add fixme for extract volume in 2D (orientation of quads)

Plugin/Levelset.cpp

-// $Id: Levelset.cpp,v 1.26 2005-03-25 12:13:23 remacle Exp $
+// $Id: Levelset.cpp,v 1.27 2005-10-19 15:45:10 geuzaine Exp $
 //
 // Copyright (C) 1997-2005 C. Geuzaine, J.-F. Remacle
 //
@@ -376,6 +376,8 @@ int GMSH_LevelsetPlugin::zeroLevelset(int timeStep,
 
   // if we compute isovolumes, add the nodes on the chosen side 
   if(_extractVolume){
+    // FIXME: when cutting 2D views, the elts we get can have the wrong
+    // orientation
     int nbCut = np;
     for(int k = 0; k < nbNod; k++){
       if((_extractVolume < 0. && levels[k] < 0.0) ||