text: // 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/.
  #ifndef IGL_MASSMATRIX_INTRINSIC_H
  #define IGL_MASSMATRIX_INTRINSIC_H
  #include "igl_inline.h"
  #include "massmatrix.h"
  
  #include <Eigen/Dense>
  #include <Eigen/Sparse>
  
  namespace igl 
  {
  
    // Constructs the mass (area) matrix for a given mesh (V,F).
    //
    // Inputs:
    //   l  #l by simplex_size list of mesh edge lengths
    //   F  #F by simplex_size list of mesh elements (triangles or tetrahedra)
    //   type  one of the following ints:
    //     MASSMATRIX_TYPE_BARYCENTRIC  barycentric
    //     MASSMATRIX_TYPE_VORONOI voronoi-hybrid {default}
    //     MASSMATRIX_TYPE_FULL full {not implemented}
    // Outputs: 
    //   M  #V by #V mass matrix
    //
    // See also: adjacency_matrix
    //
    template <typename Derivedl, typename DerivedF, typename Scalar>
    IGL_INLINE void massmatrix_intrinsic(
      const Eigen::MatrixBase<Derivedl> & l, 
      const Eigen::MatrixBase<DerivedF> & F, 
      const MassMatrixType type,
      Eigen::SparseMatrix<Scalar>& M);
    // Inputs:
    //   n  number of vertices (>= F.maxCoeff()+1)
    template <typename Derivedl, typename DerivedF, typename Scalar>
    IGL_INLINE void massmatrix_intrinsic(
      const Eigen::MatrixBase<Derivedl> & l, 
      const Eigen::MatrixBase<DerivedF> & F, 
      const MassMatrixType type,
      const int n,
      Eigen::SparseMatrix<Scalar>& M);
  }
  
  #ifndef IGL_STATIC_LIBRARY
  #  include "massmatrix_intrinsic.cpp"
  #endif
  
  #endif
  
  
  