1 files changed, 146 insertions, 139 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
index 2b3fa25..68a0db6 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs
@@ -45,7 +45,6 @@ public sealed class BSPrim : BSPhysObject
     private static readonly string LogHeader = "[BULLETS PRIM]";
 
     // _size is what the user passed. Scale is what we pass to the physics engine with the mesh.
-    // Often Scale is unity because the meshmerizer will apply _size when creating the mesh.
     private OMV.Vector3 _size;  // the multiplier for each mesh dimension as passed by the user
 
     private bool _grabbed;
@@ -93,7 +92,7 @@ public sealed class BSPrim : BSPhysObject
         _physicsActorType = (int)ActorTypes.Prim;
         _position = pos;
         _size = size;
-        Scale = size;   // the scale will be set by CreateGeom depending on object type
+        Scale = size;   // prims are the size the user wants them to be (different for BSCharactes).
         _orientation = rotation;
         _buoyancy = 1f;
         _velocity = OMV.Vector3.Zero;
@@ -101,15 +100,20 @@ public sealed class BSPrim : BSPhysObject
         BaseShape = pbs;
         _isPhysical = pisPhysical;
         _isVolumeDetect = false;
-        _friction = PhysicsScene.Params.defaultFriction;  // TODO: compute based on object material
-        _density = PhysicsScene.Params.defaultDensity;    // TODO: compute based on object material
+
+        // Someday set default attributes based on the material but, for now, we don't know the prim material yet.
+        // MaterialAttributes primMat = BSMaterials.GetAttributes(Material, pisPhysical);
+        _density = PhysicsScene.Params.defaultDensity;
+        _friction = PhysicsScene.Params.defaultFriction;
         _restitution = PhysicsScene.Params.defaultRestitution;
+
         _vehicle = new BSDynamics(PhysicsScene, this);            // add vehicleness
+
         _mass = CalculateMass();
 
         // No body or shape yet
-        PhysBody = new BulletBody(LocalID, IntPtr.Zero);
-        PhysShape = new BulletShape(IntPtr.Zero);
+        PhysBody = new BulletBody(LocalID);
+        PhysShape = new BulletShape();
 
         DetailLog("{0},BSPrim.constructor,call", LocalID);
         // do the actual object creation at taint time
@@ -143,7 +147,9 @@ public sealed class BSPrim : BSPhysObject
             DetailLog("{0},BSPrim.Destroy,taint,", LocalID);
             // If there are physical body and shape, release my use of same.
             PhysicsScene.Shapes.DereferenceBody(PhysBody, true, null);
+            PhysBody.Clear();
             PhysicsScene.Shapes.DereferenceShape(PhysShape, true, null);
+            PhysShape.Clear();
         });
     }
 
@@ -157,12 +163,10 @@ public sealed class BSPrim : BSPhysObject
             // We presume the scale and size are the same. If scale must be changed for
             //     the physical shape, that is done when the geometry is built.
             _size = value;
+            Scale = _size;
             ForceBodyShapeRebuild(false);
         }
     }
-    // Scale is what we set in the physics engine. It is different than 'size' in that
-    //     'size' can be encorporated into the mesh. In that case, the scale is <1,1,1>.
-    public override OMV.Vector3 Scale { get; set; }
 
     public override PrimitiveBaseShape Shape {
         set {
@@ -189,13 +193,17 @@ public sealed class BSPrim : BSPhysObject
         }
     }
     public override bool Selected {
-        set {
-            _isSelected = value;
-            PhysicsScene.TaintedObject("BSPrim.setSelected", delegate()
+        set
+        {
+            if (value != _isSelected)
             {
-                DetailLog("{0},BSPrim.selected,taint,selected={1}", LocalID, _isSelected);
-                SetObjectDynamic(false);
-            });
+                _isSelected = value;
+                PhysicsScene.TaintedObject("BSPrim.setSelected", delegate()
+                {
+                    DetailLog("{0},BSPrim.selected,taint,selected={1}", LocalID, _isSelected);
+                    SetObjectDynamic(false);
+                });
+            }
         }
     }
     public override void CrossingFailure() { return; }
@@ -244,7 +252,8 @@ public sealed class BSPrim : BSPhysObject
         // Zero some other properties in the physics engine
         PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ZeroMotion", delegate()
         {
-            BulletSimAPI.ClearAllForces2(PhysBody.ptr);
+            if (PhysBody.HasPhysicalBody)
+                BulletSimAPI.ClearAllForces2(PhysBody.ptr);
         });
     }
     public override void ZeroAngularMotion(bool inTaintTime)
@@ -253,8 +262,12 @@ public sealed class BSPrim : BSPhysObject
         // Zero some other properties in the physics engine
         PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ZeroMotion", delegate()
         {
-            BulletSimAPI.SetInterpolationAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
-            BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, OMV.Vector3.Zero);
+            // DetailLog("{0},BSPrim.ZeroAngularMotion,call,rotVel={1}", LocalID, _rotationalVelocity);
+            if (PhysBody.HasPhysicalBody)
+            {
+                BulletSimAPI.SetInterpolationAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
+                BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
+            }
         });
     }
 
@@ -271,9 +284,12 @@ public sealed class BSPrim : BSPhysObject
     }
     public override OMV.Vector3 Position {
         get {
+            /* NOTE: this refetch is not necessary. The simulator knows about linkset children
+             *    and does not fetch this position info for children. Thus this is commented out.
             // child prims move around based on their parent. Need to get the latest location
             if (!Linkset.IsRoot(this))
-                _position = Linkset.Position(this);
+                _position = Linkset.PositionGet(this);
+            */
 
             // don't do the GetObjectPosition for root elements because this function is called a zillion times.
             // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
@@ -281,18 +297,22 @@ public sealed class BSPrim : BSPhysObject
         }
         set {
             // If the position must be forced into the physics engine, use ForcePosition.
+            // All positions are given in world positions.
             if (_position == value)
             {
+                DetailLog("{0},BSPrim.setPosition,taint,positionNotChanging,pos={1},orient={2}", LocalID, _position, _orientation);
                 return;
             }
             _position = value;
-            // TODO: what does it mean to set the position of a child prim?? Rebuild the constraint?
             PositionSanityCheck(false);
+
+            // A linkset might need to know if a component information changed.
+            Linkset.UpdateProperties(this, false);
+
             PhysicsScene.TaintedObject("BSPrim.setPosition", delegate()
             {
-                // DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
-                ActivateIfPhysical(false);
+                DetailLog("{0},BSPrim.SetPosition,taint,pos={1},orient={2}", LocalID, _position, _orientation);
+                ForcePosition = _position;
             });
         }
     }
@@ -303,9 +323,11 @@ public sealed class BSPrim : BSPhysObject
         }
         set {
             _position = value;
-            // PositionSanityCheck();   // Don't do this! Causes a loop and caller should know better.
-            BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
-            ActivateIfPhysical(false);
+            if (PhysBody.HasPhysicalBody)
+            {
+                BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+                ActivateIfPhysical(false);
+            }
         }
     }
 
@@ -316,39 +338,46 @@ public sealed class BSPrim : BSPhysObject
     {
         bool ret = false;
 
+        if (!PhysicsScene.TerrainManager.IsWithinKnownTerrain(_position))
+        {
+            // The physical object is out of the known/simulated area.
+            // Upper levels of code will handle the transition to other areas so, for
+            //     the time, we just ignore the position.
+            return ret;
+        }
+
         float terrainHeight = PhysicsScene.TerrainManager.GetTerrainHeightAtXYZ(_position);
         OMV.Vector3 upForce = OMV.Vector3.Zero;
-        if (Position.Z < terrainHeight)
+        if (RawPosition.Z < terrainHeight)
         {
             DetailLog("{0},BSPrim.PositionAdjustUnderGround,call,pos={1},terrain={2}", LocalID, _position, terrainHeight);
             float targetHeight = terrainHeight + (Size.Z / 2f);
             // Upforce proportional to the distance away from the terrain. Correct the error in 1 sec.
-            upForce.Z = (terrainHeight - Position.Z) * 1f;
+            upForce.Z = (terrainHeight - RawPosition.Z) * 1f;
             ret = true;
         }
 
         if ((CurrentCollisionFlags & CollisionFlags.BS_FLOATS_ON_WATER) != 0)
         {
-            float waterHeight = PhysicsScene.GetWaterLevelAtXYZ(_position);
+            float waterHeight = PhysicsScene.TerrainManager.GetWaterLevelAtXYZ(_position);
             // TODO: a floating motor so object will bob in the water
-            if (Math.Abs(Position.Z - waterHeight) > 0.1f)
+            if (Math.Abs(RawPosition.Z - waterHeight) > 0.1f)
             {
                 // Upforce proportional to the distance away from the water. Correct the error in 1 sec.
-                upForce.Z = (waterHeight - Position.Z) * 1f;
+                upForce.Z = (waterHeight - RawPosition.Z) * 1f;
                 ret = true;
             }
         }
 
-        // TODO: check for out of bounds
-
         // The above code computes a force to apply to correct any out-of-bounds problems. Apply same.
+        // TODO: This should be intergrated with a geneal physics action mechanism.
+        // TODO: This should be moderated with PID'ness.
         if (ret)
         {
-            PhysicsScene.TaintedObject(inTaintTime, "BSPrim.PositionSanityCheck:belowTerrain", delegate()
-            {
-                // Apply upforce and overcome gravity.
-                ForceVelocity = ForceVelocity + upForce - PhysicsScene.DefaultGravity;
-            });
+            // Apply upforce and overcome gravity.
+            OMV.Vector3 correctionForce = upForce - PhysicsScene.DefaultGravity;
+            DetailLog("{0},BSPrim.PositionSanityCheck,applyForce,pos={1},upForce={2},correctionForce={3}", LocalID, _position, upForce, correctionForce);
+            AddForce(correctionForce, false, inTaintTime);
         }
         return ret;
     }
@@ -408,7 +437,8 @@ public sealed class BSPrim : BSPhysObject
             PhysicsScene.TaintedObject("BSPrim.setForce", delegate()
             {
                 // DetailLog("{0},BSPrim.setForce,taint,force={1}", LocalID, _force);
-                BulletSimAPI.SetObjectForce2(PhysBody.ptr, _force);
+                if (PhysBody.HasPhysicalBody)
+                    BulletSimAPI.SetObjectForce2(PhysBody.ptr, _force);
             });
         }
     }
@@ -502,15 +532,18 @@ public sealed class BSPrim : BSPhysObject
             PhysicsScene.TaintedObject("BSPrim.setVelocity", delegate()
             {
                 // DetailLog("{0},BSPrim.SetVelocity,taint,vel={1}", LocalID, _velocity);
-                BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
+                ForceVelocity = _velocity;
             });
         }
     }
     public override OMV.Vector3 ForceVelocity {
         get { return _velocity; }
         set {
+            PhysicsScene.AssertInTaintTime("BSPrim.ForceVelocity");
+
             _velocity = value;
-            BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
+            if (PhysBody.HasPhysicalBody)
+                BulletSimAPI.SetLinearVelocity2(PhysBody.ptr, _velocity);
         }
     }
     public override OMV.Vector3 Torque {
@@ -537,23 +570,32 @@ public sealed class BSPrim : BSPhysObject
     }
     public override OMV.Quaternion Orientation {
         get {
+            /* NOTE: this refetch is not necessary. The simulator knows about linkset children
+             *    and does not fetch this position info for children. Thus this is commented out.
             // Children move around because tied to parent. Get a fresh value.
             if (!Linkset.IsRoot(this))
             {
-                _orientation = Linkset.Orientation(this);
+                _orientation = Linkset.OrientationGet(this);
             }
+             */
             return _orientation;
         }
         set {
             if (_orientation == value)
                 return;
             _orientation = value;
-            // TODO: what does it mean if a child in a linkset changes its orientation? Rebuild the constraint?
+
+            // A linkset might need to know if a component information changed.
+            Linkset.UpdateProperties(this, false);
+
             PhysicsScene.TaintedObject("BSPrim.setOrientation", delegate()
             {
-                // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
-                // DetailLog("{0},BSPrim.setOrientation,taint,pos={1},orient={2}", LocalID, _position, _orientation);
-                BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+                if (PhysBody.HasPhysicalBody)
+                {
+                    // _position = BulletSimAPI.GetObjectPosition2(PhysicsScene.World.ptr, BSBody.ptr);
+                    // DetailLog("{0},BSPrim.setOrientation,taint,pos={1},orient={2}", LocalID, _position, _orientation);
+                    BulletSimAPI.SetTranslation2(PhysBody.ptr, _position, _orientation);
+                }
             });
         }
     }
@@ -644,10 +686,7 @@ public sealed class BSPrim : BSPhysObject
         BulletSimAPI.UpdateSingleAabb2(PhysicsScene.World.ptr, PhysBody.ptr);
 
         // Collision filter can be set only when the object is in the world
-        if (PhysBody.collisionFilter != 0 || PhysBody.collisionMask != 0)
-        {
-            BulletSimAPI.SetCollisionFilterMask2(PhysBody.ptr, (uint)PhysBody.collisionFilter, (uint)PhysBody.collisionMask);
-        }
+        PhysBody.ApplyCollisionMask();
 
         // Recompute any linkset parameters.
         // When going from non-physical to physical, this re-enables the constraints that
@@ -672,8 +711,12 @@ public sealed class BSPrim : BSPhysObject
             CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(PhysBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
             // Stop all movement
             ZeroMotion(true);
-            // Center of mass is at the center of the object
-            // DEBUG DEBUG BulletSimAPI.SetCenterOfMassByPosRot2(Linkset.LinksetRoot.PhysBody.ptr, _position, _orientation);
+
+            // Set various physical properties so other object interact properly
+            MaterialAttributes matAttrib = BSMaterials.GetAttributes(Material, false);
+            BulletSimAPI.SetFriction2(PhysBody.ptr, matAttrib.friction);
+            BulletSimAPI.SetRestitution2(PhysBody.ptr, matAttrib.restitution);
+
             // Mass is zero which disables a bunch of physics stuff in Bullet
             UpdatePhysicalMassProperties(0f);
             // Set collision detection parameters
@@ -682,24 +725,27 @@ public sealed class BSPrim : BSPhysObject
                 BulletSimAPI.SetCcdMotionThreshold2(PhysBody.ptr, PhysicsScene.Params.ccdMotionThreshold);
                 BulletSimAPI.SetCcdSweptSphereRadius2(PhysBody.ptr, PhysicsScene.Params.ccdSweptSphereRadius);
             }
-            // There can be special things needed for implementing linksets
-            Linkset.MakeStatic(this);
+
             // The activation state is 'disabled' so Bullet will not try to act on it.
-            BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.DISABLE_SIMULATION);
+            // BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.DISABLE_SIMULATION);
             // Start it out sleeping and physical actions could wake it up.
-            // BulletSimAPI.ForceActivationState2(BSBody.ptr, ActivationState.ISLAND_SLEEPING);
+            BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.ISLAND_SLEEPING);
+
+            // This collides like a static object
+            PhysBody.collisionType = CollisionType.Static;
 
-            PhysBody.collisionFilter = CollisionFilterGroups.StaticObjectFilter;
-            PhysBody.collisionMask = CollisionFilterGroups.StaticObjectMask;
+            // There can be special things needed for implementing linksets
+            Linkset.MakeStatic(this);
         }
         else
         {
             // Not a Bullet static object
             CurrentCollisionFlags = BulletSimAPI.RemoveFromCollisionFlags2(PhysBody.ptr, CollisionFlags.CF_STATIC_OBJECT);
 
-            // Set various physical properties so internal dynamic properties will get computed correctly as they are set
-            BulletSimAPI.SetFriction2(PhysBody.ptr, PhysicsScene.Params.defaultFriction);
-            BulletSimAPI.SetRestitution2(PhysBody.ptr, PhysicsScene.Params.defaultRestitution);
+            // Set various physical properties so other object interact properly
+            MaterialAttributes matAttrib = BSMaterials.GetAttributes(Material, true);
+            BulletSimAPI.SetFriction2(PhysBody.ptr, matAttrib.friction);
+            BulletSimAPI.SetRestitution2(PhysBody.ptr, matAttrib.restitution);
 
             // per http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?t=3382
             // Since this can be called multiple times, only zero forces when becoming physical
@@ -727,16 +773,15 @@ public sealed class BSPrim : BSPhysObject
             BulletSimAPI.SetSleepingThresholds2(PhysBody.ptr, PhysicsScene.Params.linearSleepingThreshold, PhysicsScene.Params.angularSleepingThreshold);
             BulletSimAPI.SetContactProcessingThreshold2(PhysBody.ptr, PhysicsScene.Params.contactProcessingThreshold);
 
-            // There might be special things needed for implementing linksets.
-            Linkset.MakeDynamic(this);
+            // This collides like an object.
+            PhysBody.collisionType = CollisionType.Dynamic;
 
             // Force activation of the object so Bullet will act on it.
             // Must do the ForceActivationState2() to overcome the DISABLE_SIMULATION from static objects.
             BulletSimAPI.ForceActivationState2(PhysBody.ptr, ActivationState.ACTIVE_TAG);
-            // BulletSimAPI.Activate2(BSBody.ptr, true);
 
-            PhysBody.collisionFilter = CollisionFilterGroups.ObjectFilter;
-            PhysBody.collisionMask = CollisionFilterGroups.ObjectMask;
+            // There might be special things needed for implementing linksets.
+            Linkset.MakeDynamic(this);
         }
     }
 
@@ -763,8 +808,9 @@ public sealed class BSPrim : BSPhysObject
                 m_log.ErrorFormat("{0} MakeSolid: physical body of wrong type for non-solidness. id={1}, type={2}", LogHeader, LocalID, bodyType);
             }
             CurrentCollisionFlags = BulletSimAPI.AddToCollisionFlags2(PhysBody.ptr, CollisionFlags.CF_NO_CONTACT_RESPONSE);
-            PhysBody.collisionFilter = CollisionFilterGroups.VolumeDetectFilter;
-            PhysBody.collisionMask = CollisionFilterGroups.VolumeDetectMask;
+
+            // Change collision info from a static object to a ghosty collision object
+            PhysBody.collisionType = CollisionType.VolumeDetect;
         }
     }
 
@@ -839,15 +885,6 @@ public sealed class BSPrim : BSPhysObject
     }
     public override OMV.Vector3 RotationalVelocity {
         get {
-            /*
-            OMV.Vector3 pv = OMV.Vector3.Zero;
-            // if close to zero, report zero
-            // This is copied from ODE but I'm not sure why it returns zero but doesn't
-            //    zero the property in the physics engine.
-            if (_rotationalVelocity.ApproxEquals(pv, 0.2f))
-                return pv;
-             */
-
             return _rotationalVelocity;
         }
         set {
@@ -856,7 +893,8 @@ public sealed class BSPrim : BSPhysObject
             PhysicsScene.TaintedObject("BSPrim.setRotationalVelocity", delegate()
             {
                 DetailLog("{0},BSPrim.SetRotationalVel,taint,rotvel={1}", LocalID, _rotationalVelocity);
-                BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
+                if (PhysBody.HasPhysicalBody)
+                    BulletSimAPI.SetAngularVelocity2(PhysBody.ptr, _rotationalVelocity);
             });
         }
     }
@@ -891,8 +929,11 @@ public sealed class BSPrim : BSPhysObject
             _buoyancy = value;
             // DetailLog("{0},BSPrim.setForceBuoyancy,taint,buoy={1}", LocalID, _buoyancy);
             // Buoyancy is faked by changing the gravity applied to the object
-            float grav = PhysicsScene.Params.gravity * (1f - _buoyancy);
-            BulletSimAPI.SetGravity2(PhysBody.ptr, new OMV.Vector3(0f, 0f, grav));
+            if (PhysBody.HasPhysicalBody)
+            {
+                float grav = PhysicsScene.Params.gravity * (1f - _buoyancy);
+                BulletSimAPI.SetGravity2(PhysBody.ptr, new OMV.Vector3(0f, 0f, grav));
+            }
         }
     }
 
@@ -960,7 +1001,8 @@ public sealed class BSPrim : BSPhysObject
             }
             DetailLog("{0},BSPrim.AddForce,taint,force={1}", LocalID, fSum);
             if (fSum != OMV.Vector3.Zero)
-                BulletSimAPI.ApplyCentralForce2(PhysBody.ptr, fSum);
+                if (PhysBody.HasPhysicalBody)
+                    BulletSimAPI.ApplyCentralForce2(PhysBody.ptr, fSum);
         });
     }
 
@@ -971,7 +1013,8 @@ public sealed class BSPrim : BSPhysObject
         PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ApplyForceImpulse", delegate()
         {
             DetailLog("{0},BSPrim.ApplyForceImpulse,taint,tImpulse={1}", LocalID, applyImpulse);
-            BulletSimAPI.ApplyCentralImpulse2(PhysBody.ptr, applyImpulse);
+            if (PhysBody.HasPhysicalBody)
+                BulletSimAPI.ApplyCentralImpulse2(PhysBody.ptr, applyImpulse);
         });
     }
 
@@ -1007,18 +1050,23 @@ public sealed class BSPrim : BSPhysObject
             DetailLog("{0},BSPrim.AddAngularForce,taint,aForce={1}", LocalID, fSum);
             if (fSum != OMV.Vector3.Zero)
             {
-                BulletSimAPI.ApplyTorque2(PhysBody.ptr, fSum);
+                if (PhysBody.HasPhysicalBody)
+                    BulletSimAPI.ApplyTorque2(PhysBody.ptr, fSum);
                 _torque = fSum;
             }
         });
     }
     // A torque impulse.
+    // ApplyTorqueImpulse adds torque directly to the angularVelocity.
+    // AddAngularForce accumulates the force and applied it to the angular velocity all at once.
+    // Computed as: angularVelocity += impulse * inertia;
     public void ApplyTorqueImpulse(OMV.Vector3 impulse, bool inTaintTime)
     {
         OMV.Vector3 applyImpulse = impulse;
         PhysicsScene.TaintedObject(inTaintTime, "BSPrim.ApplyTorqueImpulse", delegate()
         {
-            BulletSimAPI.ApplyTorqueImpulse2(PhysBody.ptr, applyImpulse);
+            if (PhysBody.HasPhysicalBody)
+                BulletSimAPI.ApplyTorqueImpulse2(PhysBody.ptr, applyImpulse);
         });
     }
 
@@ -1326,7 +1374,7 @@ public sealed class BSPrim : BSPhysObject
     // Rebuild the geometry and object.
     // This is called when the shape changes so we need to recreate the mesh/hull.
     // Called at taint-time!!!
-    private void CreateGeomAndObject(bool forceRebuild)
+    public void CreateGeomAndObject(bool forceRebuild)
     {
         // If this prim is part of a linkset, we must remove and restore the physical
         //    links if the body is rebuilt.
@@ -1336,12 +1384,11 @@ public sealed class BSPrim : BSPhysObject
         // Create the correct physical representation for this type of object.
         // Updates PhysBody and PhysShape with the new information.
         // Ignore 'forceRebuild'. This routine makes the right choices and changes of necessary.
-        // Returns 'true' if either the body or the shape was changed.
         PhysicsScene.Shapes.GetBodyAndShape(false, PhysicsScene.World, this, null, delegate(BulletBody dBody)
         {
             // Called if the current prim body is about to be destroyed.
             // Remove all the physical dependencies on the old body.
-            // (Maybe someday make the changing of BSShape an event handled by BSLinkset.)
+            // (Maybe someday make the changing of BSShape an event to be subscribed to by BSLinkset, ...)
             needToRestoreLinkset = Linkset.RemoveBodyDependencies(this);
             needToRestoreVehicle = _vehicle.RemoveBodyDependencies(this);
         });
@@ -1381,54 +1428,16 @@ public sealed class BSPrim : BSPhysObject
 
     public override void UpdateProperties(EntityProperties entprop)
     {
-        /*
-        UpdatedProperties changed = 0;
-        // assign to the local variables so the normal set action does not happen
-        // if (_position != entprop.Position)
-        if (!_position.ApproxEquals(entprop.Position, POSITION_TOLERANCE))
-        {
-            _position = entprop.Position;
-            changed |= UpdatedProperties.Position;
-        }
-        // if (_orientation != entprop.Rotation)
-        if (!_orientation.ApproxEquals(entprop.Rotation, ROTATION_TOLERANCE))
-        {
-            _orientation = entprop.Rotation;
-            changed |= UpdatedProperties.Rotation;
-        }
-        // if (_velocity != entprop.Velocity)
-        if (!_velocity.ApproxEquals(entprop.Velocity, VELOCITY_TOLERANCE))
-        {
-            _velocity = entprop.Velocity;
-            changed |= UpdatedProperties.Velocity;
-        }
-        // if (_acceleration != entprop.Acceleration)
-        if (!_acceleration.ApproxEquals(entprop.Acceleration, ACCELERATION_TOLERANCE))
-        {
-            _acceleration = entprop.Acceleration;
-            changed |= UpdatedProperties.Acceleration;
-        }
-        // if (_rotationalVelocity != entprop.RotationalVelocity)
-        if (!_rotationalVelocity.ApproxEquals(entprop.RotationalVelocity, ROTATIONAL_VELOCITY_TOLERANCE))
-        {
-            _rotationalVelocity = entprop.RotationalVelocity;
-            changed |= UpdatedProperties.RotationalVel;
-        }
-        if (changed != 0)
+        // Updates only for individual prims and for the root object of a linkset.
+        if (Linkset.IsRoot(this))
         {
-            // Only update the position of single objects and linkset roots
-            if (Linkset.IsRoot(this))
+            // A temporary kludge to suppress the rotational effects introduced on vehicles by Bullet
+            // TODO: handle physics introduced by Bullet with computed vehicle physics.
+            if (_vehicle.IsActive)
             {
-                base.RequestPhysicsterseUpdate();
+                entprop.RotationalVelocity = OMV.Vector3.Zero;
             }
-        }
-        */
 
-        // Don't check for damping here -- it's done in BulletSim and SceneObjectPart.
-
-        // Updates only for individual prims and for the root object of a linkset.
-        if (Linkset.IsRoot(this))
-        {
             // Assign directly to the local variables so the normal set action does not happen
             _position = entprop.Position;
             _orientation = entprop.Rotation;
@@ -1437,21 +1446,19 @@ public sealed class BSPrim : BSPhysObject
             _rotationalVelocity = entprop.RotationalVelocity;
 
             // The sanity check can change the velocity and/or position.
-            if (PositionSanityCheck(true))
+            if (IsPhysical && PositionSanityCheck(true))
             {
                 entprop.Position = _position;
                 entprop.Velocity = _velocity;
             }
 
-            // remember the current and last set values
-            LastEntityProperties = CurrentEntityProperties;
-            CurrentEntityProperties = entprop;
-
-            OMV.Vector3 direction = OMV.Vector3.UnitX * _orientation;
+            OMV.Vector3 direction = OMV.Vector3.UnitX * _orientation;   // DEBUG DEBUG DEBUG
             DetailLog("{0},BSPrim.UpdateProperties,call,pos={1},orient={2},dir={3},vel={4},rotVel={5}",
                     LocalID, _position, _orientation, direction, _velocity, _rotationalVelocity);
 
-            // BulletSimAPI.DumpRigidBody2(PhysicsScene.World.ptr, BSBody.ptr);   // DEBUG DEBUG DEBUG
+            // remember the current and last set values
+            LastEntityProperties = CurrentEntityProperties;
+            CurrentEntityProperties = entprop;
 
             base.RequestPhysicsterseUpdate();
         }
@@ -1466,7 +1473,7 @@ public sealed class BSPrim : BSPhysObject
              */
 
         // The linkset implimentation might want to know about this.
-        Linkset.UpdateProperties(this);
+        Linkset.UpdateProperties(this, true);
     }
 }
 }