///////////////////////////////////////////////////////////////////////////////////
/// OpenGL Mathematics (glm.g-truc.net)
///
/// Copyright (c) 2005 - 2015 G-Truc Creation (www.g-truc.net)
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to deal
/// in the Software without restriction, including without limitation the rights
/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/// copies of the Software, and to permit persons to whom the Software is
/// furnished to do so, subject to the following conditions:
/// 
/// The above copyright notice and this permission notice shall be included in
/// all copies or substantial portions of the Software.
/// 
/// Restrictions:
///             By making use of the Software for military purposes, you choose to make
///             a Bunny unhappy.
/// 
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
/// THE SOFTWARE.
///
/// @ref gtx_bit
/// @file glm/gtx/bit.inl
/// @date 2014-11-25 / 2014-11-25
/// @author Christophe Riccio
///////////////////////////////////////////////////////////////////////////////////

namespace glm
{
        ///////////////////
        // highestBitValue

        template <typename genIUType>
        GLM_FUNC_QUALIFIER genIUType highestBitValue(genIUType Value)
        {
                genIUType tmp = Value;
                genIUType result = genIUType(0);
                while(tmp)
                {
                        result = (tmp & (~tmp + 1)); // grab lowest bit
                        tmp &= ~result; // clear lowest bit
                }
                return result;
        }

        template <typename T, precision P, template <typename, precision> class vecType>
        GLM_FUNC_QUALIFIER vecType<T, P> highestBitValue(vecType<T, P> const & v)
        {
                return detail::functor1<T, T, P, vecType>::call(highestBitValue, v);
        }

        ///////////////////
        // powerOfTwoAbove

        template <typename genType>
        GLM_FUNC_QUALIFIER genType powerOfTwoAbove(genType value)
        {
                return isPowerOfTwo(value) ? value : highestBitValue(value) << 1;
        }

        template <typename T, precision P, template <typename, precision> class vecType>
        GLM_FUNC_QUALIFIER vecType<T, P> powerOfTwoAbove(vecType<T, P> const & v)
        {
                return detail::functor1<T, T, P, vecType>::call(powerOfTwoAbove, v);
        }

        ///////////////////
        // powerOfTwoBelow

        template <typename genType>
        GLM_FUNC_QUALIFIER genType powerOfTwoBelow(genType value)
        {
                return isPowerOfTwo(value) ? value : highestBitValue(value);
        }

        template <typename T, precision P, template <typename, precision> class vecType>
        GLM_FUNC_QUALIFIER vecType<T, P> powerOfTwoBelow(vecType<T, P> const & v)
        {
                return detail::functor1<T, T, P, vecType>::call(powerOfTwoBelow, v);
        }

        /////////////////////
        // powerOfTwoNearest

        template <typename genType>
        GLM_FUNC_QUALIFIER genType powerOfTwoNearest(genType value)
        {
                if(isPowerOfTwo(value))
                        return value;

                genType const prev = highestBitValue(value);
                genType const next = prev << 1;
                return (next - value) < (value - prev) ? next : prev;
        }

        template <typename T, precision P, template <typename, precision> class vecType>
        GLM_FUNC_QUALIFIER vecType<T, P> powerOfTwoNearest(vecType<T, P> const & v)
        {
                return detail::functor1<T, T, P, vecType>::call(powerOfTwoNearest, v);
        }

}//namespace glm