pxmlw6n2f/Gazebo_Distributed_TCP/deps/opende/include/ode/misc.h

156 lines
5.0 KiB
C

/*************************************************************************
* *
* Open Dynamics Engine, Copyright (C) 2001,2002 Russell L. Smith. *
* All rights reserved. Email: russ@q12.org Web: www.q12.org *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of EITHER: *
* (1) The GNU Lesser General Public License as published by the Free *
* Software Foundation; either version 2.1 of the License, or (at *
* your option) any later version. The text of the GNU Lesser *
* General Public License is included with this library in the *
* file LICENSE.TXT. *
* (2) The BSD-style license that is included with this library in *
* the file LICENSE-BSD.TXT. *
* *
* This library 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 files *
* LICENSE.TXT and LICENSE-BSD.TXT for more details. *
* *
*************************************************************************/
/* miscellaneous math functions. these are mostly useful for testing */
#ifndef _ODE_MISC_H_
#define _ODE_MISC_H_
#include <ode/common.h>
#ifdef __cplusplus
extern "C" {
#endif
/* return 1 if the random number generator is working. */
ODE_API int dTestRand(void);
/* return next 32 bit random number. this uses a not-very-random linear
* congruential method.
*/
ODE_API unsigned long dRand(void);
/* get and set the current random number seed. */
ODE_API unsigned long dRandGetSeed(void);
ODE_API void dRandSetSeed (unsigned long s);
/* return a random integer between 0..n-1. the distribution will get worse
* as n approaches 2^32.
*/
ODE_API int dRandInt (int n);
/* return a random real number between 0..1 */
ODE_API dReal dRandReal(void);
/* print out a matrix */
#ifdef __cplusplus
ODE_API void dPrintMatrix (const dReal *A, int n, int m, char *fmt = "%10.4f ",
FILE *f=stdout);
ODE_API void dPrintIntMatrix (const int *A, int n, int m, char *fmt = "%5d ",
FILE *f=stdout);
#else
ODE_API void dPrintMatrix (const dReal *A, int n, int m, char *fmt, FILE *f);
ODE_API void dPrintIntMatrix (const int *A, int n, int m, char *fmt, FILE *f);
#endif
/* make a random vector with entries between +/- range. A has n elements. */
ODE_API void dMakeRandomVector (dReal *A, int n, dReal range);
/* make a random matrix with entries between +/- range. A has size n*m. */
ODE_API void dMakeRandomMatrix (dReal *A, int n, int m, dReal range);
/* clear the upper triangle of a square matrix */
ODE_API void dClearUpperTriangle (dReal *A, int n);
/* return the maximum element difference between the two n*m matrices */
ODE_API dReal dMaxDifference (const dReal *A, const dReal *B, int n, int m);
/* return the maximum element difference between the lower triangle of two
* n*n matrices */
ODE_API dReal dMaxDifferenceLowerTriangle (const dReal *A, const dReal *B, int n);
/*!
* \brief dNormalizeAnglePositive
*
* Normalizes the angle to be 0 to 2*M_PI
* It takes and returns radians.
*/
static inline dReal dNormalizeAnglePositive(dReal angle)
{
return fmod(fmod(angle, 2.0*M_PI) + 2.0*M_PI, 2.0*M_PI);
}
/*!
* \brief normalize
*
* Normalizes the angle from [0, 2*M_PI] to [-M_PI, +M_PI] circle
* It takes and returns radians.
*
*/
static inline dReal dNormalizeAngle(dReal angle)
{
dReal a = dNormalizeAnglePositive(angle);
if (a > M_PI)
a -= 2.0 *M_PI;
return a;
}
/*!
* \function
* \brief dShortestAngularDistance
*
* Given 2 angles, this returns the shortest angular
* difference. The inputs and ouputs are of course radians.
*
* The result
* would always be -pi <= result <= pi. Adding the result
* to "from" will always get you an equivelent angle to "to".
*/
static inline dReal dShortestAngularDistance(dReal from, dReal to)
{
dReal result = dNormalizeAngle(dNormalizeAnglePositive(dNormalizeAnglePositive(to) -
dNormalizeAnglePositive(from)));
return result;
}
/*!
* \function
* \brief dShortestAngularDistanceUpdate
*
* Given 2 angles, this returns the shortest angular
* difference. The inputs and ouputs are radians.
*
* This function returns (from + delta) where delta is in the range of [-pi, pi].
* However, if |delta| > tol, then this function simply returns incoming parameter "to".
*
*/
static inline dReal dShortestAngularDistanceUpdate(dReal from, dReal to, dReal tol = 0.3)
{
dReal result = dShortestAngularDistance(from, to);
if (dFabs(result) > tol)
return to;
else
return from + result;
}
#ifdef __cplusplus
}
#endif
#endif