Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/bfs.cpp

@@ -0,0 +1,93 @@
+#include "bfs.h"
+#include "list_to_matrix.h"
+#include <vector>
+#include <queue>
+
+template <
+  typename AType,
+  typename DerivedD,
+  typename DerivedP>
+IGL_INLINE void igl::bfs(
+  const AType & A,
+  const size_t s,
+  Eigen::PlainObjectBase<DerivedD> & D,
+  Eigen::PlainObjectBase<DerivedP> & P)
+{
+  std::vector<typename DerivedD::Scalar> vD;
+  std::vector<typename DerivedP::Scalar> vP;
+  bfs(A,s,vD,vP);
+  list_to_matrix(vD,D);
+  list_to_matrix(vP,P);
+}
+
+template <
+  typename AType,
+  typename DType,
+  typename PType>
+IGL_INLINE void igl::bfs(
+  const std::vector<std::vector<AType> > & A,
+  const size_t s,
+  std::vector<DType> & D,
+  std::vector<PType> & P)
+{
+  // number of nodes
+  int N = s+1;
+  for(const auto & Ai : A) for(const auto & a : Ai) N = std::max(N,a+1);
+  std::vector<bool> seen(N,false);
+  P.resize(N,-1);
+  std::queue<std::pair<int,int> > Q;
+  Q.push({s,-1});
+  while(!Q.empty())
+  {
+    const int f = Q.front().first;
+    const int p = Q.front().second;
+    Q.pop();
+    if(seen[f])
+    {
+      continue;
+    }
+    D.push_back(f);
+    P[f] = p;
+    seen[f] = true;
+    for(const auto & n : A[f]) Q.push({n,f});
+  }
+}
+
+
+template <
+  typename AType,
+  typename DType,
+  typename PType>
+IGL_INLINE void igl::bfs(
+  const Eigen::SparseMatrix<AType> & A,
+  const size_t s,
+  std::vector<DType> & D,
+  std::vector<PType> & P)
+{
+  // number of nodes
+  int N = A.rows();
+  assert(A.rows() == A.cols());
+  std::vector<bool> seen(N,false);
+  P.resize(N,-1);
+  std::queue<std::pair<int,int> > Q;
+  Q.push({s,-1});
+  while(!Q.empty())
+  {
+    const int f = Q.front().first;
+    const int p = Q.front().second;
+    Q.pop();
+    if(seen[f])
+    {
+      continue;
+    }
+    D.push_back(f);
+    P[f] = p;
+    seen[f] = true;
+    for(typename Eigen::SparseMatrix<AType>::InnerIterator it (A,f); it; ++it)
+    {
+      if(it.value()) Q.push({it.index(),f});
+    }
+  }
+
+}
+