From fe8a6e86127eab6ac284b921ccdf550e5ee99ba9 Mon Sep 17 00:00:00 2001
From: Nevyn Bengtsson <nevyn@alloverse.com>
Date: Wed, 25 Nov 2020 21:14:24 +0100
Subject: [PATCH] expose Source:{get|set}Spatial

---
 src/api/l_audio_source.c  | 15 +++++++++++++++
 src/modules/audio/audio.c | 26 +++++++++++++++++++++-----
 src/modules/audio/audio.h |  2 ++
 3 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/src/api/l_audio_source.c b/src/api/l_audio_source.c
index 65f72715..7824637a 100644
--- a/src/api/l_audio_source.c
+++ b/src/api/l_audio_source.c
@@ -51,6 +51,19 @@ static int l_lovrSourceSetVolume(lua_State* L) {
   return 0;
 }
 
+static int l_lovrSourceGetSpatial(lua_State* L) {
+  Source* source = luax_checktype(L, 1, Source);
+  lua_pushboolean(L, lovrSourceGetSpatial(source));
+  return 1;
+}
+
+static int l_lovrSourceSetSpatial(lua_State* L) {
+  Source* source = luax_checktype(L, 1, Source);
+  bool spatial = lua_toboolean(L, 2);
+  lovrSourceSetSpatial(source, spatial);
+  return 0;
+}
+
 static int l_lovrSourceGetDuration(lua_State* L) {
   Source* source = luax_checktype(L, 1, Source);
   TimeUnit units = luax_checkenum(L, 2, TimeUnit, "seconds");
@@ -104,6 +117,8 @@ const luaL_Reg lovrSource[] = {
   { "setLooping", l_lovrSourceSetLooping },
   { "getVolume", l_lovrSourceGetVolume },
   { "setVolume", l_lovrSourceSetVolume },
+  { "getSpatial", l_lovrSourceGetSpatial },
+  { "setSpatial", l_lovrSourceSetSpatial },
   { "getDuration", l_lovrSourceGetDuration },
   { "getTime", l_lovrSourceGetTime },
   { "setTime", l_lovrSourceSetTime },
diff --git a/src/modules/audio/audio.c b/src/modules/audio/audio.c
index 7362a633..ca89d43c 100644
--- a/src/modules/audio/audio.c
+++ b/src/modules/audio/audio.c
@@ -30,6 +30,7 @@ struct Source {
   bool playing;
   bool looping;
   bool spatial;
+  int output_channel_count;
 };
 
 typedef struct {
@@ -67,7 +68,7 @@ static bool mix(Source* source, float* output, uint32_t count) {
         // could skip min-ing with one of the buffers if you can guarantee that one is bigger/equal to the other (you can because their formats are known)
 
     uint64_t framesIn = source->sound->read(source->sound, source->offset, chunk, raw);
-    uint64_t framesOut = sizeof(aux) / (sizeof(float) * (2 >> source->spatial));
+    uint64_t framesOut = sizeof(aux) / (sizeof(float) * source->output_channel_count);
 
     ma_data_converter_process_pcm_frames(source->converter, raw, &framesIn, aux, &framesOut);
 
@@ -237,13 +238,19 @@ Source* lovrSourceCreate(SoundData* sound) {
   source->sound = sound;
   lovrRetain(source->sound);
   source->volume = 1.f;
+  lovrSourceSetSpatial(source, false);
 
+  return source;
+}
+
+void _lovrSourceAssignConverter(Source *source) {
+  source->converter = NULL;
   for (size_t i = 0; i < state.converters.length; i++) {
     ma_data_converter* converter = &state.converters.data[i];
     if (converter->config.formatIn != formats[source->sound->format]) continue;
     if (converter->config.sampleRateIn != source->sound->sampleRate) continue;
     if (converter->config.channelsIn != source->sound->channels) continue;
-    if (converter->config.channelsOut != (2 >> source->spatial)) continue;
+    if (converter->config.channelsOut != source->output_channel_count) continue;
     source->converter = converter;
     break;
   }
@@ -253,7 +260,7 @@ Source* lovrSourceCreate(SoundData* sound) {
     config.formatIn = formats[source->sound->format];
     config.formatOut = ma_format_f32;
     config.channelsIn = source->sound->channels;
-    config.channelsOut = 2 >> source->spatial;
+    config.channelsOut = source->output_channel_count;
     config.sampleRateIn = source->sound->sampleRate;
     config.sampleRateOut = SAMPLE_RATE;
     arr_expand(&state.converters, 1);
@@ -261,8 +268,6 @@ Source* lovrSourceCreate(SoundData* sound) {
     lovrAssert(!ma_data_converter_init(&config, converter), "Problem creating Source data converter");
     source->converter = converter;
   }
-
-  return source;
 }
 
 void lovrSourceDestroy(void* ref) {
@@ -316,6 +321,17 @@ void lovrSourceSetVolume(Source* source, float volume) {
   ma_mutex_unlock(&state.locks[AUDIO_PLAYBACK]);
 }
 
+bool lovrSourceGetSpatial(Source *source)
+{
+  return source->spatial;
+}
+void lovrSourceSetSpatial(Source *source, bool spatial)
+{
+  source->spatial = spatial;
+  source->output_channel_count = source->spatial ? 1 : 2;
+  _lovrSourceAssignConverter(source);
+}
+
 uint32_t lovrSourceGetTime(Source* source) {
   return source->offset;
 }
diff --git a/src/modules/audio/audio.h b/src/modules/audio/audio.h
index 5908d90a..a44bd6a3 100644
--- a/src/modules/audio/audio.h
+++ b/src/modules/audio/audio.h
@@ -45,6 +45,8 @@ bool lovrSourceIsLooping(Source* source);
 void lovrSourceSetLooping(Source* source, bool isLooping);
 float lovrSourceGetVolume(Source* source);
 void lovrSourceSetVolume(Source* source, float volume);
+bool lovrSourceGetSpatial(Source *source);
+void lovrSourceSetSpatial(Source *source, bool spatial);
 uint32_t lovrSourceGetTime(Source* source);
 void lovrSourceSetTime(Source* source, uint32_t sample);
 struct SoundData* lovrSourceGetSoundData(Source* source);