assimp.assimp/include/assimp/MathFunctions.h

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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 {

/// @brief  Will return the greatest common divisor.
/// @param  a   [in] Value a.
/// @param  b   [in] Value b.
/// @return The greatest common divisor.
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;
	}
}

/// @brief  Will return the greatest common divisor.
/// @param  a   [in] Value a.
/// @param  b   [in] Value b.
/// @return The greatest common divisor.
template < typename IntegerType >
inline IntegerType lcm( IntegerType a, IntegerType b ) {
	const IntegerType t = gcd (a,b);
	if (!t) {
        return t;
    }
	return a / t * b;
}
/// @brief  Will return the smallest epsilon-value for the requested type.
/// @return The numercical limit epsilon depending on its type.
template<class T>
inline T getEpsilon() {
    return std::numeric_limits<T>::epsilon();
}

/// @brief  Will return the constant PI for the requested type.
/// @return Pi
template<class T>
inline T aiPi() {
    return static_cast<T>(3.14159265358979323846);
}

} // namespace Math
} // namespace Assimp