/*

     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

 */

 #ifdef SAVE_RCSID

 static char rcsid =

  "@(#) $Id$";

 #endif

 /* The high-level video driver subsystem */

 #include <stdio.h>

 #include <stdlib.h>

 #include <string.h>

 #include "SDL.h"

 #include "SDL_error.h"

 #include "SDL_video.h"

 #include "SDL_events.h"

 #include "SDL_mutex.h"

 #include "SDL_sysvideo.h"

 #include "SDL_sysevents.h"

 #include "SDL_blit.h"

 #include "SDL_pixels_c.h"

 #include "SDL_events_c.h"

 #include "SDL_cursor_c.h"

 /* Available video drivers */

 static VideoBootStrap *bootstrap[] = {

 #ifdef ENABLE_QUARTZ

 	&QZ_bootstrap,

 #endif

 #ifdef ENABLE_X11

 	&X11_bootstrap,

 #endif

 #ifdef ENABLE_DGA

 	&DGA_bootstrap,

 #endif

 #ifdef ENABLE_NANOX

 	&NX_bootstrap,

 #endif

 #ifdef ENABLE_IPOD

 	&iPod_bootstrap,

 #endif

 #ifdef ENABLE_QTOPIA

 	&Qtopia_bootstrap,

 #endif

 #ifdef ENABLE_WSCONS

 	&WSCONS_bootstrap,

 #endif

 #ifdef ENABLE_FBCON

 	&FBCON_bootstrap,

 #endif

 #ifdef ENABLE_DIRECTFB

 	&DirectFB_bootstrap,

 #endif

 #ifdef ENABLE_PS2GS

 	&PS2GS_bootstrap,

 #endif

 #ifdef ENABLE_GGI

 	&GGI_bootstrap,

 #endif

 #ifdef ENABLE_VGL

 	&VGL_bootstrap,

 #endif

 #ifdef ENABLE_SVGALIB

 	&SVGALIB_bootstrap,

 #endif

 #ifdef ENABLE_AALIB

 	&AALIB_bootstrap,

 #endif

 #ifdef ENABLE_GAPI

 	&GAPI_bootstrap,

 #endif

 #ifdef ENABLE_WINDIB

 	&WINDIB_bootstrap,

 #endif

 #ifdef ENABLE_DIRECTX

 	&DIRECTX_bootstrap,

 #endif

 #ifdef ENABLE_BWINDOW

 	&BWINDOW_bootstrap,

 #endif

 #ifdef ENABLE_TOOLBOX

 	&TOOLBOX_bootstrap,

 #endif

 #ifdef ENABLE_DRAWSPROCKET

 	&DSp_bootstrap,

 #endif

 #ifdef ENABLE_CYBERGRAPHICS

 	&CGX_bootstrap,

 #endif

 #ifdef ENABLE_PHOTON

 	&ph_bootstrap,

 #endif

 #ifdef ENABLE_EPOC

 	&EPOC_bootstrap,

 #endif

 #ifdef ENABLE_XBIOS

 	&XBIOS_bootstrap,

 #endif

 #ifdef ENABLE_GEM

 	&GEM_bootstrap,

 #endif

 #ifdef ENABLE_PICOGUI

 	&PG_bootstrap,

 #endif

 #ifdef ENABLE_DC

 	&DC_bootstrap,

 #endif

 #ifdef ENABLE_RISCOS

 	&RISCOS_bootstrap,

 #endif

 #ifdef __OS2__

 	&OS2FSLib_bootstrap,

 #endif

 #ifdef ENABLE_DUMMYVIDEO

 	&DUMMY_bootstrap,

 #endif

 	NULL

 };

 SDL_VideoDevice *current_video = NULL;

 /* Various local functions */

 int SDL_VideoInit(const char *driver_name, Uint32 flags);

 void SDL_VideoQuit(void);

 void SDL_GL_UpdateRectsLock(SDL_VideoDevice* this, int numrects, SDL_Rect* rects);

 static SDL_GrabMode SDL_WM_GrabInputOff(void);

 #ifdef HAVE_OPENGL

 static int lock_count = 0;

 #endif

 /*

  * Initialize the video and event subsystems -- determine native pixel format

  */

 int SDL_VideoInit (const char *driver_name, Uint32 flags)

 {

 	SDL_VideoDevice *video;

 	int index;

 	int i;

 	SDL_PixelFormat vformat;

 	Uint32 video_flags;

 	/* Toggle the event thread flags, based on OS requirements */

 #if defined(MUST_THREAD_EVENTS)

 	flags |= SDL_INIT_EVENTTHREAD;

 #elif defined(CANT_THREAD_EVENTS)

 	if ( (flags & SDL_INIT_EVENTTHREAD) == SDL_INIT_EVENTTHREAD ) {

 		SDL_SetError("OS doesn't support threaded events");

 		return(-1);

 	}

 #endif

 	/* Check to make sure we don't overwrite 'current_video' */

 	if ( current_video != NULL ) {

 		SDL_VideoQuit();

 	}

 	/* Select the proper video driver */

 	index = 0;

 	video = NULL;

 	if ( driver_name != NULL ) {

 #if 0	/* This will be replaced with a better driver selection API */

 		if ( strrchr(driver_name, ':') != NULL ) {

 			index = atoi(strrchr(driver_name, ':')+1);

 		}

 #endif

 		for ( i=0; bootstrap[i]; ++i ) {

 			if ( strncmp(bootstrap[i]->name, driver_name,

 			             strlen(bootstrap[i]->name)) == 0 ) {

 				if ( bootstrap[i]->available() ) {

 					video = bootstrap[i]->create(index);

 					break;

 				}

 			}

 		}

 	} else {

 		for ( i=0; bootstrap[i]; ++i ) {

 			if ( bootstrap[i]->available() ) {

 				video = bootstrap[i]->create(index);

 				if ( video != NULL ) {

 					break;

 				}

 			}

 		}

 	}

 	if ( video == NULL ) {

 		SDL_SetError("No available video device");

 		return(-1);

 	}

 	current_video = video;

 	current_video->name = bootstrap[i]->name;

 	/* Do some basic variable initialization */

 	video->screen = NULL;

 	video->shadow = NULL;

 	video->visible = NULL;

 	video->physpal = NULL;

 	video->gammacols = NULL;

 	video->gamma = NULL;

 	video->wm_title = NULL;

 	video->wm_icon  = NULL;

 	video->offset_x = 0;

 	video->offset_y = 0;

 	memset(&video->info, 0, (sizeof video->info));

 	video->displayformatalphapixel = NULL;

 	/* Set some very sane GL defaults */

 	video->gl_config.driver_loaded = 0;

 	video->gl_config.dll_handle = NULL;

 	video->gl_config.red_size = 5;

 #if 1 /* This seems to work on more video cards, as a default */

 	video->gl_config.green_size = 5;

 #else

 	video->gl_config.green_size = 6;

 #endif

 	video->gl_config.blue_size = 5;

 	video->gl_config.alpha_size = 0;

 	video->gl_config.buffer_size = 0;

 	video->gl_config.depth_size = 16;

 	video->gl_config.stencil_size = 0;

 	video->gl_config.double_buffer = 1;

 	video->gl_config.accum_red_size = 0;

 	video->gl_config.accum_green_size = 0;

 	video->gl_config.accum_blue_size = 0;

 	video->gl_config.accum_alpha_size = 0;

 	video->gl_config.stereo = 0;

 	video->gl_config.multisamplebuffers = 0;

 	video->gl_config.multisamplesamples = 0;

 	/* Initialize the video subsystem */

 	memset(&vformat, 0, sizeof(vformat));

 	if ( video->VideoInit(video, &vformat) < 0 ) {

 		SDL_VideoQuit();

 		return(-1);

 	}

 	/* Create a zero sized video surface of the appropriate format */

 	video_flags = SDL_SWSURFACE;

 	SDL_VideoSurface = SDL_CreateRGBSurface(video_flags, 0, 0,

 				vformat.BitsPerPixel,

 				vformat.Rmask, vformat.Gmask, vformat.Bmask, 0);

 	if ( SDL_VideoSurface == NULL ) {

 		SDL_VideoQuit();

 		return(-1);

 	}

 	SDL_PublicSurface = NULL;	/* Until SDL_SetVideoMode() */

 #if 0 /* Don't change the current palette - may be used by other programs.

        * The application can't do anything with the display surface until

        * a video mode has been set anyway. :)

        */

 	/* If we have a palettized surface, create a default palette */

 	if ( SDL_VideoSurface->format->palette ) {

 		SDL_PixelFormat *vf = SDL_VideoSurface->format;

 		SDL_DitherColors(vf->palette->colors, vf->BitsPerPixel);

 		video->SetColors(video,

 				 0, vf->palette->ncolors, vf->palette->colors);

 	}

 #endif

 	video->info.vfmt = SDL_VideoSurface->format;

 	/* Start the event loop */

 	if ( SDL_StartEventLoop(flags) < 0 ) {

 		SDL_VideoQuit();

 		return(-1);

 	}

 	SDL_CursorInit(flags & SDL_INIT_EVENTTHREAD);

 	/* We're ready to go! */

 	return(0);

 }

 char *SDL_VideoDriverName(char *namebuf, int maxlen)

 {

 	if ( current_video != NULL ) {

 		strncpy(namebuf, current_video->name, maxlen-1);

 		namebuf[maxlen-1] = '\0';

 		return(namebuf);

 	}

 	return(NULL);

 }

 /*

  * Get the current display surface

  */

 SDL_Surface *SDL_GetVideoSurface(void)

 {

 	SDL_Surface *visible;

 	visible = NULL;

 	if ( current_video ) {

 		visible = current_video->visible;

 	}

 	return(visible);

 }

 /*

  * Get the current information about the video hardware

  */

 const SDL_VideoInfo *SDL_GetVideoInfo(void)

 {

 	const SDL_VideoInfo *info;

 	info = NULL;

 	if ( current_video ) {

 		info = &current_video->info;

 	}

 	return(info);

 }

 /*

  * Return a pointer to an array of available screen dimensions for the

  * given format, sorted largest to smallest.  Returns NULL if there are

  * no dimensions available for a particular format, or (SDL_Rect **)-1

  * if any dimension is okay for the given format.  If 'format' is NULL,

  * the mode list will be for the format given by SDL_GetVideoInfo()->vfmt

  */

 SDL_Rect ** SDL_ListModes (SDL_PixelFormat *format, Uint32 flags)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	SDL_Rect **modes;

 	modes = NULL;

 	if ( SDL_VideoSurface ) {

 		if ( format == NULL ) {

 			format = SDL_VideoSurface->format;

 		}

 		modes = video->ListModes(this, format, flags);

 	}

 	return(modes);

 }

 /*

  * Check to see if a particular video mode is supported.

  * It returns 0 if the requested mode is not supported under any bit depth,

  * or returns the bits-per-pixel of the closest available mode with the

  * given width and height.  If this bits-per-pixel is different from the

  * one used when setting the video mode, SDL_SetVideoMode() will succeed,

  * but will emulate the requested bits-per-pixel with a shadow surface.

  */

 static Uint8 SDL_closest_depths[4][8] = {

 	/* 8 bit closest depth ordering */

 	{ 0, 8, 16, 15, 32, 24, 0, 0 },

 	/* 15,16 bit closest depth ordering */

 	{ 0, 16, 15, 32, 24, 8, 0, 0 },

 	/* 24 bit closest depth ordering */

 	{ 0, 24, 32, 16, 15, 8, 0, 0 },

 	/* 32 bit closest depth ordering */

 	{ 0, 32, 16, 15, 24, 8, 0, 0 }

 };

 #ifdef macintosh /* MPW optimization bug? */

 #define NEGATIVE_ONE 0xFFFFFFFF

 #else

 #define NEGATIVE_ONE -1

 #endif

 int SDL_VideoModeOK (int width, int height, int bpp, Uint32 flags)

 {

 	int table, b, i;

 	int supported;

 	SDL_PixelFormat format;

 	SDL_Rect **sizes;

 	/* Currently 1 and 4 bpp are not supported */

 	if ( bpp < 8 || bpp > 32 ) {

 		return(0);

 	}

 	if ( (width <= 0) || (height <= 0) ) {

 		return(0);

 	}

 	/* Search through the list valid of modes */

 	memset(&format, 0, sizeof(format));

 	supported = 0;

 	table = ((bpp+7)/8)-1;

 	SDL_closest_depths[table][0] = bpp;

 	SDL_closest_depths[table][7] = 0;

 	for ( b = 0; !supported && SDL_closest_depths[table][b]; ++b ) {

 		format.BitsPerPixel = SDL_closest_depths[table][b];

 		sizes = SDL_ListModes(&format, flags);

 		if ( sizes == (SDL_Rect **)0 ) {

 			/* No sizes supported at this bit-depth */

 			continue;

 		} else 

 		if (sizes == (SDL_Rect **)NEGATIVE_ONE) {

 			/* Any size supported at this bit-depth */

 			supported = 1;

 			continue;

 		} else if (current_video->handles_any_size) {

 			/* Driver can center a smaller surface to simulate fullscreen */

 			for ( i=0; sizes[i]; ++i ) {

 				if ((sizes[i]->w >= width) && (sizes[i]->h >= height)) {

 					supported = 1; /* this mode can fit the centered window. */

 					break;

 				}

 			}

 		} else

 		for ( i=0; sizes[i]; ++i ) {

 			if ((sizes[i]->w == width) && (sizes[i]->h == height)) {

 				supported = 1;

 				break;

 			}

 		}

 	}

 	if ( supported ) {

 		--b;

 		return(SDL_closest_depths[table][b]);

 	} else {

 		return(0);

 	}

 }

 /*

  * Get the closest non-emulated video mode to the one requested

  */

 static int SDL_GetVideoMode (int *w, int *h, int *BitsPerPixel, Uint32 flags)

 {

 	int table, b, i;

 	int supported;

 	int native_bpp;

 	SDL_PixelFormat format;

 	SDL_Rect **sizes;

 	/* Check parameters */

 	if ( *BitsPerPixel < 8 || *BitsPerPixel > 32 ) {

 		SDL_SetError("Invalid bits per pixel (range is {8...32})");

 		return(0);

 	}

 	if ((*w <= 0) || (*h <= 0)) {

 		SDL_SetError("Invalid width or height");

 		return(0);

 	}

 	/* Try the original video mode, get the closest depth */

 	native_bpp = SDL_VideoModeOK(*w, *h, *BitsPerPixel, flags);

 	if ( native_bpp == *BitsPerPixel ) {

 		return(1);

 	}

 	if ( native_bpp > 0 ) {

 		*BitsPerPixel = native_bpp;

 		return(1);

 	}

 	/* No exact size match at any depth, look for closest match */

 	memset(&format, 0, sizeof(format));

 	supported = 0;

 	table = ((*BitsPerPixel+7)/8)-1;

 	SDL_closest_depths[table][0] = *BitsPerPixel;

 	SDL_closest_depths[table][7] = SDL_VideoSurface->format->BitsPerPixel;

 	for ( b = 0; !supported && SDL_closest_depths[table][b]; ++b ) {

 		int best;

 		format.BitsPerPixel = SDL_closest_depths[table][b];

 		sizes = SDL_ListModes(&format, flags);

 		if ( sizes == (SDL_Rect **)0 ) {

 			/* No sizes supported at this bit-depth */

 			continue;

 		}

 		best=0;

 		for ( i=0; sizes[i]; ++i ) {

 			/* Mode with both dimensions bigger or equal than asked ? */

 			if ((sizes[i]->w >= *w) && (sizes[i]->h >= *h)) {

 				/* Mode with any dimension smaller or equal than current best ? */

 				if ((sizes[i]->w <= sizes[best]->w) || (sizes[i]->h <= sizes[best]->h)) {

 					/* Now choose the mode that has less pixels */

 					if ((sizes[i]->w * sizes[i]->h) <= (sizes[best]->w * sizes[best]->h)) {

 						best=i;

 						supported = 1;

 					}

 				}

 			}

 		}

 		if (supported) {

 			*w=sizes[best]->w;

 			*h=sizes[best]->h;

 			*BitsPerPixel = SDL_closest_depths[table][b];

 		}

 	}

 	if ( ! supported ) {

 		SDL_SetError("No video mode large enough for %dx%d", *w, *h);

 	}

 	return(supported);

 }

 /* This should probably go somewhere else -- like SDL_surface.c */

 static void SDL_ClearSurface(SDL_Surface *surface)

 {

 	Uint32 black;

 	black = SDL_MapRGB(surface->format, 0, 0, 0);

 	SDL_FillRect(surface, NULL, black);

 	if ((surface->flags&SDL_HWSURFACE) && (surface->flags&SDL_DOUBLEBUF)) {

 		SDL_Flip(surface);

 		SDL_FillRect(surface, NULL, black);

 	}

 	SDL_Flip(surface);

 }

 /*

  * Create a shadow surface suitable for fooling the app. :-)

  */

 static void SDL_CreateShadowSurface(int depth)

 {

 	Uint32 Rmask, Gmask, Bmask;

 	/* Allocate the shadow surface */

 	if ( depth == (SDL_VideoSurface->format)->BitsPerPixel ) {

 		Rmask = (SDL_VideoSurface->format)->Rmask;

 		Gmask = (SDL_VideoSurface->format)->Gmask;

 		Bmask = (SDL_VideoSurface->format)->Bmask;

 	} else {

 		Rmask = Gmask = Bmask = 0;

 	}

 	SDL_ShadowSurface = SDL_CreateRGBSurface(SDL_SWSURFACE,

 				SDL_VideoSurface->w, SDL_VideoSurface->h,

 						depth, Rmask, Gmask, Bmask, 0);

 	if ( SDL_ShadowSurface == NULL ) {

 		return;

 	}

 	/* 8-bit shadow surfaces report that they have exclusive palette */

 	if ( SDL_ShadowSurface->format->palette ) {

 		SDL_ShadowSurface->flags |= SDL_HWPALETTE;

 		if ( depth == (SDL_VideoSurface->format)->BitsPerPixel ) {

 			memcpy(SDL_ShadowSurface->format->palette->colors,

 				SDL_VideoSurface->format->palette->colors,

 				SDL_VideoSurface->format->palette->ncolors*

 							sizeof(SDL_Color));

 		} else {

 			SDL_DitherColors(

 			SDL_ShadowSurface->format->palette->colors, depth);

 		}

 	}

 	/* If the video surface is resizable, the shadow should say so */

 	if ( (SDL_VideoSurface->flags & SDL_RESIZABLE) == SDL_RESIZABLE ) {

 		SDL_ShadowSurface->flags |= SDL_RESIZABLE;

 	}

 	/* If the video surface has no frame, the shadow should say so */

 	if ( (SDL_VideoSurface->flags & SDL_NOFRAME) == SDL_NOFRAME ) {

 		SDL_ShadowSurface->flags |= SDL_NOFRAME;

 	}

 	/* If the video surface is fullscreen, the shadow should say so */

 	if ( (SDL_VideoSurface->flags & SDL_FULLSCREEN) == SDL_FULLSCREEN ) {

 		SDL_ShadowSurface->flags |= SDL_FULLSCREEN;

 	}

 	/* If the video surface is flippable, the shadow should say so */

 	if ( (SDL_VideoSurface->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) {

 		SDL_ShadowSurface->flags |= SDL_DOUBLEBUF;

 	}

 	return;

 }

 #ifdef __QNXNTO__

     #include <sys/neutrino.h>

 #endif /* __QNXNTO__ */

 /*

  * Set the requested video mode, allocating a shadow buffer if necessary.

  */

 SDL_Surface * SDL_SetVideoMode (int width, int height, int bpp, Uint32 flags)

 {

 	SDL_VideoDevice *video, *this;

 	SDL_Surface *prev_mode, *mode;

 	int video_w;

 	int video_h;

 	int video_bpp;

 	int is_opengl;

 	SDL_GrabMode saved_grab;

 	/* Start up the video driver, if necessary..

 	   WARNING: This is the only function protected this way!

 	 */

 	if ( ! current_video ) {

 		if ( SDL_Init(SDL_INIT_VIDEO|SDL_INIT_NOPARACHUTE) < 0 ) {

 			return(NULL);

 		}

 	}

 	this = video = current_video;

 	/* Default to the current video bpp */

 	if ( bpp == 0 ) {

 		flags |= SDL_ANYFORMAT;

 		bpp = SDL_VideoSurface->format->BitsPerPixel;

 	}

 	/* Get a good video mode, the closest one possible */

 	video_w = width;

 	video_h = height;

 	video_bpp = bpp;

 	if ( ! SDL_GetVideoMode(&video_w, &video_h, &video_bpp, flags) ) {

 		return(NULL);

 	}

 	/* Check the requested flags */

 	/* There's no palette in > 8 bits-per-pixel mode */

 	if ( video_bpp > 8 ) {

 		flags &= ~SDL_HWPALETTE;

 	}

 #if 0

 	if ( (flags&SDL_FULLSCREEN) != SDL_FULLSCREEN ) {

 		/* There's no windowed double-buffering */

 		flags &= ~SDL_DOUBLEBUF;

 	}

 #endif

 	if ( (flags&SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) {

 		/* Use hardware surfaces when double-buffering */

 		flags |= SDL_HWSURFACE;

 	}

 	is_opengl = ( ( flags & SDL_OPENGL ) == SDL_OPENGL );

 	if ( is_opengl ) {

 		/* These flags are for 2D video modes only */

 		flags &= ~(SDL_HWSURFACE|SDL_DOUBLEBUF);

 	}

 	/* Reset the keyboard here so event callbacks can run */

 	SDL_ResetKeyboard();

 	SDL_ResetMouse();

 	/* Clean up any previous video mode */

 	if ( SDL_PublicSurface != NULL ) {

 		SDL_PublicSurface = NULL;

 	}

 	if ( SDL_ShadowSurface != NULL ) {

 		SDL_Surface *ready_to_go;

 		ready_to_go = SDL_ShadowSurface;

 		SDL_ShadowSurface = NULL;

 		SDL_FreeSurface(ready_to_go);

 	}

 	if ( video->physpal ) {

 		free(video->physpal->colors);

 		free(video->physpal);

 		video->physpal = NULL;

 	}

 	if( video->gammacols) {

 		free(video->gammacols);

 		video->gammacols = NULL;

 	}

 	/* Save the previous grab state and turn off grab for mode switch */

 	saved_grab = SDL_WM_GrabInputOff();

 	/* Try to set the video mode, along with offset and clipping */

 	prev_mode = SDL_VideoSurface;

 	SDL_LockCursor();

 	SDL_VideoSurface = NULL;	/* In case it's freed by driver */

 	mode = video->SetVideoMode(this, prev_mode,video_w,video_h,video_bpp,flags);

 	if ( mode ) { /* Prevent resize events from mode change */

           /* But not on OS/2 */

 #ifndef __OS2__

 	    SDL_PrivateResize(mode->w, mode->h);

 #endif

 	    /* Sam - If we asked for OpenGL mode, and didn't get it, fail */

 	    if ( is_opengl && !(mode->flags & SDL_OPENGL) ) {

 		mode = NULL;

 		SDL_SetError("OpenGL not available");

 	    }

 	}

 	/*

 	 * rcg11292000

 	 * If you try to set an SDL_OPENGL surface, and fail to find a

 	 * matching  visual, then the next call to SDL_SetVideoMode()

 	 * will segfault, since  we no longer point to a dummy surface,

 	 * but rather NULL.

 	 * Sam 11/29/00

 	 * WARNING, we need to make sure that the previous mode hasn't

 	 * already been freed by the video driver.  What do we do in

 	 * that case?  Should we call SDL_VideoInit() again?

 	 */

 	SDL_VideoSurface = (mode != NULL) ? mode : prev_mode;

 	if ( (mode != NULL) && (!is_opengl) ) {

 		/* Sanity check */

 		if ( (mode->w < width) || (mode->h < height) ) {

 			SDL_SetError("Video mode smaller than requested");

 			return(NULL);

 		}

 		/* If we have a palettized surface, create a default palette */

 		if ( mode->format->palette ) {

 			SDL_PixelFormat *vf = mode->format;

 			SDL_DitherColors(vf->palette->colors, vf->BitsPerPixel);

 			video->SetColors(this, 0, vf->palette->ncolors,

 			                           vf->palette->colors);

 		}

 		/* Clear the surface to black */

 		video->offset_x = 0;

 		video->offset_y = 0;

 		mode->offset = 0;

 		SDL_SetClipRect(mode, NULL);

 		SDL_ClearSurface(mode);

 		/* Now adjust the offsets to match the desired mode */

 		video->offset_x = (mode->w-width)/2;

 		video->offset_y = (mode->h-height)/2;

 		mode->offset = video->offset_y*mode->pitch +

 				video->offset_x*mode->format->BytesPerPixel;

 #ifdef DEBUG_VIDEO

   fprintf(stderr,

 	"Requested mode: %dx%dx%d, obtained mode %dx%dx%d (offset %d)\n",

 		width, height, bpp,

 		mode->w, mode->h, mode->format->BitsPerPixel, mode->offset);

 #endif

 		mode->w = width;

 		mode->h = height;

 		SDL_SetClipRect(mode, NULL);

 	}

 	SDL_ResetCursor();

 	SDL_UnlockCursor();

 	/* If we failed setting a video mode, return NULL... (Uh Oh!) */

 	if ( mode == NULL ) {

 		return(NULL);

 	}

 	/* If there is no window manager, set the SDL_NOFRAME flag */

 	if ( ! video->info.wm_available ) {

 		mode->flags |= SDL_NOFRAME;

 	}

 	/* Reset the mouse cursor and grab for new video mode */

 	SDL_SetCursor(NULL);

 	if ( video->UpdateMouse ) {

 		video->UpdateMouse(this);

 	}

 	SDL_WM_GrabInput(saved_grab);

 	SDL_GetRelativeMouseState(NULL, NULL); /* Clear first large delta */

 #ifdef HAVE_OPENGL

 	/* Load GL symbols (before MakeCurrent, where we need glGetString). */

 	if ( flags & (SDL_OPENGL | SDL_OPENGLBLIT) ) {

 #if defined(__QNXNTO__) && (_NTO_VERSION < 630)

 #define __SDL_NOGETPROCADDR__

 #elif defined(__MINT__)

 #define __SDL_NOGETPROCADDR__

 #endif

 #ifdef __SDL_NOGETPROCADDR__

     #define SDL_PROC(ret,func,params) video->func=func;

 #else

     #define SDL_PROC(ret,func,params) \

     do { \

         video->func = SDL_GL_GetProcAddress(#func); \

         if ( ! video->func ) { \

             SDL_SetError("Couldn't load GL function %s: %s\n", #func, SDL_GetError()); \

         return(NULL); \

         } \

     } while ( 0 );

 #endif /* __SDL_NOGETPROCADDR__ */

 #include "SDL_glfuncs.h"

 #undef SDL_PROC	

 	}

 #endif /* HAVE_OPENGL */

 	/* If we're running OpenGL, make the context current */

 	if ( (video->screen->flags & SDL_OPENGL) &&

 	      video->GL_MakeCurrent ) {

 		if ( video->GL_MakeCurrent(this) < 0 ) {

 			return(NULL);

 		}

 	}

 	/* Set up a fake SDL surface for OpenGL "blitting" */

 	if ( (flags & SDL_OPENGLBLIT) == SDL_OPENGLBLIT ) {

 		/* Load GL functions for performing the texture updates */

 #ifdef HAVE_OPENGL

 		/* Create a software surface for blitting */

 #ifdef GL_VERSION_1_2

 		/* If the implementation either supports the packed pixels

 		   extension, or implements the core OpenGL 1.2 API, it will

 		   support the GL_UNSIGNED_SHORT_5_6_5 texture format.

 		 */

 		if ( (bpp == 16) &&

 		     (strstr((const char *)video->glGetString(GL_EXTENSIONS), "GL_EXT_packed_pixels") ||

 		     (atof((const char *)video->glGetString(GL_VERSION)) >= 1.2f))

 		   ) {

 			video->is_32bit = 0;

 			SDL_VideoSurface = SDL_CreateRGBSurface(

 				flags, 

 				width, 

 				height,  

 				16,

 				31 << 11,

 				63 << 5,

 				31,

 				0

 				);

 		}

 		else

 #endif /* OpenGL 1.2 */

 		{

 			video->is_32bit = 1;

 			SDL_VideoSurface = SDL_CreateRGBSurface(

 				flags, 

 				width, 

 				height, 

 				32, 

 #if SDL_BYTEORDER == SDL_LIL_ENDIAN

 				0x000000FF,

 				0x0000FF00,

 				0x00FF0000,

 				0xFF000000

 #else

 				0xFF000000,

 				0x00FF0000,

 				0x0000FF00,

 				0x000000FF

 #endif

 				);

 		}

 		if ( ! SDL_VideoSurface ) {

 			return(NULL);

 		}

 		SDL_VideoSurface->flags = mode->flags | SDL_OPENGLBLIT;

 		/* Free the original video mode surface (is this safe?) */

 		SDL_FreeSurface(mode);

 		/* Set the surface completely opaque & white by default */

 		memset( SDL_VideoSurface->pixels, 255, SDL_VideoSurface->h * SDL_VideoSurface->pitch );

 		video->glGenTextures( 1, &video->texture );

 		video->glBindTexture( GL_TEXTURE_2D, video->texture );

 		video->glTexImage2D(

 			GL_TEXTURE_2D,

 			0,

 			video->is_32bit ? GL_RGBA : GL_RGB,

 			256,

 			256,

 			0,

 			video->is_32bit ? GL_RGBA : GL_RGB,

 #ifdef GL_VERSION_1_2

 			video->is_32bit ? GL_UNSIGNED_BYTE : GL_UNSIGNED_SHORT_5_6_5,

 #else

 			GL_UNSIGNED_BYTE,

 #endif

 			NULL);

 		video->UpdateRects = SDL_GL_UpdateRectsLock;

 #else

 		SDL_SetError("Somebody forgot to #define HAVE_OPENGL");

 		return(NULL);

 #endif

 	}

 	/* Create a shadow surface if necessary */

 	/* There are three conditions under which we create a shadow surface:

 		1.  We need a particular bits-per-pixel that we didn't get.

 		2.  We need a hardware palette and didn't get one.

 		3.  We need a software surface and got a hardware surface.

 	*/

 	if ( !(SDL_VideoSurface->flags & SDL_OPENGL) &&

 	     (

 	     (  !(flags&SDL_ANYFORMAT) &&

 			(SDL_VideoSurface->format->BitsPerPixel != bpp)) ||

 	     (   (flags&SDL_HWPALETTE) && 

 				!(SDL_VideoSurface->flags&SDL_HWPALETTE)) ||

 		/* If the surface is in hardware, video writes are visible

 		   as soon as they are performed, so we need to buffer them

 		 */

 	     (   ((flags&SDL_HWSURFACE) == SDL_SWSURFACE) &&

 				(SDL_VideoSurface->flags&SDL_HWSURFACE)) ||

 	     (   (flags&SDL_DOUBLEBUF) &&

 				(SDL_VideoSurface->flags&SDL_HWSURFACE) &&

 				!(SDL_VideoSurface->flags&SDL_DOUBLEBUF))

 	     ) ) {

 		SDL_CreateShadowSurface(bpp);

 		if ( SDL_ShadowSurface == NULL ) {

 			SDL_SetError("Couldn't create shadow surface");

 			return(NULL);

 		}

 		SDL_PublicSurface = SDL_ShadowSurface;

 	} else {

 		SDL_PublicSurface = SDL_VideoSurface;

 	}

 	video->info.vfmt = SDL_VideoSurface->format;

 	/* We're done! */

 	return(SDL_PublicSurface);

 }

 /* 

  * Convert a surface into the video pixel format.

  */

 SDL_Surface * SDL_DisplayFormat (SDL_Surface *surface)

 {

 	Uint32 flags;

 	if ( ! SDL_PublicSurface ) {

 		SDL_SetError("No video mode has been set");

 		return(NULL);

 	}

 	/* Set the flags appropriate for copying to display surface */

 	if (((SDL_PublicSurface->flags&SDL_HWSURFACE) == SDL_HWSURFACE) && current_video->info.blit_hw)

 		flags = SDL_HWSURFACE;

 	else 

 		flags = SDL_SWSURFACE;

 #ifdef AUTORLE_DISPLAYFORMAT

 	flags |= (surface->flags & (SDL_SRCCOLORKEY|SDL_SRCALPHA));

 	flags |= SDL_RLEACCELOK;

 #else

 	flags |= surface->flags & (SDL_SRCCOLORKEY|SDL_SRCALPHA|SDL_RLEACCELOK);

 #endif

 	return(SDL_ConvertSurface(surface, SDL_PublicSurface->format, flags));

 }

 /*

  * Convert a surface into a format that's suitable for blitting to

  * the screen, but including an alpha channel.

  */

 SDL_Surface *SDL_DisplayFormatAlpha(SDL_Surface *surface)

 {

 	SDL_PixelFormat *vf;

 	SDL_PixelFormat *format;

 	SDL_Surface *converted;

 	Uint32 flags;

 	/* default to ARGB8888 */

 	Uint32 amask = 0xff000000;

 	Uint32 rmask = 0x00ff0000;

 	Uint32 gmask = 0x0000ff00;

 	Uint32 bmask = 0x000000ff;

 	if ( ! SDL_PublicSurface ) {

 		SDL_SetError("No video mode has been set");

 		return(NULL);

 	}

 	vf = SDL_PublicSurface->format;

 	switch(vf->BytesPerPixel) {

 	    case 2:

 		/* For XGY5[56]5, use, AXGY8888, where {X, Y} = {R, B}.

 		   For anything else (like ARGB4444) it doesn't matter

 		   since we have no special code for it anyway */

 		if ( (vf->Rmask == 0x1f) &&

 		     (vf->Bmask == 0xf800 || vf->Bmask == 0x7c00)) {

 			rmask = 0xff;

 			bmask = 0xff0000;

 		}

 		break;

 	    case 3:

 	    case 4:

 		/* Keep the video format, as long as the high 8 bits are

 		   unused or alpha */

 		if ( (vf->Rmask == 0xff) && (vf->Bmask == 0xff0000) ) {

 			rmask = 0xff;

 			bmask = 0xff0000;

 		}

 		break;

 	    default:

 		/* We have no other optimised formats right now. When/if a new

 		   optimised alpha format is written, add the converter here */

 		break;

 	}

 	format = SDL_AllocFormat(32, rmask, gmask, bmask, amask);

 	flags = SDL_PublicSurface->flags & SDL_HWSURFACE;

 	flags |= surface->flags & (SDL_SRCALPHA | SDL_RLEACCELOK);

 	converted = SDL_ConvertSurface(surface, format, flags);

 	SDL_FreeFormat(format);

 	return(converted);

 }

 /*

  * Update a specific portion of the physical screen

  */

 void SDL_UpdateRect(SDL_Surface *screen, Sint32 x, Sint32 y, Uint32 w, Uint32 h)

 {

 	if ( screen ) {

 		SDL_Rect rect;

 		/* Perform some checking */

 		if ( w == 0 )

 			w = screen->w;

 		if ( h == 0 )

 			h = screen->h;

 		if ( (int)(x+w) > screen->w )

 			return;

 		if ( (int)(y+h) > screen->h )

 			return;

 		/* Fill the rectangle */

 		rect.x = x;

 		rect.y = y;

 		rect.w = w;

 		rect.h = h;

 		SDL_UpdateRects(screen, 1, &rect);

 	}

 }

 void SDL_UpdateRects (SDL_Surface *screen, int numrects, SDL_Rect *rects)

 {

 	int i;

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this = current_video;

 	if ( screen == SDL_ShadowSurface ) {

 		/* Blit the shadow surface using saved mapping */

 		SDL_Palette *pal = screen->format->palette;

 		SDL_Color *saved_colors = NULL;

 		if ( pal && !(SDL_VideoSurface->flags & SDL_HWPALETTE) ) {

 			/* simulated 8bpp, use correct physical palette */

 			saved_colors = pal->colors;

 			if ( video->gammacols ) {

 				/* gamma-corrected palette */

 				pal->colors = video->gammacols;

 			} else if ( video->physpal ) {

 				/* physical palette different from logical */

 				pal->colors = video->physpal->colors;

 			}

 		}

 		if ( SHOULD_DRAWCURSOR(SDL_cursorstate) ) {

 			SDL_LockCursor();

 			SDL_DrawCursor(SDL_ShadowSurface);

 			for ( i=0; i<numrects; ++i ) {

 				SDL_LowerBlit(SDL_ShadowSurface, &rects[i], 

 						SDL_VideoSurface, &rects[i]);

 			}

 			SDL_EraseCursor(SDL_ShadowSurface);

 			SDL_UnlockCursor();

 		} else {

 			for ( i=0; i<numrects; ++i ) {

 				SDL_LowerBlit(SDL_ShadowSurface, &rects[i], 

 						SDL_VideoSurface, &rects[i]);

 			}

 		}

 		if ( saved_colors ) {

 			pal->colors = saved_colors;

 		}

 		/* Fall through to video surface update */

 		screen = SDL_VideoSurface;

 	}

 	if ( screen == SDL_VideoSurface ) {

 		/* Update the video surface */

 		if ( screen->offset ) {

 			for ( i=0; i<numrects; ++i ) {

 				rects[i].x += video->offset_x;

 				rects[i].y += video->offset_y;

 			}

 			video->UpdateRects(this, numrects, rects);

 			for ( i=0; i<numrects; ++i ) {

 				rects[i].x -= video->offset_x;

 				rects[i].y -= video->offset_y;

 			}

 		} else {

 			video->UpdateRects(this, numrects, rects);

 		}

 	}

 }

 /*

  * Performs hardware double buffering, if possible, or a full update if not.

  */

 int SDL_Flip(SDL_Surface *screen)

 {

 	SDL_VideoDevice *video = current_video;

 	/* Copy the shadow surface to the video surface */

 	if ( screen == SDL_ShadowSurface ) {

 		SDL_Rect rect;

 		SDL_Palette *pal = screen->format->palette;

 		SDL_Color *saved_colors = NULL;

 		if ( pal && !(SDL_VideoSurface->flags & SDL_HWPALETTE) ) {

 			/* simulated 8bpp, use correct physical palette */

 			saved_colors = pal->colors;

 			if ( video->gammacols ) {

 				/* gamma-corrected palette */

 				pal->colors = video->gammacols;

 			} else if ( video->physpal ) {

 				/* physical palette different from logical */

 				pal->colors = video->physpal->colors;

 			}

 		}

 		rect.x = 0;

 		rect.y = 0;

 		rect.w = screen->w;

 		rect.h = screen->h;

 		if ( SHOULD_DRAWCURSOR(SDL_cursorstate) ) {

 			SDL_LockCursor();

 			SDL_DrawCursor(SDL_ShadowSurface);

 			SDL_LowerBlit(SDL_ShadowSurface, &rect,

 					SDL_VideoSurface, &rect);

 			SDL_EraseCursor(SDL_ShadowSurface);

 			SDL_UnlockCursor();

 		} else {

 			SDL_LowerBlit(SDL_ShadowSurface, &rect,

 					SDL_VideoSurface, &rect);

 		}

 		if ( saved_colors ) {

 			pal->colors = saved_colors;

 		}

 		/* Fall through to video surface update */

 		screen = SDL_VideoSurface;

 	}

 	if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) {

 		SDL_VideoDevice *this  = current_video;

 		return(video->FlipHWSurface(this, SDL_VideoSurface));

 	} else {

 		SDL_UpdateRect(screen, 0, 0, 0, 0);

 	}

 	return(0);

 }

 static void SetPalette_logical(SDL_Surface *screen, SDL_Color *colors,

 			       int firstcolor, int ncolors)

 {

 	SDL_Palette *pal = screen->format->palette;

 	SDL_Palette *vidpal;

 	if ( colors != (pal->colors + firstcolor) ) {

 		memcpy(pal->colors + firstcolor, colors,

 		       ncolors * sizeof(*colors));

 	}

 	vidpal = SDL_VideoSurface->format->palette;

 	if ( (screen == SDL_ShadowSurface) && vidpal ) {

 		/*

 		 * This is a shadow surface, and the physical

 		 * framebuffer is also indexed. Propagate the

 		 * changes to its logical palette so that

 		 * updates are always identity blits

 		 */

 		memcpy(vidpal->colors + firstcolor, colors,

 		       ncolors * sizeof(*colors));

 	}

 	SDL_FormatChanged(screen);

 }

 static int SetPalette_physical(SDL_Surface *screen,

                                SDL_Color *colors, int firstcolor, int ncolors)

 {

 	SDL_VideoDevice *video = current_video;

 	int gotall = 1;

 	if ( video->physpal ) {

 		/* We need to copy the new colors, since we haven't

 		 * already done the copy in the logical set above.

 		 */

 		memcpy(video->physpal->colors + firstcolor,

 		       colors, ncolors * sizeof(*colors));

 	}

 	if ( screen == SDL_ShadowSurface ) {

 		if ( SDL_VideoSurface->flags & SDL_HWPALETTE ) {

 			/*

 			 * The real screen is also indexed - set its physical

 			 * palette. The physical palette does not include the

 			 * gamma modification, we apply it directly instead,

 			 * but this only happens if we have hardware palette.

 			 */

 			screen = SDL_VideoSurface;

 		} else {

 			/*

 			 * The video surface is not indexed - invalidate any

 			 * active shadow-to-video blit mappings.

 			 */

 			if ( screen->map->dst == SDL_VideoSurface ) {

 				SDL_InvalidateMap(screen->map);

 			}

 			if ( video->gamma ) {

 				if( ! video->gammacols ) {

 					SDL_Palette *pp = video->physpal;

 					if(!pp)

 						pp = screen->format->palette;

 					video->gammacols = malloc(pp->ncolors

 							  * sizeof(SDL_Color));

 					SDL_ApplyGamma(video->gamma,

 						       pp->colors,

 						       video->gammacols,

 						       pp->ncolors);

 				} else {

 					SDL_ApplyGamma(video->gamma, colors,

 						       video->gammacols

 						       + firstcolor,

 						       ncolors);

 				}

 			}

 			SDL_UpdateRect(screen, 0, 0, 0, 0);

 		}

 	}

 	if ( screen == SDL_VideoSurface ) {

 		SDL_Color gcolors[256];

 		if ( video->gamma ) {

 			SDL_ApplyGamma(video->gamma, colors, gcolors, ncolors);

 			colors = gcolors;

 		}

 		gotall = video->SetColors(video, firstcolor, ncolors, colors);

 		if ( ! gotall ) {

 			/* The video flags shouldn't have SDL_HWPALETTE, and

 			   the video driver is responsible for copying back the

 			   correct colors into the video surface palette.

 			*/

 			;

 		}

 		SDL_CursorPaletteChanged();

 	}

 	return gotall;

 }

 /*

  * Set the physical and/or logical colormap of a surface:

  * Only the screen has a physical colormap. It determines what is actually

  * sent to the display.

  * The logical colormap is used to map blits to/from the surface.

  * 'which' is one or both of SDL_LOGPAL, SDL_PHYSPAL

  *

  * Return nonzero if all colours were set as requested, or 0 otherwise.

  */

 int SDL_SetPalette(SDL_Surface *screen, int which,

 		   SDL_Color *colors, int firstcolor, int ncolors)

 {

 	SDL_Palette *pal;

 	int gotall;

 	int palsize;

 	if ( ! current_video ) {

 		return 0;

 	}

 	if ( screen != SDL_PublicSurface ) {

 		/* only screens have physical palettes */

 		which &= ~SDL_PHYSPAL;

 	} else if( (screen->flags & SDL_HWPALETTE) != SDL_HWPALETTE ) {

 		/* hardware palettes required for split colormaps */

 		which |= SDL_PHYSPAL | SDL_LOGPAL;

 	}

 	/* Verify the parameters */

 	pal = screen->format->palette;

 	if( !pal ) {

 		return 0;	/* not a palettized surface */

 	}

 	gotall = 1;

 	palsize = 1 << screen->format->BitsPerPixel;

 	if ( ncolors > (palsize - firstcolor) ) {

 		ncolors = (palsize - firstcolor);

 		gotall = 0;

 	}

 	if ( which & SDL_LOGPAL ) {

 		/*

 		 * Logical palette change: The actual screen isn't affected,

 		 * but the internal colormap is altered so that the

 		 * interpretation of the pixel values (for blits etc) is

 		 * changed.

 		 */

 		SetPalette_logical(screen, colors, firstcolor, ncolors);

 	}

 	if ( which & SDL_PHYSPAL ) {

 		SDL_VideoDevice *video = current_video;

 		/*

 		 * Physical palette change: This doesn't affect the

 		 * program's idea of what the screen looks like, but changes

 		 * its actual appearance.

 		 */

 		if(!video)

 			return gotall;	/* video not yet initialized */

 		if(!video->physpal && !(which & SDL_LOGPAL) ) {

 			/* Lazy physical palette allocation */

 			int size;

 			SDL_Palette *pp = malloc(sizeof(*pp));

 			if ( !pp ) {

 				return 0;

 			}

 			current_video->physpal = pp;

 			pp->ncolors = pal->ncolors;

 			size = pp->ncolors * sizeof(SDL_Color);

 			pp->colors = malloc(size);

 			if ( !pp->colors ) {

 				return 0;

 			}

 			memcpy(pp->colors, pal->colors, size);

 		}

 		if ( ! SetPalette_physical(screen,

 		                           colors, firstcolor, ncolors) ) {

 			gotall = 0;

 		}

 	}

 	return gotall;

 }

 int SDL_SetColors(SDL_Surface *screen, SDL_Color *colors, int firstcolor,

 		  int ncolors)

 {

 	return SDL_SetPalette(screen, SDL_LOGPAL | SDL_PHYSPAL,

 			      colors, firstcolor, ncolors);

 }

 /*

  * Clean up the video subsystem

  */

 void SDL_VideoQuit (void)

 {

 	SDL_Surface *ready_to_go;

 	if ( current_video ) {

 		SDL_VideoDevice *video = current_video;

 		SDL_VideoDevice *this  = current_video;

 		/* Halt event processing before doing anything else */

 		SDL_StopEventLoop();

 		/* Clean up allocated window manager items */

 		if ( SDL_PublicSurface ) {

 			SDL_PublicSurface = NULL;

 		}

 		SDL_CursorQuit();

 		/* Just in case... */

 		SDL_WM_GrabInputOff();

 		/* Clean up the system video */

 		video->VideoQuit(this);

 		/* Free any lingering surfaces */

 		ready_to_go = SDL_ShadowSurface;

 		SDL_ShadowSurface = NULL;

 		SDL_FreeSurface(ready_to_go);

 		if ( SDL_VideoSurface != NULL ) {

 			ready_to_go = SDL_VideoSurface;

 			SDL_VideoSurface = NULL;

 			SDL_FreeSurface(ready_to_go);

 		}

 		SDL_PublicSurface = NULL;

 		/* Clean up miscellaneous memory */

 		if ( video->physpal ) {

 			free(video->physpal->colors);

 			free(video->physpal);

 			video->physpal = NULL;

 		}

 		if ( video->gammacols ) {

 			free(video->gammacols);

 			video->gammacols = NULL;

 		}

 		if ( video->gamma ) {

 			free(video->gamma);

 			video->gamma = NULL;

 		}

 		if ( video->wm_title != NULL ) {

 			free(video->wm_title);

 			video->wm_title = NULL;

 		}

 		if ( video->wm_icon != NULL ) {

 			free(video->wm_icon);

 			video->wm_icon = NULL;

 		}

 		/* Finish cleaning up video subsystem */

 		video->free(this);

 		current_video = NULL;

 	}

 	return;

 }

 /* Load the GL driver library */

 int SDL_GL_LoadLibrary(const char *path)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this = current_video;

 	int retval;

 	retval = -1;

 	if ( video == NULL ) {

 		SDL_SetError("Video subsystem has not been initialized");

 	} else {

 		if ( video->GL_LoadLibrary ) {

 			retval = video->GL_LoadLibrary(this, path);

 		} else {

 			SDL_SetError("No dynamic GL support in video driver");

 		}

 	}

 	return(retval);

 }

 void *SDL_GL_GetProcAddress(const char* proc)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this = current_video;

 	void *func;

 	func = NULL;

 	if ( video->GL_GetProcAddress ) {

 		if ( video->gl_config.driver_loaded ) {

 			func = video->GL_GetProcAddress(this, proc);

 		} else {

 			SDL_SetError("No GL driver has been loaded");

 		}

 	} else {

 		SDL_SetError("No dynamic GL support in video driver");

 	}

 	return func;

 }

 /* Set the specified GL attribute for setting up a GL video mode */

 int SDL_GL_SetAttribute( SDL_GLattr attr, int value )

 {

 	int retval;

 	SDL_VideoDevice *video = current_video;

 	retval = 0;

 	switch (attr) {

 		case SDL_GL_RED_SIZE:

 			video->gl_config.red_size = value;

 			break;

 		case SDL_GL_GREEN_SIZE:

 			video->gl_config.green_size = value;

 			break;

 		case SDL_GL_BLUE_SIZE:

 			video->gl_config.blue_size = value;

 			break;

 		case SDL_GL_ALPHA_SIZE:

 			video->gl_config.alpha_size = value;

 			break;

 		case SDL_GL_DOUBLEBUFFER:

 			video->gl_config.double_buffer = value;

 			break;

 		case SDL_GL_BUFFER_SIZE:

 			video->gl_config.buffer_size = value;

 			break;

 		case SDL_GL_DEPTH_SIZE:

 			video->gl_config.depth_size = value;

 			break;

 		case SDL_GL_STENCIL_SIZE:

 			video->gl_config.stencil_size = value;

 			break;

 		case SDL_GL_ACCUM_RED_SIZE:

 			video->gl_config.accum_red_size = value;

 			break;

 		case SDL_GL_ACCUM_GREEN_SIZE:

 			video->gl_config.accum_green_size = value;

 			break;

 		case SDL_GL_ACCUM_BLUE_SIZE:

 			video->gl_config.accum_blue_size = value;

 			break;

 		case SDL_GL_ACCUM_ALPHA_SIZE:

 			video->gl_config.accum_alpha_size = value;

 			break;

 		case SDL_GL_STEREO:

 			video->gl_config.stereo = value;

 			break;

 		case SDL_GL_MULTISAMPLEBUFFERS:

 			video->gl_config.multisamplebuffers = value;

 			break;

 		case SDL_GL_MULTISAMPLESAMPLES:

 			video->gl_config.multisamplesamples = value;

 			break;

 		default:

 			SDL_SetError("Unknown OpenGL attribute");

 			retval = -1;

 			break;

 	}

 	return(retval);

 }

 /* Retrieve an attribute value from the windowing system. */

 int SDL_GL_GetAttribute(SDL_GLattr attr, int* value)

 {

 	int retval = -1;

 	SDL_VideoDevice* video = current_video;

 	SDL_VideoDevice* this = current_video;

 	if ( video->GL_GetAttribute ) {

 		retval = this->GL_GetAttribute(this, attr, value);

 	} else {

 		*value = 0;

 		SDL_SetError("GL_GetAttribute not supported");

 	}

 	return retval;

 }

 /* Perform a GL buffer swap on the current GL context */

 void SDL_GL_SwapBuffers(void)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this = current_video;

 	if ( video->screen->flags & SDL_OPENGL ) {

 		video->GL_SwapBuffers(this);

 	} else {

 		SDL_SetError("OpenGL video mode has not been set");

 	}

 }

 /* Update rects with locking */

 void SDL_GL_UpdateRectsLock(SDL_VideoDevice* this, int numrects, SDL_Rect *rects)

 {

 	SDL_GL_Lock();

  	SDL_GL_UpdateRects(numrects, rects);

 	SDL_GL_Unlock();

 }

 /* Update rects without state setting and changing (the caller is responsible for it) */

 void SDL_GL_UpdateRects(int numrects, SDL_Rect *rects)

 {

 #ifdef HAVE_OPENGL

 	SDL_VideoDevice *this = current_video;

 	SDL_Rect update, tmp;

 	int x, y, i;

 	for ( i = 0; i < numrects; i++ )

 	{

 		tmp.y = rects[i].y;

 		tmp.h = rects[i].h;

 		for ( y = 0; y <= rects[i].h / 256; y++ )

 		{

 			tmp.x = rects[i].x;

 			tmp.w = rects[i].w;

 			for ( x = 0; x <= rects[i].w / 256; x++ )

 			{

 				update.x = tmp.x;

 				update.y = tmp.y;

 				update.w = tmp.w;

 				update.h = tmp.h;

 				if ( update.w > 256 )

 					update.w = 256;

 				if ( update.h > 256 )

 					update.h = 256;

 				this->glFlush();

 				this->glTexSubImage2D( 

 					GL_TEXTURE_2D, 

 					0, 

 					0, 

 					0, 

 					update.w, 

 					update.h, 

 					this->is_32bit? GL_RGBA : GL_RGB,

 #ifdef GL_VERSION_1_2

 					this->is_32bit ? GL_UNSIGNED_BYTE : GL_UNSIGNED_SHORT_5_6_5,

 #else

 					GL_UNSIGNED_BYTE,

 #endif

 					(Uint8 *)this->screen->pixels + 

 						this->screen->format->BytesPerPixel * update.x + 

 						update.y * this->screen->pitch );

 				this->glFlush();

 				/*

 				* Note the parens around the function name:

 				* This is because some OpenGL implementations define glTexCoord etc 

 				* as macros, and we don't want them expanded here.

 				*/

 				this->glBegin(GL_TRIANGLE_STRIP);

 					(this->glTexCoord2f)( 0.0, 0.0 );	

 					(this->glVertex2i)( update.x, update.y );

 					(this->glTexCoord2f)( (float)(update.w / 256.0), 0.0 );	

 					(this->glVertex2i)( update.x + update.w, update.y );

 					(this->glTexCoord2f)( 0.0, (float)(update.h / 256.0) );

 					(this->glVertex2i)( update.x, update.y + update.h );

 					(this->glTexCoord2f)( (float)(update.w / 256.0), (float)(update.h / 256.0) );	

 					(this->glVertex2i)( update.x + update.w	, update.y + update.h );

 				this->glEnd();	

 				tmp.x += 256;

 				tmp.w -= 256;

 			}

 			tmp.y += 256;

 			tmp.h -= 256;

 		}

 	}

 #endif

 }

 /* Lock == save current state */

 void SDL_GL_Lock()

 {

 #ifdef HAVE_OPENGL

 	lock_count--;

 	if (lock_count==-1)

 	{

 		SDL_VideoDevice *this = current_video;

 		this->glPushAttrib( GL_ALL_ATTRIB_BITS );	/* TODO: narrow range of what is saved */

 #ifdef GL_CLIENT_PIXEL_STORE_BIT

 		this->glPushClientAttrib( GL_CLIENT_PIXEL_STORE_BIT );

 #endif

 		this->glEnable(GL_TEXTURE_2D);

 		this->glEnable(GL_BLEND);

 		this->glDisable(GL_FOG);

 		this->glDisable(GL_ALPHA_TEST);

 		this->glDisable(GL_DEPTH_TEST);

 		this->glDisable(GL_SCISSOR_TEST);	

 		this->glDisable(GL_STENCIL_TEST);

 		this->glDisable(GL_CULL_FACE);

 		this->glBindTexture( GL_TEXTURE_2D, this->texture );

 		this->glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );

 		this->glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );

 		this->glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );

 		this->glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );

 		this->glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );

 		this->glPixelStorei( GL_UNPACK_ROW_LENGTH, this->screen->pitch / this->screen->format->BytesPerPixel );

 		this->glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

 		(this->glColor4f)(1.0, 1.0, 1.0, 1.0);		/* Solaris workaround */

 		this->glViewport(0, 0, this->screen->w, this->screen->h);

 		this->glMatrixMode(GL_PROJECTION);

 		this->glPushMatrix();

 		this->glLoadIdentity();

 		this->glOrtho(0.0, (GLdouble) this->screen->w, (GLdouble) this->screen->h, 0.0, 0.0, 1.0);

 		this->glMatrixMode(GL_MODELVIEW);

 		this->glPushMatrix();

 		this->glLoadIdentity();

 	}

 #endif

 }

 /* Unlock == restore saved state */

 void SDL_GL_Unlock()

 {

 #ifdef HAVE_OPENGL

 	lock_count++;

 	if (lock_count==0)

 	{

 		SDL_VideoDevice *this = current_video;

 		this->glPopMatrix();

 		this->glMatrixMode(GL_PROJECTION);

 		this->glPopMatrix();

 		this->glPopClientAttrib();

 		this->glPopAttrib();

 	}

 #endif

 }

 /*

  * Sets/Gets the title and icon text of the display window, if any.

  */

 void SDL_WM_SetCaption (const char *title, const char *icon)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	if ( video ) {

 		if ( title ) {

 			if ( video->wm_title ) {

 				free(video->wm_title);

 			}

 			video->wm_title = (char *)malloc(strlen(title)+1);

 			if ( video->wm_title != NULL ) {

 				strcpy(video->wm_title, title);

 			}

 		}

 		if ( icon ) {

 			if ( video->wm_icon ) {

 				free(video->wm_icon);

 			}

 			video->wm_icon = (char *)malloc(strlen(icon)+1);

 			if ( video->wm_icon != NULL ) {

 				strcpy(video->wm_icon, icon);

 			}

 		}

 		if ( (title || icon) && (video->SetCaption != NULL) ) {

 			video->SetCaption(this, video->wm_title,video->wm_icon);

 		}

 	}

 }

 void SDL_WM_GetCaption (char **title, char **icon)

 {

 	SDL_VideoDevice *video = current_video;

 	if ( video ) {

 		if ( title ) {

 			*title = video->wm_title;

 		}

 		if ( icon ) {

 			*icon = video->wm_icon;

 		}

 	}

 }

 /* Utility function used by SDL_WM_SetIcon();

  * flags & 1 for color key, flags & 2 for alpha channel. */

 static void CreateMaskFromColorKeyOrAlpha(SDL_Surface *icon, Uint8 *mask, int flags)

 {

 	int x, y;

 	Uint32 colorkey;

 #define SET_MASKBIT(icon, x, y, mask) \

 	mask[(y*((icon->w+7)/8))+(x/8)] &= ~(0x01<<(7-(x%8)))

 	colorkey = icon->format->colorkey;

 	switch (icon->format->BytesPerPixel) {

 		case 1: { Uint8 *pixels;

 			for ( y=0; y<icon->h; ++y ) {

 				pixels = (Uint8 *)icon->pixels + y*icon->pitch;

 				for ( x=0; x<icon->w; ++x ) {

 					if ( *pixels++ == colorkey ) {

 						SET_MASKBIT(icon, x, y, mask);

 					}

 				}

 			}

 		}

 		break;

 		case 2: { Uint16 *pixels;

 			for ( y=0; y<icon->h; ++y ) {

 				pixels = (Uint16 *)icon->pixels +

 				                   y*icon->pitch/2;

 				for ( x=0; x<icon->w; ++x ) {

 					if ( (flags & 1) && *pixels == colorkey ) {

 						SET_MASKBIT(icon, x, y, mask);

 					} else if((flags & 2) && (*pixels & icon->format->Amask) == 0) {

 						SET_MASKBIT(icon, x, y, mask);

 					}

 					pixels++;

 				}

 			}

 		}

 		break;

 		case 4: { Uint32 *pixels;

 			for ( y=0; y<icon->h; ++y ) {

 				pixels = (Uint32 *)icon->pixels +

 				                   y*icon->pitch/4;

 				for ( x=0; x<icon->w; ++x ) {

 					if ( (flags & 1) && *pixels == colorkey ) {

 						SET_MASKBIT(icon, x, y, mask);

 					} else if((flags & 2) && (*pixels & icon->format->Amask) == 0) {

 						SET_MASKBIT(icon, x, y, mask);

 					}

 					pixels++;

 				}

 			}

 		}

 		break;

 	}

 }

 /*

  * Sets the window manager icon for the display window.

  */

 void SDL_WM_SetIcon (SDL_Surface *icon, Uint8 *mask)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	if ( icon && video->SetIcon ) {

 		/* Generate a mask if necessary, and create the icon! */

 		if ( mask == NULL ) {

 			int mask_len = icon->h*(icon->w+7)/8;

 			int flags = 0;

 			mask = (Uint8 *)malloc(mask_len);

 			if ( mask == NULL ) {

 				return;

 			}

 			memset(mask, ~0, mask_len);

 			if ( icon->flags & SDL_SRCCOLORKEY ) flags |= 1;

 			if ( icon->flags & SDL_SRCALPHA ) flags |= 2;

 			if( flags ) {

 				CreateMaskFromColorKeyOrAlpha(icon, mask, flags);

 			}

 			video->SetIcon(video, icon, mask);

 			free(mask);

 		} else {

 			video->SetIcon(this, icon, mask);

 		}

 	}

 }

 /*

  * Grab or ungrab the keyboard and mouse input.

  * This function returns the final grab mode after calling the

  * driver dependent function.

  */

 static SDL_GrabMode SDL_WM_GrabInputRaw(SDL_GrabMode mode)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	/* Only do something if we have support for grabs */

 	if ( video->GrabInput == NULL ) {

 		return(video->input_grab);

 	}

 	/* If the final grab mode if off, only then do we actually grab */

 #ifdef DEBUG_GRAB

   printf("SDL_WM_GrabInputRaw(%d) ... ", mode);

 #endif

 	if ( mode == SDL_GRAB_OFF ) {

 		if ( video->input_grab != SDL_GRAB_OFF ) {

 			mode = video->GrabInput(this, mode);

 		}

 	} else {

 		if ( video->input_grab == SDL_GRAB_OFF ) {

 			mode = video->GrabInput(this, mode);

 		}

 	}

 	if ( mode != video->input_grab ) {

 		video->input_grab = mode;

 		if ( video->CheckMouseMode ) {

 			video->CheckMouseMode(this);

 		}

 	}

 #ifdef DEBUG_GRAB

   printf("Final mode %d\n", video->input_grab);

 #endif

 	/* Return the final grab state */

 	if ( mode >= SDL_GRAB_FULLSCREEN ) {

 		mode -= SDL_GRAB_FULLSCREEN;

 	}

 	return(mode);

 }

 SDL_GrabMode SDL_WM_GrabInput(SDL_GrabMode mode)

 {

 	SDL_VideoDevice *video = current_video;

 	/* If the video isn't initialized yet, we can't do anything */

 	if ( ! video ) {

 		return SDL_GRAB_OFF;

 	}

 	/* Return the current mode on query */

 	if ( mode == SDL_GRAB_QUERY ) {

 		mode = video->input_grab;

 		if ( mode >= SDL_GRAB_FULLSCREEN ) {

 			mode -= SDL_GRAB_FULLSCREEN;

 		}

 		return(mode);

 	}

 #ifdef DEBUG_GRAB

   printf("SDL_WM_GrabInput(%d) ... ", mode);

 #endif

 	/* If the video surface is fullscreen, we always grab */

 	if ( mode >= SDL_GRAB_FULLSCREEN ) {

 		mode -= SDL_GRAB_FULLSCREEN;

 	}

 	if ( SDL_VideoSurface && (SDL_VideoSurface->flags & SDL_FULLSCREEN) ) {

 		mode += SDL_GRAB_FULLSCREEN;

 	}

 	return(SDL_WM_GrabInputRaw(mode));

 }

 static SDL_GrabMode SDL_WM_GrabInputOff(void)

 {

 	SDL_GrabMode mode;

 	/* First query the current grab state */

 	mode = SDL_WM_GrabInput(SDL_GRAB_QUERY);

 	/* Now explicitly turn off input grab */

 	SDL_WM_GrabInputRaw(SDL_GRAB_OFF);

 	/* Return the old state */

 	return(mode);

 }

 /*

  * Iconify the window in window managed environments.

  * A successful iconification will result in an SDL_APPACTIVE loss event.

  */

 int SDL_WM_IconifyWindow(void)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	int retval;

 	retval = 0;

 	if ( video->IconifyWindow ) {

 		retval = video->IconifyWindow(this);

 	}

 	return(retval);

 }

 /*

  * Toggle fullscreen mode

  */

 int SDL_WM_ToggleFullScreen(SDL_Surface *surface)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	int toggled;

 	toggled = 0;

 	if ( SDL_PublicSurface && (surface == SDL_PublicSurface) &&

 	     video->ToggleFullScreen ) {

 		if ( surface->flags & SDL_FULLSCREEN ) {

 			toggled = video->ToggleFullScreen(this, 0);

 			if ( toggled ) {

 				SDL_VideoSurface->flags &= ~SDL_FULLSCREEN;

 				SDL_PublicSurface->flags &= ~SDL_FULLSCREEN;

 			}

 		} else {

 			toggled = video->ToggleFullScreen(this, 1);

 			if ( toggled ) {

 				SDL_VideoSurface->flags |= SDL_FULLSCREEN;

 				SDL_PublicSurface->flags |= SDL_FULLSCREEN;

 			}

 		}

 		/* Double-check the grab state inside SDL_WM_GrabInput() */

 		if ( toggled ) {

 			SDL_WM_GrabInput(video->input_grab);

 		}

 	}

 	return(toggled);

 }

 /*

  * Get some platform dependent window manager information

  */

 int SDL_GetWMInfo (SDL_SysWMinfo *info)

 {

 	SDL_VideoDevice *video = current_video;

 	SDL_VideoDevice *this  = current_video;

 	if ( video && video->GetWMInfo ) {

 		return(video->GetWMInfo(this, info));

 	} else {

 		return(0);

 	}

 }