reactphysics3d/src/mathematics/mathematics_functions.h

/********************************************************************************
* ReactPhysics3D physics library, http://code.google.com/p/reactphysics3d/      *
* Copyright (c) 2010-2013 Daniel Chappuis                                       *
*********************************************************************************
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* This software is provided 'as-is', without any express or implied warranty.   *
* In no event will the authors be held liable for any damages arising from the  *
* use of this software.                                                         *
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* including commercial applications, and to alter it and redistribute it        *
* freely, subject to the following restrictions:                                *
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* 1. The origin of this software must not be misrepresented; you must not claim *
*    that you wrote the original software. If you use this software in a        *
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#ifndef REACTPHYSICS3D_MATHEMATICS_FUNCTIONS_H
#define REACTPHYSICS3D_MATHEMATICS_FUNCTIONS_H

// Libraries
#include "../configuration.h"
#include "../decimal.h"
#include <algorithm>

/// ReactPhysics3D namespace
namespace reactphysics3d {

// ---------- Mathematics functions ---------- //

/// Function to test if two real numbers are (almost) equal
/// We test if two numbers a and b are such that (a-b) are in [-EPSILON; EPSILON]
inline bool approxEqual(decimal a, decimal b, decimal epsilon = MACHINE_EPSILON) {

    decimal difference = a - b;
    return (difference < epsilon && difference > -epsilon);
}

/// Function that returns the result of the "value" clamped by
/// two others values "lowerLimit" and "upperLimit"
inline decimal clamp(decimal value, decimal lowerLimit, decimal upperLimit) {
    assert(lowerLimit <= upperLimit);
    return std::min(std::max(value, lowerLimit), upperLimit);
}

}



#endif