this->TransformPointToContinuousIndex( point, m_Index );
// NOTE: if the support region does not lie totally within the grid
// we assume zero displacement and return the input point
if ( !this->InsideValidRegion( m_Index ) )
{
this->TransformPointToContinuousIndex( point, m_Index );
// NOTE: if the support region does not lie totally within the grid
// we assume zero displacement and return the input point
if ( !this->InsideValidRegion( m_Index ) )
{