Command-line option for audio debugging

Make clipping sound a little less horrendous (still pretty bad)
Count number of clipped samples


git-svn-id: svn://cook.msm.cam.ac.uk:745/thrust3d/thrust3d@114 84d2e878-0bd5-11dd-ad15-13eda11d74c5

5 files changed, 24 insertions, 9 deletions

diff --git a/src/audio.c b/src/audio.c
index 8e84c5e..6735665 100644
--- a/src/audio.c
+++ b/src/audio.c
@@ -21,7 +21,7 @@
 static void audio_mix(void *data, Uint8 *stream8, int len) {
 
 	AudioContext *a = data;
-	int i, j;
+	int i, j, clip_count;
 	Sint16 *stream = (Sint16 *)stream8;
 	
 	len /= 2;	/* Samples */
@@ -32,6 +32,7 @@ static void audio_mix(void *data, Uint8 *stream8, int len) {
 	}
 	
 	/* For each currently playing sound... */
+	clip_count = 0;
 	for ( i=0; i<AUDIO_MAX_SOUNDS; i++ ) {
 		
 		/* Playing? */
@@ -40,9 +41,18 @@ static void audio_mix(void *data, Uint8 *stream8, int len) {
 		for ( j=0; j<len; j++ ) {
 		
 			Sint16 samp;
+			Sint32 test;
 			
 			samp = a->sounds[i].data[a->sounds[i].dpos++];
-			stream[j] += samp * a->sounds[i].volume;
+			test = stream[j] + samp*a->sounds[i].volume;
+			if ( test > 32767 ) {
+				if ( stream[j] != 32767 ) {
+					clip_count++;
+				}
+				stream[j] = 32767;
+			} else {
+				stream[j] += samp * a->sounds[i].volume;
+			}
 			
 			if ( a->sounds[i].dpos == a->sounds[i].dlen ) {
 				if ( a->sounds[i].repeat ) {
@@ -60,6 +70,8 @@ static void audio_mix(void *data, Uint8 *stream8, int len) {
 		
 	}
 	
+	if ( a->debug && (clip_count > 0) ) printf("AU: Clipped %i samples.\n", clip_count);
+	
 }
 
 void audio_play(AudioContext *a, char *file, float volume, int repeat) {
@@ -108,7 +120,7 @@ void audio_play(AudioContext *a, char *file, float volume, int repeat) {
 }
 
 /* SDL audio initial setup */
-AudioContext *audio_setup() {
+AudioContext *audio_setup(int debug) {
 	
 	AudioContext *a;
 	SDL_AudioSpec fmt;
@@ -119,7 +131,7 @@ AudioContext *audio_setup() {
 	if ( a == NULL ) return NULL;
 	
 	/* Initialise audio context */
-	a->debug = 0;
+	a->debug = debug;
 	for ( i=0; i<AUDIO_MAX_SOUNDS; i++ ) {
 		a->sounds[i].inuse = 0;
 	}
diff --git a/src/audio.h b/src/audio.h
index 703f6c0..769b398 100644
--- a/src/audio.h
+++ b/src/audio.h
@@ -18,7 +18,7 @@
 
 #include "types.h"
 
-extern AudioContext *audio_setup(void);
+extern AudioContext *audio_setup(int debug);
 extern void audio_shutdown(AudioContext *ctx);
 extern void audio_play(AudioContext *a, char *file, float volume, int repeat);
 
diff --git a/src/game.c b/src/game.c
index a68144e..233acc9 100644
--- a/src/game.c
+++ b/src/game.c
@@ -224,7 +224,7 @@ static void game_load_all_connected(Game *game) {
 }
 
 /* Create a new "game" structure */
-Game *game_new(int width, int height, int disable_vbos, int disable_fbos, int disable_shaders) {
+Game *game_new(int width, int height, int disable_vbos, int disable_fbos, int disable_shaders, int audio_debug) {
 
 	Game *g;
 	
@@ -261,7 +261,7 @@ Game *game_new(int width, int height, int disable_vbos, int disable_fbos, int di
 	/* Note: render_setup() initialises GLEW, which must be done before loading models. */
 	
 	/* Audio setup */
-	g->audio = audio_setup();
+	g->audio = audio_setup(audio_debug);
 	if ( g->audio == NULL ) {
 		fprintf(stderr, "Couldn't initialise audio\n");
 		free(g);
diff --git a/src/game.h b/src/game.h
index 5cb27b9..011f64f 100644
--- a/src/game.h
+++ b/src/game.h
@@ -21,7 +21,7 @@
 #include "types.h"
 
 extern void game_check_handoff(Game *game);
-extern Game *game_new(int width, int height, int disable_vbos, int disable_fbos, int disable_shaders);
+extern Game *game_new(int width, int height, int disable_vbos, int disable_fbos, int disable_shaders, int audio_debug);
 extern void game_shutdown(Game *game);
 extern Room *game_find_room(Game *game, int rx, int ry, int rz);
 extern void game_pause(Game *game);
diff --git a/src/main.c b/src/main.c
index c17a42e..71f6928 100644
--- a/src/main.c
+++ b/src/main.c
@@ -55,6 +55,7 @@ int main(int argc, char *argv[]) {
 	int disable_vbos = 0;
 	int disable_fbos = 0;
 	int disable_shaders = 0;
+	int audio_debug = 0;
 	const struct option longopts[] = {	{"fullscreen", 0, NULL, 'f'},
 						{"resolution", 1, NULL, 'r'},
 						{"help", 0, NULL, 'h'},
@@ -62,6 +63,7 @@ int main(int argc, char *argv[]) {
 						{"disable-vbos", 0, &disable_vbos, 1},
 						{"disable-fbos", 0, &disable_fbos, 1},
 						{"disable-shaders", 0, &disable_shaders, 1},
+						{"audio-debug", 0, &audio_debug, 1},
 						{0, 0, NULL, 0}				};
 
 	
@@ -107,6 +109,7 @@ int main(int argc, char *argv[]) {
 				printf("       --disable-vbos       Disable the use of vertex buffer objects (advanced).\n");
 				printf("       --disable-fbos       Disable the use of framebuffer objects (advanced).\n");
 				printf("       --disable-shaders    Disable the use of shaders (advanced).\n");
+				printf("       --audio-debug        Print audio debugging messages to stdout (advanced).\n");
 				printf("  -f,  --fullscreen         Use the full screen.\n\n");
 				printf("Allowable values for <res> are as follows:\n\n");
 				printf("<res>    Width   Height\n");
@@ -164,7 +167,7 @@ int main(int argc, char *argv[]) {
 	
 	/* World setup */
 	Game *game;
-	game = game_new(width, height, disable_vbos, disable_fbos, disable_shaders);
+	game = game_new(width, height, disable_vbos, disable_fbos, disable_shaders, audio_debug);
 	
 	/* Main loop */
 	finished = 0;