diff --git a/src/meshlabplugins/edit_ocme/edit_ocme.cpp b/src/meshlabplugins/edit_ocme/edit_ocme.cpp
index 5b253e840..f621e8f57 100755
--- a/src/meshlabplugins/edit_ocme/edit_ocme.cpp
+++ b/src/meshlabplugins/edit_ocme/edit_ocme.cpp
@@ -105,6 +105,28 @@ vcg::Box3f GetViewVolumeBBox()
 
 }
 
+void OcmeEditPlugin::DrawCellsToEdit( ){
+
+		// render all the cells only on the stencil buffer
+		glColorMask(false,false,false,false);
+		for(unsigned int i  = 0; i < cells_to_edit.size(); ++i)
+			DrawCellSel(cells_to_edit[i]->key,1);
+		glColorMask(true,true,true,true);
+
+		glDepthFunc(GL_EQUAL);
+		glEnable(GL_BLEND);
+		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
+		glDisable(GL_LIGHTING);
+		glColor4b(0,0,0,127);
+		for(unsigned int i  = 0; i < cells_to_edit.size(); ++i)
+			DrawCellSel(cells_to_edit[i]->key,1);
+
+		glEnable(GL_LIGHTING);
+		glDisable(GL_BLEND);
+		glDepthFunc(GL_LESS);
+
+}
+
 void OcmeEditPlugin::Decorate(MeshModel &, GLArea * gla)
 {
 	rendering.lock();
@@ -193,13 +215,15 @@ void OcmeEditPlugin::Decorate(MeshModel &, GLArea * gla)
 		if ( vcg::Pick ( pickx, gla->height()-picky, all_keys,results, DrawCell /*DrawImpostor*/) )
 		{
 			CellKey cellkey  = *results[0];
-			cells_to_edit.push_back(ocme->GetCell(cellkey));
+			Cell *c = ocme->GetCell(cellkey,false);
+			cells_to_edit.push_back(c);
 		}
 	}
 
-	// draw the cells selected as sphere
-	for(unsigned int i  = 0; i < cells_to_edit.size(); ++i)
-		DrawCellSel(cells_to_edit[i]->key,2);
+	DrawCellsToEdit();
+//	// draw the cells selected as sphere
+//	for(unsigned int i  = 0; i < cells_to_edit.size(); ++i)
+//		DrawCellSel(cells_to_edit[i]->key,1);
 
 	if(isDragging)
 			DrawXORRect(gla);
@@ -243,6 +267,7 @@ void OcmeEditPlugin::updateButtonsState(){
 
 		odw->loadOcmPushButton->setEnabled(!ocme_loaded);
 		odw->createOcmPushButton->setEnabled(!ocme_loaded);
+		//odw->markEditablePushButton->setEnabled(!mm->cm.face.empty());
 }
 
 bool OcmeEditPlugin::StartEdit(MeshModel &/*m*/, GLArea *_gla )
@@ -265,6 +290,8 @@ bool OcmeEditPlugin::StartEdit(MeshModel &/*m*/, GLArea *_gla )
 	QObject::connect(odw->createOcmPushButton,SIGNAL(clicked()),this,SLOT(createOcm()));
 	QObject::connect(odw->closeOcmPushButton,SIGNAL(clicked()),this,SLOT(closeOcm()));
 	QObject::connect(odw->editPushButton,SIGNAL(clicked()),this,SLOT(edit()));
+	QObject::connect(odw->markEditablePushButton ,SIGNAL(clicked() ),this,SLOT( markEditable() ));
+	QObject::connect(odw->dropSelectionPushButton,SIGNAL(clicked()),this,SLOT(drop()));
 	QObject::connect(odw->commitPushButton,SIGNAL(clicked()),this,SLOT(commit()));
 	QObject::connect(odw->addPushButton,SIGNAL(clicked()),this,SLOT(add()));
 	QObject::connect(odw->fillAttrMeshPushButton ,SIGNAL(clicked() ),this,SLOT( fillMeshAttribute()));
@@ -472,6 +499,33 @@ void OcmeEditPlugin::createOcm(){
 
 	}
 }
+void OcmeEditPlugin::drop(){
+		ocme->renderCache.controller.pause();
+		mm->cm.Clear();
+		cells_to_edit.clear();
+		ocme->DropEdited();
+		ocme->renderCache.controller.resume();
+}
+
+void OcmeEditPlugin::markEditable(){
+		CMeshO::  PerVertexAttributeHandle<unsigned char>  lockedV =
+				vcg::tri::Allocator<CMeshO>::  GetPerVertexAttribute<unsigned char> (mm->cm,"ocme_locked");
+
+		CMeshO::  PerFaceAttributeHandle<unsigned char>  lockedF =
+				vcg::tri::Allocator<CMeshO>::  GetPerFaceAttribute<unsigned char> (mm->cm,"ocme_locked");
+
+		for(CMeshO::VertexIterator vi = mm->cm.vert.begin(); vi != mm->cm.vert.end(); ++vi )
+				if(!(*vi).IsD())
+						if(!lockedV[*vi]) (*vi).SetS();
+
+		for(CMeshO::FaceIterator fi = mm->cm.face.begin(); fi != mm->cm.face.end(); ++fi )
+				if(!(*fi).IsD()){
+						bool ed = !lockedF[*fi];
+						for(unsigned int i = 0; i < (*fi).VN() ; ++i)
+								 ed = ed &&  !lockedV[(*fi).V(i)];
+						if(ed) (*fi).SetS();
+						}
+}
 
 void OcmeEditPlugin::edit(){
 
@@ -513,29 +567,29 @@ void OcmeEditPlugin::edit(){
 	cells_to_edit.clear();
 
 	vcg::tri::UpdateNormals<CMeshO>::PerVertexPerFace ( mm->cm );
-
-	CMeshO::  PerFaceAttributeHandle<GIndex>  gposf =
-			vcg::tri::Allocator<CMeshO>::  GetPerFaceAttribute<GIndex> (mm->cm,"ocme_gindex");
-
-	CMeshO::  PerVertexAttributeHandle<unsigned char>  lockedV =
-			vcg::tri::Allocator<CMeshO>::  GetPerVertexAttribute<unsigned char> (mm->cm,"ocme_locked");
-
-	CMeshO::  PerFaceAttributeHandle<unsigned char>  lockedF =
-			vcg::tri::Allocator<CMeshO>::  GetPerFaceAttribute<unsigned char> (mm->cm,"ocme_locked");
-
-
-	for(unsigned int i = 0; i < mm->cm.face.size();++i)
-			if(!mm->cm.face[i].IsD())
-					if( lockedF[i] ) {
-			for(unsigned int fi = 0; fi < 3; ++ fi ){
-								lockedV[mm->cm.face[i].V(fi)] = 1;
-								mm->cm.face[i].V(fi)->SetS();
-		}
-			mm->cm.face[i].SetS();
-	}
-
-	for(unsigned int i = 0; i < mm->cm.vert.size();++i)
-			if( lockedV[i] ) mm->cm.vert[i].SetS();
+//
+//	CMeshO::  PerFaceAttributeHandle<GIndex>  gposf =
+//			vcg::tri::Allocator<CMeshO>::  GetPerFaceAttribute<GIndex> (mm->cm,"ocme_gindex");
+//
+//	CMeshO::  PerVertexAttributeHandle<unsigned char>  lockedV =
+//			vcg::tri::Allocator<CMeshO>::  GetPerVertexAttribute<unsigned char> (mm->cm,"ocme_locked");
+//
+//	CMeshO::  PerFaceAttributeHandle<unsigned char>  lockedF =
+//			vcg::tri::Allocator<CMeshO>::  GetPerFaceAttribute<unsigned char> (mm->cm,"ocme_locked");
+//
+//
+//	for(unsigned int i = 0; i < mm->cm.face.size();++i)
+//			if(!mm->cm.face[i].IsD())
+//					if( lockedF[i] ) {
+//			for(unsigned int fi = 0; fi < 3; ++ fi ){
+//								lockedV[mm->cm.face[i].V(fi)] = 1;
+//								mm->cm.face[i].V(fi)->SetS();
+//		}
+//			mm->cm.face[i].SetS();
+//	}
+//
+//	for(unsigned int i = 0; i < mm->cm.vert.size();++i)
+//			if( lockedV[i] ) mm->cm.vert[i].SetS();
 
 
 
diff --git a/src/meshlabplugins/edit_ocme/edit_ocme.h b/src/meshlabplugins/edit_ocme/edit_ocme.h
index b4c8ceec1..1e13377c3 100755
--- a/src/meshlabplugins/edit_ocme/edit_ocme.h
+++ b/src/meshlabplugins/edit_ocme/edit_ocme.h
@@ -48,6 +48,7 @@ public:
 
 	virtual bool StartEdit(MeshModel &/*m*/, GLArea * /*parent*/);
 	virtual void EndEdit(MeshModel &/*m*/, GLArea * /*parent*/);
+
 	virtual void Decorate(MeshModel &/*m*/, GLArea * /*parent*/);
 	virtual void mousePressEvent(QMouseEvent *, MeshModel &, GLArea * ) ;
 	virtual void mouseMoveEvent(QMouseEvent *, MeshModel &, GLArea * ) ;
@@ -99,11 +100,14 @@ public:
 	vcg::Trackball curr_track;
 
 void 	suspendEditMode();
+void DrawCellsToEdit();
 public slots:
 	void loadOcm();				// load an ocm database
 	void closeOcm();			// close an ocm database
 	void createOcm();			// create an ocm database
 	void edit();					// edit current selection
+	void markEditable();  // mark as selected (flag S) the editable element on the editing mesh
+	void drop();					// drop current selection
 	void commit();				// commit
 	void add();						// add new mesh
 	void addFromDisk();		// add from disk
diff --git a/src/meshlabplugins/edit_ocme/ocme.ui b/src/meshlabplugins/edit_ocme/ocme.ui
index dd74d6baf..555ab9625 100755
--- a/src/meshlabplugins/edit_ocme/ocme.ui
+++ b/src/meshlabplugins/edit_ocme/ocme.ui
@@ -10,7 +10,7 @@
     <x>0</x>
     <y>0</y>
     <width>400</width>
-    <height>398</height>
+    <height>431</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -173,7 +173,7 @@
     <property name="geometry">
      <rect>
       <x>250</x>
-      <y>340</y>
+      <y>380</y>
       <width>131</width>
       <height>27</height>
      </rect>
@@ -186,7 +186,7 @@
     <property name="geometry">
      <rect>
       <x>150</x>
-      <y>340</y>
+      <y>380</y>
       <width>93</width>
       <height>27</height>
      </rect>
@@ -199,7 +199,7 @@
     <property name="geometry">
      <rect>
       <x>0</x>
-      <y>340</y>
+      <y>380</y>
       <width>151</width>
       <height>27</height>
      </rect>
@@ -214,7 +214,7 @@
       <x>190</x>
       <y>220</y>
       <width>160</width>
-      <height>61</height>
+      <height>128</height>
      </rect>
     </property>
     <layout class="QVBoxLayout" name="verticalLayout">
@@ -225,10 +225,24 @@
        </property>
       </widget>
      </item>
+     <item>
+      <widget class="QPushButton" name="dropSelectionPushButton">
+       <property name="text">
+        <string>Drop ROI</string>
+       </property>
+      </widget>
+     </item>
      <item>
       <widget class="QPushButton" name="editPushButton">
        <property name="text">
-        <string>Edit Selected</string>
+        <string>Edit ROI</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="markEditablePushButton">
+       <property name="text">
+        <string>Select Editable</string>
        </property>
       </widget>
      </item>
diff --git a/src/meshlabplugins/edit_ocme/src/ocme/ocme.cpp b/src/meshlabplugins/edit_ocme/src/ocme/ocme.cpp
index b8f1c693c..8f5ab0ca0 100755
--- a/src/meshlabplugins/edit_ocme/src/ocme/ocme.cpp
+++ b/src/meshlabplugins/edit_ocme/src/ocme/ocme.cpp
@@ -177,6 +177,9 @@ void OCME::MarkTouchedAdded(const CellKey & key ){
 		added_cells.push_back(key);
 }
 
+void OCME::DropEdited(  ){
+		++generic_bool; // mark cells taken for editing
+}
 int OCME::ComputeLevel(const float & l){
 	return   (int)( std::log(((float)this->params.side_factor) *  float(l)   ) / log(2.f)); 
 }
diff --git a/src/meshlabplugins/edit_ocme/src/ocme/ocme_definition.h b/src/meshlabplugins/edit_ocme/src/ocme/ocme_definition.h
index bcf354932..99b54cae9 100755
--- a/src/meshlabplugins/edit_ocme/src/ocme/ocme_definition.h
+++ b/src/meshlabplugins/edit_ocme/src/ocme/ocme_definition.h
@@ -465,6 +465,8 @@ struct OCME{
 	template <class MeshType>
 	void Edit(  std::vector<Cell*> & cells, MeshType & m,  AttributeMapper attr_map = AttributeMapper());
 
+	// Undo edit
+	void 	DropEdited();
 
 	// find the removed elements
 	template <class MeshType>
diff --git a/src/meshlabplugins/edit_ocme/src/ocme/ocme_extract.h b/src/meshlabplugins/edit_ocme/src/ocme/ocme_extract.h
index 7e4f5a861..f26f2a9f8 100755
--- a/src/meshlabplugins/edit_ocme/src/ocme/ocme_extract.h
+++ b/src/meshlabplugins/edit_ocme/src/ocme/ocme_extract.h
@@ -332,6 +332,7 @@ void OCME::Extract(   std::vector<Cell*> & sel_cells, MeshType & m, AttributeMap
 	}
 }
 
+
 template <class MeshType>
 void OCME::Edit(   std::vector<Cell*> & sel_cells, MeshType & m, AttributeMapper attrMap){
 	std::vector<Cell*>     dep_cells,to_add;
diff --git a/src/meshlabplugins/edit_ocme/src/ocme/ocme_render.cpp b/src/meshlabplugins/edit_ocme/src/ocme/ocme_render.cpp
index 829e17b85..de17fddf3 100755
--- a/src/meshlabplugins/edit_ocme/src/ocme/ocme_render.cpp
+++ b/src/meshlabplugins/edit_ocme/src/ocme/ocme_render.cpp
@@ -24,9 +24,14 @@ void DrawCellSel ( CellKey & ck, int mode = 0 )
 	ubox.min=vcg::Point3f ( -0.5,-0.5,-0.5 );
 	ubox.max=-ubox.min;
 
+
 	vcg::Color4b c;
-	c = c.Scatter ( 32,lev+16 );
-	glColor ( c );
+	if(mode=3)
+			c = vcg::Color4b(230,0,0,127);
+	else{
+					c = c.Scatter ( 32,lev+16 );
+			}
+	glColor( c );
 
 	glPushMatrix();
 
@@ -36,9 +41,10 @@ void DrawCellSel ( CellKey & ck, int mode = 0 )
 			glScalef ( stepf*0.1 ,stepf*0.1  ,stepf*0.1 );
 			vcg::glBoxFlat ( ubox );
 			break;
-		case 1:	glTranslatef ( ( p[0]+ 0.5 ) *stepf, ( p[1]+ 0.5 ) *stepf, ( p[2]+ 0.5 ) *stepf );
+		case 1:;
+		case 3: glTranslatef ( ( p[0]+ 0.5 ) *stepf, ( p[1]+ 0.5 ) *stepf, ( p[2]+ 0.5 ) *stepf );
 			glScalef ( stepf ,stepf ,stepf );
-			vcg::glBoxWire ( ubox );
+			vcg::glBoxFlat ( ubox );
 			break;
 		case 2:	glTranslatef ( ( p[0]+ 0.5 ) *stepf, ( p[1]+ 0.5 ) *stepf, ( p[2]+ 0.5 ) *stepf );
 			glScalef ( stepf*0.1 ,stepf*0.1  ,stepf*0.1 );