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/*
* This source file is part of MyGUI. For the latest info, see http://mygui.info/
* Distributed under the MIT License
* (See accompanying file COPYING.MIT or copy at http://opensource.org/licenses/MIT)
*/
#ifndef MYGUI_BITWISE_H_
#define MYGUI_BITWISE_H_
#include "MyGUI_Prerequest.h"
namespace MyGUI
{
class Bitwise
{
public:
/** Returns the closest power-of-two number greater or equal to value.
*/
template<typename Type>
static MYGUI_FORCEINLINE Type firstPO2From(Type _value)
{
--_value;
_value |= _value >> 16;
_value |= _value >> 8;
_value |= _value >> 4;
_value |= _value >> 2;
_value |= _value >> 1;
++_value;
return _value;
}
/** Determines whether the number is power-of-two or not. */
template<typename Type>
static MYGUI_FORCEINLINE bool isPO2(Type _value)
{
return (_value & (_value - 1)) == 0;
}
/** Returns the number of bits a pattern must be shifted right by to
remove right-hand zeros.
*/
template<typename Type>
static MYGUI_FORCEINLINE size_t getBitShift(Type _mask)
{
if (_mask == 0)
return 0;
size_t result = 0;
while ((_mask & 1) == 0)
{
++result;
_mask >>= 1;
}
return result;
}
};
} // namespace MyGUI
#endif // MYGUI_BITWISE_H_
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