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

74 lines
2.4 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2013 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 "face_occurrences.h"
#include "list_to_matrix.h"
#include "matrix_to_list.h"
#include <map>
#include "sort.h"
#include <cassert>
template <typename IntegerF, typename IntegerC>
IGL_INLINE void igl::face_occurrences(
const std::vector<std::vector<IntegerF> > & F,
std::vector<IntegerC> & C)
{
using namespace std;
// Get a list of sorted faces
vector<vector<IntegerF> > sortedF = F;
for(int i = 0; i < (int)F.size();i++)
{
sort(sortedF[i].begin(),sortedF[i].end());
}
// Count how many times each sorted face occurs
map<vector<IntegerF>,int> counts;
for(int i = 0; i < (int)sortedF.size();i++)
{
if(counts.find(sortedF[i]) == counts.end())
{
// initialize to count of 1
counts[sortedF[i]] = 1;
}else
{
// increment count
counts[sortedF[i]]++;
assert(counts[sortedF[i]] == 2 && "Input should be manifold");
}
}
// Resize output to fit number of ones
C.resize(F.size());
for(int i = 0;i< (int)F.size();i++)
{
// sorted face should definitely be in counts map
assert(counts.find(sortedF[i]) != counts.end());
C[i] = counts[sortedF[i]];
}
}
template <typename DerivedF, typename DerivedC>
IGL_INLINE void igl::face_occurrences(
const Eigen::MatrixBase<DerivedF> & F,
Eigen::PlainObjectBase<DerivedC> & C)
{
// Should really just rewrite using Eigen+libigl ...
std::vector<std::vector<typename DerivedF::Scalar> > vF;
matrix_to_list(F,vF);
std::vector<std::vector<typename DerivedC::Scalar> > vC;
igl::face_occurrences(vF,vC);
list_to_matrix(vC,C);
}
#ifdef IGL_STATIC_LIBRARY
// Explicit template instantiation
// generated by autoexplicit.sh
template void igl::face_occurrences<unsigned int, int>(std::vector<std::vector<unsigned int, std::allocator<unsigned int> >, std::allocator<std::vector<unsigned int, std::allocator<unsigned int> > > > const&, std::vector<int, std::allocator<int> >&);
template void igl::face_occurrences<int, int>(std::vector<std::vector<int, std::allocator<int> >, std::allocator<std::vector<int, std::allocator<int> > > > const&, std::vector<int, std::allocator<int> >&);
#endif