PC audio now supports volume and stereo channels.

joeylib/src/jSDL2.c

@@ -32,7 +32,7 @@
 #include "jPixBuf.h"
 
 
-#define AUDIO_FORMAT     AUDIO_F32
+#define AUDIO_FORMAT     AUDIO_F32  // PocketMod returns floats.
 #define AUDIO_FREQUENCY  44100
 #define AUDIO_CHANNELS   2
 
@@ -73,6 +73,7 @@ static SDL_AudioSpec        _jlAudioFormat;
 static SDL_AudioDeviceID    _jlAudioDevice;
 static jbool                _jlModPlaying        = jfalse;
 static jlPlatformModT      *_jlModCurrent        = NULL;
+static jbyte                _jlModVolume         = 255;
 static jlSoundPlayingT     *_jlSoundList         = NULL;
 
 
@@ -80,6 +81,9 @@ static Uint32 _jlUtilTimer(Uint32 interval, void *param);
 static void   _jlAudioCallback(void *userdata, Uint8 *buffer, int bytes);
 
 
+extern jbool _jlSwapChannels;
+
+
 /*
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Wcast-align"
@@ -154,11 +158,21 @@ void _jlPutPixel(SDL_Surface *surface, int x, int y, Uint32 pixel) {
 
 
 static void _jlAudioCallback(void *userdata, Uint8 *buffer, int bytes) {
-	int              i     = 0;
+	int              i                = 0;
-	jlSoundPlayingT *sound = NULL;
+	jlSoundPlayingT *sound            = NULL;
-	jlSoundPlayingT *prev  = NULL;
+	jlSoundPlayingT *prev             = NULL;
-	jlSoundPlayingT *temp  = NULL;
+	jlSoundPlayingT *temp             = NULL;
-	uint32_t         length;
+	uint32_t         length           = 0;
+	float           *data             = NULL;
+	float           *out              = NULL;
+	float            adjust           = 1;
+	double           work             = 0;
+	uint8_t         *mix              = NULL;
+	jbool            isRight          = jfalse;
+	static uint8_t  *samples          = NULL;
+	static uint32_t  sampleBufferSize = 0;
+
+	(void)userdata;
 
 	// Silence buffer.
 	memset(buffer, 0, bytes);
@@ -166,8 +180,25 @@ static void _jlAudioCallback(void *userdata, Uint8 *buffer, int bytes) {
 	// Load in music.
 	if (_jlModPlaying) {
 		while (i < bytes) {
-			//***TODO*** No MOD volume control.
+			i += pocketmod_render(&_jlModContext, buffer + i, bytes - i);
-			i += pocketmod_render(userdata, buffer + i, bytes - i);
+		}
+		// Adjust volume.
+		adjust = ((100.0 / 255.0) * (float)_jlModVolume) * 0.01;
+		data   = (float *)buffer;
+		for (i=0; i<(int)(bytes / sizeof(float)); i+=2) {
+			data[i]     *= adjust;
+			data[i + 1] *= adjust;
+		}
+	}
+
+	// Create a sample buffer for manipulating sound effects.
+	if (sampleBufferSize < (uint32_t)bytes) {
+		if (samples) jlFree(samples);
+		samples = jlMalloc(bytes);
+		if (samples) {
+			sampleBufferSize = bytes;
+		} else {
+			sampleBufferSize = 0;
 		}
 	}
 
@@ -175,8 +206,32 @@ static void _jlAudioCallback(void *userdata, Uint8 *buffer, int bytes) {
 	if (_jlSoundList) {
 		sound = _jlSoundList;
 		while (sound) {
-			length = ((uint32_t)bytes > sound->len) ? sound->len : bytes;
+			length = ((uint32_t)bytes > sound->len) ? sound->len : (uint32_t)bytes;
-			SDL_MixAudioFormat(buffer, sound->buffer, AUDIO_FORMAT, length, sound->volume * 0.5);
+			// If we have a sample buffer, move sound to desired channel.
+			if (samples) {
+				mix  = samples;
+				out  = (float *)samples;
+				data = (float *)sound->buffer;
+				for (i=0; i<(int)(length / sizeof(float)); i+=2) {
+					// Combine channels into a mono sample.
+					work = (data[i] + data[i + 1]) * 0.5;
+					// Determine channel.
+					isRight = (sound->channel & 0x01);
+					if (_jlSwapChannels) isRight = !isRight;
+					if (isRight) {
+						// Move sound into right channel.
+						out[i]     = 0;
+						out[i + 1] = work;
+					} else {
+						// Move sound into left channel.
+						out[i]     = work;
+						out[i + 1] = 0;
+					}
+				}
+			} else {
+				mix = sound->buffer;
+			}
+			SDL_MixAudioFormat(buffer, mix, AUDIO_FORMAT, length, sound->volume * 0.5);
 			sound->buffer += length;
 			sound->len    -= length;
 			// Are we done with this sound?
@@ -391,6 +446,11 @@ void jlModStop(void) {
 }
 
 
+void jlModVolume(jbyte volume) {
+	_jlModVolume = volume;
+}
+
+
 void jlSoundFree(jlSoundT *sound) {
 	jlPlatformSoundT *s    = (jlPlatformSoundT *)sound;
 
@@ -662,7 +722,7 @@ int main(int argc, char *argv[]) {
 	_jlAudioFormat.channels = 2;
 	_jlAudioFormat.samples  = AUDIO_CHANNELS;
 	_jlAudioFormat.callback = _jlAudioCallback;
-	_jlAudioFormat.userdata = &_jlModContext;
+	_jlAudioFormat.userdata = NULL;
 	_jlAudioDevice = SDL_OpenAudioDevice(NULL, 0, &_jlAudioFormat, &_jlAudioFormat, SDL_AUDIO_ALLOW_FREQUENCY_CHANGE);
 	if (!_jlAudioDevice) jlUtilDie(SDL_GetError());
 	SDL_PauseAudioDevice(_jlAudioDevice, 0);

joeylib/src/joey.c

@@ -74,6 +74,10 @@ jmp_buf    _jlJumpBuffer;
 jbool      _jlIsRunning        = jtrue;
 #endif
 
+#ifndef JL_HAS_SOUNDSWAPCHANNELS
+jbool      _jlSwapChannels     = jfalse;
+#endif
+
 
 static jlColorT       _jlDefaultPalette[16];
 static jlStackT      *_jlFillStackTop       = NULL;
@@ -797,6 +801,13 @@ void jlModStop(void) {
 #endif
 
 
+#ifndef JL_HAS_MODVOLUME
+void jlModVolume(jbyte volume) {
+	(void)volume;
+}
+#endif
+
+
 #ifndef JL_HAS_PALETTEDEFAULT
 void jlPaletteDefault(void) {
 	jbyte i;
@@ -882,6 +893,13 @@ void jlSoundStop(jlSoundT *sound) {
 #endif
 
 
+#ifndef JL_HAS_SOUNDSWAPCHANNELS
+void jlSoundSwapChannels(jbool swap) {
+	_jlSwapChannels = swap;
+}
+#endif
+
+
 #ifndef JL_HAS_STNFREE
 void jlStnFree(jlStnT *stn) {
 	if (stn != NULL) {

joeylib/src/joey.h

@@ -98,6 +98,7 @@ typedef unsigned int   juint32;
 #define JL_HAS_MODPAUSE
 #define JL_HAS_MODPLAY
 #define JL_HAS_MODSTOP
+#define JL_HAS_MODVOLUME
 #define JL_HAS_PALETTESET
 #define JL_HAS_PALETTESETFROMIMG
 #define JL_HAS_SOUNDFREE
@@ -142,6 +143,7 @@ typedef unsigned int   juint32;
 #define JL_HAS_MODPAUSE
 #define JL_HAS_MODPLAY
 #define JL_HAS_MODSTOP
+#define JL_HAS_MODVOLUME
 #define JL_HAS_PALETTESET
 #define JL_HAS_PALETTESETFROMIMG
 #define JL_HAS_SOUNDFREE
@@ -186,6 +188,7 @@ typedef unsigned int   juint32;
 #define JL_HAS_MODPAUSE
 #define JL_HAS_MODPLAY
 #define JL_HAS_MODSTOP
+#define JL_HAS_MODVOLUME
 #define JL_HAS_PALETTESET
 #define JL_HAS_PALETTESETFROMIMG
 #define JL_HAS_SOUNDFREE
@@ -440,6 +443,7 @@ jbool        _jlModLoad(jlModT **mod, char *filename);
 void          jlModPause(void);
 void          jlModPlay(jlModT *mod);
 void          jlModStop(void);
+void          jlModVolume(jbyte volume);
 
 void          jlPaletteDefault(void);  //***TODO*** Treat palettes like we do "surfaces" - allow changing STAs or display
 void          jlPaletteSet(jbyte index, jbyte r, jbyte g, jbyte b);  //***TODO*** Really need a matching "get"
@@ -451,6 +455,7 @@ jbool         jlSoundIsPlaying(jlSoundT *sound);
 jbool        _jlSoundLoad(jlSoundT **sound, char *filename);
 void          jlSoundPlay(jlSoundT *sound, jlSoundChannelE channel, jbyte volume);
 void          jlSoundStop(jlSoundT *sound);
+void          jlSoundSwapChannels(jbool swap);
 
 void          jlStnFree(jlStnT *stn);
 #define       jlStnLoad(stn, filename) _jlStnLoad((jlStnT **)&(stn), filename, __LINE__, (char *)__FILE__)  // Syntatic Sugar

joeylib/src/test.c

@@ -290,6 +290,7 @@ void musicTest(void) {
 	jlModT   *music  = NULL;
 	jlSoundT *sound1 = NULL;
 	jlSoundT *sound2 = NULL;
+	jbyte     volume = 0;
 
 	if (!jlImgLoad(kanga, "kanga")) jlUtilDie("Unable to load kanga.img!");
 	if (!jlImgLoad(font, "font")) jlUtilDie("Unable to load font.img!");
@@ -302,12 +303,17 @@ void musicTest(void) {
 
 	jlModPlay(music);
 
-	jlSoundPlay(sound2, CHANNEL_FRONT_RIGHT, 255);
+	//jlSoundSwapChannels(jtrue);
 	jlSoundPlay(sound1, CHANNEL_FRONT_LEFT, 255);
+	jlSoundPlay(sound2, CHANNEL_FRONT_RIGHT, 255);
 
 	while (!jlKeyPressed()) {
 		fontPrint(font, NULL, 1, 1, "%dx%d %d %d     ", jlGameGetAxis(0), jlGameGetAxis(1), jlGameGetButton(0), jlGameGetButton(1));
 		jlDisplayPresent();
+		if (volume < 255) {
+			volume++;
+			jlModVolume(volume);
+		}
 	}
 	jlKeyRead();