glsl.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_GLSL_HPP
#define ZMOL_GLSL_HPP

#include <string>
#include <set>
#include <unordered_map>
#include <memory>
#include <functional>
#include "opengl3.hpp"
#include "noncopyable.hpp"


namespace zmol
{


class shader:
        private noncopyable
{
public:
        typedef std::shared_ptr < shader > sharedptr;

        explicit shader(GLenum const p_type);
        ~shader();

        inline GLuint get_name() const
        {
                return m_name;
        }

        bool compile_and_store(std::string const &p_code);

        std::string get_info_log() const;

protected:
        GLuint m_name;
};




class program:
        private noncopyable
{
public:
        program();
        ~program();

        inline GLuint get_name() const
        {
                return m_name;
        }

        void attach_shader(shader::sharedptr const &p_shader);

        void detach_shader(shader::sharedptr const &p_shader);

        bool link();

        void bind();
        void unbind();

        GLint get_attribute_location(std::string const &p_attribute_name) const;
        GLint get_uniform_location(std::string const &p_uniform_name) const;
        GLuint get_uniform_block_index(std::string const &p_block_name) const;

        std::string get_info_log() const;

protected:
        typedef std::unordered_map < std::string, GLint > locations_type;
        typedef std::unordered_map < std::string, GLuint > indices_type;
        typedef std::set < shader::sharedptr > glsl_shader_set_type;

        GLuint m_name;
        glsl_shader_set_type m_attached_shaders;
        mutable locations_type m_attribute_locations, m_uniform_locations;
        mutable indices_type m_uniform_block_indices;
};


// glUniformBlockBinding
void bind_uniform_block_to_location(program &p_prog, GLuint const p_block_index, GLuint const p_location);





namespace detail
{


typedef std::function < void(std::string const &p_errormsg) > errormsg_callback;


class build_program_impl
{
public:
        explicit build_program_impl(program &p_prog, errormsg_callback const &p_errormsg_callback);
        build_program_impl& operator()(GLenum const p_type, std::string const &p_identifier, std::string const &p_code);
        build_program_impl& operator()(shader::sharedptr const &p_shaderptr);
        void link();
private:
        program &m_prog;
        errormsg_callback m_errormsg_callback;
};


}


detail::build_program_impl build_program(program &p_prog, detail::errormsg_callback const &p_errormsg_callback = detail::errormsg_callback());



}


#endif