Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/knn.h

@@ -0,0 +1,52 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+//
+// Copyright (C) 2018 Gavin Barill <gavinpcb@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/
+
+#ifndef IGL_KNN
+#define IGL_KNN
+#include "igl_inline.h"
+#include <Eigen/Core>
+#include <vector>
+
+namespace igl
+{
+  // Given a 3D set of points P, an whole number k, and an octree
+  // find the indicies of the k nearest neighbors for each point in P.
+  // Note that each point is its own neighbor.
+  //
+  // The octree data structures used in this function are intended to be the
+  // same ones output from igl::octree
+  //
+  // Inputs:
+  //   P  #P by 3 list of point locations
+  //   k  number of neighbors to find
+  //   point_indices  a vector of vectors, where the ith entry is a vector of
+  //                  the indices into P that are the ith octree cell's points
+  //   CH     #OctreeCells by 8, where the ith row is the indices of
+  //          the ith octree cell's children
+  //   CN     #OctreeCells by 3, where the ith row is a 3d row vector
+  //          representing the position of the ith cell's center
+  //   W      #OctreeCells, a vector where the ith entry is the width
+  //          of the ith octree cell
+  // Outputs:
+  //   I  #P by k list of k-nearest-neighbor indices into P
+  template <typename DerivedP, typename KType, typename IndexType,
+    typename DerivedCH, typename DerivedCN, typename DerivedW,
+    typename DerivedI>
+  IGL_INLINE void knn(const Eigen::MatrixBase<DerivedP>& P,
+    const KType & k,
+    const std::vector<std::vector<IndexType> > & point_indices,
+    const Eigen::MatrixBase<DerivedCH>& CH,
+    const Eigen::MatrixBase<DerivedCN>& CN,
+    const Eigen::MatrixBase<DerivedW>& W,
+    Eigen::PlainObjectBase<DerivedI> & I);
+}
+#ifndef IGL_STATIC_LIBRARY
+#  include "knn.cpp"
+#endif
+#endif
+