public SubtreeIterator(UsdPrimSubtreeRange range)
 {
     m_range  = range;
     m_cur    = range.GetStart();
     m_end    = range.GetEnd();
     m_primed = false;
 }
 public void Reset()
 {
     m_cur    = m_range.GetStart();
     m_primed = false;
 }