assimp/include/assimp/MathFunctions.h

/*
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Open Asset Import Library (assimp)
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*/

#pragma once

#ifdef __GNUC__
#   pragma GCC system_header
#endif

/** @file  MathFunctions.h
*  @brief Implementation of math utility functions.
 *
*/

#include <limits>

namespace Assimp {
namespace Math {

// TODO: use binary GCD for unsigned integers ....
template < typename IntegerType >
inline
IntegerType gcd( IntegerType a, IntegerType b ) {
	const IntegerType zero = (IntegerType)0;
	while ( true ) {
		if ( a == zero )
			return b;
		b %= a;

		if ( b == zero )
			return a;
		a %= b;
	}
}

template < typename IntegerType >
inline
IntegerType lcm( IntegerType a, IntegerType b ) {
	const IntegerType t = gcd (a,b);
	if (!t)
        return t;
	return a / t * b;
}

template<class T>
inline
T getEpsilon() {
    return std::numeric_limits<T>::epsilon();
}

}
}