BulletSim: Way too many changes in one commit.

Many changes to BSDynamic for readability and commentary.
Linkset hacking for vehicles: don't over mass the root prim.
Add parameter for link constraint solver iterations.
Correct uses of timestep in timescale calculations for vehicles.
Reorganize code/logic for making objects static and dynamic for readability
    and use of API2.
Changed most calls in BSPrim to use API2 calls (the new way).
Avatars do not generate default Bullet collision events but do call up
    to the simulator for every avatar. Reduces overhead.
Objects added to collision list only if they are processing collisions.
    Reduces overhead especially for large numbers of avatars.
Generalize call for water height to GetWaterHeightAtXYZ().
Catch and correct exception getting terrain height when out of bounds.
Correct race condition in Terrain Manager where creation wasn't at taint-time.
Add API calls for constructing compound shapes.
Move NeedsMeshing() logic into object class.
Reorganize logic for object meshing to reduce rebuilding of meshs/hulls.

1 files changed, 25 insertions, 7 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
index 5f6601d..dc1de6c 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSLinkset.cs
@@ -206,7 +206,7 @@ public class BSLinkset
     //   its internal properties.
     public void Refresh(BSPhysObject requestor)
     {
-        // If there are no children, there aren't any constraints to recompute
+        // If there are no children, there can't be any constraints to recompute
         if (!HasAnyChildren)
             return;
 
@@ -225,11 +225,12 @@ public class BSLinkset
     //    from a linkset to make sure the constraints know about the new mass and
     //    geometry.
     // Must only be called at taint time!!
-    private bool RecomputeLinksetConstraintVariables()
+    private void RecomputeLinksetConstraintVariables()
     {
         float linksetMass = LinksetMass;
         lock (m_linksetActivityLock)
         {
+            bool somethingMissing = false;
             foreach (BSPhysObject child in m_children)
             {
                 BSConstraint constrain;
@@ -241,16 +242,29 @@ public class BSLinkset
                 }
                 else
                 {
-                    // Non-fatal error that can happen when children are being added to the linkset but
+                    // Non-fatal error that happens when children are being added to the linkset but
                     //    their constraints have not been created yet.
                     // Caused by the fact that m_children is built at run time but building constraints
                     //    happens at taint time.
-                    // m_physicsScene.Logger.ErrorFormat("{0} RecomputeLinksetConstraintVariables: constraint not found for root={1}, child={2}",
-                    //                                 LogHeader, m_linksetRoot.Body.ID, child.Body.ID);
+                    somethingMissing = true;
+                    break;
                 }
             }
+
+            // If the whole linkset is not here, doesn't make sense to recompute the root prim now.
+            if (!somethingMissing)
+            {
+                // The root prim takes on the weight of the whole linkset
+                /*
+                OMV.Vector3 inertia = BulletSimAPI.CalculateLocalInertia2(LinksetRoot.BSShape.Ptr, linksetMass);
+                BulletSimAPI.SetMassProps2(LinksetRoot.BSBody.Ptr, linksetMass, inertia);
+                OMV.Vector3 centerOfMass = ComputeLinksetCenterOfMass();
+                BulletSimAPI.SetCenterOfMassByPosRot2(LinksetRoot.BSBody.Ptr, centerOfMass, OMV.Quaternion.Identity);
+                BulletSimAPI.UpdateInertiaTensor2(LinksetRoot.BSBody.Ptr);
+                 */
+            }
         }
-        return false;
+        return;
     }
 
     // I am the root of a linkset and a new child is being added
@@ -296,9 +310,9 @@ public class BSLinkset
                 DetailLog("{0},RemoveChildFromLinkset,taint,child={1}", m_linksetRoot.LocalID, child.LocalID);
 
                 PhysicallyUnlinkAChildFromRoot(rootx, childx);
+                RecomputeLinksetConstraintVariables();
             });
 
-            RecomputeLinksetConstraintVariables();
         }
         else
         {
@@ -377,6 +391,10 @@ public class BSLinkset
                         PhysicsScene.Params.linkConstraintTransMotorMaxVel,
                         PhysicsScene.Params.linkConstraintTransMotorMaxForce);
         constrain.SetCFMAndERP(PhysicsScene.Params.linkConstraintCFM, PhysicsScene.Params.linkConstraintERP);
+        if (PhysicsScene.Params.linkConstraintSolverIterations != 0f)
+        {
+            constrain.SetSolverIterations(PhysicsScene.Params.linkConstraintSolverIterations);
+        }
 
         RecomputeLinksetConstraintVariables();
     }