/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2004 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Atari OSMesa.ldg implementation of SDL OpenGL support */

#ifndef _SDL_ATARIGL_H_
#define _SDL_ATARIGL_H_

#if SDL_VIDEO_OPENGL
#include <GL/osmesa.h>
#endif

#include "../SDL_sysvideo.h"

/* Hidden "this" pointer for the video functions */
#define _THIS   SDL_VideoDevice *this

struct SDL_PrivateGLData
{

    int gl_active;              /* to stop switching drivers while we have a valid context */

    int gl_oldmesa;             /* Old OpenGL support ? */

    int gl_pixelsize;           /* for CopyShadow functions */

    SDL_bool gl_upsidedown;     /* Some implementations draw upside down */

    Uint8 *gl_shadow;           /* Shadow buffer for old implementations */

    /* for unsupported OSMesa buffer formats */
    void (*ConvertSurface) (_THIS, SDL_Surface * surface);

    /* to convert the shadow buffer to the screen format */
    void (*CopyShadow) (_THIS, SDL_Surface * surface);

#if SDL_VIDEO_OPENGL
    OSMesaContext ctx;

    /* OpenGL functions */
    void (*glGetIntegerv) (GLenum pname, GLint * value);
    void (*glFinish) (void);
    void (*glFlush) (void);

    /* osmesa.ldg */
      OSMesaContext (*OSMesaCreateContextExt) (GLenum format, GLint depthBits,
                                               GLint stencilBits,
                                               GLint accumBits,
                                               OSMesaContext sharelist);
    void (*OSMesaDestroyContext) (OSMesaContext ctx);
      GLboolean (*OSMesaMakeCurrent) (OSMesaContext ctx, void *buffer,
                                      GLenum type, GLsizei width,
                                      GLsizei height);
    void (*OSMesaPixelStore) (GLint pname, GLint value);
    void *(*OSMesaGetProcAddress) (const char *funcName);

    /* mesa_gl.ldg, tiny_gl.ldg */
    void *(*OSMesaCreateLDG) (long format, long type, long width,
                              long height);
    void (*OSMesaDestroyLDG) (void);

    /* Info needed to compare existing context with new asked one */
    int width, height;
    GLenum format;
    GLint depth, stencil, accum;
#endif
};

/* Variable names */
#define gl_active		(this->gl_data->gl_active)
#define gl_ctx			(this->gl_data->ctx)
#define gl_oldmesa		(this->gl_data->gl_oldmesa)
#define gl_pixelsize	(this->gl_data->gl_pixelsize)
#define gl_upsidedown	(this->gl_data->gl_upsidedown)
#define gl_shadow		(this->gl_data->gl_shadow)
#define gl_convert		(this->gl_data->ConvertSurface)
#define gl_copyshadow	(this->gl_data->CopyShadow)
#define gl_curformat	(this->gl_data->format)
#define gl_curdepth		(this->gl_data->depth)
#define gl_curstencil	(this->gl_data->stencil)
#define gl_curaccum		(this->gl_data->accum)
#define gl_curwidth		(this->gl_data->width)
#define gl_curheight	(this->gl_data->height)

/* OpenGL functions */
extern int SDL_AtariGL_Init (_THIS, SDL_Surface * current);
extern void SDL_AtariGL_Quit (_THIS, SDL_bool unload);
extern void SDL_AtariGL_InitPointers (_THIS);

extern int SDL_AtariGL_LoadLibrary (_THIS, const char *path);
extern void *SDL_AtariGL_GetProcAddress (_THIS, const char *proc);
extern int SDL_AtariGL_GetAttribute (_THIS, SDL_GLattr attrib, int *value);
extern int SDL_AtariGL_MakeCurrent (_THIS);
extern void SDL_AtariGL_SwapBuffers (_THIS);

#endif /* _SDL_ATARIGL_H_ */
/* vi: set ts=4 sw=4 expandtab: */