BambuStudio/libigl/igl/copyleft/cgal/complex_to_mesh.cpp

153 lines
6.2 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2014 Alec Jacobson <alecjacobson@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla Public License
// v. 2.0. If a copy of the MPL was not distributed with this file, You can
// obtain one at http://mozilla.org/MPL/2.0/.
#include "complex_to_mesh.h"
#include "../../centroid.h"
#include "../../remove_unreferenced.h"
#include <CGAL/Surface_mesh_default_triangulation_3.h>
#include <CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h>
#include <set>
#include <stack>
template <typename Tr, typename DerivedV, typename DerivedF>
IGL_INLINE bool igl::copyleft::cgal::complex_to_mesh(
const CGAL::Complex_2_in_triangulation_3<Tr> & c2t3,
Eigen::PlainObjectBase<DerivedV> & V,
Eigen::PlainObjectBase<DerivedF> & F)
{
using namespace Eigen;
// CGAL/IO/Complex_2_in_triangulation_3_file_writer.h
using CGAL::Surface_mesher::number_of_facets_on_surface;
typedef typename CGAL::Complex_2_in_triangulation_3<Tr> C2t3;
typedef typename Tr::Finite_facets_iterator Finite_facets_iterator;
typedef typename Tr::Finite_vertices_iterator Finite_vertices_iterator;
typedef typename Tr::Facet Facet;
typedef typename Tr::Edge Edge;
typedef typename Tr::Vertex_handle Vertex_handle;
// Header.
const Tr& tr = c2t3.triangulation();
bool success = true;
const int n = tr.number_of_vertices();
const int m = c2t3.number_of_facets();
assert(m == number_of_facets_on_surface(tr));
// Finite vertices coordinates.
std::map<Vertex_handle, int> v2i;
V.resize(n,3);
{
int v = 0;
for(Finite_vertices_iterator vit = tr.finite_vertices_begin();
vit != tr.finite_vertices_end();
++vit)
{
V(v,0) = vit->point().x();
V(v,1) = vit->point().y();
V(v,2) = vit->point().z();
v2i[vit] = v++;
}
}
{
Finite_facets_iterator fit = tr.finite_facets_begin();
std::set<Facet> oriented_set;
std::stack<Facet> stack;
while ((int)oriented_set.size() != m)
{
while ( fit->first->is_facet_on_surface(fit->second) == false ||
oriented_set.find(*fit) != oriented_set.end() ||
oriented_set.find(c2t3.opposite_facet(*fit)) !=
oriented_set.end() )
{
++fit;
}
oriented_set.insert(*fit);
stack.push(*fit);
while(! stack.empty() )
{
Facet f = stack.top();
stack.pop();
for(int ih = 0 ; ih < 3 ; ++ih)
{
const int i1 = tr.vertex_triple_index(f.second, tr. cw(ih));
const int i2 = tr.vertex_triple_index(f.second, tr.ccw(ih));
const typename C2t3::Face_status face_status
= c2t3.face_status(Edge(f.first, i1, i2));
if(face_status == C2t3::REGULAR)
{
Facet fn = c2t3.neighbor(f, ih);
if (oriented_set.find(fn) == oriented_set.end())
{
if(oriented_set.find(c2t3.opposite_facet(fn)) == oriented_set.end())
{
oriented_set.insert(fn);
stack.push(fn);
}else {
success = false; // non-orientable
}
}
}else if(face_status != C2t3::BOUNDARY)
{
success = false; // non manifold, thus non-orientable
}
} // end "for each neighbor of f"
} // end "stack non empty"
} // end "oriented_set not full"
F.resize(m,3);
int f = 0;
for(typename std::set<Facet>::const_iterator fit =
oriented_set.begin();
fit != oriented_set.end();
++fit)
{
const typename Tr::Cell_handle cell = fit->first;
const int& index = fit->second;
const int index1 = v2i[cell->vertex(tr.vertex_triple_index(index, 0))];
const int index2 = v2i[cell->vertex(tr.vertex_triple_index(index, 1))];
const int index3 = v2i[cell->vertex(tr.vertex_triple_index(index, 2))];
// This order is flipped
F(f,0) = index1;
F(f,1) = index2;
F(f,2) = index3;
f++;
}
assert(f == m);
} // end if(facets must be oriented)
// This CGAL code seems to randomly assign the global orientation
// Flip based on the signed volume.
Eigen::Vector3d cen;
double vol;
igl::centroid(V,F,cen,vol);
if(vol < 0)
{
// Flip
F = F.rowwise().reverse().eval();
}
// CGAL code somehow can end up with unreferenced vertices
{
VectorXi _1;
remove_unreferenced( MatrixXd(V), MatrixXi(F), V,F,_1);
}
return success;
}
#ifdef IGL_STATIC_LIBRARY
template bool igl::copyleft::cgal::complex_to_mesh<CGAL::Delaunay_triangulation_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_data_structure_3<CGAL::Surface_mesh_vertex_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_vertex_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_ds_vertex_base_3<void> > >, CGAL::Delaunay_triangulation_cell_base_with_circumcenter_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Surface_mesh_cell_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_cell_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_ds_cell_base_3<void> > > >, CGAL::Sequential_tag>, CGAL::Default, CGAL::Default>, Eigen::Matrix<double, -1, -1, 0, -1, -1>, Eigen::Matrix<int, -1, -1, 0, -1, -1> >(CGAL::Complex_2_in_triangulation_3<CGAL::Delaunay_triangulation_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_data_structure_3<CGAL::Surface_mesh_vertex_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_vertex_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_ds_vertex_base_3<void> > >, CGAL::Delaunay_triangulation_cell_base_with_circumcenter_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Surface_mesh_cell_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_cell_base_3<CGAL::Robust_circumcenter_traits_3<CGAL::Epick>, CGAL::Triangulation_ds_cell_base_3<void> > > >, CGAL::Sequential_tag>, CGAL::Default, CGAL::Default>, void> const&, Eigen::PlainObjectBase<Eigen::Matrix<double, -1, -1, 0, -1, -1> >&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> >&);
#endif