+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToDisplay ();
+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToNormalizedDisplay ();
+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToViewport ();
+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToNormalizedViewport ();
+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToView ();
+// _textActor->GetPositionCoordinate()->SetCoordinateSystemToWorld ();
+
+