quadrilateralcowboy/idlib/math/Ode.h
2020-06-12 14:06:25 -07:00

146 lines
4.4 KiB
C++

/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code (?Doom 3 Source Code?).
Doom 3 Source Code 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 3 of the License, or
(at your option) any later version.
Doom 3 Source Code 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 Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#ifndef __MATH_ODE_H__
#define __MATH_ODE_H__
/*
===============================================================================
Numerical solvers for ordinary differential equations.
===============================================================================
*/
//===============================================================
//
// idODE
//
//===============================================================
typedef void (*deriveFunction_t)( const float t, const void *userData, const float *state, float *derivatives );
class idODE {
public:
virtual ~idODE( void ) {}
virtual float Evaluate( const float *state, float *newState, float t0, float t1 ) = 0;
protected:
int dimension; // dimension in floats allocated for
deriveFunction_t derive; // derive function
const void * userData; // client data
};
//===============================================================
//
// idODE_Euler
//
//===============================================================
class idODE_Euler : public idODE {
public:
idODE_Euler( const int dim, const deriveFunction_t dr, const void *ud );
virtual ~idODE_Euler( void );
virtual float Evaluate( const float *state, float *newState, float t0, float t1 );
protected:
float * derivatives; // space to store derivatives
};
//===============================================================
//
// idODE_Midpoint
//
//===============================================================
class idODE_Midpoint : public idODE {
public:
idODE_Midpoint( const int dim, const deriveFunction_t dr, const void *ud );
virtual ~idODE_Midpoint( void );
virtual float Evaluate( const float *state, float *newState, float t0, float t1 );
protected:
float * tmpState;
float * derivatives; // space to store derivatives
};
//===============================================================
//
// idODE_RK4
//
//===============================================================
class idODE_RK4 : public idODE {
public:
idODE_RK4( const int dim, const deriveFunction_t dr, const void *ud );
virtual ~idODE_RK4( void );
virtual float Evaluate( const float *state, float *newState, float t0, float t1 );
protected:
float * tmpState;
float * d1; // derivatives
float * d2;
float * d3;
float * d4;
};
//===============================================================
//
// idODE_RK4Adaptive
//
//===============================================================
class idODE_RK4Adaptive : public idODE {
public:
idODE_RK4Adaptive( const int dim, const deriveFunction_t dr, const void *ud );
virtual ~idODE_RK4Adaptive( void );
virtual float Evaluate( const float *state, float *newState, float t0, float t1 );
void SetMaxError( const float err );
protected:
float maxError; // maximum allowed error
float * tmpState;
float * d1; // derivatives
float * d1half;
float * d2;
float * d3;
float * d4;
};
#endif /* !__MATH_ODE_H__ */