diff --git a/vcg/simplex/edge/topology.h b/vcg/simplex/edge/topology.h index 51ac735e..da1ebb7c 100644 --- a/vcg/simplex/edge/topology.h +++ b/vcg/simplex/edge/topology.h @@ -32,7 +32,7 @@ namespace vcg { namespace edge { /** \addtogroup edge */ /*@{*/template -inline bool IsEdgeManifold( EdgeType const & e, const int j ) +inline bool IsEdgeManifoldFF( EdgeType const & e, const int j ) { assert(e.cFFp(j) != 0); // never try to use this on uncomputed topology @@ -80,7 +80,144 @@ void VEStarVE(const typename EdgeType::VertexType* vp, std::vector & } } +/// Completely detach an edge from the VE adjacency. Useful before deleting it +template +void VEDetach(EdgeType & e) +{ + VEDetach(e,0); + VEDetach(e,1); +} + +/// It detaches the given edge e from the VE adjacency on the vertex z +/// It is used for careful hand stictching of topologies. +template +void VEDetach(EdgeType & e, int z) +{ + typename EdgeType::VertexType *vz = e.V(z); // the vertex from which the edge must be detached. + + if(vz->VEp()==&e ) //if it is the first edge in the VE chain it detaches it from the begin + { + int fz = vz->VEi(); + vz->VEp() = e.VEp(fz); + vz->VEi() = e.VEi(fz); + } + else // scan the list of edges to find the current edge e to be detached + { + VEIterator x(vz->VEp(),vz->VEi()); + VEIterator y; + + for(;;) + { + y = x; + ++x; + assert(x.e!=0); + if(x.e==&e) // found! + { + y.e->VEp(y.z) = e.VEp(z); + y.e->VEi(y.z) = e.VEi(z); + break; + } + } + } +} + +/// Append an edge in the VE list of vertex e->V(z) +template +void VEAppend(EdgeType* & e, int z) +{ + typename EdgeType::VertexType *v = e->V(z); + if (v->VEp()!=0) + { + EdgeType *e0=v->VEp(); + int z0=v->VEi(); + //append + e->VEp(z)=e0; + e->VEi(z)=z0; + } + v->VEp()=e; + v->VEi()=z; +} + + +/*! Perform a simple edge collapse using VE adjacency + * + * It collapses the two edges incidnent on the indicated vertex so that the passed edge survives, + * the indicated vertex is deleted, and the edge ajacent to e0 along z is deleted too. + * It assumes that the edge mesh is 1-Manifold. + * If the indicated vertex is boundary or non manifold the function do nothing. + * + * v0 vd v1 + * ---O-------O-------O--- + * z0 e0 z e1 z1 + * + * v0 v1 + * ---O---------------O--- + * e0 + * + * + */ +template +void VEEdgeCollapse(MeshType &poly, typename MeshType::EdgeType *e0, const int z) +{ + typedef typename MeshType::EdgeType EdgeType; + typedef typename MeshType::VertexType VertexType; + + VertexType *vd = e0->V(z); + + std::vector starVecEp; + edge::VEStarVE(vd,starVecEp); + if(starVecEp.size()!=2) return; + + EdgeType *e1=0; // this edge will be deleted + if( starVecEp[0] == e0 ) e1 = starVecEp[1]; + if( starVecEp[1] == e0 ) e1 = starVecEp[0]; + assert(e1 && (e1!=e0) ); + + int z0 = (z+1)%2; + int z1 = -1; + if(e1->V(0) == vd) z1=1; + if(e1->V(1) == vd) z1=0; + assert(z1!=-1); + + VertexType *v1 = e1->V(z1); + + edge::VEDetach(*e1); + edge::VEDetach(*e0,z); + e0->V(z) = v1; + edge::VEAppend(e0, z); + tri::Allocator::DeleteEdge(poly,*e1); + tri::Allocator::DeleteVertex(poly,*vd); +} + +template +void VEEdgeCollapse(MeshType &poly, typename MeshType::VertexType *v) +{ + VEEdgeCollapse(poly,v->VEp(),v->VEi()); +} + + + +/*! Returns the number of incident edges over a vertex vp; Using the VE adjacency. + * + * It just follows the chain of incident edges of the VE adjacency. +*/ + +template +int VEDegree(const typename EdgeType::VertexType* vp) +{ + int cnt=0; + edge::VEIterator vei(vp); + while(!vei.End()) + { + ++cnt; + ++vei; + } + return cnt; +} + + } // end namespace edge } // end namespace vcg + #endif