dust3d/third_party/libigl/include/igl/extract_manifold_patches.cpp

104 lines
5.6 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2016 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 "extract_manifold_patches.h"
#include "unique_edge_map.h"
#include <cassert>
#include <limits>
#include <queue>
template<
typename DerivedF,
typename DerivedEMAP,
typename uE2EType,
typename DerivedP>
IGL_INLINE size_t igl::extract_manifold_patches(
const Eigen::PlainObjectBase<DerivedF>& F,
const Eigen::PlainObjectBase<DerivedEMAP>& EMAP,
const std::vector<std::vector<uE2EType> >& uE2E,
Eigen::PlainObjectBase<DerivedP>& P)
{
assert(F.cols() == 3);
const size_t num_faces = F.rows();
auto edge_index_to_face_index = [&](size_t ei) { return ei % num_faces; };
auto face_and_corner_index_to_edge_index = [&](size_t fi, size_t ci) {
return ci*num_faces + fi;
};
auto is_manifold_edge = [&](size_t fi, size_t ci) -> bool {
const size_t ei = face_and_corner_index_to_edge_index(fi, ci);
return uE2E[EMAP(ei, 0)].size() == 2;
};
auto get_adj_face_index = [&](size_t fi, size_t ci) -> size_t {
const size_t ei = face_and_corner_index_to_edge_index(fi, ci);
const auto& adj_faces = uE2E[EMAP(ei, 0)];
assert(adj_faces.size() == 2);
if (adj_faces[0] == ei) {
return edge_index_to_face_index(adj_faces[1]);
} else {
assert(adj_faces[1] == ei);
return edge_index_to_face_index(adj_faces[0]);
}
};
typedef typename DerivedP::Scalar Scalar;
const Scalar INVALID = std::numeric_limits<Scalar>::max();
P.resize(num_faces,1);
P.setConstant(INVALID);
size_t num_patches = 0;
for (size_t i=0; i<num_faces; i++) {
if (P(i,0) != INVALID) continue;
std::queue<size_t> Q;
Q.push(i);
P(i,0) = num_patches;
while (!Q.empty()) {
const size_t fid = Q.front();
Q.pop();
for (size_t j=0; j<3; j++) {
if (is_manifold_edge(fid, j)) {
const size_t adj_fid = get_adj_face_index(fid, j);
if (P(adj_fid,0) == INVALID) {
Q.push(adj_fid);
P(adj_fid,0) = num_patches;
}
}
}
}
num_patches++;
}
assert((P.array() != INVALID).all());
return num_patches;
}
template<
typename DerivedF,
typename DerivedP>
IGL_INLINE size_t igl::extract_manifold_patches(
const Eigen::PlainObjectBase<DerivedF>& F,
Eigen::PlainObjectBase<DerivedP>& P)
{
Eigen::MatrixXi E, uE;
Eigen::VectorXi EMAP;
std::vector<std::vector<size_t> > uE2E;
igl::unique_edge_map(F, E, uE, EMAP, uE2E);
return igl::extract_manifold_patches(F, EMAP, uE2E, P);
}
#ifdef IGL_STATIC_LIBRARY
// Explicit template instantiation
// generated by autoexplicit.sh
template unsigned long igl::extract_manifold_patches<Eigen::Matrix<int, -1, -1, 0, -1, -1>, Eigen::Matrix<int, -1, 1, 0, -1, 1> >(Eigen::PlainObjectBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&);
template size_t igl::extract_manifold_patches<Eigen::Matrix<int, -1, -1, 0, -1, -1>, Eigen::Matrix<int, -1, 1, 0, -1, 1>, unsigned long, Eigen::Matrix<int, -1, 1, 0, -1, 1> >(Eigen::PlainObjectBase<Eigen::Matrix<int, -1, -1, 0, -1, -1> > const&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> > const&, std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&);
template unsigned long igl::extract_manifold_patches<Eigen::Matrix<int, -1, 3, 1, -1, 3>, Eigen::Matrix<int, -1, 1, 0, -1, 1>, unsigned long, Eigen::Matrix<int, -1, 1, 0, -1, 1> >(Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 3, 1, -1, 3> > const&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> > const&, std::vector<std::vector<unsigned long, std::allocator<unsigned long> >, std::allocator<std::vector<unsigned long, std::allocator<unsigned long> > > > const&, Eigen::PlainObjectBase<Eigen::Matrix<int, -1, 1, 0, -1, 1> >&);
#ifdef WIN32
template unsigned __int64 igl::extract_manifold_patches<class Eigen::Matrix<int, -1, -1, 0, -1, -1>, class Eigen::Matrix<int, -1, 1, 0, -1, 1>, unsigned __int64, class Eigen::Matrix<int, -1, 1, 0, -1, 1>>(class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, -1, 0, -1, -1>> const &, class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, 1, 0, -1, 1>> const &, class std::vector<class std::vector<unsigned __int64, class std::allocator<unsigned __int64>>, class std::allocator<class std::vector<unsigned __int64, class std::allocator<unsigned __int64>>>> const &, class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, 1, 0, -1, 1>> &);
template unsigned __int64 igl::extract_manifold_patches<class Eigen::Matrix<int, -1, 3, 1, -1, 3>, class Eigen::Matrix<int, -1, 1, 0, -1, 1>, unsigned __int64, class Eigen::Matrix<int, -1, 1, 0, -1, 1>>(class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, 3, 1, -1, 3>> const &, class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, 1, 0, -1, 1>> const &, class std::vector<class std::vector<unsigned __int64, class std::allocator<unsigned __int64>>, class std::allocator<class std::vector<unsigned __int64, class std::allocator<unsigned __int64>>>> const &, class Eigen::PlainObjectBase<class Eigen::Matrix<int, -1, 1, 0, -1, 1>> &);
#endif
#endif