view src/video/xbios/SDL_xbios.c @ 4167:a6f635e5eaa6 SDL-1.2

Fixed bug #611 From Tim Angus 2008-08-12 11:18:06 I'm one of the maintainers of ioquake3.org, an updated version of the Quake 3 engine. Relatively recently, we moved ioq3 to use SDL as a replacement for 95% of the platform specific code that was there. On the whole it's doing a great job but unfortunately since the move we've been getting complaints about the quality of the mouse input on the Windows platform to the point where for many the game is unplayable. Put in other terms, the current stable SDL 1.2 is basically not fit for purpose if you need high quality mouse input as you do in a first person shooter. Over the weekend I decided to pull my finger out and actually figure out what's going on. There are basically two major problems. Firstly, when using the "windib" driver, mouse input is gathered via the WM_MOUSEMOVE message. Googling for this indicates that often this is known to result in "spurious" and/or "missing" mouse movement events; this is the primary cause of the poor mouse input. The second problem is that the "directx" driver does not work at all in combination with OpenGL meaning that you can't use DirectInput if your application also uses OpenGL. In other words you're locked into using the "windib" driver and its poor mouse input. In order to address these problems I've done the following: * Remove WM_MOUSEMOVE based motion event generation and replace with calls to GetCursorPos which seems much more reliable. In order to achieve this I've moved mouse motion out into a separate function that is called once per DIB_PumpEvents. * Remove the restriction on the "directx" driver being inoperable in combination with OpenGL. There is a bug for this issues that I've hijacked to a certain extent (http://bugzilla.libsdl.org/show_bug.cgi?id=265). I'm the first to admit I don't really understand why this restriction is there in the first place. The commit message for the bug fix that introduced this restriction (r581) isn't very elaborate and I couldn't see any other bug tracking the issue. If anyone has more information on the bug that was avoided by r581 it would be helpful as I/someone could then look into addressing the problem without disabling the "directx" driver. * I've also removed the restriction on not being allowed to use DirectInput in windowed mode. I couldn't see any reason for this, at least not from our perspective. I have my suspicions that it'll be something like matching up the cursor with the mouse coordinates... * I bumped up the DirectInput API used to version 7 in order to get access to mouse buttons 4-7. I've had to inject a little bit of the DX7 headers into SDL there as the MinGW ones aren't up to date in this respect.
author Sam Lantinga <slouken@libsdl.org>
date Thu, 02 Apr 2009 04:43:36 +0000
parents a1b03ba2fcd0
children 05c9e942cc46
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

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

/*
 * Xbios SDL video driver
 * 
 * Patrice Mandin
 */

#include <sys/stat.h>
#include <unistd.h>

/* Mint includes */
#include <mint/cookie.h>
#include <mint/osbind.h>
#include <mint/falcon.h>

#include "SDL_video.h"
#include "SDL_mouse.h"
#include "../SDL_sysvideo.h"
#include "../SDL_pixels_c.h"
#include "../../events/SDL_events_c.h"

#include "../ataricommon/SDL_ataric2p_s.h"
#include "../ataricommon/SDL_atarievents_c.h"
#include "../ataricommon/SDL_atarimxalloc_c.h"
#include "../ataricommon/SDL_atarigl_c.h"
#include "SDL_xbios.h"
#include "SDL_xbios_blowup.h"
#include "SDL_xbios_centscreen.h"
#include "SDL_xbios_sb3.h"
#include "SDL_xbios_tveille.h"

#define XBIOS_VID_DRIVER_NAME "xbios"

#ifndef C_fVDI
#define C_fVDI 0x66564449L
#endif

/* Debug print info */
#if 0
#define DEBUG_PRINT(what) \
	{ \
		printf what; \
	}
#define DEBUG_VIDEO_XBIOS 1
#else
#define DEBUG_PRINT(what)
#undef DEBUG_VIDEO_XBIOS
#endif

/* Initialization/Query functions */
static int XBIOS_VideoInit(_THIS, SDL_PixelFormat *vformat);
static SDL_Rect **XBIOS_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags);
static SDL_Surface *XBIOS_SetVideoMode(_THIS, SDL_Surface *current, int width, int height, int bpp, Uint32 flags);
static int XBIOS_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors);
static void XBIOS_VideoQuit(_THIS);

/* Hardware surface functions */
static int XBIOS_AllocHWSurface(_THIS, SDL_Surface *surface);
static int XBIOS_LockHWSurface(_THIS, SDL_Surface *surface);
static int XBIOS_FlipHWSurface(_THIS, SDL_Surface *surface);
static void XBIOS_UnlockHWSurface(_THIS, SDL_Surface *surface);
static void XBIOS_FreeHWSurface(_THIS, SDL_Surface *surface);
static void XBIOS_UpdateRects(_THIS, int numrects, SDL_Rect *rects);

#if SDL_VIDEO_OPENGL
/* OpenGL functions */
static void XBIOS_GL_SwapBuffers(_THIS);
#endif

/* To setup palette */

static unsigned short	TT_palette[256];
static unsigned long	F30_palette[256];

/* Xbios driver bootstrap functions */

static int XBIOS_Available(void)
{
	unsigned long cookie_vdo, cookie_mil, cookie_hade, cookie_scpn;
	unsigned long cookie_fvdi;
	const char *envr = SDL_getenv("SDL_VIDEODRIVER");

	/* Milan/Hades Atari clones do not have an Atari video chip */
	if ( (Getcookie(C__MIL, &cookie_mil) == C_FOUND) ||
		(Getcookie(C_hade, &cookie_hade) == C_FOUND) ) {
		return 0;
	}

	/* fVDI means graphic card, so no Xbios with it */
	if (Getcookie(C_fVDI, &cookie_fvdi) == C_FOUND) {
		if (!envr) {
			return 0;
		}
		if (SDL_strcmp(envr, XBIOS_VID_DRIVER_NAME)!=0) {
			return 0;
		}
		/* Except if we force Xbios usage, through env var */
	}

	/* Cookie _VDO present ? if not, assume ST machine */
	if (Getcookie(C__VDO, &cookie_vdo) != C_FOUND) {
		cookie_vdo = VDO_ST << 16;
	}

	/* Test if we have a monochrome monitor plugged in */
	switch( cookie_vdo >>16) {
		case VDO_ST:
		case VDO_STE:
			if ( Getrez() == (ST_HIGH>>8) )
				return 0;
			break;
		case VDO_TT:
			if ( (EgetShift() & ES_MODE) == TT_HIGH)
				return 0;
			break;
		case VDO_F30:
			if ( VgetMonitor() == MONITOR_MONO)
				return 0;
			if (Getcookie(C_SCPN, &cookie_scpn) == C_FOUND) {
				if (!SDL_XBIOS_SB3Usable((scpn_cookie_t *)cookie_scpn)) {
					return 0;
				}
			}
			break;
		default:
			return 0;
	}

	return 1;
}

static void XBIOS_DeleteDevice(SDL_VideoDevice *device)
{
	SDL_free(device->hidden);
	SDL_free(device);
}

static SDL_VideoDevice *XBIOS_CreateDevice(int devindex)
{
	SDL_VideoDevice *device;

	/* Initialize all variables that we clean on shutdown */
	device = (SDL_VideoDevice *)SDL_malloc(sizeof(SDL_VideoDevice));
	if ( device ) {
		SDL_memset(device, 0, (sizeof *device));
		device->hidden = (struct SDL_PrivateVideoData *)
				SDL_malloc((sizeof *device->hidden));
		device->gl_data = (struct SDL_PrivateGLData *)
				SDL_malloc((sizeof *device->gl_data));
	}
	if ( (device == NULL) || (device->hidden == NULL) ) {
		SDL_OutOfMemory();
		if ( device ) {
			SDL_free(device);
		}
		return(0);
	}
	SDL_memset(device->hidden, 0, (sizeof *device->hidden));
	SDL_memset(device->gl_data, 0, sizeof(*device->gl_data));

	/* Video functions */
	device->VideoInit = XBIOS_VideoInit;
	device->ListModes = XBIOS_ListModes;
	device->SetVideoMode = XBIOS_SetVideoMode;
	device->SetColors = XBIOS_SetColors;
	device->UpdateRects = NULL;
	device->VideoQuit = XBIOS_VideoQuit;
	device->AllocHWSurface = XBIOS_AllocHWSurface;
	device->LockHWSurface = XBIOS_LockHWSurface;
	device->UnlockHWSurface = XBIOS_UnlockHWSurface;
	device->FlipHWSurface = XBIOS_FlipHWSurface;
	device->FreeHWSurface = XBIOS_FreeHWSurface;

#if SDL_VIDEO_OPENGL
	/* OpenGL functions */
	device->GL_LoadLibrary = SDL_AtariGL_LoadLibrary;
	device->GL_GetProcAddress = SDL_AtariGL_GetProcAddress;
	device->GL_GetAttribute = SDL_AtariGL_GetAttribute;
	device->GL_MakeCurrent = SDL_AtariGL_MakeCurrent;
	device->GL_SwapBuffers = XBIOS_GL_SwapBuffers;
#endif

	/* Events */
	device->InitOSKeymap = Atari_InitOSKeymap;
	device->PumpEvents = Atari_PumpEvents;

	device->free = XBIOS_DeleteDevice;

	return device;
}

VideoBootStrap XBIOS_bootstrap = {
	XBIOS_VID_DRIVER_NAME, "Atari Xbios driver",
	XBIOS_Available, XBIOS_CreateDevice
};

void SDL_XBIOS_AddMode(_THIS, Uint16 modecode, Uint16 width, Uint16 height,
	Uint16 depth, SDL_bool flags)
{
	int i, curpos;
	xbiosmode_t *current_mode;

	/* Check if mode already exists */
	if (XBIOS_modelist) {
		current_mode = XBIOS_modelist;
		for (i=0;i<XBIOS_nummodes; i++, current_mode++) {
			if (current_mode->width != width)
				continue;
			if (current_mode->height != height)
				continue;
			if (current_mode->depth != depth)
				continue;
			return;
		}
	}

	++XBIOS_nummodes;
	XBIOS_modelist = (xbiosmode_t *) SDL_realloc(XBIOS_modelist, XBIOS_nummodes * sizeof(xbiosmode_t));

	/* Keep the list sorted: bpp, width, height */
	curpos=0;

	for(i=0; i<XBIOS_nummodes-1; i++) {
		if (XBIOS_modelist[i].depth <= depth) {
			if (XBIOS_modelist[i].width < width) {
				break;
			} else if (XBIOS_modelist[i].width == width) {
				if (XBIOS_modelist[i].height <= height) {
					break;
				}
			}
		}
		curpos++;
	}

	/* Push remaining modes further */
	for(i=XBIOS_nummodes-1; i>curpos; i--) {
		SDL_memcpy(&XBIOS_modelist[i], &XBIOS_modelist[i-1], sizeof(xbiosmode_t));
	}

	XBIOS_modelist[curpos].number = modecode;
	XBIOS_modelist[curpos].width = width;
	XBIOS_modelist[curpos].height = height;
	XBIOS_modelist[curpos].depth = depth;
	XBIOS_modelist[curpos].doubleline = flags;
}

static int XBIOS_VideoInit(_THIS, SDL_PixelFormat *vformat)
{
	int i,j8,j16;
	xbiosmode_t *current_mode;
	unsigned long cookie_blow, cookie_scpn, cookie_cnts;

	/* Initialize all variables that we clean on shutdown */
	memset (SDL_modelist, 0, sizeof(SDL_modelist));

	/* Cookie _VDO present ? if not, assume ST machine */
	if (Getcookie(C__VDO, &XBIOS_cvdo) != C_FOUND) {
		XBIOS_cvdo = VDO_ST << 16;
	}

	/* Allocate memory for old palette */
	XBIOS_oldpalette = (void *)SDL_malloc(256*sizeof(long));
	if ( !XBIOS_oldpalette ) {
		SDL_SetError("Unable to allocate memory for old palette\n");
		return(-1);
	}

	/* Initialize video mode list */
	/* and save current screen status (palette, screen address, video mode) */
	XBIOS_nummodes = 0;
	XBIOS_modelist = NULL;
	XBIOS_centscreen = SDL_FALSE;

	switch (XBIOS_cvdo >>16) {
		case VDO_ST:
		case VDO_STE:
			{
				short *oldpalette;

				SDL_XBIOS_AddMode(this, ST_LOW>>8,320,200,4,SDL_FALSE);
			
				XBIOS_oldvbase=Physbase();
				XBIOS_oldvmode=Getrez();
				switch(XBIOS_oldvmode << 8) {
					case ST_LOW:
						XBIOS_oldnumcol=16;
						break;
					case ST_MED:
						XBIOS_oldnumcol=4;
						break;
					case ST_HIGH:
						XBIOS_oldnumcol=2;
						break;
					default:
						XBIOS_oldnumcol=0;
						break;
				}

				oldpalette= (short *) XBIOS_oldpalette;
				for (i=0;i<XBIOS_oldnumcol;i++) {
					*oldpalette++=Setcolor(i,-1);
				}

				vformat->BitsPerPixel = 8;
			}
			break;
		case VDO_TT:

			SDL_XBIOS_AddMode(this, TT_LOW,320,480,8,SDL_FALSE);
			/* Software double-lined mode */
			SDL_XBIOS_AddMode(this, TT_LOW,320,240,8,SDL_TRUE);

			XBIOS_oldvbase=Logbase();
			XBIOS_oldvmode=EgetShift();

			switch(XBIOS_oldvmode & ES_MODE) {
				case TT_LOW:
					XBIOS_oldnumcol=256;
					break;
				case ST_LOW:
				case TT_MED:
					XBIOS_oldnumcol=16;
					break;
				case ST_MED:
					XBIOS_oldnumcol=4;
					break;
				case ST_HIGH:
				case TT_HIGH:
					XBIOS_oldnumcol=2;
					break;
				default:
					XBIOS_oldnumcol=0;
					break;
			}
			if (XBIOS_oldnumcol) {
				EgetPalette(0, XBIOS_oldnumcol, XBIOS_oldpalette);
			}

			vformat->BitsPerPixel = 8;
			break;
		case VDO_F30:
			switch (VgetMonitor())
			{
				case MONITOR_MONO:
					/* Not usable */
					break;
				case MONITOR_RGB:
				case MONITOR_TV:
					SDL_XBIOS_AddMode(this, BPS16|COL80|OVERSCAN|VERTFLAG,768,480,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|COL80|OVERSCAN,768,240,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|COL80|VERTFLAG,640,400,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|COL80,640,200,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|OVERSCAN|VERTFLAG,384,480,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|OVERSCAN,384,240,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|VERTFLAG,320,400,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16,320,200,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80|OVERSCAN|VERTFLAG,768,480,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80|OVERSCAN,768,240,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80|VERTFLAG,640,400,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80,640,200,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|OVERSCAN|VERTFLAG,384,480,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|OVERSCAN,384,240,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|VERTFLAG,320,400,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8,320,200,8,SDL_FALSE);
					break;
				case MONITOR_VGA:
					SDL_XBIOS_AddMode(this, BPS16,320,480,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS16|VERTFLAG,320,240,16,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80,640,480,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|COL80|VERTFLAG,640,240,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8,320,480,8,SDL_FALSE);
					SDL_XBIOS_AddMode(this, BPS8|VERTFLAG,320,240,8,SDL_FALSE);
					break;
			}
			XBIOS_oldvbase=Logbase();
			XBIOS_oldvmode=VsetMode(-1);

			XBIOS_oldnumcol= 1<< (1 << (XBIOS_oldvmode & NUMCOLS));
			if (XBIOS_oldnumcol > 256) {
				XBIOS_oldnumcol = 0;
			}
			if (XBIOS_oldnumcol) {
				VgetRGB(0, XBIOS_oldnumcol, XBIOS_oldpalette);
			}

			vformat->BitsPerPixel = 16;

			/* Keep vga/rvb, and pal/ntsc bits */
			current_mode = XBIOS_modelist;
			for (i=0;i<XBIOS_nummodes;i++) {
				Uint16 newvmode;			

				newvmode = current_mode->number;
				newvmode &= ~(VGA|PAL);
				newvmode |= XBIOS_oldvmode & (VGA|PAL);
				current_mode->number = newvmode;
				
				current_mode++;
			}

			/* Initialize BlowUp/SB3/Centscreen stuff if present */
			if (Getcookie(C_BLOW, &cookie_blow) == C_FOUND) {
				SDL_XBIOS_BlowupInit(this, (blow_cookie_t *)cookie_blow);
			} else if (Getcookie(C_SCPN, &cookie_scpn) == C_FOUND) {
				SDL_XBIOS_SB3Init(this, (scpn_cookie_t *)cookie_scpn);
			} else if (Getcookie(C_CNTS, &cookie_cnts) == C_FOUND) {
				XBIOS_oldvmode = SDL_XBIOS_CentscreenInit(this);
				XBIOS_centscreen = SDL_TRUE;
			}

			break;
	}

	/* Determine the current screen size */
	if ( XBIOS_nummodes > 0 ) {
		/* FIXME: parse video mode list to search for current mode */
		this->info.current_w = XBIOS_modelist[0].width;
		this->info.current_h = XBIOS_modelist[0].height;
	}

	current_mode = XBIOS_modelist;
	j8 = j16 = 0;
	for (i=0; i<XBIOS_nummodes; i++, current_mode++) {
		switch (current_mode->depth) {
			case 4:
			case 8:
				SDL_modelist[0][j8] = SDL_malloc(sizeof(SDL_Rect));
				SDL_modelist[0][j8]->x = SDL_modelist[0][j8]->y = 0;
				SDL_modelist[0][j8]->w = current_mode->width;
				SDL_modelist[0][j8]->h = current_mode->height;
				XBIOS_videomodes[0][j8]=current_mode;
				j8++;
				break;
			case 16:
				SDL_modelist[1][j16] = SDL_malloc(sizeof(SDL_Rect));
				SDL_modelist[1][j16]->x = SDL_modelist[1][j16]->y = 0;
				SDL_modelist[1][j16]->w = current_mode->width;
				SDL_modelist[1][j16]->h = current_mode->height;
				XBIOS_videomodes[1][j16]=current_mode;
				j16++;
				break;
		}		
	}
	SDL_modelist[0][j8] = NULL;
	SDL_modelist[1][j16] = NULL;

	XBIOS_screens[0]=NULL;
	XBIOS_screens[1]=NULL;
	XBIOS_shadowscreen=NULL;

	/* Update hardware info */
	this->info.hw_available = 1;
	this->info.video_mem = (Uint32) Atari_SysMalloc(-1L, MX_STRAM);

	/* Init chunky to planar routine */
	SDL_Atari_C2pConvert = SDL_Atari_C2pConvert8;

#if SDL_VIDEO_OPENGL
	SDL_AtariGL_InitPointers(this);
#endif

	/* Disable screensavers */
	if (SDL_XBIOS_TveillePresent(this)) {
		SDL_XBIOS_TveilleDisable(this);
	}

	/* We're done! */
	return(0);
}

static SDL_Rect **XBIOS_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags)
{
	/* 8 bits -> list 0 */
	/* 16 bits -> list 1 */
	if ((format->BitsPerPixel != 8) && (format->BitsPerPixel !=16)) {
		return NULL;
	}

	return(SDL_modelist[(format->BitsPerPixel)>>4]);
}

static void XBIOS_FreeBuffers(_THIS)
{
	int i;

	for (i=0;i<2;i++) {
		if (XBIOS_screensmem[i]!=NULL) {
			Mfree(XBIOS_screensmem[i]);
			XBIOS_screensmem[i]=NULL;
		}
	}

	if (XBIOS_shadowscreen!=NULL) {
		Mfree(XBIOS_shadowscreen);
		XBIOS_shadowscreen=NULL;
	}
}

static SDL_Surface *XBIOS_SetVideoMode(_THIS, SDL_Surface *current,
				int width, int height, int bpp, Uint32 flags)
{
	int mode, new_depth;
	int i;
	xbiosmode_t *new_video_mode;
	Uint32 new_screen_size;
	Uint32 modeflags;

	/* Free current buffers */
	XBIOS_FreeBuffers(this);

	/* Limit bpp */
	if (bpp>16) {
		bpp = 16;
	}
	bpp >>= 4;

	/* Search if the mode exists (width, height, bpp) */
	for ( mode=0; SDL_modelist[bpp][mode]; ++mode ) {
		if ( (SDL_modelist[bpp][mode]->w == width) &&
		     (SDL_modelist[bpp][mode]->h == height) ) {

			break;
		}
	}
	if ( SDL_modelist[bpp][mode] == NULL ) {
		SDL_SetError("Couldn't find requested mode in list");
		return(NULL);
	}

	modeflags = SDL_FULLSCREEN | SDL_PREALLOC;

	/* Allocate needed buffers: simple/double buffer and shadow surface */
	new_video_mode = XBIOS_videomodes[bpp][mode];
	new_depth = new_video_mode->depth;
	if (new_depth == 4) {
		SDL_Atari_C2pConvert = SDL_Atari_C2pConvert4;
		new_depth=8;
		modeflags |= SDL_SWSURFACE|SDL_HWPALETTE;
	} else if (new_depth == 8) {
		SDL_Atari_C2pConvert = SDL_Atari_C2pConvert8;
		modeflags |= SDL_SWSURFACE|SDL_HWPALETTE;
	} else {
		modeflags |= SDL_HWSURFACE;
	}

	new_screen_size = width * height * ((new_depth)>>3);
	new_screen_size += 256; /* To align on a 256 byte adress */	

	if (new_depth == 8) {
		XBIOS_shadowscreen = Atari_SysMalloc(new_screen_size, MX_PREFTTRAM);

		if (XBIOS_shadowscreen == NULL) {
			SDL_SetError("Can not allocate %d KB for shadow buffer", new_screen_size>>10);
			return (NULL);
		}
		SDL_memset(XBIOS_shadowscreen, 0, new_screen_size);
	}

	/* Output buffer needs to be twice in size for the software double-line mode */
	XBIOS_doubleline = SDL_FALSE;
	if (new_video_mode->doubleline) {
		new_screen_size <<= 1;
		XBIOS_doubleline = SDL_TRUE;
	}

	XBIOS_screensmem[0] = Atari_SysMalloc(new_screen_size, MX_STRAM);

	if (XBIOS_screensmem[0]==NULL) {
		XBIOS_FreeBuffers(this);
		SDL_SetError("Can not allocate %d KB for frame buffer", new_screen_size>>10);
		return (NULL);
	}
	SDL_memset(XBIOS_screensmem[0], 0, new_screen_size);

	XBIOS_screens[0]=(void *) (( (long) XBIOS_screensmem[0]+256) & 0xFFFFFF00UL);

#if SDL_VIDEO_OPENGL
	if (flags & SDL_OPENGL) {
		if (this->gl_config.double_buffer) {
			flags |= SDL_DOUBLEBUF;
		}
	}
#endif

	/* Double buffer ? */
	if (flags & SDL_DOUBLEBUF) {
		XBIOS_screensmem[1] = Atari_SysMalloc(new_screen_size, MX_STRAM);

		if (XBIOS_screensmem[1]==NULL) {
			XBIOS_FreeBuffers(this);
			SDL_SetError("Can not allocate %d KB for double buffer", new_screen_size>>10);
			return (NULL);
		}
		SDL_memset(XBIOS_screensmem[1], 0, new_screen_size);

		XBIOS_screens[1]=(void *) (( (long) XBIOS_screensmem[1]+256) & 0xFFFFFF00UL);
		modeflags |= SDL_DOUBLEBUF;
	}
	
	/* Allocate the new pixel format for the screen */
	if ( ! SDL_ReallocFormat(current, new_depth, 0, 0, 0, 0) ) {
		XBIOS_FreeBuffers(this);
		SDL_SetError("Couldn't allocate new pixel format for requested mode");
		return(NULL);
	}

	current->w = XBIOS_width = width;
	current->h = XBIOS_height = height;
	current->pitch = (width * new_depth)>>3;

	/* this is for C2P conversion */
	XBIOS_pitch = (new_video_mode->width * new_video_mode->depth)>>3;

	if (new_depth == 8)
		current->pixels = XBIOS_shadowscreen;
	else
		current->pixels = XBIOS_screens[0];

	XBIOS_fbnum = 0;

#if SDL_VIDEO_OPENGL
	if (flags & SDL_OPENGL) {
		if (!SDL_AtariGL_Init(this, current)) {
			XBIOS_FreeBuffers(this);
			SDL_SetError("Can not create OpenGL context");
			return NULL;
		}

		modeflags |= SDL_OPENGL;
	}
#endif

	current->flags = modeflags;

	/* Now set the video mode */
#ifndef DEBUG_VIDEO_XBIOS
	Setscreen(-1,XBIOS_screens[0],-1);
#endif

	switch(XBIOS_cvdo >> 16) {
		case VDO_ST:
#ifndef DEBUG_VIDEO_XBIOS
			Setscreen(-1,-1,new_video_mode->number);
#endif
			/* Reset palette */
			for (i=0;i<16;i++) {
				TT_palette[i]= ((i>>1)<<8) | (((i*8)/17)<<4) | (i>>1);
			}
#ifndef DEBUG_VIDEO_XBIOS
			Setpalette(TT_palette);
#endif
			break;
		case VDO_STE:
#ifndef DEBUG_VIDEO_XBIOS
			Setscreen(-1,-1,new_video_mode->number);
#endif
			/* Reset palette */
			for (i=0;i<16;i++)
			{
				int c;

				c=((i&1)<<3)|((i>>1)&7);
				TT_palette[i]=(c<<8)|(c<<4)|c;
			}
#ifndef DEBUG_VIDEO_XBIOS
			Setpalette(TT_palette);
#endif
			break;
		case VDO_TT:
#ifndef DEBUG_VIDEO_XBIOS
			EsetShift(new_video_mode->number);
#endif
			break;
		case VDO_F30:
#ifndef DEBUG_VIDEO_XBIOS
			if (XBIOS_centscreen) {
				SDL_XBIOS_CentscreenSetmode(this, width, height, new_depth);
			} else {
				VsetMode(new_video_mode->number);
			}
#endif
			/* Set hardware palette to black in True Colour */
			if (new_depth == 16) {
				SDL_memset(F30_palette, 0, sizeof(F30_palette));
				VsetRGB(0,256,F30_palette);
			}
			break;
	}

	Vsync();

	this->UpdateRects = XBIOS_UpdateRects;

	return (current);
}

/* We don't actually allow hardware surfaces other than the main one */
static int XBIOS_AllocHWSurface(_THIS, SDL_Surface *surface)
{
	return(-1);
}

static void XBIOS_FreeHWSurface(_THIS, SDL_Surface *surface)
{
	return;
}

static int XBIOS_LockHWSurface(_THIS, SDL_Surface *surface)
{
	return(0);
}

static void XBIOS_UnlockHWSurface(_THIS, SDL_Surface *surface)
{
	return;
}

static void XBIOS_UpdateRects(_THIS, int numrects, SDL_Rect *rects)
{
	SDL_Surface *surface;

	surface = this->screen;

	if ((surface->format->BitsPerPixel) == 8) {
		int i;

		for (i=0;i<numrects;i++) {
			void *source,*destination;
			int x1,x2;

			x1 = rects[i].x & ~15;
			x2 = rects[i].x+rects[i].w;
			if (x2 & 15) {
				x2 = (x2 | 15) +1;
			}

			source = surface->pixels;
			source += surface->pitch * rects[i].y;
			source += x1;

			destination = XBIOS_screens[XBIOS_fbnum];
			destination += XBIOS_pitch * rects[i].y;
			destination += x1;

			/* Convert chunky to planar screen */
			SDL_Atari_C2pConvert(
				source,
				destination,
				x2-x1,
				rects[i].h,
				XBIOS_doubleline,
				surface->pitch,
				XBIOS_pitch
			);
		}
	}

#ifndef DEBUG_VIDEO_XBIOS
	Setscreen(-1,XBIOS_screens[XBIOS_fbnum],-1);
#endif
	Vsync();

	if ((surface->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF) {
		XBIOS_fbnum ^= 1;
		if ((surface->format->BitsPerPixel) > 8) {
			surface->pixels=XBIOS_screens[XBIOS_fbnum];
		}
	}
}

static int XBIOS_FlipHWSurface(_THIS, SDL_Surface *surface)
{
	if ((surface->format->BitsPerPixel) == 8) {
		void *destscr;
		int destx;
			
		/* Center on destination screen */
		destscr = XBIOS_screens[XBIOS_fbnum];
		destscr += XBIOS_pitch * ((XBIOS_height - surface->h) >> 1);
		destx = (XBIOS_width - surface->w) >> 1;
		destx &= ~15;
		destscr += destx;

		/* Convert chunky to planar screen */
		SDL_Atari_C2pConvert(
			surface->pixels,
			destscr,
			surface->w,
			surface->h,
			XBIOS_doubleline,
			surface->pitch,
			XBIOS_pitch
		);
	}

#ifndef DEBUG_VIDEO_XBIOS
	Setscreen(-1,XBIOS_screens[XBIOS_fbnum],-1);
#endif
	Vsync();

	if ((surface->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF) {
		XBIOS_fbnum ^= 1;
		if ((surface->format->BitsPerPixel) > 8) {
			surface->pixels=XBIOS_screens[XBIOS_fbnum];
		}
	}

	return(0);
}

static int XBIOS_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors)
{
	int		i;
	int		r,v,b;

	switch( XBIOS_cvdo >> 16) {
		case VDO_ST:
		case VDO_STE:
		 	for (i=0;i<ncolors;i++)
			{
				r = colors[i].r;	
				v = colors[i].g;
				b = colors[i].b;

				TT_palette[firstcolor+i]=((r*30)+(v*59)+(b*11))/100;
			}
			SDL_Atari_C2pConvert4_pal(TT_palette); /* convert the lighting */
			break;
		case VDO_TT:
			for(i = 0; i < ncolors; i++)
			{
				r = colors[i].r;	
				v = colors[i].g;
				b = colors[i].b;
					
				TT_palette[i]=((r>>4)<<8)|((v>>4)<<4)|(b>>4);
			}
#ifndef DEBUG_VIDEO_XBIOS
			EsetPalette(firstcolor,ncolors,TT_palette);
#endif
			break;
		case VDO_F30:
			for(i = 0; i < ncolors; i++)
			{
				r = colors[i].r;	
				v = colors[i].g;
				b = colors[i].b;

				F30_palette[i]=(r<<16)|(v<<8)|b;
			}
#ifndef DEBUG_VIDEO_XBIOS
			VsetRGB(firstcolor,ncolors,F30_palette);
#endif
			break;
	}

	return(1);
}

/* Note:  If we are terminated, this could be called in the middle of
   another SDL video routine -- notably UpdateRects.
*/
static void XBIOS_VideoQuit(_THIS)
{
	int i,j;

	Atari_ShutdownEvents();

	/* Restore video mode and palette */
#ifndef DEBUG_VIDEO_XBIOS
	switch(XBIOS_cvdo >> 16) {
		case VDO_ST:
		case VDO_STE:
			Setscreen(-1,XBIOS_oldvbase,XBIOS_oldvmode);
			if (XBIOS_oldnumcol) {
				Setpalette(XBIOS_oldpalette);
			}
			break;
		case VDO_TT:
			Setscreen(-1,XBIOS_oldvbase,-1);
			EsetShift(XBIOS_oldvmode);
			if (XBIOS_oldnumcol) {
				EsetPalette(0, XBIOS_oldnumcol, XBIOS_oldpalette);
			}
			break;
		case VDO_F30:
			Setscreen(-1, XBIOS_oldvbase, -1);
			if (XBIOS_centscreen) {
				SDL_XBIOS_CentscreenRestore(this, XBIOS_oldvmode);
			} else {
				VsetMode(XBIOS_oldvmode);
			}
			if (XBIOS_oldnumcol) {
				VsetRGB(0, XBIOS_oldnumcol, XBIOS_oldpalette);
			}
			break;
	}
	Vsync();
#endif


#if SDL_VIDEO_OPENGL
	if (gl_active) {
		SDL_AtariGL_Quit(this, SDL_TRUE);
	}
#endif

	if (XBIOS_oldpalette) {
		SDL_free(XBIOS_oldpalette);
		XBIOS_oldpalette=NULL;
	}
	XBIOS_FreeBuffers(this);

	/* Free mode list */
	for (j=0;j<NUM_MODELISTS;j++) {
		for (i=0;i<SDL_NUMMODES;i++) {
			if (SDL_modelist[j][i]!=NULL) {
				SDL_free(SDL_modelist[j][i]);
				SDL_modelist[j][i]=NULL;
			}
		}
	}

	if (XBIOS_modelist) {
		SDL_free(XBIOS_modelist);
		XBIOS_nummodes=0;
		XBIOS_modelist=NULL;
	}

	this->screen->pixels = NULL;	

	/* Restore screensavers */
	if (SDL_XBIOS_TveillePresent(this)) {
		SDL_XBIOS_TveilleRestore(this);
	}
}

#if SDL_VIDEO_OPENGL

static void XBIOS_GL_SwapBuffers(_THIS)
{
	SDL_AtariGL_SwapBuffers(this);
	XBIOS_FlipHWSurface(this, this->screen);
	SDL_AtariGL_MakeCurrent(this);
}

#endif