BulletSim: do not zero an avatar's standing velocity if it is standing

on a moving object.
Rearrange pre/post action subscription code to put more in locks.
Add meshmerizer params to BulletSimTestUtil scene creation (and fix line endings).
Rebuilt version of DLLs and SOs with cleaned up code and no profiling for sure.

OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs

@@ -96,6 +96,7 @@ public abstract class BSPhysObject : PhysicsActor
         CollidingStep = 0;
         CollidingGroundStep = 0;
         CollisionAccumulation = 0;
+        ColliderIsMoving = false;
         CollisionScore = 0;
     }
 
@@ -177,13 +178,14 @@ public abstract class BSPhysObject : PhysicsActor
     public abstract OMV.Vector3 RawPosition { get; set; }
     public abstract OMV.Vector3 ForcePosition { get; set; }
 
-    // Position is what the simulator thinks the positions of the prim is.
+    // 'Position' and 'Orientation' is what the simulator thinks the positions of the prim is.
     // Because Bullet needs the zero coordinate to be the center of mass of the linkset,
     //     sometimes it is necessary to displace the position the physics engine thinks
     //     the position is. PositionDisplacement must be added and removed from the
     //     position as the simulator position is stored and fetched from the physics
-    //     engine. 
+    //     engine. Similar to OrientationDisplacement.
     public virtual OMV.Vector3 PositionDisplacement { get; set; }
+    public virtual OMV.Quaternion OrientationDisplacement { get; set; }
 
     public abstract OMV.Quaternion RawOrientation { get; set; }
     public abstract OMV.Quaternion ForceOrientation { get; set; }
@@ -240,6 +242,9 @@ public abstract class BSPhysObject : PhysicsActor
     protected long CollidingObjectStep { get; set; }
     // The collision flags we think are set in Bullet
     protected CollisionFlags CurrentCollisionFlags { get; set; }
+    // On a collision, check the collider and remember if the last collider was moving
+    //    Used to modify the standing of avatars (avatars on stationary things stand still)
+    protected bool ColliderIsMoving;
 
     // Count of collisions for this object
     protected long CollisionAccumulation { get; set; }
@@ -307,7 +312,10 @@ public abstract class BSPhysObject : PhysicsActor
 
         CollisionAccumulation++;
 
-        // if someone has subscribed for collision events....
+        // For movement tests, remember if we are colliding with an object that is moving.
+        ColliderIsMoving = collidee != null ? collidee.RawVelocity != OMV.Vector3.Zero : false;
+
+        // If someone has subscribed for collision events log the collision so it will be reported up
         if (SubscribedEvents()) {
             CollisionCollection.AddCollider(collidingWith, new ContactPoint(contactPoint, contactNormal, pentrationDepth));
             DetailLog("{0},{1}.Collison.AddCollider,call,with={2},point={3},normal={4},depth={5}",
@@ -393,12 +401,13 @@ public abstract class BSPhysObject : PhysicsActor
     public override bool SubscribedEvents() {
         return (SubscribedEventsMs > 0);
     }
-    // Because 'CollisionScore' is calls many times while sorting it should not be recomputed
+    // Because 'CollisionScore' is called many times while sorting, it should not be recomputed
     //    each time called. So this is built to be light weight for each collision and to do
     //    all the processing when the user asks for the info.
     public void ComputeCollisionScore()
     {
-        // Scale the collision count by the time since the last collision
+        // Scale the collision count by the time since the last collision.
+        // The "+1" prevents dividing by zero.
         long timeAgo = PhysicsScene.SimulationStep - CollidingStep + 1;
         CollisionScore = CollisionAccumulation / timeAgo;
     }
@@ -423,13 +432,15 @@ public abstract class BSPhysObject : PhysicsActor
             UnRegisterPreStepAction(op, id);
 
             RegisteredPrestepActions[identifier] = actn;
+
+            PhysicsScene.BeforeStep += actn;
         }
-        PhysicsScene.BeforeStep += actn;
         DetailLog("{0},BSPhysObject.RegisterPreStepAction,id={1}", LocalID, identifier);
     }
 
     // Unregister a pre step action. Safe to call if the action has not been registered.
-    protected void UnRegisterPreStepAction(string op, uint id)
+    // Returns 'true' if an action was actually removed
+    protected bool UnRegisterPreStepAction(string op, uint id)
     {
         string identifier = op + "-" + id.ToString();
         bool removed = false;
@@ -443,6 +454,7 @@ public abstract class BSPhysObject : PhysicsActor
             }
         }
         DetailLog("{0},BSPhysObject.UnRegisterPreStepAction,id={1},removed={2}", LocalID, identifier, removed);
+        return removed;
     }
 
     protected void UnRegisterAllPreStepActions()
@@ -468,13 +480,15 @@ public abstract class BSPhysObject : PhysicsActor
             UnRegisterPostStepAction(op, id);
 
             RegisteredPoststepActions[identifier] = actn;
+
+            PhysicsScene.AfterStep += actn;
         }
-        PhysicsScene.AfterStep += actn;
         DetailLog("{0},BSPhysObject.RegisterPostStepAction,id={1}", LocalID, identifier);
     }
 
     // Unregister a pre step action. Safe to call if the action has not been registered.
-    protected void UnRegisterPostStepAction(string op, uint id)
+    // Returns 'true' if an action was actually removed.
+    protected bool UnRegisterPostStepAction(string op, uint id)
     {
         string identifier = op + "-" + id.ToString();
         bool removed = false;
@@ -488,6 +502,7 @@ public abstract class BSPhysObject : PhysicsActor
             }
         }
         DetailLog("{0},BSPhysObject.UnRegisterPostStepAction,id={1},removed={2}", LocalID, identifier, removed);
+        return removed;
     }
 
     protected void UnRegisterAllPostStepActions()