diff --git a/vcg/complex/trimesh/edge_support.h b/vcg/complex/trimesh/edge_support.h
index 7c4df3ff..37f3f512 100644
--- a/vcg/complex/trimesh/edge_support.h
+++ b/vcg/complex/trimesh/edge_support.h
@@ -42,11 +42,15 @@ namespace vcg
 		*/
 
 		template <class MeshType  >
-		struct EdgeSupport{
+		class EdgeSupport{
+		public:
 			typedef typename MeshType::VertexType VertexType;
 			typedef typename MeshType::VertexPointer VertexPointer;
 			typedef typename MeshType::EdgePointer EdgePointer;
-			typedef typename  MeshType::FaceIterator FaceIterator;
+			typedef typename MeshType::EdgeType EdgeType;
+			typedef typename MeshType::EdgeIterator EdgeIterator;
+			typedef typename MeshType::FaceIterator FaceIterator;
+			typedef typename MeshType::FaceType FaceType;
 
 			struct VertexPairEdgePtr{
 				VertexPairEdgePtr(VertexPointer _v0,VertexPointer _v1,EdgePointer _ep):v0(_v0),v1(_v1),ep(_ep){if(v0>v1) std::swap(v0,v1);}
@@ -70,7 +74,7 @@ namespace vcg
 				FaceIterator fi;
 				int n_edges = 0;
 				for(fi = m.face.begin(); fi != m.face.end(); ++fi) if(! (*fi).IsD()) n_edges+=(*fi).VN();		
-				MeshType::EdgeIterator ei = vcg::tri::Allocator<MeshType>::AddEdges(m,n_edges);
+				typename MeshType::EdgeIterator ei = vcg::tri::Allocator<MeshType>::AddEdges(m,n_edges);
 				
 				std::vector<VertexPairEdgePtr> all;
 				int firstEdge = 0;
@@ -82,8 +86,12 @@ namespace vcg
 						(*ei).HENp()	= &m.edge[firstEdge + (i +1) % (*fi).VN()];
 						if(MeshType::EdgeType::HasEFAdjacency()) 
 							(*ei).EFp() = &(*fi);
+						if( MeshType::FaceType::HasFHEAdjacency())
+							(*fi).FHEp() = &(*ei);
 						if(MeshType::EdgeType::HasHEPrevAdjacency())
 							(*ei).HEPp()	= &m.edge[firstEdge + (i +(*fi).VN()-1) % (*fi).VN()];
+						if(HasVEAdjacency(m))
+							(*ei).HEVp()->VEp() = &(*ei);
 						all.push_back(VertexPairEdgePtr((*fi).V(i), (*fi).V((*fi).Next(i)),&(*ei)));// it will be used to link the hedges
 					}
 					firstEdge += (*fi).VN();
@@ -115,10 +123,12 @@ namespace vcg
 			static void ComputeIndexedFromHalfEdge(  MeshType & m ){
 				assert(HasFVAdjacency(m));
 				assert(MeshType::EdgeType::HasHENextAdjacency());
+				assert(MeshType::EdgeType::HasHEVAdjacency());
 				assert(MeshType::EdgeType::HasHEOppAdjacency());			
-				bool createFace,hasHEF;
+				assert(MeshType::FaceType::HasFHEAdjacency());
+				bool createFace,hasHEF,hasFHE;
 
-				typename MeshType::PerEdgeAttributeHandle<bool> hV = Allocator<MeshType>::AddPerEdgeAttribute<bool>(m,"");
+				typename MeshType::template PerEdgeAttributeHandle<bool> hV = Allocator<MeshType>::template AddPerEdgeAttribute<bool>(m,"");
 
 				typename MeshType::EdgeIterator ei;
 				typename MeshType::FacePointer fp;
@@ -126,14 +136,15 @@ namespace vcg
 				typename MeshType::EdgePointer ep,epF;
 				int vi = 0;
 
-				hasHEF = (typename MeshType::EdgeType::HasEFAdjacency());
+				hasHEF = (MeshType::EdgeType::HasEFAdjacency());
 				assert( !hasHEF || (hasHEF && m.fn>0));
 
 				// if the edgetype has the pointer to face   
 				// it is assumed the the edget2face pointer (HEFp) are correct
 				// and the faces are allocated
 					for ( ei = m.edge.begin(); ei != m.edge.end(); ++ei)
- 					if(!hV[(*ei)] )// has not be visited yet
+						if(!(*ei).IsD())
+  					if(!hV[(*ei)] )// has not be visited yet
 					{
 						if(!hasHEF)// if it has 
 							fp = &(* Allocator<MeshType>::AddFaces(m,1));
@@ -141,17 +152,247 @@ namespace vcg
 							fp = (*ei).EFp();
 
 						ep = epF = &(*ei);
-						ep = ep->HENp();
 						std::vector<VertexPointer> vpts;
-						while(ep!=epF){vpts.push_back((*ep).HEVp()); ep=ep->HENp();}
-						fp ->Alloc(vpts.size());
+						do{vpts.push_back((*ep).HEVp()); ep=ep->HENp();}while(ep!=epF);
+						int idbg  =fp->VN();
+						if(fp->VN() != vpts.size()){
+							fp->Dealloc();
+							fp ->Alloc(vpts.size());
+						}
+						int idbg1  =fp->VN();
 						for(int i  = 0; i < vpts.size();++i) fp ->V(i) = vpts[i];// set the pointer from face to vertex
 
- 					hV[(*ei)] = true;
+  					hV[(*ei)] = true;
 				}
 				Allocator<MeshType>::DeletePerEdgeAttribute(m,hV);
 			}
-	};
+
+	/**
+	Checks pointers FHEp() are valid
+	**/
+	static bool CheckConsistency_FHEp(MeshType &  m){
+		assert(MeshType::FaceType::HasFHEAdjacency());
+		FaceIterator fi;
+		for(fi = m.face.begin(); fi != m.face.end(); ++fi)
+			if(!(*fi).IsD()){
+				if((*fi).FHEp() <  &(*m.edge.begin())) return false;
+				if((*fi).FHEp() >  &(m.edge.back())) return false;
+			}
+		return true;
+	}
+
+	/**
+	Checks that half edges and face relation are consistent
+	**/
+	static bool CheckConsistency(MeshType & m){
+		assert(MeshType::EdgeType::HasHENextAdjacency());
+		assert(MeshType::EdgeType::HasHEOppAdjacency());			
+		assert(MeshType::EdgeType::HasHEVAdjacency());
+		assert(MeshType::FaceType::HasFHEAdjacency());
+
+		bool hasHEF = ( MeshType::EdgeType::HasEFAdjacency());
+		bool hasHEP = ( MeshType::EdgeType::HasHEPrevAdjacency());
+
+		FaceIterator fi;
+		EdgePointer ep,ep1;
+		int cnt = 0;
+		if(( MeshType::EdgeType::HasEFAdjacency())){
+			int iDb = 0;
+			for(fi = m.face.begin(); fi != m.face.end(); ++fi,++iDb)
+				if(!(*fi).IsD())
+				{
+					ep = ep1 = (*fi).FHEp();
+					do{
+						if(ep->IsD()) 
+							return false; // the edge should not be connected, it has been deleted
+	 					if(ep->EFp() != &(*fi)) 
+							return false;// edge is not pointing to the rigth face
+						ep = ep->HENp();
+						if(cnt++ > m.en)
+							return false; // edges are ill connected (HENp())
+					}while(ep!=ep1);
+				}
+		}
+
+		EdgePointer epPrev;
+		EdgeIterator ei;
+		bool extEdge ;
+		for( ei  = m.edge.begin(); ei != m.edge.end(); ++ei)
+			if(!(*ei).IsD())
+		{
+			cnt = 0;
+			epPrev = ep = ep1 = &(*ei);
+			do{
+				extEdge = (ep->EFp()==NULL);
+				if(hasHEP){
+					if( ep->HENp()->HEPp() != ep) 
+						return false; // next and prev relation are not mutual
+					if( ep->HEPp() == ep) 
+						return false; // the previous of an edge cannot be the edge itself
+				}
+				if( ep->HEOp()  == ep) 
+					return false; // opposite relation is not mutual
+				if( ep->HEOp()->HEOp() != ep) 
+					return false; // opposite relation is not mutual
+				if(ep->HENp() == ep)
+					return false; //  the next of an edge cannot be the edge itself
+				ep = ep->HENp();
+				if( ep->HEVp() != epPrev->HEOp()->HEVp()) 
+					return false; // the opposite edge points to a vertex different that the vertex of the next edge
+				epPrev = ep;
+				if(cnt++ > m.en) 
+					return false; // edges are ill connected (HENp())
+			}while(ep!=ep1);
+		}
+
+	return true;
+	}
+
+	/** Set the relations HEFp(), FHEp() from a loop of edges to a face
+	*/
+	private:
+	static void SetRelationsLoopFace(EdgeType * e0, FaceType * f){
+		assert(EdgeType::HasHENextAdjacency());
+		assert(FaceType::HasFHEAdjacency());
+
+		EdgeType *e = e0;
+		assert(e!=NULL);
+		do{ e->EFp() = f; e = e->HENp(); } while(e != e0);
+		f->FHEp() = e0;
+	}
+
+	/**
+	Merge the two faces. This will probably become a class template or a functor
+	*/
+	static void MergeFaces(FaceType *, FaceType *){};
+
+	/**
+	Find previous hedge in the loop
+	*/
+	static EdgeType *  PreviousEdge(EdgeType * e0){
+		EdgeType *  ep = e0;
+		do{
+			if(ep->HENp() == e0) return ep;
+				ep = ep->HENp();
+			}while(ep!=e0);
+	}
+
+	public:
+	/** Adds an edge between the sources of e0 and e1 and set all the topology relations.
+	If the edges store the pointers to the faces then a new face is created.
+    <--- e1 ---- X <------e1_HEPp---
+                 ^ 	
+                 ||
+             ei0 || ei1     
+                 ||
+                  v
+	 ----e0_HEPp-> X ----- e0 ------>
+	*/
+	static void AddEdge(MeshType &m, EdgeType * e0, EdgeType * e1){
+		EdgeType *iii =e0->HENp();
+		assert(e1!=e0->HENp());
+		assert(e0!=e1->HENp());
+		EdgePointer tmp;
+		bool hasP =  MeshType::EdgeType::HasHEPrevAdjacency();
+		assert(e0->HEOp() != e1); // the hedge already exists
+		assert(e0!=e1->HENp());
+
+		std::vector<typename MeshType::EdgePointer* > toUpdate;
+		toUpdate.push_back(&e0);
+		toUpdate.push_back(&e1);
+		EdgeIterator ei0  = vcg::tri::Allocator<MeshType>::AddEdges(m,2,toUpdate);
+
+		EdgeIterator ei1 = ei0; ++ei1;
+		(*ei0).HENp() = e1;(*ei0).HEVp() = e0->HEVp();
+		(*ei1).HENp() = e0;(*ei1).HEVp() = e1->HEVp();
+
+		EdgePointer e0_HEPp = 0,e1_HEPp = 0,ep =0;
+		if(hasP){
+			e0_HEPp = e0->HEPp();
+			e1_HEPp = e1->HEPp();
+		}else{// does not have pointer to previous, it must be computed
+			ep = e0;
+			do{
+				if(ep->HENp() == e0) e0_HEPp = ep;
+				if(ep->HENp() == e1) e1_HEPp = ep;
+				ep = ep->HENp();
+			}while(ep!=e0);
+		}
+		if(hasP){
+			(*ei0).HEPp() = e0->HEPp();
+			(*ei1).HEPp() = e1->HEPp();
+			e0->HEPp() = &(*ei1);
+			e1->HEPp() = &(*ei0);
+		}
+		e0_HEPp -> HENp() = &(*ei0);
+		e1_HEPp -> HENp() = &(*ei1);
+
+		(*ei0).HEOp() = &(*ei1);
+		(*ei1).HEOp() = &(*ei0);
+
+
+		if( EdgeType::HasEFAdjacency() && FaceType::HasFHEAdjacency()){
+			FaceIterator fi0  = vcg::tri::Allocator<MeshType>::AddFaces(m,1);
+			m.face.back().ImportLocal(*e0->EFp());
+
+			SetRelationsLoopFace(&(*ei0),e1->EFp());		// one loop to the old face
+			SetRelationsLoopFace(&(*ei1),&m.face.back());	// the other  to the new face
+		}
+	}
+
+	/** Detach the topology relations of a given edge
+    <--- e->HENPp -X --- <---------eO_HEPp---
+                   ^ 	
+                   ||
+               e   || e->HEOp()     
+                   ||
+                    v
+	 ----e_HEPp--> X ----- e->HEOp->HENPp() ------>
+	 
+	*/
+	static void RemoveEdge(MeshType &m, EdgeType * e){
+		assert(MeshType::EdgeType::HasHENextAdjacency());
+		assert(MeshType::EdgeType::HasHEOppAdjacency());			
+		assert(MeshType::FaceType::HasFHEAdjacency());
+
+		bool hasP =  MeshType::EdgeType::HasHEPrevAdjacency();
+		EdgePointer e_HEPp,eO_HEPp;
+
+		if(hasP){
+			e_HEPp = e->HEPp();
+			eO_HEPp = e->HEOp()->HEPp();
+		}else{
+			e_HEPp = PreviousEdge(e);
+			eO_HEPp = PreviousEdge(e->HEOp());
+		}
+
+		assert(e_HEPp->HENp() == e);
+		assert(eO_HEPp->HENp() == e->HEOp());
+		e_HEPp->HENp() = e->HEOp()->HENp();
+		eO_HEPp->HENp() = e-> HENp();
+
+		if(hasP) {
+			e->HEOp()->HENp()->HEPp() = e_HEPp;
+			e->HENp()->HEPp() = eO_HEPp;
+
+			e->HEPp() = NULL;
+			e-> HEOp()->HEPp() = NULL;
+		}
+
+
+		// take care of the faces
+		if(MeshType::EdgeType::HasEFAdjacency()){
+			MergeFaces(e_HEPp->EFp(),eO_HEPp->EFp());
+			vcg::tri::Allocator<MeshType>::DeleteFace(m,*eO_HEPp->EFp());
+			SetRelationsLoopFace(e_HEPp,e_HEPp->EFp());
+
+		}
+		 vcg::tri::Allocator<MeshType>::DeleteEdge(m,*e->HEOp());
+		 vcg::tri::Allocator<MeshType>::DeleteEdge(m,*e);
+
+	}
+
+	};// end class EdgeSupport 
 } // end namespace vcg
 }
 #endif // __VCGLIB_EDGE_SUPPORT