view src/video/aalib/SDL_aavideo.c @ 1554:0ca607a5d173

Fixed bug #84 Date: Sun, 23 Oct 2005 16:39:03 +0200 From: "A. Schmid" <sahib@phreaker.net> Subject: [SDL] no software surfaces with svgalib driver? Hi, I noticed that the SDL (1.2.9) svgalib driver only makes use of linear addressable (framebuffer) video modes. On older systems (like one of mine), linear addressable modes are often not available. Especially for cards with VESA VBE < 2.0 the svgalib vesa driver is unusable, since VESA only supports framebuffering for VBE 2.0 and later. The changes necessary to add support for software surfaces seem to be relatively small. I only had to hack src/video/svga/SDL_svgavideo.c (see attached patch). The code worked fine for me, but it is no more than a proof of concept and should be reviewed (probably has a memory leak when switching modes). It also uses the vgagl library (included in the svgalib package) and needs to be linked against it. -Alex
author Sam Lantinga <slouken@libsdl.org>
date Sun, 19 Mar 2006 12:04:40 +0000
parents d910939febfa
children 782fd950bd46 c121d94672cb a1b03ba2fcd0
line wrap: on
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/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 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"

/* AAlib based SDL video driver implementation.
*/

#include <unistd.h>
#include <sys/stat.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 "SDL_aavideo.h"
#include "SDL_aaevents_c.h"
#include "SDL_aamouse_c.h"

#include <aalib.h>

/* Initialization/Query functions */
static int AA_VideoInit(_THIS, SDL_PixelFormat *vformat);
static SDL_Rect **AA_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags);
static SDL_Surface *AA_SetVideoMode(_THIS, SDL_Surface *current, int width, int height, int bpp, Uint32 flags);
static int AA_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors);
static void AA_VideoQuit(_THIS);

/* Hardware surface functions */
static int AA_AllocHWSurface(_THIS, SDL_Surface *surface);
static int AA_LockHWSurface(_THIS, SDL_Surface *surface);
static int AA_FlipHWSurface(_THIS, SDL_Surface *surface);
static void AA_UnlockHWSurface(_THIS, SDL_Surface *surface);
static void AA_FreeHWSurface(_THIS, SDL_Surface *surface);

/* Cache the VideoDevice struct */
static struct SDL_VideoDevice *local_this;

/* AAlib driver bootstrap functions */

static int AA_Available(void)
{
	return 1; /* Always available ! */
}

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

static SDL_VideoDevice *AA_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));
	}
	if ( (device == NULL) || (device->hidden == NULL) ) {
		SDL_OutOfMemory();
		if ( device ) {
			SDL_free(device);
		}
		return(0);
	}
	SDL_memset(device->hidden, 0, (sizeof *device->hidden));

	/* Set the function pointers */
	device->VideoInit = AA_VideoInit;
	device->ListModes = AA_ListModes;
	device->SetVideoMode = AA_SetVideoMode;
	device->CreateYUVOverlay = NULL;
	device->SetColors = AA_SetColors;
	device->UpdateRects = NULL;
	device->VideoQuit = AA_VideoQuit;
	device->AllocHWSurface = AA_AllocHWSurface;
	device->CheckHWBlit = NULL;
	device->FillHWRect = NULL;
	device->SetHWColorKey = NULL;
	device->SetHWAlpha = NULL;
	device->LockHWSurface = AA_LockHWSurface;
	device->UnlockHWSurface = AA_UnlockHWSurface;
	device->FlipHWSurface = NULL;
	device->FreeHWSurface = AA_FreeHWSurface;
	device->SetCaption = NULL;
	device->SetIcon = NULL;
	device->IconifyWindow = NULL;
	device->GrabInput = NULL;
	device->GetWMInfo = NULL;
	device->InitOSKeymap = AA_InitOSKeymap;
	device->PumpEvents = AA_PumpEvents;

	device->free = AA_DeleteDevice;

	return device;
}

VideoBootStrap AALIB_bootstrap = {
	"aalib", "ASCII Art Library",
	AA_Available, AA_CreateDevice
};

static void AA_ResizeHandler(aa_context *);

int AA_VideoInit(_THIS, SDL_PixelFormat *vformat)
{
	int keyboard;
	int i;

	/* Initialize all variables that we clean on shutdown */
	for ( i=0; i<SDL_NUMMODES; ++i ) {
		SDL_modelist[i] = SDL_malloc(sizeof(SDL_Rect));
		SDL_modelist[i]->x = SDL_modelist[i]->y = 0;
	}
	/* Modes sorted largest to smallest */
	SDL_modelist[0]->w = 1024; SDL_modelist[0]->h = 768;
	SDL_modelist[1]->w = 800; SDL_modelist[1]->h = 600;
	SDL_modelist[2]->w = 640; SDL_modelist[2]->h = 480;
	SDL_modelist[3]->w = 320; SDL_modelist[3]->h = 400;
	SDL_modelist[4]->w = 320; SDL_modelist[4]->h = 240;
	SDL_modelist[5]->w = 320; SDL_modelist[5]->h = 200;
	SDL_modelist[6] = NULL;

	/* Initialize the library */

	AA_mutex = SDL_CreateMutex();

	aa_parseoptions (NULL, NULL, NULL, NULL);

	AA_context = aa_autoinit(&aa_defparams);
	if ( ! AA_context ) {
		SDL_SetError("Unable to initialize AAlib");
		return(-1);
	}

	/* Enable mouse and keyboard support */

	if ( ! aa_autoinitkbd (AA_context, AA_SENDRELEASE) ) {
		SDL_SetError("Unable to initialize AAlib keyboard");
		return(-1);
	}
	if ( ! aa_autoinitmouse (AA_context, AA_SENDRELEASE) ) {
		fprintf(stderr,"Warning: Unable to initialize AAlib mouse");
	}
	AA_rparams = aa_getrenderparams();

	local_this = this;

	aa_resizehandler(AA_context, AA_ResizeHandler);

	fprintf(stderr,"Using AAlib driver: %s (%s)\n", AA_context->driver->name, AA_context->driver->shortname);

	AA_in_x11 = (SDL_strcmp(AA_context->driver->shortname,"X11") == 0);
	/* Determine the screen depth (use default 8-bit depth) */
	vformat->BitsPerPixel = 8;
	vformat->BytesPerPixel = 1;

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

SDL_Rect **AA_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags)
{
     if(format->BitsPerPixel != 8)
 		return NULL;

	 if ( flags & SDL_FULLSCREEN ) {
		 return SDL_modelist;
	 } else {
		 return (SDL_Rect **) -1;
	 }
}

/* From aavga.c
   AAlib does not give us the choice of the actual resolution, thus we have to simulate additional
   resolution by scaling down manually each frame
*/
static void fastscale (register char *b1, register char *b2, int x1, int x2, int y1, int y2)
{
	register int ex, spx = 0, ddx, ddx1;
	int ddy1, ddy, spy = 0, ey;
	int x;
	char *bb1 = b1;
	if (!x1 || !x2 || !y1 || !y2)
		return;
	ddx = x1 + x1;
	ddx1 = x2 + x2;
	if (ddx1 < ddx)
		spx = ddx / ddx1, ddx %= ddx1;
	ddy = y1 + y1;
	ddy1 = y2 + y2;
	if (ddy1 < ddy)
		spy = (ddy / ddy1) * x1, ddy %= ddy1;
	ey = -ddy1;
	for (; y2; y2--) {
		ex = -ddx1;
		for (x = x2; x; x--) {
			*b2 = *b1;
			b2++;
			b1 += spx;
			ex += ddx;
			if (ex > 0) {
				b1++;
				ex -= ddx1;
			}
		}
		bb1 += spy;
		ey += ddy;
		if (ey > 0) {
			bb1 += x1;
			ey -= ddy1;
		}
		b1 = bb1;
	}
}

/* Various screen update functions available */
static void AA_DirectUpdate(_THIS, int numrects, SDL_Rect *rects);

SDL_Surface *AA_SetVideoMode(_THIS, SDL_Surface *current,
				int width, int height, int bpp, Uint32 flags)
{
	int mode;

	if ( AA_buffer ) {
		SDL_free( AA_buffer );
	}

	AA_buffer = SDL_malloc(width * height);
	if ( ! AA_buffer ) {
		SDL_SetError("Couldn't allocate buffer for requested mode");
		return(NULL);
	}

/* 	printf("Setting mode %dx%d\n", width, height); */

	SDL_memset(aa_image(AA_context), 0, aa_imgwidth(AA_context) * aa_imgheight(AA_context));
	SDL_memset(AA_buffer, 0, width * height);

	/* Allocate the new pixel format for the screen */
	if ( ! SDL_ReallocFormat(current, 8, 0, 0, 0, 0) ) {
		return(NULL);
	}

	/* Set up the new mode framebuffer */
	current->flags = SDL_FULLSCREEN;
	AA_w = current->w = width;
	AA_h = current->h = height;
	current->pitch = current->w;
	current->pixels = AA_buffer;

	AA_x_ratio = ((double)aa_imgwidth(AA_context)) / ((double)width);
	AA_y_ratio = ((double)aa_imgheight(AA_context)) / ((double)height);

	/* Set the blit function */
	this->UpdateRects = AA_DirectUpdate;

	/* We're done */
	return(current);
}

static void AA_ResizeHandler(aa_context *context)
{
	aa_resize(context);
	local_this->hidden->x_ratio = ((double)aa_imgwidth(context)) / ((double)local_this->screen->w);
	local_this->hidden->y_ratio = ((double)aa_imgheight(context)) / ((double)local_this->screen->h);

	fastscale (local_this->hidden->buffer, aa_image(context), local_this->hidden->w, aa_imgwidth (context), local_this->hidden->h, aa_imgheight (context));
	aa_renderpalette(context, local_this->hidden->palette, local_this->hidden->rparams, 0, 0, aa_scrwidth(context), aa_scrheight(context));
	aa_flush(context);
}

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

/* We need to wait for vertical retrace on page flipped displays */
static int AA_LockHWSurface(_THIS, SDL_Surface *surface)
{
	/* TODO ? */
	return(0);
}
static void AA_UnlockHWSurface(_THIS, SDL_Surface *surface)
{
	return;
}

/* FIXME: How is this done with AAlib? */
static int AA_FlipHWSurface(_THIS, SDL_Surface *surface)
{
	SDL_mutexP(AA_mutex);
	aa_flush(AA_context);
	SDL_mutexV(AA_mutex);
	return(0);
}

static void AA_DirectUpdate(_THIS, int numrects, SDL_Rect *rects)
{
	int i;
	SDL_Rect *rect;

	fastscale (AA_buffer, aa_image(AA_context), AA_w, aa_imgwidth (AA_context), AA_h, aa_imgheight (AA_context));
#if 1
	aa_renderpalette(AA_context, AA_palette, AA_rparams, 0, 0, aa_scrwidth(AA_context), aa_scrheight(AA_context));
#else
	/* Render only the rectangles in the list */
	printf("Update rects : ");
	for ( i=0; i < numrects; ++i ) {
		rect = &rects[i];
		printf("(%d,%d-%d,%d)", rect->x, rect->y, rect->w, rect->h);
		aa_renderpalette(AA_context, AA_palette, AA_rparams, rect->x * AA_x_ratio, rect->y * AA_y_ratio, rect->w * AA_x_ratio, rect->h * AA_y_ratio);
	}
	printf("\n");
#endif
	SDL_mutexP(AA_mutex);
	aa_flush(AA_context);
	SDL_mutexV(AA_mutex);
	return;
}

int AA_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors)
{
	int i;

	for ( i=0; i < ncolors; i++ ) {
	        aa_setpalette(AA_palette, firstcolor + i,
			      colors[i].r>>2,
			      colors[i].g>>2,
			      colors[i].b>>2);
	}
	return(1);
}

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

	aa_uninitkbd(AA_context);
	aa_uninitmouse(AA_context);

	/* Free video mode lists */
	for ( i=0; i<SDL_NUMMODES; ++i ) {
		if ( SDL_modelist[i] != NULL ) {
			SDL_free(SDL_modelist[i]);
			SDL_modelist[i] = NULL;
		}
	}
	
	aa_close(AA_context);

	SDL_DestroyMutex(AA_mutex);

	this->screen->pixels = NULL;	
}