OAL stream: actually use buffer samples instead of buffer size

This was the idea from the beginning. Also reduce the buffer length to about
half a second.

* cosmetic changes

opl/opl_sdl.c

@@ -147,15 +147,13 @@ static void FillBuffer(uint8_t *buffer, unsigned int nsamples)
 
 // Callback function to fill a new sound buffer:
 
-static int OPL_Callback(byte *stream, int len)
+static uint32_t OPL_Callback(byte *buffer, uint32_t buffer_samples)
 {
-    unsigned int filled, buffer_samples;
+    unsigned int filled;
-    uint8_t *buffer = stream;
 
     // Repeatedly call the OPL emulator update function until the buffer is
     // full.
     filled = 0;
-    buffer_samples = len / 4;
 
     while (filled < buffer_samples)
     {
@@ -196,7 +194,8 @@ static int OPL_Callback(byte *stream, int len)
 
         AdvanceTime(nsamples);
     }
-    return len;
+
+    return buffer_samples;
 }
 
 static void OPL_SDL_Shutdown(void)

src/i_flmusic.c

@@ -52,18 +52,18 @@ static fluid_player_t *player = NULL;
 static char **soundfonts;
 static int soundfonts_num;
 
-static int FL_Callback(byte *stream, int len)
+static uint32_t FL_Callback(byte *buffer, uint32_t buffer_samples)
 {
     int result;
 
-    result = fluid_synth_write_s16(synth, len / 4, stream, 0, 2, stream, 1, 2);
+    result = fluid_synth_write_s16(synth, buffer_samples, buffer, 0, 2, buffer, 1, 2);
 
     if (result != FLUID_OK)
     {
-        fprintf(stderr, "Error generating FluidSynth audio\n");
+        fprintf(stderr, "FL_Callback: Error generating FluidSynth audio\n");
     }
 
-    return len;
+    return buffer_samples;
 }
 
 // Load SNDFONT lump

src/i_oalmusic.c

@@ -28,10 +28,10 @@
 #include "i_sound.h"
 
 // Define the number of buffers and buffer size (in milliseconds) to use. 4
-// buffers with 8192 samples each gives a nice per-chunk size, and lets the
+// buffers with 4096 samples each gives a nice per-chunk size, and lets the
-// queue last for almost one second at 44.1khz.
+// queue last for about half second at 44.1khz.
 #define NUM_BUFFERS 4
-#define BUFFER_SAMPLES 8192
+#define BUFFER_SAMPLES 4096
 
 typedef struct
 {
@@ -44,6 +44,7 @@ typedef struct
     // The format of the output stream
     ALenum format;
     ALsizei freq;
+    ALsizei frame_size;
 } stream_player_t;
 
 static stream_player_t player;
@@ -69,6 +70,7 @@ static boolean UpdatePlayer(void)
     // Unqueue and handle each processed buffer
     while (processed > 0)
     {
+        uint32_t frames;
         ALuint bufid;
         ALsizei size;
 
@@ -79,14 +81,16 @@ static boolean UpdatePlayer(void)
         // the source.
         if (callback)
         {
-            size = callback(player.data, BUFFER_SAMPLES);
+            frames = callback(player.data, BUFFER_SAMPLES);
         }
         else
         {
-            size = I_SND_FillStream(player.data, BUFFER_SAMPLES);
+            frames = I_SND_FillStream(player.data, BUFFER_SAMPLES);
         }
-        if (size > 0)
+
+        if (frames > 0)
         {
+            size = frames * player.frame_size;
             alBufferData(bufid, player.format, player.data, size, player.freq);
             alSourceQueueBuffers(player.source, 1, &bufid);
         }
@@ -124,7 +128,7 @@ static boolean StartPlayer(void)
 {
     int i;
 
-    player.data = malloc(BUFFER_SAMPLES);
+    player.data = malloc(BUFFER_SAMPLES * player.frame_size);
 
     // Rewind the source position and clear the buffer queue.
     alSourceRewind(player.source);
@@ -133,23 +137,26 @@ static boolean StartPlayer(void)
     // Fill the buffer queue
     for (i = 0; i < NUM_BUFFERS; i++)
     {
+        uint32_t frames;
         ALsizei size;
 
         // Get some data to give it to the buffer
         if (callback)
         {
-            size = callback(player.data, BUFFER_SAMPLES);
+            frames = callback(player.data, BUFFER_SAMPLES);
         }
         else
         {
-            size = I_SND_FillStream(player.data, BUFFER_SAMPLES);
+            frames = I_SND_FillStream(player.data, BUFFER_SAMPLES);
         }
 
-        if (size < 1)
+        if (frames < 1)
             break;
 
-        alBufferData(player.buffers[i], player.format, player.data,
+        size = frames * player.frame_size;
-                     size, player.freq);
+
+        alBufferData(player.buffers[i], player.format, player.data, size,
+                    player.freq);
     }
     if (alGetError() != AL_NO_ERROR)
     {
@@ -267,7 +274,11 @@ static void I_OAL_ShutdownMusic(void)
 
 static void *I_OAL_RegisterSong(void *data, int len)
 {
-    if (I_SND_OpenStream(data, len, &player.format, &player.freq) == false)
+    boolean result;
+
+    result = I_SND_OpenStream(data, len, &player.format, &player.freq,
+                              &player.frame_size);
+    if (!result)
         return NULL;
 
     StartPlayer();
@@ -294,6 +305,7 @@ void I_OAL_HookMusic(callback_func_t callback_func)
 
         player.format = AL_FORMAT_STEREO16;
         player.freq = SND_SAMPLERATE;
+        player.frame_size = 2 * sizeof(short);
 
         I_OAL_SetGain(1.0f);
         StartPlayer();

src/i_oalmusic.h

@@ -19,7 +19,7 @@
 
 #include "doomtype.h"
 
-typedef int (*callback_func_t)(byte *data, int size);
+typedef uint32_t (*callback_func_t)(byte *buffer, uint32_t buffer_samples);
 
 void I_OAL_HookMusic(callback_func_t callback_func);
 void I_OAL_SetGain(float gain);

src/i_sndfile.c

@@ -198,7 +198,7 @@ typedef struct
 
     sample_format_t sample_format;
     ALenum format;
-    ALint byteblockalign;
+    ALint frame_size;
 } sndfile_t;
 
 static void CloseFile(sndfile_t *file)
@@ -214,7 +214,7 @@ static boolean OpenFile(sndfile_t *file, void *data, sf_count_t size)
 {
     sample_format_t sample_format;
     ALenum format;
-    ALint byteblockalign;
+    ALint frame_size;
 
     file->sfdata.data = data;
     file->sfdata.length = size;
@@ -262,15 +262,15 @@ static boolean OpenFile(sndfile_t *file, void *data, sf_count_t size)
             break;
     }
 
-    byteblockalign = 1;
+    frame_size = 1;
 
     if (sample_format == Int16)
     {
-        byteblockalign = file->sfinfo.channels * 2;
+        frame_size = file->sfinfo.channels * 2;
     }
     else if (sample_format == Float)
     {
-        byteblockalign = file->sfinfo.channels * 4;
+        frame_size = file->sfinfo.channels * 4;
     }
 
     // Figure out the OpenAL format from the file and desired sample type.
@@ -301,7 +301,7 @@ static boolean OpenFile(sndfile_t *file, void *data, sf_count_t size)
 
     file->sample_format = sample_format;
     file->format = format;
-    file->byteblockalign = byteblockalign;
+    file->frame_size = frame_size;
 
     return true;
 }
@@ -318,7 +318,7 @@ boolean I_SND_LoadFile(void *data, ALenum *format, byte **wavdata,
         return false;
     }
 
-    local_wavdata = malloc(file.sfinfo.frames * file.byteblockalign / file.sfinfo.channels);
+    local_wavdata = malloc(file.sfinfo.frames * file.frame_size / file.sfinfo.channels);
 
     if (file.sample_format == Int16)
     {
@@ -341,7 +341,7 @@ boolean I_SND_LoadFile(void *data, ALenum *format, byte **wavdata,
 
     *wavdata = local_wavdata;
     *format = file.format;
-    *size = num_frames * file.byteblockalign / file.sfinfo.channels;
+    *size = num_frames * file.frame_size / file.sfinfo.channels;
     *freq = file.sfinfo.samplerate;
 
     CloseFile(&file);
@@ -352,7 +352,8 @@ boolean I_SND_LoadFile(void *data, ALenum *format, byte **wavdata,
 static sndfile_t stream;
 static boolean looping;
 
-boolean I_SND_OpenStream(void *data, ALsizei size, ALenum *format, ALsizei *freq)
+boolean I_SND_OpenStream(void *data, ALsizei size, ALenum *format,
+                         ALsizei *freq, ALsizei *frame_size)
 {
     if (OpenFile(&stream, data, size) == false)
     {
@@ -361,6 +362,7 @@ boolean I_SND_OpenStream(void *data, ALsizei size, ALenum *format, ALsizei *freq
 
     *format = stream.format;
     *freq = stream.sfinfo.samplerate;
+    *frame_size = stream.frame_size;
 
     return true;
 }
@@ -370,10 +372,9 @@ void I_SND_SetLooping(boolean on)
     looping = on;
 }
 
-int I_SND_FillStream(byte *data, ALsizei size)
+uint32_t I_SND_FillStream(byte *data, uint32_t frames)
 {
     sf_count_t num_frames = 0;
-    sf_count_t frames = size / stream.byteblockalign;
 
     if (stream.sample_format == Int16)
     {
@@ -389,7 +390,7 @@ int I_SND_FillStream(byte *data, ALsizei size)
         sf_seek(stream.sndfile, 0, SEEK_SET);
     }
 
-    return (num_frames * stream.byteblockalign);
+    return num_frames;
 }
 
 void I_SND_CloseStream(void)

src/i_sndfile.h

@@ -25,9 +25,10 @@
 boolean I_SND_LoadFile(void *data, ALenum *format, byte **wavdata,
                        ALsizei *size, ALsizei *freq);
 
-boolean I_SND_OpenStream(void *data, ALsizei size, ALenum *format, ALsizei *freq);
+boolean I_SND_OpenStream(void *data, ALsizei size, ALenum *format,
+                         ALsizei *freq, ALsizei *frame_size);
 void I_SND_SetLooping(boolean on);
-int I_SND_FillStream(byte *data, ALsizei size);
+uint32_t I_SND_FillStream(byte *data, uint32_t frames);
 void I_SND_CloseStream(void);
 
 #endif