Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/triangle_fan.cpp

@@ -0,0 +1,54 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+// 
+// Copyright (C) 2015 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 "triangle_fan.h"
+#include "exterior_edges.h"
+#include "list_to_matrix.h"
+
+IGL_INLINE void igl::triangle_fan(
+  const Eigen::MatrixXi & E,
+  Eigen::MatrixXi & cap)
+{
+  using namespace std;
+  using namespace Eigen;
+
+  // Handle lame base case
+  if(E.size() == 0)
+  {
+    cap.resize(0,E.cols()+1);
+    return;
+  }
+  // "Triangulate" aka "close" the E trivially with facets
+  // Note: in 2D we need to know if E endpoints are incoming or
+  // outgoing (left or right). Thus this will not work.
+  assert(E.cols() == 2);
+  // Arbitrary starting vertex
+  //int s = E(int(((double)rand() / RAND_MAX)*E.rows()),0);
+  int s = E(rand()%E.rows(),0);
+  vector<vector<int> >  lcap;
+  for(int i = 0;i<E.rows();i++)
+  {
+    // Skip edges incident on s (they would be zero-area)
+    if(E(i,0) == s || E(i,1) == s)
+    {
+      continue;
+    }
+    vector<int> e(3);
+    e[0] = s;
+    e[1] = E(i,0);
+    e[2] = E(i,1);
+    lcap.push_back(e);
+  }
+  list_to_matrix(lcap,cap);
+}
+
+IGL_INLINE Eigen::MatrixXi igl::triangle_fan( const Eigen::MatrixXi & E)
+{
+  Eigen::MatrixXi cap;
+  triangle_fan(E,cap);
+  return cap;
+}