Added libigl library files (header-only library)

xs/src/igl/column_to_quats.cpp

@@ -0,0 +1,27 @@
+// 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 "column_to_quats.h"
+IGL_INLINE bool igl::column_to_quats(
+  const Eigen::VectorXd & Q,
+  std::vector<
+    Eigen::Quaterniond,Eigen::aligned_allocator<Eigen::Quaterniond> > & vQ)
+{
+  using namespace Eigen;
+  if(Q.size() % 4 != 0)
+  {
+    return false;
+  }
+  const int nQ = Q.size()/4;
+  vQ.resize(nQ);
+  for(int q=0;q<nQ;q++)
+  {
+    // Constructor uses wxyz
+    vQ[q] = Quaterniond( Q(q*4+3), Q(q*4+0), Q(q*4+1), Q(q*4+2));
+  }
+  return true;
+}