dust3d/third_party/libigl/include/igl/min_quad_with_fixed.h

180 lines
5.9 KiB
C++

// This file is part of libigl, a simple c++ geometry processing library.
//
// Copyright (C) 2014 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_MIN_QUAD_WITH_FIXED_H
#define IGL_MIN_QUAD_WITH_FIXED_H
#include "igl_inline.h"
#define EIGEN_YES_I_KNOW_SPARSE_MODULE_IS_NOT_STABLE_YET
#include <Eigen/Core>
#include <Eigen/Dense>
#include <Eigen/Sparse>
// Bug in unsupported/Eigen/SparseExtra needs iostream first
#include <iostream>
#include <unsupported/Eigen/SparseExtra>
namespace igl
{
template <typename T>
struct min_quad_with_fixed_data;
// Known Bugs: rows of Aeq **should probably** be linearly independent.
// During precomputation, the rows of a Aeq are checked via QR. But in case
// they're not then resulting probably will no longer be sparse: it will be
// slow.
//
// MIN_QUAD_WITH_FIXED Minimize a quadratic energy of the form
//
// trace( 0.5*Z'*A*Z + Z'*B + constant )
//
// subject to
//
// Z(known,:) = Y, and
// Aeq*Z = Beq
//
// Templates:
// T should be a eigen matrix primitive type like int or double
// Inputs:
// A n by n matrix of quadratic coefficients
// known list of indices to known rows in Z
// Y list of fixed values corresponding to known rows in Z
// Aeq m by n list of linear equality constraint coefficients
// pd flag specifying whether A(unknown,unknown) is positive definite
// Outputs:
// data factorization struct with all necessary information to solve
// using min_quad_with_fixed_solve
// Returns true on success, false on error
//
// Benchmark: For a harmonic solve on a mesh with 325K facets, matlab 2.2
// secs, igl/min_quad_with_fixed.h 7.1 secs
//
template <typename T, typename Derivedknown>
IGL_INLINE bool min_quad_with_fixed_precompute(
const Eigen::SparseMatrix<T>& A,
const Eigen::MatrixBase<Derivedknown> & known,
const Eigen::SparseMatrix<T>& Aeq,
const bool pd,
min_quad_with_fixed_data<T> & data
);
// Solves a system previously factored using min_quad_with_fixed_precompute
//
// Template:
// T type of sparse matrix (e.g. double)
// DerivedY type of Y (e.g. derived from VectorXd or MatrixXd)
// DerivedZ type of Z (e.g. derived from VectorXd or MatrixXd)
// Inputs:
// data factorization struct with all necessary precomputation to solve
// B n by k column of linear coefficients
// Y b by k list of constant fixed values
// Beq m by k list of linear equality constraint constant values
// Outputs:
// Z n by k solution
// sol #unknowns+#lagrange by k solution to linear system
// Returns true on success, false on error
template <
typename T,
typename DerivedB,
typename DerivedY,
typename DerivedBeq,
typename DerivedZ,
typename Derivedsol>
IGL_INLINE bool min_quad_with_fixed_solve(
const min_quad_with_fixed_data<T> & data,
const Eigen::MatrixBase<DerivedB> & B,
const Eigen::MatrixBase<DerivedY> & Y,
const Eigen::MatrixBase<DerivedBeq> & Beq,
Eigen::PlainObjectBase<DerivedZ> & Z,
Eigen::PlainObjectBase<Derivedsol> & sol);
// Wrapper without sol
template <
typename T,
typename DerivedB,
typename DerivedY,
typename DerivedBeq,
typename DerivedZ>
IGL_INLINE bool min_quad_with_fixed_solve(
const min_quad_with_fixed_data<T> & data,
const Eigen::MatrixBase<DerivedB> & B,
const Eigen::MatrixBase<DerivedY> & Y,
const Eigen::MatrixBase<DerivedBeq> & Beq,
Eigen::PlainObjectBase<DerivedZ> & Z);
template <
typename T,
typename Derivedknown,
typename DerivedB,
typename DerivedY,
typename DerivedBeq,
typename DerivedZ>
IGL_INLINE bool min_quad_with_fixed(
const Eigen::SparseMatrix<T>& A,
const Eigen::MatrixBase<DerivedB> & B,
const Eigen::MatrixBase<Derivedknown> & known,
const Eigen::MatrixBase<DerivedY> & Y,
const Eigen::SparseMatrix<T>& Aeq,
const Eigen::MatrixBase<DerivedBeq> & Beq,
const bool pd,
Eigen::PlainObjectBase<DerivedZ> & Z);
}
template <typename T>
struct igl::min_quad_with_fixed_data
{
// Size of original system: number of unknowns + number of knowns
int n;
// Whether A(unknown,unknown) is positive definite
bool Auu_pd;
// Whether A(unknown,unknown) is symmetric
bool Auu_sym;
// Indices of known variables
Eigen::VectorXi known;
// Indices of unknown variables
Eigen::VectorXi unknown;
// Indices of lagrange variables
Eigen::VectorXi lagrange;
// Indices of unknown variable followed by Indices of lagrange variables
Eigen::VectorXi unknown_lagrange;
// Matrix multiplied against Y when constructing right hand side
Eigen::SparseMatrix<T> preY;
enum SolverType
{
LLT = 0,
LDLT = 1,
LU = 2,
QR_LLT = 3,
NUM_SOLVER_TYPES = 4
} solver_type;
// Solvers
Eigen::SimplicialLLT <Eigen::SparseMatrix<T > > llt;
Eigen::SimplicialLDLT<Eigen::SparseMatrix<T > > ldlt;
Eigen::SparseLU<Eigen::SparseMatrix<T, Eigen::ColMajor>, Eigen::COLAMDOrdering<int> > lu;
// QR factorization
// Are rows of Aeq linearly independent?
bool Aeq_li;
// Columns of Aeq corresponding to unknowns
int neq;
Eigen::SparseQR<Eigen::SparseMatrix<T>, Eigen::COLAMDOrdering<int> > AeqTQR;
Eigen::SparseMatrix<T> Aeqk;
Eigen::SparseMatrix<T> Aequ;
Eigen::SparseMatrix<T> Auu;
Eigen::SparseMatrix<T> AeqTQ1;
Eigen::SparseMatrix<T> AeqTQ1T;
Eigen::SparseMatrix<T> AeqTQ2;
Eigen::SparseMatrix<T> AeqTQ2T;
Eigen::SparseMatrix<T> AeqTR1;
Eigen::SparseMatrix<T> AeqTR1T;
Eigen::SparseMatrix<T> AeqTE;
Eigen::SparseMatrix<T> AeqTET;
// Debug
Eigen::SparseMatrix<T> NA;
Eigen::Matrix<T,Eigen::Dynamic,Eigen::Dynamic> NB;
};
#ifndef IGL_STATIC_LIBRARY
# include "min_quad_with_fixed.cpp"
#endif
#endif