// Loop through all the known hulls and return the description based on the physical address.
 public static bool TryGetHullByPtr(BulletShape pShape, out BSShapeHull outHull)
 {
     bool ret = false;
     BSShapeHull foundDesc = null;
     lock (Hulls)
     {
         foreach (BSShapeHull sh in Hulls.Values)
         {
             if (sh.physShapeInfo.ReferenceSame(pShape))
             {
                 foundDesc = sh;
                 ret = true;
                 break;
             }
         }
     }
     outHull = foundDesc;
     return ret;
 }
        public static BSShape GetReference(BSScene physicsScene, bool forceRebuild, BSPhysObject prim)
        {
            float lod;
            UInt64 newHullKey = BSShape.ComputeShapeKey(prim.Size, prim.BaseShape, out lod);

            BSShapeHull retHull;
            bool foundHull = false;
            lock (Hulls)
                foundHull = Hulls.TryGetValue (newHullKey, out retHull);

            if (foundHull)
            {
                // The mesh has already been created. Return a new reference to same.
                retHull.IncrementReference();
            }
            else
            {
                retHull = new BSShapeHull(new BulletShape());
                // An instance of this mesh has not been created. Build and remember same.
                BulletShape newShape = retHull.CreatePhysicalHull(physicsScene, prim, newHullKey, prim.BaseShape, prim.Size, lod);

                // Check to see if hull was created (might require an asset).
                newShape = VerifyMeshCreated(physicsScene, newShape, prim);
                if (!newShape.isNativeShape || prim.AssetFailed())
                {
                    // If a mesh was what was created, remember the built shape for later sharing.
                    lock(Hulls)
                        Hulls.Add(newHullKey, retHull);
                }
                    retHull.physShapeInfo = newShape;
            }
            physicsScene.DetailLog("{0},BSShapeHull,getReference,hull={1},size={2},lod={3}", prim.LocalID, retHull,
                prim.Size, lod);
            return retHull;
        }