view test/loopwave.c @ 3877:81f66f258d77 SDL-1.2

Fixed bug #281 ------- Comment #2 From Christian Walther 2006-07-23 07:37 [reply] ------- Wow, that was an interesting bug to chase. It was a timing issue: it seems that for some reason, a certain time must pass between ShowMenuBar() being called in QZ_UnsetVideoMode() and the application quitting. Before rev. 1885, this delay was provided by the slow hand-coded fade. With the asynchronous Core Graphics fading introduced in rev. 1885, that delay was no longer present (most of the time) and the bug became apparent. Adding an SDL_Delay(100) somewhere between ShowMenuBar() and the end of QZ_VideoQuit() lowered the frequency of the bug appearing from "almost every time" to "very rarely" here. However, there is another solution: doing the ShowMenuBar() before releasing the captured display instead of afterwards. Apparently, no delay is necessary in that case, and it looks nicer to me anyway because it is the reverse order of the way things are set up in the beginning: capture display - set video mode - hide menu bar - ... - show menu bar - reset video mode - release captured display. So, this is what the attached patch does. In addition, I've taken the liberty of - removing some unused code that I forgot to remove in rev. 1885, - fixing two warnings about undeclared functions in SDL_QuartzVideo.m by including OpenGL.h (whose name is a bit misleading - it only declares CGL stuff, so there's no interference with SDL_opengl.h).
author Sam Lantinga <slouken@libsdl.org>
date Sun, 24 Sep 2006 01:27:40 +0000
parents 290b5baf2fca
children 8b9d79e7eacf c121d94672cb e905bb5d9bc3
line wrap: on
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/* 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 SDLCALL 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);
}