#ifndef __GTK_DISPLAY_DRIVER_OPENGL_H
#define __GTK_DISPLAY_DRIVER_OPENGL_H

#include "gtk_s9x.h"
#include "gtk_display_driver.h"

#include <epoxy/gl.h>
#include <epoxy/glx.h>

#include "Cg/CGLCG.h"

#define PBO_FMT_16 0
#define PBO_FMT_24 1
#define PBO_FMT_32 2

#define BUFFER_OFFSET(i)             ((char *) NULL + (i))

#ifdef __BIG_ENDIAN__
/* We have to reverse the bytes on MSB systems. This can be slow */
/* GL_UNSIGNED_INT_8_8_8_8_REV = 0x8367 */
#define PBO_BGRA_NATIVE_ORDER        0x8367
#else
#define PBO_BGRA_NATIVE_ORDER        GL_UNSIGNED_BYTE
#endif
#define PBO_GET_FORMAT(x) (((x) == PBO_FMT_32) ? GL_BGRA : GL_RGB)
#define PBO_GET_PACKING(x) (((x) == PBO_FMT_16) ? GL_UNSIGNED_SHORT_5_6_5 : (((x) == PBO_FMT_24) ? GL_UNSIGNED_BYTE : PBO_BGRA_NATIVE_ORDER))

class S9xOpenGLDisplayDriver : public S9xDisplayDriver
{
    public:
        S9xOpenGLDisplayDriver (Snes9xWindow *window, Snes9xConfig *config);
        void refresh (int width, int height);
        int init (void);
        void deinit (void);
        void clear_buffers (void);
        void update (int width, int height, int yoffset);
        uint16 *get_next_buffer (void);
        uint16 *get_current_buffer (void);
        void push_buffer (uint16 *src);
        void reconfigure (int width, int height);
        static int query_availability (void);

    private:
        int opengl_defaults (void);
        void swap_control (int enable);
        void gl_swap (void);
        int load_pixel_buffer_functions (void);
        int load_shader_functions (void);
        int load_shaders (const char *);
        void update_texture_size (int width, int height);
        int init_glx (void);
        void create_window (int width, int height);
        void resize_window (int width, int height);

        GLint                    texture_width;
        GLint                    texture_height;
        GLfloat                  vertices[8];
        GLfloat                  texcoords[8];
        GLuint                   texmap;
        GLuint                   pbo;
        GLenum                   tex_target;
        GLuint                   program;
        GLuint                   fragment_shader;
        GLuint                   vertex_shader;

        int                      dyn_resizing;
        int                      using_pbos;
        int                      using_shaders;
        int                      initialized;

        int                      using_cg_shaders;
        CGcontext                cg_context;
        CGLCG                    *cg_shader;

        Display                  *display;
        Window                   xwindow;
        Colormap                 xcolormap;
        XVisualInfo              *vi;
        GdkWindow                *gdk_window;
        GLXContext               glx_context;
        int                      output_window_width;
        int                      output_window_height;
};

#endif /* __GTK_DISPLAY_DRIVER_OPENGL_H */