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

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// 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 "intersect.h"
template <class M>
IGL_INLINE void igl::intersect(const M & A, const M & B, M & C)
{
// Stupid O(size(A) * size(B)) to do it
// Alec: This should be implemented by using unique and sort like `setdiff`
M dyn_C(A.size() > B.size() ? A.size() : B.size(),1);
// count of intersects
int c = 0;
// Loop over A
for(int i = 0;i<A.size();i++)
{
// Loop over B
for(int j = 0;j<B.size();j++)
{
if(A(i) == B(j))
{
dyn_C(c) = A(i);
c++;
}
}
}
// resize output
C.resize(c,1);
// Loop over intersects
for(int i = 0;i<c;i++)
{
C(i) = dyn_C(i);
}
}
template <class M>
IGL_INLINE M igl::intersect(const M & A, const M & B)
{
M C;
intersect(A,B,C);
return C;
}
#ifdef IGL_STATIC_LIBRARY
// Explicit template instantiation
template Eigen::Matrix<int, -1, 1, 0, -1, 1> igl::intersect<Eigen::Matrix<int, -1, 1, 0, -1, 1> >(Eigen::Matrix<int, -1, 1, 0, -1, 1> const&, Eigen::Matrix<int, -1, 1, 0, -1, 1> const&);
#endif