From e464f244207191ef512cde95c8fbaa69652d983e Mon Sep 17 00:00:00 2001
From: cosmonaut <evan@moonside.games>
Date: Wed, 27 Oct 2021 22:07:19 -0700
Subject: [PATCH] fix various AddBuffer problems

---
 src/FAudioGMS.c | 44 +++++++++++++++++++++++++-------------------
 1 file changed, 25 insertions(+), 19 deletions(-)

diff --git a/src/FAudioGMS.c b/src/FAudioGMS.c
index f4c4efc..78377c4 100644
--- a/src/FAudioGMS.c
+++ b/src/FAudioGMS.c
@@ -164,6 +164,8 @@ typedef struct FAudioGMS_StreamingSound
 {
     stb_vorbis* fileHandle;
     stb_vorbis_info info;
+    float* streamBuffer;
+    uint32_t streamBufferSize;
 } FAudioGMS_StreamingSound;
 
 typedef struct FAudioGMS_SoundInstance
@@ -226,8 +228,6 @@ typedef struct FAudioGMS_EffectChain
 static const float SPEED_OF_SOUND = 343.5f;
 static const float DOPPLER_SCALE = 1.0f;
 
-#define STREAMING_BUFFER_SIZE 1024 * 16 * sizeof(float) /* FIXME: what should this value be? */
-
 typedef struct FAudioGMS_Device
 {
     FAudio* handle;
@@ -253,7 +253,6 @@ typedef struct FAudioGMS_Device
     uint32_t effectChainCount;
     IdStack effectChainIndexStack;
 
-    float streamStagingBuffer[STREAMING_BUFFER_SIZE];
     double timestep;
 } FAudioGMS_Device;
 
@@ -788,30 +787,33 @@ static FAudioGMS_SoundInstance* FAudioGMS_INTERNAL_SoundInstance_CreateFromStati
 
 static void FAudioGMS_INTERNAL_SoundInstance_AddBuffer(FAudioGMS_SoundInstance* instance)
 {
+    uint32_t requestedSampleCount = instance->format.nSamplesPerSec / 4;
+
+    uint32_t requiredStagingBufferSize = requestedSampleCount * instance->format.nChannels * sizeof(float);
+    if (instance->soundData.streamingSound.streamBufferSize < requiredStagingBufferSize)
+    {
+        instance->soundData.streamingSound.streamBuffer = SDL_realloc(instance->soundData.streamingSound.streamBuffer, requiredStagingBufferSize);
+    }
+
     /* NOTE: this function returns samples per channel, not total samples */
-    uint32_t samples = stb_vorbis_get_samples_float_interleaved(
+    uint32_t sampleCount = stb_vorbis_get_samples_float_interleaved(
         instance->soundData.streamingSound.fileHandle,
         instance->format.nChannels,
-        device->streamStagingBuffer,
-        STREAMING_BUFFER_SIZE
+        instance->soundData.streamingSound.streamBuffer,
+        requestedSampleCount * instance->format.nChannels
     );
 
-    uint32_t sampleCount = samples * instance->format.nChannels;
-    uint32_t bufferLength = sampleCount * sizeof(float);
-
-    uint8_t* nextBuffer = SDL_malloc(bufferLength);
-    SDL_memcpy(nextBuffer, device->streamStagingBuffer, bufferLength);
-
     FAudioBuffer buffer;
-    buffer.AudioBytes = bufferLength;
-    buffer.pAudioData = nextBuffer;
-    buffer.PlayLength =
-        bufferLength /
-        instance->format.nChannels /
-        (instance->format.wBitsPerSample / 8);
+    buffer.AudioBytes = sampleCount * instance->format.nChannels * sizeof(float);
+    buffer.pAudioData = (uint8_t*) instance->soundData.streamingSound.streamBuffer;
     buffer.PlayBegin = 0;
+    buffer.PlayLength = sampleCount;
 
     buffer.Flags = 0;
+    /*(sampleCount < instance->soundData.streamingSound.info.sample_rate) ?
+        FAUDIO_END_OF_STREAM :
+        0;
+        */
     buffer.LoopBegin = 0;
     buffer.LoopCount = 0;
     buffer.LoopLength = 0;
@@ -820,7 +822,8 @@ static void FAudioGMS_INTERNAL_SoundInstance_AddBuffer(FAudioGMS_SoundInstance*
     FAudioSourceVoice_SubmitSourceBuffer(instance->handle, &buffer, NULL);
 
     /* We have reached the end of the file! */
-    if (sampleCount < STREAMING_BUFFER_SIZE)
+    /* FIXME: maybe move this to a OnStreamEnd callback? */
+    if (sampleCount < requestedSampleCount)
     {
         if (instance->loop)
         {
@@ -856,6 +859,8 @@ double FAudioGMS_StreamingSound_LoadOGG(char* filePath)
 
     instance->soundData.streamingSound.fileHandle = fileHandle;
     instance->soundData.streamingSound.info = info;
+    instance->soundData.streamingSound.streamBuffer = NULL;
+    instance->soundData.streamingSound.streamBufferSize = 0;
 
     FAudioGMS_INTERNAL_SoundInstance_AddBuffer(instance);
 
@@ -1247,6 +1252,7 @@ static void FAudioGMS_INTERNAL_SoundInstance_Destroy(FAudioGMS_SoundInstance* in
         FAudioVoice_DestroyVoice(instance->handle);
         if (!instance->isStatic)
         {
+            SDL_free(instance->soundData.streamingSound.streamBuffer);
             stb_vorbis_close(instance->soundData.streamingSound.fileHandle);
         }
         if (instance->is3D)