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Rewrite of Extract_triangles_and_link() using no map

This commit is contained in:
Andreas Fabri 2014-04-10 10:11:33 +02:00
parent e986d53df6
commit bcb7cc0332
2 changed files with 49 additions and 97 deletions
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6
Surface_mesh_simplification/include/CGAL/Surface_mesh_simplification/Policies/Edge_collapse/Edge_profile.h
View File

@ -149,12 +149,6 @@ private:
void Extract_borders() ;
void Extract_triangle( vertex_descriptor const& v0
, vertex_descriptor const& v1
, vertex_descriptor const& v2
, edge_descriptor const& e02
) ;
void Extract_triangles_and_link() ;
private:

132
Surface_mesh_simplification/include/CGAL/Surface_mesh_simplification/Policies/Edge_collapse/Edge_profile_impl.h
View File

@ -125,106 +125,64 @@ void Edge_profile<ECM>::Extract_borders()
}
}
//
// If (v0,v1,v2) is a finite triangular facet of the mesh, that is, NONE of these vertices are boundary vertices,
// the triangle, properly oriented, is added to mTriangles.
//
template<class ECM>
void Edge_profile<ECM>::Extract_triangle( vertex_descriptor const& v0
, vertex_descriptor const& v1
, vertex_descriptor const& v2
, edge_descriptor const& e02
)
{
// The 3 vertices are obtained by circulating ccw around v0, that is, e02 = next_ccw(e01).
// Since these vertices are NOT obtained by circulating the face, the actual triangle orientation is unspecified.
// The triangle is oriented v0->v2->v1 if the next edge that follows e02 (which is the edge v0->v2) is v2->v1.
if ( target(next_edge(e02,surface_mesh()),surface_mesh()) == v1 )
{
// The triangle is oriented v0->v2->v1.
// In this case e02 is an edge of the facet.
// If this facet edge is a border edge then this triangle is not in the mesh .
if ( ! e02->is_border() )
mTriangles.push_back(Triangle(v0,v2,v1) ) ;
}
else
{
// The triangle is oriented v0->v1->v2.
// In this case, e20 and not e02, is an edge of the facet.
// If this facet edge is a border edge then this triangle is not in the mesh .
if ( ! opposite_edge(e02,surface_mesh())->is_border() )
mTriangles.push_back(Triangle(v0,v1,v2) ) ;
}
}
//
// Extract all triangles (its normals) and vertices (the link) around the collapsing edge p_q
//
template<class ECM>
void Edge_profile<ECM>::Extract_triangles_and_link()
{
std::set<vertex_descriptor> lCollected ;
//
// Extract around mV0, CCW
//
vertex_descriptor v0 = mV0;
vertex_descriptor v1 = mV1;
edge_descriptor e02 = mV0V1;
do
{
e02 = opposite_edge(prev_edge(e02,surface_mesh()), surface_mesh());
vertex_descriptor v2 = target(e02,surface_mesh());
if ( v2 != mV1 )
{
// look at the two faces or holes adjacent to edge (v0,v1)
// and at the opposite vertex if it exists
edge_descriptor endleft, endright;
if(vL() != vertex_descriptor()){
mLink.push_back(vL());
mTriangles.push_back(Triangle(v0(),v1(),vL()) ) ;
endright = next_edge(v0_v1(), surface_mesh());
}
if(vR() != vertex_descriptor()){
mLink.push_back(vR());
mTriangles.push_back(Triangle(v1(),v0(),vR()) ) ;
endleft = next_edge(v1_v0(), surface_mesh());
}
// counterclockwise around v0
edge_descriptor e02 = opposite_edge(prev_edge(v0_v1(),surface_mesh()), surface_mesh());
vertex_descriptor v, v2 =target(e02,surface_mesh());
while(e02 != endleft) {
if(v2 != vL()){
mLink.push_back(v2);
CGAL_assertion_code( bool lInserted = )
lCollected.insert(v2)
CGAL_assertion_code( .second ) ;
CGAL_assertion(lInserted);
}
Extract_triangle(v0,v1,v2,e02);
v1 = v2 ;
}
while ( e02 != mV0V1 ) ;
//
// Extract around mV1, CCW
//
v0 = mV1;
e02 = opposite_edge(prev_edge(mV1V0,surface_mesh()), surface_mesh());
v1 = target(e02,surface_mesh());
// This could have been added to the link while circulating around mP
if ( v1 != mV0 && lCollected.find(v1) == lCollected.end() )
mLink.push_back(v1) ;
bool is_border = e02->is_border();
e02 = opposite_edge(prev_edge(e02,surface_mesh()), surface_mesh());
v = target(e02,surface_mesh());
if(! is_border){
mTriangles.push_back(Triangle(v,v0(),v2) ) ;
}
v2 = v;
}
if(v != vR()){
mLink.push_back(v);
}
do
{
vertex_descriptor v2 = target(e02,surface_mesh());
// Any of the vertices found around mP can be reached again around mQ, but we can't duplicate them here.
if ( v2 != mV0 && lCollected.find(v2) == lCollected.end() )
// vounterclockwise around v1
e02 = opposite_edge(prev_edge(v1_v0(),surface_mesh()), surface_mesh());
v2 =target(e02,surface_mesh());
while(e02 != endright) {
if(v2 != vR()){
mLink.push_back(v2);
Extract_triangle(v0,v1,v2,e02);
v1 = v2 ;
e02 = opposite_edge(prev_edge(e02,surface_mesh()), surface_mesh());
}
while ( e02 != mV1V0 ) ;
bool is_border = e02->is_border();
e02 = opposite_edge(prev_edge(e02,surface_mesh()), surface_mesh());
v = target(e02,surface_mesh());
if(! is_border){
mTriangles.push_back(Triangle(v,v1(),v2) ) ;
}
v2 = v;
}
if(v != vL()){
mLink.push_back(v);
}
}
} // namespace Surface_mesh_simplification