BulletSim: allow changing position and rotation of a child of a linkset

without rebuilding the whole compound shape. Should make vehicles move
smoother.

OpenSim/Region/Physics/BulletSPlugin/BSCharacter.cs

@@ -899,7 +899,7 @@ public sealed class BSCharacter : BSPhysObject
         CurrentEntityProperties = entprop;
 
         // Tell the linkset about value changes
-        Linkset.UpdateProperties(this, true);
+        Linkset.UpdateProperties(UpdatedProperties.EntPropUpdates, this);
 
         // Avatars don't report their changes the usual way. Changes are checked for in the heartbeat loop.
         // base.RequestPhysicsterseUpdate();

OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs

@@ -252,7 +252,7 @@ public abstract class BSLinkset
     //      of the linkset is received.
     // Passed flag is update came from physics engine (true) or the user (false).
     // Called at taint-time!!
-    public abstract void UpdateProperties(BSPhysObject physObject, bool physicalUpdate);
+    public abstract void UpdateProperties(UpdatedProperties whichUpdated, BSPhysObject physObject);
 
     // Routine used when rebuilding the body of the root of the linkset
     // Destroy all the constraints have have been made to root.

OpenSim/Region/Physics/BulletSPlugin/BSLinksetCompound.cs

@@ -51,6 +51,21 @@ sealed class BSLinksetCompoundInfo : BSLinksetInfo
         OffsetFromCenterOfMass = p;
         OffsetRot = r;
     }
+    // 'centerDisplacement' is the distance from the root the the center-of-mass (Bullet 'zero' of the shape)
+    public BSLinksetCompoundInfo(int indx, BSPhysObject root, BSPhysObject child, OMV.Vector3 centerDisplacement)
+    {
+        // Each child position and rotation is given relative to the center-of-mass.
+        OMV.Quaternion invRootOrientation = OMV.Quaternion.Inverse(root.RawOrientation);
+        OMV.Vector3 displacementFromRoot = (child.RawPosition - root.RawPosition) * invRootOrientation;
+        OMV.Vector3 displacementFromCOM = displacementFromRoot - centerDisplacement;
+        OMV.Quaternion displacementRot = child.RawOrientation * invRootOrientation;
+
+        // Save relative position for recomputing child's world position after moving linkset.
+        Index = indx;
+        OffsetFromRoot = displacementFromRoot;
+        OffsetFromCenterOfMass = displacementFromCOM;
+        OffsetRot = displacementRot;
+    }
     public override void Clear()
     {
         Index = 0;
@@ -182,24 +197,71 @@ public sealed class BSLinksetCompound : BSLinkset
 
     // 'physicalUpdate' is true if these changes came directly from the physics engine. Don't need to rebuild then.
     // Called at taint-time.
-    public override void UpdateProperties(BSPhysObject updated, bool physicalUpdate)
+    public override void UpdateProperties(UpdatedProperties whichUpdated, BSPhysObject updated)
     {
         // The user moving a child around requires the rebuilding of the linkset compound shape
         // One problem is this happens when a border is crossed -- the simulator implementation
-        //    is to store the position into the group which causes the move of the object
+        //    stores the position into the group which causes the move of the object
         //    but it also means all the child positions get updated.
         //    What would cause an unnecessary rebuild so we make sure the linkset is in a
         //    region before bothering to do a rebuild.
-        if (!IsRoot(updated) 
+        if (!IsRoot(updated) && PhysicsScene.TerrainManager.IsWithinKnownTerrain(LinksetRoot.RawPosition))
-                && !physicalUpdate 
-                && PhysicsScene.TerrainManager.IsWithinKnownTerrain(LinksetRoot.RawPosition))
         {
-            // TODO: replace this with are calculation of the child prim's orientation and pos.
+            // If a child of the linkset is updating only the position or rotation, that can be done
-            // TODO: for the moment, don't rebuild the compound shape.
+            //    without rebuilding the linkset.
-            //    This is often just the car turning its wheels. When we can just reorient the one
+            // If a handle for the child can be fetch, we update the child here. If a rebuild was
-            //    member shape of the compound shape, the overhead of rebuilding won't be a problem.
+            //    scheduled by someone else, the rebuild will just replace this setting.
-            // updated.LinksetInfo = null;
+
-            // ScheduleRebuild(updated);
+            bool updatedChild = false;
+            // Anything other than updating position or orientation usually means a physical update
+            //     and that is caused by us updating the object.
+            if ((whichUpdated & ~(UpdatedProperties.Position | UpdatedProperties.Orientation)) == 0)
+            {
+                // Gather the child info. It might not be there if the linkset is in transition.
+                BSLinksetCompoundInfo lsi = updated.LinksetInfo as BSLinksetCompoundInfo;
+                if (LinksetRoot.PhysShape.HasPhysicalShape && lsi != null)
+                {
+                    if (PhysicsScene.PE.IsCompound(LinksetRoot.PhysShape))
+                    {
+                        BulletShape linksetChildShape = PhysicsScene.PE.GetChildShapeFromCompoundShapeIndex(LinksetRoot.PhysShape, lsi.Index);
+                        if (linksetChildShape.HasPhysicalShape)
+                        {
+                            // Compute the offset from the center-of-gravity
+                            BSLinksetCompoundInfo newLsi = new BSLinksetCompoundInfo(lsi.Index, LinksetRoot, updated, LinksetRoot.PositionDisplacement);
+                            PhysicsScene.PE.UpdateChildTransform(LinksetRoot.PhysShape, lsi.Index,
+                                                                        newLsi.OffsetFromCenterOfMass,
+                                                                        newLsi.OffsetRot,
+                                                                        true /* shouldRecalculateLocalAabb */);
+                            DetailLog("{0},BSLinksetCompound.UpdateProperties,changeChildPosRot,whichUpdated={1}newLsi={2}",
+                                                                        updated.LocalID, whichUpdated, newLsi);
+                            updated.LinksetInfo = newLsi;
+                            updatedChild = true;
+                        }
+                        else    // DEBUG DEBUG
+                        {       // DEBUG DEBUG
+                            DetailLog("{0},BSLinksetCompound.UpdateProperties,couldNotUpdateChild,noChildShape,shape={1}",
+                                                                        updated.LocalID, linksetChildShape);
+                        }       // DEBUG DEBUG
+                    }
+                    else    // DEBUG DEBUG
+                    {       // DEBUG DEBUG
+                        DetailLog("{0},BSLinksetCompound.UpdateProperties,couldNotUpdateChild,notCompound", updated.LocalID);
+                    }       // DEBUG DEBUG
+                }
+                else    // DEBUG DEBUG
+                {       // DEBUG DEBUG
+                    DetailLog("{0},BSLinksetCompound.UpdateProperties,couldNotUpdateChild,rootPhysShape={1},lsi={2}",
+                                updated.LocalID, LinksetRoot.PhysShape, lsi == null ? "NULL" : lsi.ToString());
+                }       // DEBUG DEBUG
+                if (!updatedChild)
+                {
+                    // If couldn't do the individual child, the linkset needs a rebuild to incorporate the new child info.
+                    DetailLog("{0},BSLinksetCompound.UpdateProperties,couldNotUpdateChild.schedulingRebuild,whichUpdated={1}",
+                                                                    updated.LocalID, whichUpdated);
+                    updated.LinksetInfo = null; // setting to 'null' causes relative position to be recomputed.
+                    ScheduleRebuild(updated);
+                }
+            }
         }
     }
 
@@ -372,15 +434,7 @@ public sealed class BSLinksetCompound : BSLinkset
                     BSLinksetCompoundInfo lci = cPrim.LinksetInfo as BSLinksetCompoundInfo;
                     if (lci == null)
                     {
-                        // Each child position and rotation is given relative to the center-of-mass.
+                        lci = new BSLinksetCompoundInfo(memberIndex, LinksetRoot, cPrim, centerDisplacement);
-                        OMV.Quaternion invRootOrientation = OMV.Quaternion.Inverse(LinksetRoot.RawOrientation);
-                        OMV.Vector3 displacementFromRoot = (cPrim.RawPosition - LinksetRoot.RawPosition) * invRootOrientation;
-                        OMV.Vector3 displacementFromCOM = displacementFromRoot - centerDisplacement;
-                        OMV.Quaternion displacementRot = cPrim.RawOrientation * invRootOrientation;
-
-                        // Save relative position for recomputing child's world position after moving linkset.
-                        lci = new BSLinksetCompoundInfo(memberIndex, displacementFromCOM, displacementRot);
-                        lci.OffsetFromRoot = displacementFromRoot;
                         cPrim.LinksetInfo = lci;
                         DetailLog("{0},BSLinksetCompound.RecomputeLinksetCompound,creatingRelPos,lci={1}", cPrim.LocalID, lci);
                     }

OpenSim/Region/Physics/BulletSPlugin/BSLinksetConstraints.cs

@@ -83,7 +83,7 @@ public sealed class BSLinksetConstraints : BSLinkset
     }
 
     // Called at taint-time!!
-    public override void UpdateProperties(BSPhysObject updated, bool inTaintTime)
+    public override void UpdateProperties(UpdatedProperties whichUpdated, BSPhysObject pObj)
     {
         // Nothing to do for constraints on property updates
     }

OpenSim/Region/Physics/BulletSPlugin/BSPhysObject.cs

@@ -55,6 +55,16 @@ namespace OpenSim.Region.Physics.BulletSPlugin
  * BS.ApplyCentralForce BS.ApplyTorque              
  */
 
+// Flags used to denote which properties updates when making UpdateProperties calls to linksets, etc.
+public enum UpdatedProperties : uint
+{
+    Position                = 1 << 0,
+    Orientation             = 1 << 1,
+    Velocity                = 1 << 2,
+    Acceleration            = 1 << 3,
+    RotationalVelocity      = 1 << 4,
+    EntPropUpdates          = Position | Orientation | Velocity | Acceleration | RotationalVelocity,
+}
 public abstract class BSPhysObject : PhysicsActor
 {
     protected BSPhysObject()

OpenSim/Region/Physics/BulletSPlugin/BSPrim.cs

@@ -311,13 +311,14 @@ public sealed class BSPrim : BSPhysObject
             _position = value;
             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);
                 ForcePosition = _position;
+
+                // A linkset might need to know if a component information changed.
+                Linkset.UpdateProperties(UpdatedProperties.Position, this);
+
             });
         }
     }
@@ -682,12 +683,13 @@ public sealed class BSPrim : BSPhysObject
                 return;
             _orientation = value;
 
-            // A linkset might need to know if a component information changed.
-            Linkset.UpdateProperties(this, false);
-
             PhysicsScene.TaintedObject("BSPrim.setOrientation", delegate()
             {
                 ForceOrientation = _orientation;
+
+                // A linkset might need to know if a component information changed.
+                Linkset.UpdateProperties(UpdatedProperties.Orientation, this);
+
             });
         }
     }
@@ -1686,7 +1688,7 @@ public sealed class BSPrim : BSPhysObject
              */
 
         // The linkset implimentation might want to know about this.
-        Linkset.UpdateProperties(this, true);
+        Linkset.UpdateProperties(UpdatedProperties.EntPropUpdates, this);
     }
 }
 }

OpenSim/Region/Physics/BulletSPlugin/BSScene.cs

@@ -846,8 +846,6 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
 
     #endregion // Taints
 
-    #region INI and command line parameter processing
-
     #region IPhysicsParameters
     // Get the list of parameters this physics engine supports
     public PhysParameterEntry[] GetParameterList()
@@ -944,8 +942,6 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
 
     #endregion IPhysicsParameters
 
-    #endregion Runtime settable parameters
-
     // Invoke the detailed logger and output something if it's enabled.
     public void DetailLog(string msg, params Object[] args)
     {

OpenSim/Region/Physics/BulletSPlugin/BulletSimTODO.txt

@@ -1,25 +1,20 @@
 CURRENT PRIORITIES
 =================================================
-Mantis 6040 script http://opensimulator.org/mantis/view.php?id=6040
+Child movement in linkset (don't rebuild linkset)
-	Msg Kayaker on OSGrid when working
+Vehicle angular vertical attraction
+vehicle angular banking
+Center-of-gravity
+Vehicle angular deflection
+	Preferred orientation angular correction fix
 when should angular and linear motor targets be zeroed? when selected?
 	Need a vehicle.clear()? Or an 'else' in prestep if not physical.
 Teravus llMoveToTarget script debug
 	Mixing of hover, buoyancy/gravity, moveToTarget, into one force
-Boats floating at proper level
 Nebadon vehicles turning funny in arena
 limitMotorUp calibration (more down?)
 llRotLookAt
 llLookAt
-Vehicle angular vertical attraction
-Vehicle angular deflection
-	Preferred orientation angular correction fix
-vehicle angular banking
 Avatars walking up stairs (HALF DONE)
-    Radius of the capsule affects ability to climb edges.
-Vehicle movement on terrain smoothness
-When is force introduced by SetForce removed? The prestep action could go forever.
-Boats float low in the water (DONE)
 Avatar movement
 	flying into a wall doesn't stop avatar who keeps appearing to move through the obstacle (DONE)
 	walking up stairs is not calibrated correctly (stairs out of Kepler cabin)
@@ -75,6 +70,7 @@ Incorporate inter-relationship of angular corrections. For instance, angularDefl
 
 GENERAL TODO LIST:
 =================================================
+llMoveToTarget objects are not effected by gravity until target is removed.
 Implement llSetPhysicalMaterial.
 	extend it with Center-of-mass, rolling friction, density
 Implement llSetForceAndTorque.
@@ -316,3 +312,11 @@ Remove HeightmapInfo from terrain specification (DONE)
 Surfboard go wonky when turning (DONE)
 	Angular motor direction is global coordinates rather than local coordinates?
 	(Resolution: made angular motor direction correct coordinate system)
+Mantis 6040 script http://opensimulator.org/mantis/view.php?id=6040 (DONE)
+	Msg Kayaker on OSGrid when working
+	(Resolution: LINEAR_DIRECTION is in vehicle coords. Test script does the
+	same in SL as in OS/BulletSim)
+Boats float low in the water (DONE)
+Boats floating at proper level (DONE)
+When is force introduced by SetForce removed? The prestep action could go forever. (DONE)
+	(Resolution: setForce registers a prestep action which keeps applying the force)