---

math/real.h

Go to the documentation of this file.

#ifndef MATH_REAL_H
#define MATH_REAL_H

/*

  GLT OpenGL C++ Toolkit (LGPL)
  Copyright (C) 2000-2002 Nigel Stewart  

  Email: nigels.com@gmail.com   
  WWW:   http://www.nigels.com/glt/

  This library is free software; you can redistribute it and/or
  modify it under the terms of 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.

  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 GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*/

#include <glt/config.h>

#include <cfloat>
#include <cmath>

//
// Basic types, constants
// and functions
//

// Constants borrowed from PHP

#define M_PI        3.14159265358979323846
#define M_E         2.7182818284590452354
#define M_LOG2E     1.4426950408889634074
#define M_LOG10E    0.43429448190325182765
#define M_LN2       0.69314718055994530942
#define M_LN10      2.30258509299404568402
#define M_PI_2      1.57079632679489661923
#define M_PI_4      0.78539816339744830962
#define M_1_PI      0.31830988618379067154
#define M_2_PI      0.63661977236758134308

#ifndef M_SQRTPI
#define M_SQRTPI    1.77245385090551602729
#endif

#define M_2_SQRTPI  1.12837916709551257390
#define M_SQRT2     1.41421356237309504880

#ifndef M_SQRT3
#define M_SQRT3     1.73205080756887729352
#endif

#define M_SQRT1_2   0.70710678118654752440
#define M_LNPI      1.14472988584940017414
#define M_EULER     0.57721566490153286061

// Other useful constants

#define M_PI_DEG    (M_PI/180.0)
#define M_DEG_PI    (180.0/M_PI)
#define M_2PI       (2.0*M_PI)

template <class A>              A SQ(A a) { return a*a; }

//template <class A, class B>       A SIGN(A a, B b) { return b<0?  -a: a; }

template <class A> bool SAME_SIGN(A a, A b) { return (a<0 && b<0   ||   a>0 && b>0); }
template <class A> A    CLAMP(const A x, const A min_v, const A max_v) { return x<min_v?  min_v: (x>max_v? max_v: x); }
template <class A> A    LERP(const A &a,const A &b,const double t)     { return a*(1.0-t) + b*t; }

//template <class A> const A &MIN(const A &a,const B &b) { return a<b ? a : b; }
//template <class A> const A &MAX(const A &a,const B &b) { return a>b ? a : b; }

//template <class A> const A &MIN(const A &a,const B &b,const C &c) { return a<b && a<c ? a : MIN(b,c); }
//template <class A> const A &MAX(const A &a,const B &b,const C &c) { return a>b && a>c ? a : MAX(b,c); }

#define MAX(x,y) (((x)>(y)) ? (x) : (y))
#define MIN(x,y) (((x)<(y)) ? (x) : (y))

#endif

---