Merged branch 'dev_native' into lm_sla_supports_auto

Added igl library files

src/igl/arap_linear_block.h

@@ -0,0 +1,78 @@
+// 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_ARAP_LINEAR_BLOCK_H
+#define IGL_ARAP_LINEAR_BLOCK_H
+#include "igl_inline.h"
+
+#include <Eigen/Sparse>
+#include <igl/ARAPEnergyType.h>
+
+namespace igl
+{
+  // ARAP_LINEAR_BLOCK constructs a block of the matrix which constructs the
+  // linear terms of a given arap energy. When treating rotations as knowns
+  // (arranged in a column) then this constructs Kd of K such that the linear
+  // portion of the energy is as a column:
+  //   K * R = [Kx Z  ... Ky Z  ... 
+  //            Z  Kx ... Z  Ky ... 
+  //            ... ]
+  // These blocks are also used to build the "covariance scatter matrices".
+  // Here we want to build a scatter matrix that multiplies against positions
+  // (treated as known) producing covariance matrices to fit each rotation.
+  // Notice that in the case of the RHS of the poisson solve the rotations are
+  // known and the positions unknown, and vice versa for rotation fitting.
+  // These linear block just relate the rotations to the positions, linearly in
+  // each.
+  //
+  // Templates:
+  //   MatV  vertex position matrix, e.g. Eigen::MatrixXd
+  //   MatF  face index matrix, e.g. Eigen::MatrixXd
+  //   Scalar  e.g. double
+  // Inputs:
+  //   V  #V by dim list of initial domain positions
+  //   F  #F by #simplex size list of triangle indices into V
+  //   d  coordinate of linear constructor to build
+  //   energy  ARAPEnergyType enum value defining which energy is being used.
+  //     See ARAPEnergyType.h for valid options and explanations.
+  // Outputs:
+  //   Kd  #V by #V/#F block of the linear constructor matrix corresponding to
+  //     coordinate d
+  //
+  template <typename MatV, typename MatF, typename Scalar>
+  IGL_INLINE void arap_linear_block(
+    const MatV & V,
+    const MatF & F,
+    const int d,
+    const igl::ARAPEnergyType energy,
+    Eigen::SparseMatrix<Scalar> & Kd);
+  // Helper functions for each energy type
+  template <typename MatV, typename MatF, typename Scalar>
+  IGL_INLINE void arap_linear_block_spokes(
+    const MatV & V,
+    const MatF & F,
+    const int d,
+    Eigen::SparseMatrix<Scalar> & Kd);
+  template <typename MatV, typename MatF, typename Scalar>
+  IGL_INLINE void arap_linear_block_spokes_and_rims(
+    const MatV & V,
+    const MatF & F,
+    const int d,
+    Eigen::SparseMatrix<Scalar> & Kd);
+  template <typename MatV, typename MatF, typename Scalar>
+  IGL_INLINE void arap_linear_block_elements(
+    const MatV & V,
+    const MatF & F,
+    const int d,
+    Eigen::SparseMatrix<Scalar> & Kd);
+}
+
+#ifndef IGL_STATIC_LIBRARY
+#  include "arap_linear_block.cpp"
+#endif
+
+#endif