sfx: add volume control to sfx_play()

Preparatory commit for experimenting with varying volumes based
on distance.  Impetus is an interest in making the TV clips
always play when the TV appears, but vary the volume with
distance.

3 files changed, 24 insertions, 17 deletions

diff --git a/src/game.c b/src/game.c
index 65b8d62..2b46001 100644
--- a/src/game.c
+++ b/src/game.c
@@ -422,7 +422,7 @@ static void infect_entity(game_t *game, entity_t *entity, const char *name)
 {
 	/* convert entity into inanimate virus (off the viruses array) */
 	(void) virus_node_new(&(stage_conf_t){ .stage = entity->any.node, .replace = 1, .name = name, .active = 1, .alpha = 1.f }, &game->sars->projection_x, &entity->any.model_x);
-	sfx_play(&sfx.baby_infected);
+	sfx_play(&sfx.baby_infected, 1.f);
 	entity->any.type = ENTITY_TYPE_VIRUS;
 	entity->virus.corpse = 1;
 
@@ -435,7 +435,7 @@ static void infect_entity(game_t *game, entity_t *entity, const char *name)
 static void hat_baby(game_t *game, baby_t *baby, mask_t *mask)
 {
 	(void) baby_hatted_node_new(&(stage_conf_t){ .stage = baby->entity.node, .replace = 1, .name = "baby-hatted", .active = 1, .alpha = 1.f }, &game->sars->projection_x, &baby->entity.model_x);
-	sfx_play(&sfx.baby_hatted);
+	sfx_play(&sfx.baby_hatted, 1.f);
 
 	stage_set_active(mask->entity.node, 0);
 }
@@ -454,7 +454,7 @@ static void maga_adult(game_t *game, adult_t *adult, maga_t *maga)
 	 * memory ensured maga was always off initially.
 	 */
 	game->is_maga = 1;
-	sfx_play(&sfx.adult_maga);
+	sfx_play(&sfx.adult_maga, 1.f);
 	stage_set_active(maga->entity.node, 0);
 }
 
@@ -464,13 +464,13 @@ static void mask_adult(game_t *game, adult_t *adult, mask_t *mask)
 	if (game->is_maga) { /* MAGA discards masks */
 		stage_set_active(mask->entity.node, 0);
 
-		return sfx_play(&sfx.adult_maga);
+		return sfx_play(&sfx.adult_maga, 1.f);
 	}
 
 	(void) adult_masked_node_new(&(stage_conf_t){ .stage = adult->entity.node, .replace = 1, .name = "adult-masked", .active = 1, .alpha = 1.f }, &game->sars->projection_x, &adult->entity.model_x);
 
 	adult->masked += GAME_MASK_PROTECTION;
-	sfx_play(&sfx.adult_mine);
+	sfx_play(&sfx.adult_mine, 1.f);
 	stage_set_active(mask->entity.node, 0);
 }
 
@@ -481,9 +481,9 @@ static int expose_adult(game_t *game, adult_t *adult, virus_t *virus)
 	if (adult->masked) {
 		if (!--adult->masked) {
 			(void) adult_node_new(&(stage_conf_t){ .stage = adult->entity.node, .replace = 1, .name = "adult-unmasked", .active = 1, .alpha = 1.f }, &game->sars->projection_x, &adult->entity.model_x);
-			sfx_play(&sfx.adult_unmasked);
+			sfx_play(&sfx.adult_unmasked, 1.f);
 		} else
-			sfx_play(&sfx.adult_maskhit);
+			sfx_play(&sfx.adult_maskhit, 1.f);
 		(void) flash_entity(game, &adult->entity, 4);
 		reset_virus(virus);
 
@@ -492,11 +492,11 @@ static int expose_adult(game_t *game, adult_t *adult, virus_t *virus)
 
 	/* convert adult into inanimate virus (off the viruses array) */
 	(void) virus_node_new(&(stage_conf_t){ .stage = adult->entity.node, .replace = 1, .name = "adult-virus", .active = 1, .alpha = 1.f }, &game->sars->projection_x, &adult->entity.model_x);
-	sfx_play(&sfx.adult_infected);
+	sfx_play(&sfx.adult_infected, 1.f);
 
 	if (adult->holding) {
 		(void) virus_node_new(&(stage_conf_t){ .stage = adult->holding->entity.node, .replace = 1, .name = "baby-virus", .active = 1, .alpha = 1.f }, &game->sars->projection_x, &adult->holding->entity.model_x);
-		sfx_play(&sfx.baby_infected);
+		sfx_play(&sfx.baby_infected, 1.f);
 	}
 
 	game->state = GAME_STATE_OVER;
@@ -510,7 +510,7 @@ static void pickup_baby(game_t *game, adult_t *adult, baby_t *baby)
 	if (adult->holding)
 		return;
 
-	sfx_play(&sfx.baby_held);
+	sfx_play(&sfx.baby_held, 1.f);
 	adult->holding = baby;
 	adult->holding->entity.position = adult->entity.position;
 	entity_update_x(game, &adult->holding->entity);
@@ -523,7 +523,7 @@ static void more_teepee(game_t *game, teepee_t *teepee)
 	if (game->adult->holding) {
 		/* disallow picking up teepee if holding something, flash what's held and the teepee we missed */
 		if (flash_entity(game, &teepee->entity, 5))
-			sfx_play(&sfx.adult_armsfull);
+			sfx_play(&sfx.adult_armsfull, 1.f);
 		(void) flash_entity(game, &game->adult->holding->entity, 5);
 
 		return;
@@ -558,7 +558,7 @@ static void more_teepee(game_t *game, teepee_t *teepee)
 	}
 	(*teepee->bonus_release) = BONUS_NODE_RELEASE_MS;
 	(*teepee->bonus_release_position) = teepee->entity.position;
-	sfx_play(&sfx.adult_mine);
+	sfx_play(&sfx.adult_mine, 1.f);
 	stage_set_active(teepee->entity.node, 0);
 }
 
@@ -990,12 +990,12 @@ static ix2_search_status_t adult_search(void *cb_context, ix2_object_t *ix2_obje
 
 	case ENTITY_TYPE_TV:
 		game->adult->captivated = 1;
-		sfx_play(&sfx.adult_captivated);
+		sfx_play(&sfx.adult_captivated, 1.f);
 		/* shifted because rand() tends to have more activity in the upper bits,
 		 * but this could be more careful about avoiding repetition by randomizing
 		 * a 0-9 list every time it stepped through said list. TODO
 		 */
-		sfx_play(&sfx.tv_talk[(rand() >> 8) % NELEMS(sfx.tv_talk)]);
+		sfx_play(&sfx.tv_talk[(rand() >> 8) % NELEMS(sfx.tv_talk)], 1.f);
 
 		return IX2_SEARCH_STOP_HIT;
 
@@ -1057,7 +1057,7 @@ static void game_move_adult(game_t *game, v2f_t *dir)
 		    game->adult->entity.position.y < -1.05f) {
 
 			/* rescued baby */
-			sfx_play(&sfx.baby_rescued);
+			sfx_play(&sfx.baby_rescued, 1.f);
 
 			/* make the rescued baby available for respawn reuse */
 			game->adult->holding->entity.flashes_remaining = 0;
diff --git a/src/sfx.c b/src/sfx.c
index 04b0fbc..334833a 100644
--- a/src/sfx.c
+++ b/src/sfx.c
@@ -63,10 +63,16 @@ void sfx_init(void)
 }
 
 
-void sfx_play(sfx_sound_t *sound)
+/* play sfx, volume 0-1 */
+void sfx_play(sfx_sound_t *sound, float volume)
 {
 	assert(sound);
 
+	if (volume > 1.f)
+		volume = 1.f;
+	else if (volume < 0.f)
+		volume = 0.f;
+
 	if (sound->chunk) {
 		int	channel;
 
@@ -74,6 +80,7 @@ void sfx_play(sfx_sound_t *sound)
 		if (channel < 0)
 			channel = Mix_GroupOldest(sound->voice);
 
+		Mix_Volume(channel, MIX_MAX_VOLUME * volume);
 		Mix_PlayChannel(channel, sound->chunk, 0);
 	}
 }
diff --git a/src/sfx.h b/src/sfx.h
index a37b22c..48d797b 100644
--- a/src/sfx.h
+++ b/src/sfx.h
@@ -48,6 +48,6 @@ typedef struct sfx_t {
 extern sfx_t	sfx;
 
 void sfx_init(void);
-void sfx_play(sfx_sound_t *sound);
+void sfx_play(sfx_sound_t *sound, float volume);
 
 #endif