UnRegisterPreStepAction,id={1},removed={2}", LocalID, identifier, removed);
     }
 
     protected void UnRegisterAllPreStepActions()
     {
-        foreach (KeyValuePair<string, BSScene.PreStepAction> kvp in RegisteredActions)
+        lock (RegisteredActions)
         {
-            PhysicsScene.BeforeStep -= kvp.Value;
+            foreach (KeyValuePair<string, BSScene.PreStepAction> kvp in RegisteredActions)
+            {
+                PhysicsScene.BeforeStep -= kvp.Value;
+            }
+            RegisteredActions.Clear();
         }
-        RegisteredActions.Clear();
         DetailLog("{0},BSPhysObject.UnRegisterAllPreStepActions,", LocalID);
     }
 

OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs

@@ -379,7 +379,7 @@ public sealed class BSPrim : BSPhysObject
             // If the object is below ground it just has to be moved up because pushing will
             //     not get it through the terrain
             _position.Z = targetHeight;
-            if (!inTaintTime)
+            if (inTaintTime)
                 ForcePosition = _position;
             ret = true;
         }

OpenSim/Region/Physics/BulletSPlugin/BSScene.cs

@@ -387,12 +387,14 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
         if (!m_initialized) return null;
 
         BSCharacter actor = new BSCharacter(localID, avName, this, position, size, isFlying);
-        lock (PhysObjects) PhysObjects.Add(localID, actor);
+        lock (PhysObjects)
+            PhysObjects.Add(localID, actor);
 
         // TODO: Remove kludge someday.
         // We must generate a collision for avatars whether they collide or not.
         // This is required by OpenSim to update avatar animations, etc.
-        lock (m_avatars) m_avatars.Add(actor);
+        lock (m_avatars)
+            m_avatars.Add(actor);
 
         return actor;
     }
@@ -408,9 +410,11 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
         {
             try
             {
-                lock (PhysObjects) PhysObjects.Remove(actor.LocalID);
+                lock (PhysObjects)
+                    PhysObjects.Remove(bsactor.LocalID);
                 // Remove kludge someday
-                lock (m_avatars) m_avatars.Remove(bsactor);
+                lock (m_avatars)
+                    m_avatars.Remove(bsactor);
             }
             catch (Exception e)
             {
@@ -419,6 +423,11 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
             bsactor.Destroy();
             // bsactor.dispose();
         }
+        else
+        {
+            m_log.ErrorFormat("{0}: Requested to remove avatar that is not a BSCharacter. ID={1}, type={2}",
+                                        LogHeader, actor.LocalID, actor.GetType().Name);
+        }
     }
 
     public override void RemovePrim(PhysicsActor prim)