public static void ProcessPendingUpdates()
{
// clear the graveyard
_graveyardList.Clear();
// recalc the hashcode for each pass
for ( int i = 0; i < _dirtyList.Count; i++ )
{
Pass pass = (Pass)_dirtyList[ i ];
pass.RecalculateHash();
}
// clear out the dirty list
_dirtyList.Clear();
}