medfall

commit f3f4af7dfc5051e894a96326a639491dea64a6e3
parent 56db176eadfa05b60f3eaaaa9cac38ac226498f2
Author: Michael Savage <mikejsavage@gmail.com>
Date:   Mon Oct 24 20:34:09 +0300

Mixer cleanup

Diffstat:
mixer.cc
 | 
38
++++++++++++++++----------------------
1 file changed, 16 insertions(+), 22 deletions(-)
diff --git a/mixer.cc b/mixer.cc
@@ -1,11 +1,12 @@
 #include "intrinsics.h"
+#include "int_conversions.h"
 #include "mixer.h"
 #include "platform_audio_output.h"
 #include "nonblocking_fixed_spsc_queue.h"
 
 struct PlayingSound {
 	SoundData data;
-	s32 num_played_samples; // TODO: ssize_t?
+	s32 num_played_samples;
 	float volume;
 	u16 next_free;
 	// TODO: next_playing? allows us to make playing implicit
@@ -42,7 +43,7 @@ static Thread mixer_thread;
 static PlayingSoundID sound_counter;
 
 static bool mixer_sound_id_to_slot( PlayingSoundID sound_id, size_t * slot ) {
-	for( size_t i = 0; i < array_count( playing_sounds ); i++ ) {
+	for( size_t i = 0; i < ARRAY_COUNT( playing_sounds ); i++ ) {
 		if( ids[ i ] == sound_id ) {
 			*slot = i;
 			return true;
@@ -73,7 +74,7 @@ static bool mixer_find_free_slot( size_t * free_slot ) {
 
 static void mixer_stop_all_impl() {
 	first_free_sound = 0;
-	for( size_t i = 0; i < array_count( playing_sounds ); i++ ) {
+	for( size_t i = 0; i < ARRAY_COUNT( playing_sounds ); i++ ) {
 		playing_sounds[ i ].playing = false;
 		playing_sounds[ i ].next_free = i + 1;
 		ids[ i ] = INVALID_SOUND_ID;
@@ -121,24 +122,21 @@ static void mixer_process_command( MixerCommand cmd ) {
 static void mixer_mix_sound( PlayingSound * ps, float * samples, size_t num_samples ) {
 	// TODO: simd
 
-	// TODO: there is some funny casting in here
-	s32 samples_to_write = num_samples;
+	s32 samples_to_write = checked_cast< s32 >( num_samples );
 	if( !ps->loop ) {
-		samples_to_write = min( samples_to_write, ( s32 ) ps->data.num_samples - ps->num_played_samples );
+		samples_to_write = min( samples_to_write, checked_cast< s32 >( ps->data.num_samples ) - ps->num_played_samples );
 	}
 
-	float scale = 1.0f / float( S16_MAX );
-	for( size_t i = 0; i < samples_to_write; i++ ) {
-		// TODO: this is not quite right
-		size_t j = ( ps->num_played_samples + i ) % ps->data.num_samples;
-		samples[ i ] += float( ps->data.samples[ j ] ) * scale * ps->volume;
+	for( s32 i = 0; i < samples_to_write; i++ ) {
+		s32 j = ( ps->num_played_samples + i ) % ps->data.num_samples;
+		samples[ i ] += dequantize11s( ps->data.samples[ j ], 16 ) * ps->volume;
 	}
 
 	ps->num_played_samples += samples_to_write;
 	if( ps->loop ) {
 		ps->num_played_samples %= ps->data.num_samples;
 	}
-	else if( ps->num_played_samples == ps->data.num_samples ) {
+	else if( ps->num_played_samples == checked_cast< s32 >( ps->data.num_samples ) ) {
 		ps->playing = false;
 	}
 }
@@ -147,8 +145,6 @@ static THREAD( mixer_thread_proc ) {
 	AudioOutputDevice * output_device = ( AudioOutputDevice * ) data;
 
 	for( ;; ) {
-		// TODO: limit how many commands we process at once so people
-		// can't jam the queue and make us skip
 		for( size_t i = 0; i < COMMAND_QUEUE_SIZE; i++ ) {
 			MixerCommand cmd;
 			if( !command_queue.dequeue( &cmd ) ) break;
@@ -157,24 +153,23 @@ static THREAD( mixer_thread_proc ) {
 
 		// TODO: channels
 		float samples[ 2048 ];
-		for( size_t i = 0; i < array_count( samples ); i++ ) {
+		for( size_t i = 0; i < ARRAY_COUNT( samples ); i++ ) {
 			samples[ i ] = 0.0f;
 		}
 
-		for( size_t i = 0; i < array_count( playing_sounds ); i++ ) {
+		for( size_t i = 0; i < ARRAY_COUNT( playing_sounds ); i++ ) {
 			PlayingSound & ps = playing_sounds[ i ];
 			if( ps.playing ) {
-				mixer_mix_sound( &ps, samples, array_count( samples ) );
+				mixer_mix_sound( &ps, samples, ARRAY_COUNT( samples ) );
 			}
 		}
 
 		s16 finalised_samples[ 2048 ];
-		for( size_t i = 0; i < array_count( samples ); i++ ) {
-			// TODO: this float -> s16 is not quite right
-			finalised_samples[ i ] = clamp11( samples[ i ] ) * S16_MAX;
+		for( size_t i = 0; i < ARRAY_COUNT( samples ); i++ ) {
+			finalised_samples[ i ] = quantize11s( clamp11( samples[ i ] ), 16 );
 		}
 
-		audio_output_write( output_device, finalised_samples, array_count( finalised_samples ) );
+		audio_output_write( output_device, finalised_samples, ARRAY_COUNT( finalised_samples ) );
 	}
 
 	THREAD_END;
@@ -193,7 +188,6 @@ void mixer_term() {
 }
 
 PlayingSoundID mixer_play( SoundData sound, MixerLoopBool loop, s32 start_pos ) {
-	// TODO: check start_pos fits in PlayingSound.num_played_samples
 	MixerCommand cmd;
 	cmd.type = MIXER_PLAY;
 	cmd.sound_to_play = sound;