BulletSim: Fix crash on the destruction of physical linksets.

While fixing the above, add methods to physical body and shape pointer
wrapper so routines won't have to know that IntPtr.Zero means no
physical instance.
Fix problem with physical linksets failing after a few sits and
unsits by properly restoring child prom positions for compound
linksets after multiple selection and deselections.

1 files changed, 2 insertions, 2 deletions

diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
index 65fac00..6b1e304 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSConstraint.cs
@@ -57,7 +57,7 @@ public abstract class BSConstraint : IDisposable
         if (m_enabled)
         {
             m_enabled = false;
-            if (m_constraint.ptr != IntPtr.Zero)
+            if (m_constraint.HasPhysicalConstraint)
             {
                 bool success = BulletSimAPI.DestroyConstraint2(m_world.ptr, m_constraint.ptr);
                 m_world.physicsScene.DetailLog("{0},BSConstraint.Dispose,taint,id1={1},body1={2},id2={3},body2={4},success={5}",
@@ -65,7 +65,7 @@ public abstract class BSConstraint : IDisposable
                                     m_body1.ID, m_body1.ptr.ToString("X"),
                                     m_body2.ID, m_body2.ptr.ToString("X"),
                                     success);
-                m_constraint.ptr = System.IntPtr.Zero;
+                m_constraint.Clear();
             }
         }
     }