view test/loopwave.c @ 1555:780fd5b61df1

Fixed bug #89 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 12:05:16 +0000
parents 0394f8ebc42d
children 14717b52abc0
line wrap: on
line source


/* Program to load a wave file and loop playing it using SDL sound */

/* loopwaves.c is much more robust in handling WAVE files -- 
	This is only for simple WAVEs
*/
#include "SDL_config.h"

#include <stdio.h>
#include <stdlib.h>

#if HAVE_SIGNAL_H
#include <signal.h>
#endif

#include "SDL.h"
#include "SDL_audio.h"

struct {
	SDL_AudioSpec spec;
	Uint8   *sound;			/* Pointer to wave data */
	Uint32   soundlen;		/* Length of wave data */
	int      soundpos;		/* Current play position */
} wave;


/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void quit(int rc)
{
	SDL_Quit();
	exit(rc);
}


void fillerup(void *unused, Uint8 *stream, int len)
{
	Uint8 *waveptr;
	int    waveleft;

	/* Set up the pointers */
	waveptr = wave.sound + wave.soundpos;
	waveleft = wave.soundlen - wave.soundpos;

	/* Go! */
	while ( waveleft <= len ) {
		SDL_MixAudio(stream, waveptr, waveleft, SDL_MIX_MAXVOLUME);
		stream += waveleft;
		len -= waveleft;
		waveptr = wave.sound;
		waveleft = wave.soundlen;
		wave.soundpos = 0;
	}
	SDL_MixAudio(stream, waveptr, len, SDL_MIX_MAXVOLUME);
	wave.soundpos += len;
}

static int done = 0;
void poked(int sig)
{
	done = 1;
}

int main(int argc, char *argv[])
{
	char name[32];

	/* Load the SDL library */
	if ( SDL_Init(SDL_INIT_AUDIO) < 0 ) {
		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
		return(1);
	}
	if ( argv[1] == NULL ) {
		argv[1] = "sample.wav";
	}
	/* Load the wave file into memory */
	if ( SDL_LoadWAV(argv[1],
			&wave.spec, &wave.sound, &wave.soundlen) == NULL ) {
		fprintf(stderr, "Couldn't load %s: %s\n",
						argv[1], SDL_GetError());
		quit(1);
	}

	wave.spec.callback = fillerup;
#if HAVE_SIGNAL_H
	/* Set the signals */
#ifdef SIGHUP
	signal(SIGHUP, poked);
#endif
	signal(SIGINT, poked);
#ifdef SIGQUIT
	signal(SIGQUIT, poked);
#endif
	signal(SIGTERM, poked);
#endif /* HAVE_SIGNAL_H */

	/* Initialize fillerup() variables */
	if ( SDL_OpenAudio(&wave.spec, NULL) < 0 ) {
		fprintf(stderr, "Couldn't open audio: %s\n", SDL_GetError());
		SDL_FreeWAV(wave.sound);
		quit(2);
	}
	SDL_PauseAudio(0);

	/* Let the audio run */
	printf("Using audio driver: %s\n", SDL_AudioDriverName(name, 32));
	while ( ! done && (SDL_GetAudioStatus() == SDL_AUDIO_PLAYING) )
		SDL_Delay(1000);

	/* Clean up on signal */
	SDL_CloseAudio();
	SDL_FreeWAV(wave.sound);
	SDL_Quit();
	return(0);
}