lumosquad/CG_SOLVER.h
2025-07-26 22:14:37 +02:00

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4.7 KiB
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///////////////////////////////////////////////////////////////////////////////////
// File : CG_SOLVER.h
///////////////////////////////////////////////////////////////////////////////////
//
// LumosQuad - A Lightning Generator
// Copyright 2007
// The University of North Carolina at Chapel Hill
//
///////////////////////////////////////////////////////////////////////////////////
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
// The University of North Carolina at Chapel Hill makes no representations
// about the suitability of this software for any purpose. It is provided
// "as is" without express or implied warranty.
//
// Permission to use, copy, modify and distribute this software and its
// documentation for educational, research and non-profit purposes, without
// fee, and without a written agreement is hereby granted, provided that the
// above copyright notice and the following three paragraphs appear in all
// copies.
//
// THE UNIVERSITY OF NORTH CAROLINA SPECIFICALLY DISCLAIM ANY WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN
// "AS IS" BASIS, AND THE UNIVERSITY OF NORTH CAROLINA HAS NO OBLIGATION TO
// PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
//
// Please send questions and comments about LumosQuad to kim@cs.unc.edu.
//
///////////////////////////////////////////////////////////////////////////////////
//
// This program uses OpenEXR, which has the following restrictions:
//
// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
// Digital Ltd. LLC
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Industrial Light & Magic nor the names of
// its contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
#ifndef CG_SOLVER_H
#define CG_SOLVER_H
#include "CELL.h"
#include <cmath>
#include <list>
using namespace std;
////////////////////////////////////////////////////////////////////
/// \brief Conjugate gradient Poisson solver.
////////////////////////////////////////////////////////////////////
class CG_SOLVER
{
public:
//! constructor
CG_SOLVER(int maxDepth, int iterations = 10, int digits = 8);
//! destructor
virtual ~CG_SOLVER();
//! solve the Poisson problem
virtual int solve(list<CELL*> cells);
//! calculate the residual
float calcResidual(list<CELL*> cells);
//! accessor for the maximum number of iterations
int& iterations() { return _iterations; };
protected:
int _iterations; ///< maximum number of iterations
int _digits; ///< desired digits of precision
////////////////////////////////////////////////////////////////
// conjugate gradient arrays
////////////////////////////////////////////////////////////////
float* _direction; ///< conjugate gradient 'd' array
float* _potential; ///< conjugate gradient solution, 'x' array
float* _residual; ///< conjugate gradient residual, 'r' array
float* _q; ///< conjugate gradient 'q' array
int _arraySize; ///< currently allocated array size
int _listSize; ///< current system size
//! compute stencils once and store
void calcStencils(list<CELL*> cells);
//! reallocate the scratch arrays
virtual void reallocate();
//! physical lengths of various cell sizes
float* _dx;
};
#endif