magnum/src/Math/BoolVector.h

#ifndef Magnum_Math_BoolVector_h
#define Magnum_Math_BoolVector_h
/*
    This file is part of Magnum.

    Copyright © 2010, 2011, 2012, 2013 Vladimír Vondruš <mosra@centrum.cz>

    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.

    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.
*/

/** @file
 * @brief Class Magnum::Math::BoolVector
 */

#include <Utility/Debug.h>
#include <corradeCompatibility.h>

#include "Types.h"

namespace Magnum { namespace Math {

namespace Implementation {
    template<std::size_t ...> struct Sequence {};

    #ifndef DOXYGEN_GENERATING_OUTPUT
    /* E.g. GenerateSequence<3>::Type is Sequence<0, 1, 2> */
    template<std::size_t N, std::size_t ...sequence> struct GenerateSequence:
        GenerateSequence<N-1, N-1, sequence...> {};

    template<std::size_t ...sequence> struct GenerateSequence<0, sequence...> {
        typedef Sequence<sequence...> Type;
    };
    #endif

    template<class T> inline constexpr T repeat(T value, std::size_t) { return value; }
}

/**
@brief %Vector storing boolean values
@tparam size    Bit count

Result of component-wise comparison from Vector. The boolean values are stored
as bits in array of unsigned bytes, unused bits have undefined value which
doesn't affect comparison or all() / none() / any() functions. See also
@ref matrix-vector for brief introduction.
*/
template<std::size_t size> class BoolVector {
    static_assert(size != 0, "BoolVector cannot have zero elements");

    public:
        static const std::size_t Size = size;               /**< @brief %Vector size */
        static const std::size_t DataSize = (size-1)/8+1;   /**< @brief %Vector storage size */

        /** @brief Construct zero-filled boolean vector */
        inline constexpr BoolVector(): _data() {}

        /**
         * @brief Construct boolean vector from segment values
         * @param first Value for first 8bit segment
         * @param next  Values for next Bbit segments
         */
        #ifdef DOXYGEN_GENERATING_OUTPUT
        template<class ...T> inline constexpr /*implicit*/ BoolVector(UnsignedByte first, T... next);
        #else
        template<class ...T, class U = typename std::enable_if<sizeof...(T)+1 == DataSize, bool>::type> inline constexpr /*implicit*/ BoolVector(UnsignedByte first, T... next): _data{first, UnsignedByte(next)...} {}
        #endif

        /** @brief Construct boolean vector with one value for all fields */
        #ifdef DOXYGEN_GENERATING_OUTPUT
        inline explicit BoolVector(T value);
        #else
        #ifndef CORRADE_GCC46_COMPATIBILITY
        template<class T, class U = typename std::enable_if<std::is_same<bool, T>::value && size != 1, bool>::type> inline constexpr explicit BoolVector(T value): BoolVector(typename Implementation::GenerateSequence<DataSize>::Type(), value ? FullSegmentMask : 0) {}
        #else
        template<class T, class U = typename std::enable_if<std::is_same<bool, T>::value && size != 1, bool>::type> inline explicit BoolVector(T value) {
            *this = BoolVector(typename Implementation::GenerateSequence<DataSize>::Type(), value ? FullSegmentMask : 0);
        }
        #endif
        #endif

        /** @brief Copy constructor */
        inline constexpr BoolVector(const BoolVector<size>&) = default;

        /** @brief Copy assignment */
        inline BoolVector<size>& operator=(const BoolVector<size>&) = default;

        /**
         * @brief Raw data
         * @return %Array of DataSize length
         *
         * @see operator[](), set()
         */
        inline UnsignedByte* data() { return _data; }
        inline constexpr const UnsignedByte* data() const { return _data; } /**< @overload */

        /** @brief Bit at given position */
        inline constexpr bool operator[](std::size_t i) const {
            return (_data[i/8] >> i%8) & 0x01;
        }

        /** @brief Set bit at given position */
        inline BoolVector<size>& set(std::size_t i, bool value) {
            _data[i/8] |= ((value & 0x01) << i%8);
            return *this;
        }

        /** @brief Equality comparison */
        inline bool operator==(const BoolVector<size>& other) const {
            for(std::size_t i = 0; i != size/8; ++i)
                if(_data[i] != other._data[i]) return false;

            /* Check last segment */
            if(size%8 && (_data[DataSize-1] & LastSegmentMask) != (other._data[DataSize-1] & LastSegmentMask))
                return false;

            return true;
        }

        /** @brief Non-equality comparison */
        inline bool operator!=(const BoolVector<size>& other) const {
            return !operator==(other);
        }

        /** @brief Whether all bits are set */
        bool all() const {
            /* Check all full segments */
            for(std::size_t i = 0; i != size/8; ++i)
                if(_data[i] != FullSegmentMask) return false;

            /* Check last segment */
            if(size%8 && (_data[DataSize-1] & LastSegmentMask) != LastSegmentMask)
                return false;

            return true;
        }

        /** @brief Whether no bits are set */
        bool none() const {
            /* Check all full segments */
            for(std::size_t i = 0; i != size/8; ++i)
                if(_data[i]) return false;

            /* Check last segment */
            if(size%8 && (_data[DataSize-1] & LastSegmentMask))
                return false;

            return true;
        }

        /** @brief Whether any bit is set */
        inline bool any() const {
            return !none();
        }

        /** @brief Bitwise inversion */
        inline BoolVector<size> operator~() const {
            BoolVector<size> out;

            for(std::size_t i = 0; i != DataSize; ++i)
                out._data[i] = ~_data[i];

            return out;
        }

        /**
         * @brief Bitwise AND and assign
         *
         * The computation is done in-place.
         */
        inline BoolVector<size>& operator&=(const BoolVector<size>& other) {
            for(std::size_t i = 0; i != DataSize; ++i)
                _data[i] &= other._data[i];

            return *this;
        }

        /**
         * @brief Bitwise AND
         *
         * @see operator&=()
         */
        inline BoolVector<size> operator&(const BoolVector<size>& other) const {
            return BoolVector<size>(*this) &= other;
        }

        /**
         * @brief Bitwise OR and assign
         *
         * The computation is done in-place.
         */
        inline BoolVector<size>& operator|=(const BoolVector<size>& other) {
            for(std::size_t i = 0; i != DataSize; ++i)
                _data[i] |= other._data[i];

            return *this;
        }

        /**
         * @brief Bitwise OR
         *
         * @see operator|=()
         */
        inline BoolVector<size> operator|(const BoolVector<size>& other) const {
            return BoolVector<size>(*this) |= other;
        }

        /**
         * @brief Bitwise XOR and assign
         *
         * The computation is done in-place.
         */
        inline BoolVector<size>& operator^=(const BoolVector<size>& other) {
            for(std::size_t i = 0; i != DataSize; ++i)
                _data[i] ^= other._data[i];

            return *this;
        }

        /**
         * @brief Bitwise XOR
         *
         * @see operator^=()
         */
        inline BoolVector<size> operator^(const BoolVector<size>& other) const {
            return BoolVector<size>(*this) ^= other;
        }

    private:
        enum: UnsignedByte {
            FullSegmentMask = 0xFF,
            LastSegmentMask = (1 << size%8) - 1
        };

        /* Implementation for Vector<size, T>::Vector(U) */
        template<std::size_t ...sequence> inline constexpr explicit BoolVector(Implementation::Sequence<sequence...>, UnsignedByte value): _data{Implementation::repeat(value, sequence)...} {}

        UnsignedByte _data[(size-1)/8+1];
};

/** @debugoperator{Magnum::Math::BoolVector} */
template<std::size_t size> Corrade::Utility::Debug operator<<(Corrade::Utility::Debug debug, const BoolVector<size>& value) {
    debug << "BoolVector(";
    debug.setFlag(Corrade::Utility::Debug::SpaceAfterEachValue, false);
    for(std::size_t i = 0; i != size; ++i) {
        if(i && !(i%8)) debug << " ";
        debug << (value[i] ? "1" : "0");
    }
    debug << ")";
    debug.setFlag(Corrade::Utility::Debug::SpaceAfterEachValue, true);
    return debug;
}

}}

#endif