MyShader.hpp

#ifndef _SHADER_HPP_
#define _SHADER_HPP_

#include "common.hpp"

// This is a very simple shader class

class MyShader
{
public:

        // Loads shaders from files and compiles them.
        // When path is "hello", the files "hello.frag" & "hello.vert"
        // will be loaded.
        MyShader(const string &path);
        ~MyShader();

        // Bind the shader to the OGL state-machine
        void bind() const
        {
                glUseProgram(_program);
        }

        // Unbind the shader
        void unbind() const
        {
                glUseProgram(0);
        }

        // Query the location of a vertex attribute inside the shader.
        GLint get_attrib_location(const std::string &name) const
        {
                return glGetAttribLocation(_program, name.c_str());
        }

        // Query the location of a uniform variable inside the shader.
        GLint get_uniform_location(const std::string &name) const
        {
                return glGetUniformLocation(_program, name.c_str());
        }

        // Define the name of the variable inside the shader which represents the final color for each fragment.
        void bind_frag_data_location(const std::string &name)
        {
                if(_program > 0)
                {
                        glBindFragDataLocation(_program, 0, name.c_str() );
                        link();
                }
        }

        // Define the name of the variable inside the shader which represents the final color for each fragment.
        void bind_frag_data_location(const std::string &name, const std::string &name2)
        {
                if(_program > 0)
                {
                        glBindFragDataLocation(_program, 0, name.c_str() );
                        glBindFragDataLocation(_program, 1, name2.c_str() );
                        link();
                }
        }

        // A little cast helper.
        // With this you can simply do "if (shader) {...}" to test if a
        // shader has been compiled successfully.
        operator bool ()
        {
                return _success;
        }

public:
        std::string shadername;

private:

        bool _success;

        GLuint _vertex_shader;
        GLuint _geometry_shader;
        GLuint _fragment_shader;
        GLuint _program;

        GLuint compile(GLenum type, const string &source);
        void link (void);

        void shader_log(GLuint shader);
        void program_log(GLuint program);

        bool m_geometry;
};

#endif //#ifndef _SHADER_HPP_