BulletSim: pass up and report the real collision penetration.

OpenSim/Region/Physics/BulletSPlugin/BSApiTemplate.cs

@@ -130,6 +130,7 @@ public struct CollisionDesc
     public uint bID;
     public Vector3 point;
     public Vector3 normal;
+    public float penetration;
 }
 [StructLayout(LayoutKind.Sequential)]
 public struct EntityProperties

OpenSim/Region/Physics/BulletSPlugin/BSScene.cs

@@ -557,8 +557,9 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
                 uint cB = m_collisionArray[ii].bID;
                 Vector3 point = m_collisionArray[ii].point;
                 Vector3 normal = m_collisionArray[ii].normal;
-                SendCollision(cA, cB, point, normal, 0.01f);
-                SendCollision(cB, cA, point, -normal, 0.01f);
+                float penetration = m_collisionArray[ii].penetration;
+                SendCollision(cA, cB, point, normal, penetration);
+                SendCollision(cB, cA, point, -normal, penetration);
             }
         }