agg_array.h

windows ce 下的画各种b样条曲线

            {
                add(*data);
                ++data;
            }
        }

        void cut_at(unsigned size)
        {
            if(size < m_size) m_size = size;
        }

        unsigned size() const { return m_size; }

        const T& operator [] (unsigned i) const
        {
            return m_blocks[i >> block_shift][i & block_mask];
        }

        T& operator [] (unsigned i)
        {
            return m_blocks[i >> block_shift][i & block_mask];
        }

        const T& at(unsigned i) const
        { 
            return m_blocks[i >> block_shift][i & block_mask];
        }

        T& at(unsigned i) 
        { 
            return m_blocks[i >> block_shift][i & block_mask];
        }

        T value_at(unsigned i) const
        { 
            return m_blocks[i >> block_shift][i & block_mask];
        }

        const T& curr(unsigned idx) const
        {
            return (*this)[idx];
        }

        T& curr(unsigned idx)
        {
            return (*this)[idx];
        }

        const T& prev(unsigned idx) const
        {
            return (*this)[(idx + m_size - 1) % m_size];
        }

        T& prev(unsigned idx)
        {
            return (*this)[(idx + m_size - 1) % m_size];
        }

        const T& next(unsigned idx) const
        {
            return (*this)[(idx + 1) % m_size];
        }

        T& next(unsigned idx)
        {
            return (*this)[(idx + 1) % m_size];
        }

        const T& last() const
        {
            return (*this)[m_size - 1];
        }

        T& last()
        {
            return (*this)[m_size - 1];
        }

        unsigned byte_size() const;
        void serialize(int8u* ptr) const;
        void deserialize(const int8u* data, unsigned byte_size);
        void deserialize(unsigned start, const T& empty_val, 
                         const int8u* data, unsigned byte_size);

        template<class ByteAccessor> 
        void deserialize(ByteAccessor data)
        {
            remove_all();
            unsigned elem_size = data.size() / sizeof(T);

            for(unsigned i = 0; i < elem_size; ++i)
            {
                int8u* ptr = (int8u*)data_ptr();
                for(unsigned j = 0; j < sizeof(T); ++j)
                {
                    *ptr++ = *data;
                    ++data;
                }
                ++m_size;
            }
        }

        template<class ByteAccessor>
        void deserialize(unsigned start, const T& empty_val, ByteAccessor data)
        {
            while(m_size < start)
            {
                add(empty_val);
            }

            unsigned elem_size = data.size() / sizeof(T);
            for(unsigned i = 0; i < elem_size; ++i)
            {
                int8u* ptr;
                if(start + i < m_size)
                {
                    ptr = (int8u*)(&((*this)[start + i]));
                }
                else
                {
                    ptr = (int8u*)data_ptr();
                    ++m_size;
                }
                for(unsigned j = 0; j < sizeof(T); ++j)
                {
                    *ptr++ = *data;
                    ++data;
                }
            }
        }

        const T* block(unsigned nb) const { return m_blocks[nb]; }

    private:
        void allocate_block(unsigned nb);
        T*   data_ptr();

        unsigned        m_size;
        unsigned        m_num_blocks;
        unsigned        m_max_blocks;
        T**             m_blocks;
        unsigned        m_block_ptr_inc;
    };


    //------------------------------------------------------------------------
    template<class T, unsigned S> pod_bvector<T, S>::~pod_bvector()
    {
        if(m_num_blocks)
        {
            T** blk = m_blocks + m_num_blocks - 1;
            while(m_num_blocks--)
            {
                pod_allocator<T>::deallocate(*blk, block_size);
                --blk;
            }
        }
        pod_allocator<T*>::deallocate(m_blocks, m_max_blocks);
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    void pod_bvector<T, S>::free_tail(unsigned size)
    {
        if(size < m_size)
        {
            unsigned nb = (size + block_mask) >> block_shift;
            while(m_num_blocks > nb)
            {
                pod_allocator<T>::deallocate(m_blocks[--m_num_blocks], block_size);
            }
            if(m_num_blocks == 0)
            {
                pod_allocator<T*>::deallocate(m_blocks, m_max_blocks);
                m_blocks = 0;
                m_max_blocks = 0;
            }
            m_size = size;
        }
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> pod_bvector<T, S>::pod_bvector() :
        m_size(0),
        m_num_blocks(0),
        m_max_blocks(0),
        m_blocks(0),
        m_block_ptr_inc(block_size)
    {
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    pod_bvector<T, S>::pod_bvector(unsigned block_ptr_inc) :
        m_size(0),
        m_num_blocks(0),
        m_max_blocks(0),
        m_blocks(0),
        m_block_ptr_inc(block_ptr_inc)
    {
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    pod_bvector<T, S>::pod_bvector(const pod_bvector<T, S>& v) :
        m_size(v.m_size),
        m_num_blocks(v.m_num_blocks),
        m_max_blocks(v.m_max_blocks),
        m_blocks(v.m_max_blocks ? 
                 pod_allocator<T*>::allocate(v.m_max_blocks) : 
                 0),
        m_block_ptr_inc(v.m_block_ptr_inc)
    {
        unsigned i;
        for(i = 0; i < v.m_num_blocks; ++i)
        {
            m_blocks[i] = pod_allocator<T>::allocate(block_size);
            memcpy(m_blocks[i], v.m_blocks[i], block_size * sizeof(T));
        }
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    const pod_bvector<T, S>& 
    pod_bvector<T, S>::operator = (const pod_bvector<T, S>& v)
    {
        unsigned i;
        for(i = m_num_blocks; i < v.m_num_blocks; ++i)
        {
            allocate_block(i);
        }
        for(i = 0; i < v.m_num_blocks; ++i)
        {
            memcpy(m_blocks[i], v.m_blocks[i], block_size * sizeof(T));
        }
        m_size = v.m_size;
        return *this;
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S>
    void pod_bvector<T, S>::allocate_block(unsigned nb)
    {
        if(nb >= m_max_blocks) 
        {
            T** new_blocks = pod_allocator<T*>::allocate(m_max_blocks + m_block_ptr_inc);

            if(m_blocks)
            {
                memcpy(new_blocks, 
                       m_blocks, 
                       m_num_blocks * sizeof(T*));

                pod_allocator<T*>::deallocate(m_blocks, m_max_blocks);
            }
            m_blocks = new_blocks;
            m_max_blocks += m_block_ptr_inc;
        }
        m_blocks[nb] = pod_allocator<T>::allocate(block_size);
        m_num_blocks++;
    }



    //------------------------------------------------------------------------
    template<class T, unsigned S>
    inline T* pod_bvector<T, S>::data_ptr()
    {
        unsigned nb = m_size >> block_shift;
        if(nb >= m_num_blocks)
        {
            allocate_block(nb);
        }
        return m_blocks[nb] + (m_size & block_mask);
    }



    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    inline void pod_bvector<T, S>::add(const T& val)
    {
        *data_ptr() = val;
        ++m_size;
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    inline void pod_bvector<T, S>::remove_last()
    {
        if(m_size) --m_size;
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    void pod_bvector<T, S>::modify_last(const T& val)
    {
        remove_last();
        add(val);
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    int pod_bvector<T, S>::allocate_continuous_block(unsigned num_elements)
    {
        if(num_elements < block_size)
        {
            data_ptr(); // Allocate initial block if necessary
            unsigned rest = block_size - (m_size & block_mask);
            unsigned index;
            if(num_elements <= rest)
            {
                // The rest of the block is good, we can use it
                //-----------------
                index = m_size;
                m_size += num_elements;
                return index;
            }

            // New block
            //---------------
            m_size += rest;
            data_ptr();
            index = m_size;
            m_size += num_elements;
            return index;
        }
        return -1; // Impossible to allocate
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    unsigned pod_bvector<T, S>::byte_size() const
    {
        return m_size * sizeof(T);
    }


    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    void pod_bvector<T, S>::serialize(int8u* ptr) const
    {
        unsigned i;
        for(i = 0; i < m_size; i++)
        {
            memcpy(ptr, &(*this)[i], sizeof(T));
            ptr += sizeof(T);
        }
    }

    //------------------------------------------------------------------------
    template<class T, unsigned S> 
    void pod_bvector<T, S>::deserialize(const int8u* data, unsigned byte_size)
    {
        remove_all();
        byte_size /= sizeof(T);
        for(unsigned i = 0; i < byte_size; ++i)
        {
            T* ptr = data_ptr();
            memcpy(ptr, data, sizeof(T));
            ++m_size;
            data += sizeof(T);
        }
    }


    // Replace or add a number of elements starting from "start" position