OdeSolver.h

// This file is a part of the OpenSurgSim project.
// Copyright 2013, SimQuest Solutions Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef SURGSIM_MATH_ODESOLVER_H
#define SURGSIM_MATH_ODESOLVER_H

#include <functional>
#include <unordered_map>

#include <boost/assign/list_of.hpp> // for 'map_list_of()'

#include "SurgSim/Math/LinearSparseSolveAndInverse.h"
#include "SurgSim/Math/Matrix.h"
#include "SurgSim/Math/OdeEquation.h"

namespace SurgSim
{

namespace Math
{

enum IntegrationScheme
{
    INTEGRATIONSCHEME_STATIC = 0,
    INTEGRATIONSCHEME_LINEAR_STATIC,
    INTEGRATIONSCHEME_EULER_EXPLICIT,
    INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT,
    INTEGRATIONSCHEME_EULER_EXPLICIT_MODIFIED,
    INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT_MODIFIED,
    INTEGRATIONSCHEME_EULER_IMPLICIT,
    INTEGRATIONSCHEME_LINEAR_EULER_IMPLICIT,
    INTEGRATIONSCHEME_RUNGE_KUTTA_4,
    INTEGRATIONSCHEME_LINEAR_RUNGE_KUTTA_4,
    MAX_INTEGRATIONSCHEMES
};

const std::unordered_map<IntegrationScheme, std::string, std::hash<int>> IntegrationSchemeNames =
            boost::assign::map_list_of
            (INTEGRATIONSCHEME_STATIC, "INTEGRATIONSCHEME_STATIC")
            (INTEGRATIONSCHEME_LINEAR_STATIC, "INTEGRATIONSCHEME_LINEAR_STATIC")
            (INTEGRATIONSCHEME_EULER_EXPLICIT, "INTEGRATIONSCHEME_EULER_EXPLICIT")
            (INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT, "INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT")
            (INTEGRATIONSCHEME_EULER_EXPLICIT_MODIFIED, "INTEGRATIONSCHEME_EULER_EXPLICIT_MODIFIED")
            (INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT_MODIFIED, "INTEGRATIONSCHEME_LINEAR_EULER_EXPLICIT_MODIFIED")
            (INTEGRATIONSCHEME_EULER_IMPLICIT, "INTEGRATIONSCHEME_EULER_IMPLICIT")
            (INTEGRATIONSCHEME_LINEAR_EULER_IMPLICIT, "INTEGRATIONSCHEME_LINEAR_EULER_IMPLICIT")
            (INTEGRATIONSCHEME_RUNGE_KUTTA_4, "INTEGRATIONSCHEME_RUNGE_KUTTA_4")
            (INTEGRATIONSCHEME_LINEAR_RUNGE_KUTTA_4, "INTEGRATIONSCHEME_LINEAR_RUNGE_KUTTA_4");

class OdeSolver
{
public:
    explicit OdeSolver(OdeEquation* equation);

    virtual ~OdeSolver()
    {}

    const std::string getName() const;

    void setLinearSolver(std::shared_ptr<LinearSparseSolveAndInverse> linearSolver);

    std::shared_ptr<LinearSparseSolveAndInverse> getLinearSolver() const;

    virtual void solve(double dt, const OdeState& currentState, OdeState* newState, bool computeCompliance = true) = 0;

    void computeMatrices(double dt, const OdeState& state, bool computeCompliance = true);

    const SparseMatrix& getSystemMatrix() const;

    const Matrix& getComplianceMatrix() const;

protected:
    virtual void assembleLinearSystem(double dt, const OdeState& state, const OdeState& newState,
                                      bool computeRHS = true) = 0;

    void computeComplianceMatrixFromSystemMatrix(const OdeState& state);

    std::string m_name;

    OdeEquation& m_equation;

    std::shared_ptr<LinearSparseSolveAndInverse> m_linearSolver;

    SparseMatrix m_systemMatrix;

    Vector m_solution, m_rhs;

    Matrix m_complianceMatrix;
};

}; // namespace Math

}; // namespace SurgSim

#endif // SURGSIM_MATH_ODESOLVER_H