buffer_object.hpp

/****************************************************************************

Copyright (c) 2012 Carlos Rafael Giani  ( email: dv xxx AT pseudoterminal xxx DOT xxx org , remove the xxx )

This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must not
   claim that you wrote the original software. If you use this software
   in a product, an acknowledgment in the product documentation would be
   appreciated but is not required.

   2. Altered source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

   3. This notice may not be removed or altered from any source
   distribution.

****************************************************************************/



#ifndef ZMOL_BUFFER_OBJECT_HPP
#define ZMOL_BUFFER_OBJECT_HPP

#include "opengl3.hpp"
#include "noncopyable.hpp"


namespace zmol
{


class buffer_object:
        private noncopyable
{
public:
        explicit buffer_object(GLenum const p_target, GLenum const p_usage);
        ~buffer_object();

        inline GLuint get_name() const
        {
                return m_name;
        }

        inline GLenum get_target() const
        {
                return m_target;
        }

        inline GLenum get_usage() const
        {
                return m_usage;
        }

        void bind();
        void unbind();

        void upload_data(void const *p_data, unsigned long const p_num_bytes);
        void resize(unsigned long const p_num_bytes);

        inline unsigned long get_size() const
        {
                return m_size; // also used in buffer_object_mapping in assert() expressions to catch out-of-bound errors
        }

protected:
        GLuint m_name;
        GLenum m_target, m_usage;
        unsigned long m_size;
};


class buffer_object_mapping:
        private noncopyable
{
public:
        explicit buffer_object_mapping(buffer_object &p_bufobj, GLenum const p_access);
        explicit buffer_object_mapping(buffer_object &p_bufobj, GLenum const p_access, GLintptr const p_offset, GLsizeiptr p_length);
        ~buffer_object_mapping();

        void* get_mapped_pointer();
        void const * get_mapped_pointer() const;

        void flush_subrange(GLintptr const p_offset, GLsizeiptr p_length);
        void flush_entire_range();

private:
        buffer_object &m_bufobj;
        GLvoid *m_mapped_pointer;
        GLintptr m_flush_offset;
        GLsizeiptr m_flush_length;
        bool m_explicit_flush;
};


// glBindBufferBase
void bind_to_indexed_target(buffer_object &p_bufobj, GLenum const p_target, GLuint const p_index);
// glBindBufferRange
void bind_to_indexed_target(buffer_object &p_bufobj, GLenum const p_target, GLuint const p_index, GLintptr const p_offset, GLsizeiptr const p_size);


}


#endif